Natural Radioactivity

**References**

[1] Dolchinkov N. Analysis and

net/publication/313109065

Report NRA. Sofia; 2015

[4] Communication from the Commission to the Council and the European Parliament. Communication on Nuclear non-Proliferation. Brussels;

054 28.02.2005. p. 1

publication/321905753

[5] Commission Regulation (Euratom) No 302/2005 of 8 February 2005 on the application of Euratom safeguards— Council/Commission statement, OJ L

[6] Dolchinkov N. Modernization of monitoring and public notification systems in case of radioactive pollution of the environment in Bulgaria. Scientific and Practical Journal "Global Nuclear Safety". 2017;**3**(24):7-18. Available from: https://www.researchgate.net/

[7] Dolchinkov N. Investigation of the state of the radiation control systems and the actions of the competent authorities and the population in the event of a change in the radiation background in Bulgaria. In: International Conference Knowledge-Based Organization Subuy,

2009

**38**

optimization of the national automated system for continuous control of the radiation gamma background. In: Third National Congress of Physical Sciences; Sofia; 2016. ISBN: 978-954-580-364-2. Available from: https://www.researchgate.

*Recent Techniques and Applications in Ionizing Radiation Research*

Romania. Vol. 24, Issue 3. 2018.

[8] Dolchinkov N, Nichev N. Structure and management of the national automated system for permanent control of the radiation gamma background in Bulgaria. Land Forces Academy Review. Sibiu, Romania: De Gruyter Open. Vol. XXII, No 2(86);

[9] Dolchinkov N. Optimization of the systems for monitoring and public disclosure of radioactive contamination of the environment. International Journal Knowledge, Skopie. 2015;**15**(1): 423-431. ISSN 1857-92. Available from:

https://www.researchgate.net/

[10] Dolchinkov N. State of the population disclosure systems in the changing radiation situation in Bulgaria. In: 12th International Scientific and Practical Conference on Environment, Technology, and Resources, Vol. 1. Rēzekne, Latvia; 20–22 June, 2019.

pp. 54-58. ISBN: 1691-5402

of the environment in Bulgaria [Dissertation for acquisition of NSA Doctor]. Veliko Tarnovo: NMU; 2017. Available from: http://nvu.bg/node/

1895

7166-38-0

[11] Dolchinkov N. Optimization of the systems for monitoring and public disclosure of radioactive contamination

[12] Dolchinkov N. Historical overview and analysis of national automated system for continuous monitoring of gamma radiation. In: VIII Scientific and Practical Seminar with International Participation "Economic Security of the State and Scientific and Technological Aspects of its Provision", Kyiv; October 21–22, 2016. рp. 220-228. ISBN: 978-966-

publication/320378173

рp. 38-44

2017. pp. 115-121

[2] The Council of Ministers, Annual

[3] Commission Regulation (EC) No 1609/2000 of 24 July 2000 establishing a list of products excluded from the application of Council Regulation (EEC) No 737/90 on the conditions governing imports of agricultural products originating in third countries following the accident at the Chernobyl nuclear power station, OJ L 185 25.07.2000. p. 27

**Chapter 4**

**Abstract**

*Entesar H. Elaraby*

application to measure these concentrations.

**1. The source of natural radioactive**

and the effect of the magnetic field in it [1].

**1.2 Internal or ground radiation**

**1.1 Cosmic radiation**

**41**

**Keywords:** alpha particle, radon, HPGD, SSNTD, NAA, TPT

to three main types: cosmic radiation, internal or ground radiation.

Natural Radioactive Decay

This chapter is primarily concerned with natural radioactive decay. Generally speaking, there are two types of natural radioactive decays: alpha decays "which contain two neutrons and two protons" emitted from radon gas; additionally, nuclear decay by emission of photons (γ-decay). This chapter aims to describe γ and alpha loss of nuclei and demonstrates how to measure the radioactive material naturally using solid-state nuclear track detector (SSNTD) and high purity Germanium detector (HPGD). Also, methods of measuring the different characteristics of the alpha particle using the track profile technique (TPT) will be presented. Finally, results will be presented in the alpha and radon measurements. The concentration of aerosols has attracted much attention by many researchers in the past decade. Research has shown that aerosols are responsible for harmful chemical reactions that lead to the physical degradation of the stratospheric ozone layer. Moreover, aerosols increase the risk of developing cancer in humans when inhaled in large proportions. Therefore, neutron activation analysis (NAA) is a very important

There are multiple sources that cause natural radiation. These sources are limited

The Earth is constantly bombarded by cosmic rays that affect all living things. The charged particles in the radiation interact with the Earth's magnetic field and result in an overflow of radiation from beta and gamma, the intensity of which and the value of the radiation dose differ according to the different nature of the place

Ground or internal radiation is present in everything that surrounds us, such as water, air and vegetation. Different levels of radioactive material from uranium, its daughters, thorium and its daughters, have been found in various places on Earth. The radiation levels vary depending on where they are measured and depend on the amount of uranium and thorium atoms present in the soil. Exposure to radiation occurs by inhaling radon gas, one of the sons of uranium and thorium, or ingesting radioactive atoms in food and water, where there are proportions of them that vary

#### **Chapter 4**

## Natural Radioactive Decay

*Entesar H. Elaraby*

### **Abstract**

This chapter is primarily concerned with natural radioactive decay. Generally speaking, there are two types of natural radioactive decays: alpha decays "which contain two neutrons and two protons" emitted from radon gas; additionally, nuclear decay by emission of photons (γ-decay). This chapter aims to describe γ and alpha loss of nuclei and demonstrates how to measure the radioactive material naturally using solid-state nuclear track detector (SSNTD) and high purity Germanium detector (HPGD). Also, methods of measuring the different characteristics of the alpha particle using the track profile technique (TPT) will be presented. Finally, results will be presented in the alpha and radon measurements. The concentration of aerosols has attracted much attention by many researchers in the past decade. Research has shown that aerosols are responsible for harmful chemical reactions that lead to the physical degradation of the stratospheric ozone layer. Moreover, aerosols increase the risk of developing cancer in humans when inhaled in large proportions. Therefore, neutron activation analysis (NAA) is a very important application to measure these concentrations.

**Keywords:** alpha particle, radon, HPGD, SSNTD, NAA, TPT

#### **1. The source of natural radioactive**

There are multiple sources that cause natural radiation. These sources are limited to three main types: cosmic radiation, internal or ground radiation.

#### **1.1 Cosmic radiation**

The Earth is constantly bombarded by cosmic rays that affect all living things. The charged particles in the radiation interact with the Earth's magnetic field and result in an overflow of radiation from beta and gamma, the intensity of which and the value of the radiation dose differ according to the different nature of the place and the effect of the magnetic field in it [1].

#### **1.2 Internal or ground radiation**

Ground or internal radiation is present in everything that surrounds us, such as water, air and vegetation. Different levels of radioactive material from uranium, its daughters, thorium and its daughters, have been found in various places on Earth. The radiation levels vary depending on where they are measured and depend on the amount of uranium and thorium atoms present in the soil. Exposure to radiation occurs by inhaling radon gas, one of the sons of uranium and thorium, or ingesting radioactive atoms in food and water, where there are proportions of them that vary according to the location. Sites with high levels of radiation have higher dose levels [2]. High doses cause lung cancer and pose a major threat to human health [3]. Therefore it is important to measure the ground radiation from uranium and uranium decay, such as thorium, radium, and radon.

#### **2. Radioactive decay**

#### **2.1 Alpha decay**

The process of unstable (or radioactive) atoms becomes stable by emitting radiation. This event over time is called radioactive decay.

Alpha decay results in the loss of two protons and two neutrons from the nucleus.

$$\mathbf{^A Z} \rightarrow \mathbf{^{A-4} Z} \\ \mathbf{^\cdot Y} + \mathbf{^{4} a} + \mathbf{energy} \text{ (Q)} \tag{1}$$

**2.2 Gamma decay**

*Natural Radioactive Decay*

*DOI: http://dx.doi.org/10.5772/intechopen.91899*

from the nucleus.

**Figure 2.**

**43**

*Gamma ray emitting from transitions in the decay of 12B.*

**3. Measurement of radioactive**

**3.1 Measurement of alpha particle and radon**

tor such as: inorganic crystals, glasses and plastics.

A gamma ray *γ* has very high electromagnetic radiation carrying energy away

When a nucleus disintegrates by emitting an α-particle or a β-particle, the daughter nucleus may be left in an excited state, if the excited nucleus does not break apart or emit another particle, it can de-excite to the ground state by emitting

<sup>6</sup> <sup>C</sup><sup>∗</sup> <sup>þ</sup> *<sup>e</sup>*

The Solid State Nuclear Track Detector SSNTDs is a polymer used for detecting energetic charged particles such as protons and alpha–particles. SSNTDs an insulating solid naturally and manmade occurring and there are many types of this detec-

The CR-39 Solid State Nuclear Track Detector is known to be widely used for radon gas measurement. CR39 is sensitive also to detect proton and neutron dosimeter and cosmic ray investigations. The ability of CR-39 to record the location of a radiation source, even at extremely low concentrations is exploited in autoradiography studies with alpha particles, and for detection of alpha emitters. The interaction of the energetic particles with the polymer results in the formation of latent tracks. These latent tracks can be made by chemical etching of the polymer.

*<sup>Z</sup>*X þ *γ* (4)

� þ *ν* (5)

<sup>6</sup> C þ *γ* (6)

*A* ∗ *<sup>Z</sup>* <sup>X</sup> ! *<sup>A</sup>*

a high energy photon or gamma (*γ*) ray. As we see in **Figure 2**.

12 <sup>5</sup> <sup>B</sup> ! <sup>12</sup>

> 12 <sup>6</sup> <sup>C</sup><sup>∗</sup> ! <sup>12</sup>

$$^{226}\_{88}\text{Ra} \rightarrow ^{222}\_{86}\text{Rn} + ^{4}\_{2}\alpha + \text{energy} \;(Q) \tag{2}$$

X is parent atom and Y is daughter atom, and *Q* the energy is carried away primarily by the kinetic energy of the alpha particle.

Alpha particles are often observed to be produced on their own energy, meaning that the parent nucleus is converted to the basic state of the daughter's nucleus by emitting a particle with energy that corresponds to the value of the entire *Q*. But the degradation processes of the alpha particles may be associated with the emission of photons. As shown in **Figure 1**. This indicates the presence of energy levels and the underlying quantum structure of separate states in the nuclei as in atomic transformations. The nucleus decomposes into the excited state of the daughter's nucleus, in which case the lowest effective *Q*<sup>⋱</sup> *<sup>α</sup>* value. The daughter nucleus can later decay to ground state by releasing a photon. Hence a series of decay occurs

$$\mathbf{^A\_Z X \to \mathbf{^{A-4}\_Z \ast} Y + \mathbf{^4\_2} a + \text{energy } \left( \mathbf{Q\_a^{\cdot \cdot}} \right)}\tag{3}$$

**Figure 1.** *Alpha particle transitions in the decay of 228Th. Source: Das and Ferbel.*

#### **2.2 Gamma decay**

according to the location. Sites with high levels of radiation have higher dose levels [2]. High doses cause lung cancer and pose a major threat to human health [3]. Therefore it is important to measure the ground radiation from uranium and ura-

The process of unstable (or radioactive) atoms becomes stable by emitting

Alpha decay results in the loss of two protons and two neutrons from the

<sup>2</sup>*α* þ energy ð Þ *Q* (1)

<sup>2</sup>*α* þ energy ð Þ *Q* (2)

*<sup>α</sup>* value. The daughter nucleus can

(3)

*<sup>Z</sup>*�<sup>2</sup> <sup>Y</sup> <sup>þ</sup> <sup>4</sup>

<sup>86</sup> Rn <sup>þ</sup> <sup>4</sup>

X is parent atom and Y is daughter atom, and *Q* the energy is carried away

later decay to ground state by releasing a photon. Hence a series of decay occurs

<sup>2</sup>*<sup>α</sup>* <sup>þ</sup> energy *<sup>Q</sup>*<sup>⋱</sup>

*α*

Alpha particles are often observed to be produced on their own energy, meaning that the parent nucleus is converted to the basic state of the daughter's nucleus by emitting a particle with energy that corresponds to the value of the entire *Q*. But the degradation processes of the alpha particles may be associated with the emission of photons. As shown in **Figure 1**. This indicates the presence of energy levels and the underlying quantum structure of separate states in the nuclei as in atomic transformations. The nucleus decomposes into the excited state of the daughter's

nium decay, such as thorium, radium, and radon.

*Recent Techniques and Applications in Ionizing Radiation Research*

radiation. This event over time is called radioactive decay.

*A <sup>Z</sup>*<sup>X</sup> ! *<sup>A</sup>*�<sup>4</sup>

226 <sup>88</sup> Ra ! <sup>222</sup>

primarily by the kinetic energy of the alpha particle.

nucleus, in which case the lowest effective *Q*<sup>⋱</sup>

*A*

*Alpha particle transitions in the decay of 228Th. Source: Das and Ferbel.*

*<sup>Z</sup>*<sup>X</sup> ! *<sup>A</sup>*�<sup>4</sup> <sup>∗</sup> *<sup>Z</sup>*�<sup>2</sup> <sup>Y</sup> <sup>þ</sup> <sup>4</sup>

**2. Radioactive decay**

**2.1 Alpha decay**

nucleus.

**Figure 1.**

**42**

A gamma ray *γ* has very high electromagnetic radiation carrying energy away from the nucleus.

$$\mathbf{x}\_Z^{A\*}\mathbf{X} \to \mathbf{x}\_Z^{A}\mathbf{X} + \mathbf{y} \tag{4}$$

When a nucleus disintegrates by emitting an α-particle or a β-particle, the daughter nucleus may be left in an excited state, if the excited nucleus does not break apart or emit another particle, it can de-excite to the ground state by emitting a high energy photon or gamma (*γ*) ray. As we see in **Figure 2**.

$$\mathbf{c}\_{\mathfrak{F}}^{12}\mathbf{B} \to \,^{12}\_{6}\mathbf{C}^\* + \mathbf{e}^- + \overline{\nu} \tag{5}$$

$$\rm \, ^{12}\_{6}\rm \rm C\*} \rightarrow \, ^{12}\_{6}\rm \rm C+} \tag{6}$$

#### **3. Measurement of radioactive**

#### **3.1 Measurement of alpha particle and radon**

The Solid State Nuclear Track Detector SSNTDs is a polymer used for detecting energetic charged particles such as protons and alpha–particles. SSNTDs an insulating solid naturally and manmade occurring and there are many types of this detector such as: inorganic crystals, glasses and plastics.

The CR-39 Solid State Nuclear Track Detector is known to be widely used for radon gas measurement. CR39 is sensitive also to detect proton and neutron dosimeter and cosmic ray investigations. The ability of CR-39 to record the location of a radiation source, even at extremely low concentrations is exploited in autoradiography studies with alpha particles, and for detection of alpha emitters. The interaction of the energetic particles with the polymer results in the formation of latent tracks. These latent tracks can be made by chemical etching of the polymer.

**Figure 2.** *Gamma ray emitting from transitions in the decay of 12B.*

CR-39 sheets is cut into small detectors of area 1.2 cm 1.5 cm each. The exposure time for sample is 30 days (to reach secular equilibrium) for 222Rn determination see **Figure 3**.

After exposure the CR-39 detectors were etched in 6.25 normal NaOH at 70°C for 6 h. The different parameter of track such as the track density ρ, track diameter D and track length *L* are measured by using optical microscope. **Figure 4** shows that the track of particle which incidence on the surface of detector [4, 5].

To measure the Track Profile Technique (TPT) of alpha particle as **Figure 5** you must irradiate the sides (the edges) of the detector by 241Am source of alpha particle with energy of five under normal incidence.

**Figure 3.** *The chamber used to measure the radon and alpha in soil.*

**3.2 Determination of the bulk etching rate** *V***<sup>B</sup> and range of alpha particle**

*The track profile of deferent energy of alpha particle at deferent bulk etch rate.*

relation [6].

**Figure 5.**

*Natural Radioactive Decay*

*DOI: http://dx.doi.org/10.5772/intechopen.91899*

tor material.

**45**

The method involves a direct measurement of the track lengths in both phases of evolution; the acute-conical and the over etched phases. Accordingly, the maximum value of the track length (*L*max) at the saturation point and also the corresponding saturation time (*t*sat), which is the time required for track length to reach the maximum and constant value, to be determined in accordance with the energy of the alpha particle which in turn can be used to calculate *V*<sup>B</sup> according to the

> *<sup>V</sup>*<sup>B</sup> <sup>¼</sup> *<sup>R</sup>*th � *<sup>L</sup>*max *t*est

where *R*th is the theoretical range of alpha particle energy incident on the detec-

Track profile was obtained as mentioned before and the range of certain particle

where *L*eR is the track length just very close to the end of track *L*eR = *V*T*t*R, *V*<sup>T</sup> is the track etch rate and *h* is the removal thickness layer (*h* = *V*B*t*R), *t*<sup>R</sup> is the time

*R* ¼ *L*eR þ *h*<sup>R</sup> (8)

track energy in the detector was measured using the relation

needed to reach to the end of track.

(7)

**Figure 4.** *The reading under the microscope.*

CR-39 sheets is cut into small detectors of area 1.2 cm 1.5 cm each. The exposure time for sample is 30 days (to reach secular equilibrium) for 222Rn

the track of particle which incidence on the surface of detector [4, 5].

*Recent Techniques and Applications in Ionizing Radiation Research*

After exposure the CR-39 detectors were etched in 6.25 normal NaOH at 70°C for 6 h. The different parameter of track such as the track density ρ, track diameter D and track length *L* are measured by using optical microscope. **Figure 4** shows that

To measure the Track Profile Technique (TPT) of alpha particle as **Figure 5** you must irradiate the sides (the edges) of the detector by 241Am source of alpha particle

determination see **Figure 3**.

**Figure 3.**

**Figure 4.**

**44**

*The reading under the microscope.*

with energy of five under normal incidence.

*The chamber used to measure the radon and alpha in soil.*


**Figure 5.** *The track profile of deferent energy of alpha particle at deferent bulk etch rate.*

#### **3.2 Determination of the bulk etching rate** *V***<sup>B</sup> and range of alpha particle**

The method involves a direct measurement of the track lengths in both phases of evolution; the acute-conical and the over etched phases. Accordingly, the maximum value of the track length (*L*max) at the saturation point and also the corresponding saturation time (*t*sat), which is the time required for track length to reach the maximum and constant value, to be determined in accordance with the energy of the alpha particle which in turn can be used to calculate *V*<sup>B</sup> according to the relation [6].

$$V\_{\rm B} = \frac{R\_{\rm th} - L\_{\rm max}}{t\_{\rm est}} \tag{7}$$

where *R*th is the theoretical range of alpha particle energy incident on the detector material.

Track profile was obtained as mentioned before and the range of certain particle track energy in the detector was measured using the relation

$$R = L\_{\text{eR}} + h\_{\text{R}} \tag{8}$$

where *L*eR is the track length just very close to the end of track *L*eR = *V*T*t*R, *V*<sup>T</sup> is the track etch rate and *h* is the removal thickness layer (*h* = *V*B*t*R), *t*<sup>R</sup> is the time needed to reach to the end of track.

#### *3.2.1 The results and discussion of TPT*

**Table 1** show that the *L*max depends on the energy of the incident particle while the *t*<sup>R</sup> not depends only on the energy of the incident particle but also on the etching rates, particularly the bulk etch rate *V*<sup>B</sup> which in turn controlled by the etching conditions; the concentration, and the temperature of the etching solution. The bulk etch rate *V*<sup>B</sup> was varying from 1.21 to 1.28 μm h�<sup>1</sup> with average value 1.25 � 0.04 <sup>μ</sup>m h�<sup>1</sup> . All values of *V*<sup>B</sup> were dependent on the etching conditions. The value of *L*max for the same energy is constant in the same matter. The range of the particle energy dependent on the density of medium. *<sup>R</sup>* <sup>¼</sup> <sup>Ð</sup> *<sup>R</sup>* <sup>0</sup> <sup>d</sup>*<sup>x</sup>* <sup>¼</sup> <sup>Ð</sup> <sup>0</sup> *T* d*x* <sup>d</sup>*<sup>T</sup>* d*T* = Ð *T* 0 d*T S T*ð Þ and *S T*ð Þ¼� <sup>d</sup>*<sup>x</sup>* <sup>d</sup>*<sup>T</sup>* d*T* = *In*ion where *T* is the kinetic energy of the particle, *n*ion is the number of electron ion pairs formed per unit path length, and *I* denotes the average energy needed to ionize an atom in the medium. The concentration of the solution and temperature are used to elucidate the path of the particles and have no effect along the path. The value of *L*max does not affect by increase in the concentration or in the temperature of the etching solution, while the time needed to reach to the end of track (*t*R) is change with change the condition of etching. The values of *L*max were 20.02, 17.60 and 12.32 μm with the energies of alpha particle 5.48, 5 and 4 MeV respectively. The result show that, the range of alpha energies 4, 5 and 5.48 MeV in CR39 were 19.88, 29.89 and 33.88 μm respectively. This value corresponds to the theoretical values shown in **Table 1**. After these regions, the track length starts to turn gradually into a circular path, and the track etch rate approaches the bulk etch rate (*V*<sup>T</sup> ≈ *V*B) and the track begins to change gradually to the spherical shape (**Figure 5**).

#### **3.3 The concentration of radon and the annual effective dose**

The equilibrium concentration of radon *C*eq determined from the track density by using the following relation

$$\mathbf{C\_{eq}} = \frac{\rho}{\mathbf{K}t\_{\circ'}}\tag{9}$$

Where *A* is the cross section area of cup (m<sup>2</sup>

The mass exhalation rate (Bq kg�<sup>1</sup> � <sup>h</sup>�<sup>1</sup>

*DOI: http://dx.doi.org/10.5772/intechopen.91899*

Where *M* is the mass of sample (kg). The annual effective dose *H* (μSv year�<sup>1</sup>

, and λ the decay constant for radon in h�<sup>1</sup>

*<sup>E</sup>*<sup>m</sup> <sup>¼</sup> CeqV<sup>λ</sup>

where, *C* in Bq m�<sup>3</sup> is the measured mean radon activity concentration in air, *F* is the indoor equilibrium factor between radon and its progeny (0.4),*T* is time

Thermal neutron activation analysis is used as the primary method for determining the element in any sample. This analysis is carried out inside the reactor with a flow of 3.31 � <sup>10</sup><sup>12</sup> n cm�<sup>2</sup> or more. Long-lived radio nuclides are determined using activation with thermal neutrons. First, the samples are filled in aluminum cups. With a 2-hour irradiation time, then re-encapsulate after irradiation and then measured after 4 days of cooling and a second time after 20 days of cooling, using a high-purity Germanium Mono-Germanium Spectrometer (HPGe) ray with a precision of 2.5 kV for the 60Co 1332.5 keV line, efficiently It is about 40% relative to the 3 � 3 "NaI reagent of the same line. Then gamma spectra are analyzed and then the

This method give the different element in air or in soil for example in Jazan region we can measure the different heavy element in air by using this technique.

The **Figures 6**–**9** are summarized the concentrations of heavy elements in Airport and Cady mall in PM10 and TSP samples which collected from Jazan city.

) and *D* is the dose conversion factor 9 nSv h�<sup>1</sup>

concentrations of different detected elements are estimated [10].

cup in m<sup>3</sup>

(7000 h year�<sup>1</sup>

**Figure 6.**

**47**

**3.4 Neutron activation analysis**

*3.4.1 The results and discussion of NAA*

*PM10—Airport zone: concentrations of heavy elements.*

following formula [4, 5, 8]:

*Natural Radioactive Decay*

), *V* is the effective volume of the

) in the samples is calculated using the

*<sup>M</sup>* (11)

) was calculated from the following relation.

/Bq m�<sup>3</sup> [3, 9].

.

*<sup>H</sup>* <sup>¼</sup> *<sup>C</sup>* � *<sup>D</sup>* � *<sup>F</sup>* � *<sup>T</sup>* <sup>¼</sup> <sup>25</sup>*:*2 C <sup>μ</sup>Sv year�<sup>1</sup> (12)

where *t*ef is the effective exposure time in hours and the calibration factor *K* of the SSNTDs (tracks cm�<sup>2</sup> day�<sup>1</sup> /Bq m�<sup>3</sup> ).

The surface exhalation rate (Bq m�<sup>1</sup> � <sup>h</sup>�<sup>1</sup> ) of the sample for the release of radon can be calculated by the formula exhalation rate [5, 7].

$$E\_{\rm a} = \frac{\mathbf{C\_{eq}} \mathbf{V} \lambda}{A} \tag{10}$$


#### **Table 1.**

*The maximum track length, range, the saturation time and bulk etch rate with different energy of alpha particle in CR39 detector.*

*3.2.1 The results and discussion of TPT*

1.25 � 0.04 <sup>μ</sup>m h�<sup>1</sup>

and *S T*ð Þ¼� <sup>d</sup>*<sup>x</sup>*

by using the following relation

the SSNTDs (tracks cm�<sup>2</sup> day�<sup>1</sup>

**Table 1.**

**46**

*particle in CR39 detector.*

The surface exhalation rate (Bq m�<sup>1</sup> � <sup>h</sup>�<sup>1</sup>

can be calculated by the formula exhalation rate [5, 7].

**Table 1** show that the *L*max depends on the energy of the incident particle while the *t*<sup>R</sup> not depends only on the energy of the incident particle but also on the etching rates, particularly the bulk etch rate *V*<sup>B</sup> which in turn controlled by the etching conditions; the concentration, and the temperature of the etching solution. The bulk

value of *L*max for the same energy is constant in the same matter. The range of the

number of electron ion pairs formed per unit path length, and *I* denotes the average energy needed to ionize an atom in the medium. The concentration of the solution and temperature are used to elucidate the path of the particles and have no effect along the path. The value of *L*max does not affect by increase in the concentration or in the temperature of the etching solution, while the time needed to reach to the end of track (*t*R) is change with change the condition of etching. The values of *L*max were 20.02, 17.60 and 12.32 μm with the energies of alpha particle 5.48, 5 and 4 MeV respectively. The result show that, the range of alpha energies 4, 5 and 5.48 MeV in CR39 were 19.88, 29.89 and 33.88 μm respectively. This value corresponds to the theoretical values shown in **Table 1**. After these regions, the track length starts to turn gradually into a circular path, and the track etch rate approaches the bulk etch rate (*V*<sup>T</sup> ≈ *V*B) and the track begins to change gradually to the spherical shape (**Figure 5**).

The equilibrium concentration of radon *C*eq determined from the track density

*<sup>C</sup>*eq <sup>¼</sup> *<sup>ρ</sup> Ktef*

/Bq m�<sup>3</sup>

Average *<sup>V</sup>*<sup>B</sup> 1.25 � 0.04 <sup>μ</sup>m h�<sup>1</sup>

where *t*ef is the effective exposure time in hours and the calibration factor *K* of

).

*<sup>E</sup>*<sup>a</sup> <sup>¼</sup> CeqV<sup>λ</sup>

**Energy** *E* **= 5.48 MeV** *E* **= 5 MeV** *E* **= 4 MeV** *L*max (μm) 20.02 17.60 12.32 *R* (μm) (theoretical values) 34.20 29.40 19.80 *R* (μm) experiment 33.88 29.89 19.88 *t*<sup>R</sup> (h) 11.00 9.75 6.00 *V*<sup>B</sup> (by *L*max) 1.28 1.21 1.25

*The maximum track length, range, the saturation time and bulk etch rate with different energy of alpha*

. All values of *V*<sup>B</sup> were dependent on the etching conditions. The

<sup>d</sup>*<sup>T</sup>* d*T* = *In*ion where *T* is the kinetic energy of the particle, *n*ion is the

<sup>0</sup> <sup>d</sup>*<sup>x</sup>* <sup>¼</sup> <sup>Ð</sup> <sup>0</sup> *T* d*x* <sup>d</sup>*<sup>T</sup>* d*T* =

) of the sample for the release of radon

*<sup>A</sup>* (10)

Ð *T* 0 d*T S T*ð Þ

(9)

etch rate *V*<sup>B</sup> was varying from 1.21 to 1.28 μm h�<sup>1</sup> with average value

particle energy dependent on the density of medium. *<sup>R</sup>* <sup>¼</sup> <sup>Ð</sup> *<sup>R</sup>*

*Recent Techniques and Applications in Ionizing Radiation Research*

**3.3 The concentration of radon and the annual effective dose**

Where *A* is the cross section area of cup (m<sup>2</sup> ), *V* is the effective volume of the cup in m<sup>3</sup> , and λ the decay constant for radon in h�<sup>1</sup> .

The mass exhalation rate (Bq kg�<sup>1</sup> � <sup>h</sup>�<sup>1</sup> ) in the samples is calculated using the following formula [4, 5, 8]:

$$E\_{\rm m} = \frac{\mathbf{C\_{eq}} \mathbf{V} \lambda}{M} \tag{11}$$

Where *M* is the mass of sample (kg).

The annual effective dose *H* (μSv year�<sup>1</sup> ) was calculated from the following relation.

$$H = \mathbb{C} \times D \times F \times T = \text{25.2 } \mathbb{C} \text{ (}\mu\text{Sv year}^{-1}\text{)}\tag{12}$$

where, *C* in Bq m�<sup>3</sup> is the measured mean radon activity concentration in air, *F* is the indoor equilibrium factor between radon and its progeny (0.4),*T* is time (7000 h year�<sup>1</sup> ) and *D* is the dose conversion factor 9 nSv h�<sup>1</sup> /Bq m�<sup>3</sup> [3, 9].

#### **3.4 Neutron activation analysis**

Thermal neutron activation analysis is used as the primary method for determining the element in any sample. This analysis is carried out inside the reactor with a flow of 3.31 � <sup>10</sup><sup>12</sup> n cm�<sup>2</sup> or more. Long-lived radio nuclides are determined using activation with thermal neutrons. First, the samples are filled in aluminum cups. With a 2-hour irradiation time, then re-encapsulate after irradiation and then measured after 4 days of cooling and a second time after 20 days of cooling, using a high-purity Germanium Mono-Germanium Spectrometer (HPGe) ray with a precision of 2.5 kV for the 60Co 1332.5 keV line, efficiently It is about 40% relative to the 3 � 3 "NaI reagent of the same line. Then gamma spectra are analyzed and then the concentrations of different detected elements are estimated [10].

This method give the different element in air or in soil for example in Jazan region we can measure the different heavy element in air by using this technique.

#### *3.4.1 The results and discussion of NAA*

The **Figures 6**–**9** are summarized the concentrations of heavy elements in Airport and Cady mall in PM10 and TSP samples which collected from Jazan city.

**Figure 6.** *PM10—Airport zone: concentrations of heavy elements.*

#### *Recent Techniques and Applications in Ionizing Radiation Research*

**Figure 7.** *PM10—Cady mall zone: concentrations of heavy elements.*

**Figures 6** and **7** were shown that the concentrations of heavy elements in Airport and Cady mall in PM10. The elements in TSP sample show in **Figures 8** and **9**.

vulcanized rubber in the presence of a stimulant. The vulcanization tonic currently used in industry is zinc oxide, which explains the source of zinc in tires and

The lowest concentrated elements were bromine and chromium in the Jizan region. The effects of bromine can be attributed to vehicle emissions. The contribution of cars to bromine emissions cannot be more than 5%. Chromium TSP concentration was also found from the Jazan mountainous district. Concentration may be harmful based on the findings of the Environmental Protection Agency [11], that continuous inhalation of about 0.8 ng m<sup>3</sup> of chromium increases the risk of

Basically, earth elements include Ce, Eu and La, while trace elements include Sc,

These concentrations differ from site to site according to the geography of the place and the data provided indicate that the concentration of iron, calcium, chromium and zinc in Jazan is relatively less than in other regions. The **Table 2** shows

To reduce the gamma ray background the hyper pure germanium detector is inserted inside a lead shield, through a hole in the bottom. The lead shield is internally lined with cadmium and copper layers. A layer of Cd (*z* = 48) and Cu are used, Cd is an effective filter for Pb-X rays, while Cu attenuates the Cd-X ray and

To reduce the noise from the thermal radiation in the crystal, the HPGe detector

is cooled with liquid nitrogen (77°K, 194°C) during its use. This reduces the leakage current generated by mobile carriers at room temperature and prevents voltage break down through the crystal. The HPGe Gamma-ray spectrometer

prevents personal exposure to the toxic cadmium **Figure 10**.

Th, Hf, Sb and Co. The maximum concentration of Sc and Co was noted in the Mountain neighborhood samples, while Th and Sb concentrations were found to be highest in the Airport zone. The maximum concentration of Hf was noted in the industrial zone samples, while the highest concentration of La, Ce and Eu was noted

brake pads.

**Figure 9.**

cancer by 1.0 <sup>10</sup><sup>6</sup>

*Natural Radioactive Decay*

*DOI: http://dx.doi.org/10.5772/intechopen.91899*

these differences.

**49**

%.

*TSP—an industrial zone: concentrations of heavy elements.*

in mountain neighborhood samples.

**3.5 Measurement of gamma ray**

By adopting the level of concentration of elements in the atmosphere as the ranking standard, barium, calcium, iron and zinc elements were found to be the most dominant elements in the Jazan region of Saudi Arabia. It was observed that the concentration depends on the study areas, as the industrial regions had the highest concentration of barium, iron, and zinc, whereas the market areas had the lowest concentration, especially barium and calcium. Barium concluded that the main source of barium traces is car paints. It was also found that the concentration of zinc traces in the airport area and in the industrial zone samples. The main sources of zinc impacts in Jizan are tire wear, brake wear and exhaust emissions. Therefore, we can ensure that zinc emissions are due to industrial processes, especially those related with tire wear and wear. Tires and brake pads are made of

**Figure 8.** *TSP—Mountain neighborhood zone: concentrations of heavy elements.*

*Natural Radioactive Decay DOI: http://dx.doi.org/10.5772/intechopen.91899*

**Figure 9.** *TSP—an industrial zone: concentrations of heavy elements.*

vulcanized rubber in the presence of a stimulant. The vulcanization tonic currently used in industry is zinc oxide, which explains the source of zinc in tires and brake pads.

The lowest concentrated elements were bromine and chromium in the Jizan region. The effects of bromine can be attributed to vehicle emissions. The contribution of cars to bromine emissions cannot be more than 5%. Chromium TSP concentration was also found from the Jazan mountainous district. Concentration may be harmful based on the findings of the Environmental Protection Agency [11], that continuous inhalation of about 0.8 ng m<sup>3</sup> of chromium increases the risk of cancer by 1.0 <sup>10</sup><sup>6</sup> %.

Basically, earth elements include Ce, Eu and La, while trace elements include Sc, Th, Hf, Sb and Co. The maximum concentration of Sc and Co was noted in the Mountain neighborhood samples, while Th and Sb concentrations were found to be highest in the Airport zone. The maximum concentration of Hf was noted in the industrial zone samples, while the highest concentration of La, Ce and Eu was noted in mountain neighborhood samples.

These concentrations differ from site to site according to the geography of the place and the data provided indicate that the concentration of iron, calcium, chromium and zinc in Jazan is relatively less than in other regions. The **Table 2** shows these differences.

#### **3.5 Measurement of gamma ray**

To reduce the gamma ray background the hyper pure germanium detector is inserted inside a lead shield, through a hole in the bottom. The lead shield is internally lined with cadmium and copper layers. A layer of Cd (*z* = 48) and Cu are used, Cd is an effective filter for Pb-X rays, while Cu attenuates the Cd-X ray and prevents personal exposure to the toxic cadmium **Figure 10**.

To reduce the noise from the thermal radiation in the crystal, the HPGe detector is cooled with liquid nitrogen (77°K, 194°C) during its use. This reduces the leakage current generated by mobile carriers at room temperature and prevents voltage break down through the crystal. The HPGe Gamma-ray spectrometer

**Figures 6** and **7** were shown that the concentrations of heavy elements in Airport and Cady mall in PM10. The elements in TSP sample show in **Figures 8** and **9**. By adopting the level of concentration of elements in the atmosphere as the ranking standard, barium, calcium, iron and zinc elements were found to be the most dominant elements in the Jazan region of Saudi Arabia. It was observed that the concentration depends on the study areas, as the industrial regions had the highest concentration of barium, iron, and zinc, whereas the market areas had the lowest concentration, especially barium and calcium. Barium concluded that the main source of barium traces is car paints. It was also found that the concentration of zinc traces in the airport area and in the industrial zone samples. The main sources of zinc impacts in Jizan are tire wear, brake wear and exhaust emissions. Therefore, we can ensure that zinc emissions are due to industrial processes, especially those related with tire wear and wear. Tires and brake pads are made of

**Figure 7.**

**Figure 8.**

**48**

*TSP—Mountain neighborhood zone: concentrations of heavy elements.*

*PM10—Cady mall zone: concentrations of heavy elements.*

*Recent Techniques and Applications in Ionizing Radiation Research*

#### *Recent Techniques and Applications in Ionizing Radiation Research*


#### **Table 2.**

*Comparison of the concentration ranges of some elements in Jazan (present work) and other places in the world.*

consists of a detector, a pulse processing electronic unit, and an output device such as a counter, multi-channel analyzer (MCA). A diagram of a basic radiation detection system is **Figure 11**.

The coarse and fine gain controls of the spectroscopy amplifier, it's differentiating and integrating time constants and all other controls were adjusted to obtain the best energy resolution and good linearity of the spectrometer over a wide range the input voltages. After selecting the optimum set up, the resolving power (resolution) of the spectrometer was found to be 1.92 KeV for 1332 KeV gamma ray line of the 60Co.

The gamma ray spectrometer system was calibrated by applying different standard gamma emitters'sources. These include 137Cs (661.66 keV), 60Co (1173.23, 1332.5 keV), 40K (1460.8 keV) and 226Ra which is most favorable for calibration, since its spectrum covers a wide energy range from 0.186 to 2.45 MeV.

To measure gamma ray in any sample must folded and placed container for 1 month to allow radioactive equilibrium to be reached (secular equilibrium) This step ensured that radon gas and its daughters remain in the sample.

The gamma ray spectra of sample accumulate for at least 24 hours, and then analyze to detect the gamma ray energies due to uranium, thorium and their daughters, and due to potassium, and then the counting rate for each gamma transition was determined.

The radioactive decay series of 238U and 232Th are complex and produces alpha, beta, and gamma radiation. **Figures 12** and **13** show the important isotopes in the decay series, indicates whether the primary decay mode is via alpha or beta emission, and gives the half-life.

> available and simple, as they are characterized by accuracy and high sensitivity, so it can be relied upon to determine the concentration of radioactive materials and doses that determine the places of pollution. These methods contribute to preserving the environment, by identifying the places of pollution, whether by radiation or by heavy materials. Measuring heavy materials is an important technology in

**Figure 10.**

**Figure 11.**

**51**

*High purity germanium detector.*

*Natural Radioactive Decay*

*DOI: http://dx.doi.org/10.5772/intechopen.91899*

*Block diagram of gamma ray spectrometer.*

#### **3.6 Conclusions**

This chapter presented the methods of decay for alpha, beta, and gamma, as well as showed the best methods for measuring both alpha and gamma, which are

**Figure 10.** *High purity germanium detector.*

consists of a detector, a pulse processing electronic unit, and an output device such as a counter, multi-channel analyzer (MCA). A diagram of a basic radiation detec-

*Comparison of the concentration ranges of some elements in Jazan (present work) and other places in the*

**Local Concentration (ng m<sup>3</sup>**

*Recent Techniques and Applications in Ionizing Radiation Research*

Jazan city 26058.8–66998.4 7003.8–27798.7 12955.1–41069.7 61.14–

North Egypt Nd 1430–22,230 50–146,930 10–

Upper-Egypt 42713.4380447.75 2022.2321,420 12327.125628.3 59.9–

<sup>11</sup>–2.5 <sup>10</sup><sup>5</sup> 77.4–2.9 105 0.0–1.5 104 0.0–

since its spectrum covers a wide energy range from 0.186 to 2.45 MeV.

step ensured that radon gas and its daughters remain in the sample.

The coarse and fine gain controls of the spectroscopy amplifier, it's differentiating and integrating time constants and all other controls were adjusted to obtain the best energy resolution and good linearity of the spectrometer over a wide range the input voltages. After selecting the optimum set up, the resolving power (resolution) of the spectrometer was found to be 1.92 KeV for 1332 KeV gamma ray line of the 60Co. The gamma ray spectrometer system was calibrated by applying different standard gamma emitters'sources. These include 137Cs (661.66 keV), 60Co (1173.23, 1332.5 keV), 40K (1460.8 keV) and 226Ra which is most favorable for calibration,

**Ca Fe Zn Cr Co**

Nd 747–5967 20–1049 3.5–12 Nd Bilos et al.

171–245 245–348 64–641 7.1–18 Nd Harrinson

1918 666 231 5.7 Nd Sweet et al.

Nd 3710 <103 10–30 Nd Lantzy and

**) References**

6.9– 12.1

7.3– 12.24

0.8– 1.6

Present work

Monged [12]

Quiterioa et al. [13]

[14]

et al. [15]

[16]

Mackenzie [17]

1–20 EL-Araby et al. [10]

91.9

500

101.55

8678

To measure gamma ray in any sample must folded and placed container for 1 month to allow radioactive equilibrium to be reached (secular equilibrium) This

The gamma ray spectra of sample accumulate for at least 24 hours, and then analyze to detect the gamma ray energies due to uranium, thorium and their daughters, and due to potassium, and then the counting rate for each gamma

The radioactive decay series of 238U and 232Th are complex and produces alpha, beta, and gamma radiation. **Figures 12** and **13** show the important isotopes in the decay series, indicates whether the primary decay mode is via alpha or beta emis-

This chapter presented the methods of decay for alpha, beta, and gamma, as well

as showed the best methods for measuring both alpha and gamma, which are

tion system is **Figure 11**.

Santa Cruz, Brazil

La Plata, Argentina

East St. Louis, USA

USA and European Cities

**Table 2.**

*world.*

Birmingham, UK

transition was determined.

sion, and gives the half-life.

**3.6 Conclusions**

**50**

**Figure 11.** *Block diagram of gamma ray spectrometer.*

available and simple, as they are characterized by accuracy and high sensitivity, so it can be relied upon to determine the concentration of radioactive materials and doses that determine the places of pollution. These methods contribute to preserving the environment, by identifying the places of pollution, whether by radiation or by heavy materials. Measuring heavy materials is an important technology in

#### *Recent Techniques and Applications in Ionizing Radiation Research*

**Figure 12.** *The Uranium-238 decay chain.*

determining the whereabouts of uranium and its daughter. This technology also contributes to reducing environmental pollution by harmful heavy materials.

• The analysis of the samples enabled the author to arrive at the conclusion that maximum concentration of PM10 and TSP aerosols in Jazan city occurs during

• When literature values for the concentration of heavy metals were compared with other areas, it was concluded that Jazan city had relatively lower concentration with respect to North Egypt and Santa Cruz industrial district. The results also revealed that the difference in heavy metal concentrations was much pronounced when non-polluted zones were compared with polluted

• It was concluded that Jazan city PM10 and TSP aerosols are mainly rich in calcium, barium, zinc, and iron; all of which are as a result of anthropogenic

• The concentration of zinc and Barium was found to be highest in the airport area, while iron and calcium were found to be highly concentrated in Cady

Having covered the concentration of heavy metals in the atmosphere of four locations in Jazan city, and the dangers associated with high concentration of such

metals ascertained, a number of recommendations were made as follows.

Mall and the Mountain neighborhood respectively.

March.

*The Thorium-232 decay chain.*

*Natural Radioactive Decay*

*DOI: http://dx.doi.org/10.5772/intechopen.91899*

**Figure 13.**

zones.

activities.

**53**

The result show that the best method to determination of bulk etch rate *V*<sup>B</sup> is by *L*max method; it is the faster and easier than weight method. The range of alpha particle is measured by track profile method (TPT). The measured range of alpha particles was very close to the theoretical values of the range. The track profile method is useful to determine the different parameters of track.

This chapter has successfully evaluated the concentration of heavy metals in the atmosphere of the Mountain Neighborhood, Airport, Cady Mall and Industrial zones and established a number of conclusions. For instance, it was found that all the sampled specimens were enriched with both zinc and calcium. However, barium was only found in the Airport, Mountain Neighborhood and Industrial zones. Ultimately, a number of conclusions based on the findings have been outlined below.

*Natural Radioactive Decay DOI: http://dx.doi.org/10.5772/intechopen.91899*

**Figure 13.** *The Thorium-232 decay chain.*


Having covered the concentration of heavy metals in the atmosphere of four locations in Jazan city, and the dangers associated with high concentration of such metals ascertained, a number of recommendations were made as follows.

determining the whereabouts of uranium and its daughter. This technology also contributes to reducing environmental pollution by harmful heavy materials.

method is useful to determine the different parameters of track.

*Recent Techniques and Applications in Ionizing Radiation Research*

below.

**52**

**Figure 12.**

*The Uranium-238 decay chain.*

The result show that the best method to determination of bulk etch rate *V*<sup>B</sup> is by *L*max method; it is the faster and easier than weight method. The range of alpha particle is measured by track profile method (TPT). The measured range of alpha particles was very close to the theoretical values of the range. The track profile

This chapter has successfully evaluated the concentration of heavy metals in the

atmosphere of the Mountain Neighborhood, Airport, Cady Mall and Industrial zones and established a number of conclusions. For instance, it was found that all the sampled specimens were enriched with both zinc and calcium. However, barium was only found in the Airport, Mountain Neighborhood and Industrial zones. Ultimately, a number of conclusions based on the findings have been outlined

#### *Recent Techniques and Applications in Ionizing Radiation Research*

It is recommended that green belts be designed around different cities in order to reduce the level of concentration of aerosols in the atmosphere. In addition, environmental regulations should be put forward and their effectiveness be ensured through strict monitoring of air pollution levels. The use of transport and construction machinery that increase emission of aerosols should be minimized whenever possible. Finally the author suggests that a thorough evaluation should be carried out before any industrial project is implemented in order to ascertain its level of pollution as well as its compatibility within the framework of sustainable environment.

**References**

[1] Morison I. Introduction to

*Natural Radioactive Decay*

Astronomy and Cosmology. Southern Gate, Chichester, West Sussex, United Kingdom: John Wiley & Sons Ltd; 2008

*DOI: http://dx.doi.org/10.5772/intechopen.91899*

atmospheric heavy metal deposition in Egypt by using neutron activation analysis. Applied Radiation and Isotopes. 2011;**69**:1506-1511

[11] Environmental Protection Agency EPA. Air Toxics Website. 2003. Available from: http://www.epa.gov/

[12] Monged MHE. Assessment of Ambient Gamma Radiation and Chemical Pollutants in Upper Egypt's Atmosphere. [PhD thesis] Chemistry Department, Faculty of Science, Ain

[13] Quiterioa SL, da Silvaa CRS, Arbillaa G, Escaleira V. Metals in airborne particulate matter in the industrial district of Santa Cruz, Rio de Janerio, in an annual period. AE

International-Central & South America, Atmospheric Environment. 2004;**38**:

[14] Bilos C, Colombo JC, Skorupka CN, Rodrigues Presa J. Sources, distribution and variability if airborne trace metals in La Plata City area, Argentina. Environmental Pollution. 2001;**111**:

[15] Harrinson RM, Smith DJT, Luhana L. Source apportionment of atmospheric polycyclic aromatic hydrocarbons collected from an urban

location in Birmingham, UK.

[16] Sweet CW, Vermette SJ, Landsberg S. Sources of toxic trace elements in in urban air in Illinois. Environmental Science and Technology.

[17] Lantzy RJ, Mackenzie FT.

Atmospheric trace metals: Global cycles and assessment of man's impact.

Geochimica Cosmochimica Acta. 1979;**43**:

1993;**27**(12):2502-2510

511-525

1996;**30**:825-832

Environmental Science and Technology.

Shams University. 2009

321-331

149-158

ttn/atw/hlthef/S

[2] WHO, Handbook. World Handbook

on Indoor Radon. World Health

[3] ICRP. Radiological protection in medicine. ICRP Publication 105. Annals

[4] EL-Araby EH. Direct measurement of the radioactive radon gas activity in water in Saudi Arabia. AIP Conference Proceedings. 2018;**1976**(1):020019

Abo-Elmagd M. Measurement of radon levels in water and the associated health hazards in Jazan—Saudi Arabia. Journal of Radiation Research and Applied

parameterization of CR-39 longitudinal track depth. Radiation Measurements.

[5] EL-Araby EH, Soliman HA,

Science. 2019;**12**(1):31-36

2012;**47**:67-72

**167**:44-48

[6] Azooz AA, AL-Nia'emi SHS, Al-Jubbori MA. Empirical

[7] Chen J, Whyte J, Ford K. An overview of radon research in Canada. Radiation Protection Dosimetry. 2015;

[8] Singh K, Sengupta D, Prasad R. Radon exhalation rate and uranium estimation in rock samples from Bihar uranium and copper mines using the SSNTD technique. Applied Radiation

and Isotopes. 1999;**51**:107-113

Publication Annex B; 2008

EL-Desouky TM, Diab HM, Mohseen MM. Assessment of

**55**

[9] UNSCEAR. United Nations Scientific Committee on the Effects of Atomic Radiation Sources and Effects of Ionizing Radiation. United Nations

[10] EL-Araby EH, Abd El-wahab MM,

Organization. 2009:94

of the ICRP. 2007;**37**(5)

### **Author details**

Entesar H. Elaraby Faculty of Science, Jazan University, Kingdom of Saudi Arabia

\*Address all correspondence to: entesar.araby@gmail.com

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

### **References**

It is recommended that green belts be designed around different cities in order to reduce the level of concentration of aerosols in the atmosphere. In addition, environmental regulations should be put forward and their effectiveness be ensured through strict monitoring of air pollution levels. The use of transport and construction machinery that increase emission of aerosols should be minimized whenever possible. Finally the author suggests that a thorough evaluation should be carried out before any industrial project is implemented in order to ascertain its level of pollution as well as its compatibility within the framework of sustainable

*Recent Techniques and Applications in Ionizing Radiation Research*

environment.

**Author details**

Entesar H. Elaraby

**54**

Faculty of Science, Jazan University, Kingdom of Saudi Arabia

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

\*Address all correspondence to: entesar.araby@gmail.com

provided the original work is properly cited.

[1] Morison I. Introduction to Astronomy and Cosmology. Southern Gate, Chichester, West Sussex, United Kingdom: John Wiley & Sons Ltd; 2008

[2] WHO, Handbook. World Handbook on Indoor Radon. World Health Organization. 2009:94

[3] ICRP. Radiological protection in medicine. ICRP Publication 105. Annals of the ICRP. 2007;**37**(5)

[4] EL-Araby EH. Direct measurement of the radioactive radon gas activity in water in Saudi Arabia. AIP Conference Proceedings. 2018;**1976**(1):020019

[5] EL-Araby EH, Soliman HA, Abo-Elmagd M. Measurement of radon levels in water and the associated health hazards in Jazan—Saudi Arabia. Journal of Radiation Research and Applied Science. 2019;**12**(1):31-36

[6] Azooz AA, AL-Nia'emi SHS, Al-Jubbori MA. Empirical parameterization of CR-39 longitudinal track depth. Radiation Measurements. 2012;**47**:67-72

[7] Chen J, Whyte J, Ford K. An overview of radon research in Canada. Radiation Protection Dosimetry. 2015; **167**:44-48

[8] Singh K, Sengupta D, Prasad R. Radon exhalation rate and uranium estimation in rock samples from Bihar uranium and copper mines using the SSNTD technique. Applied Radiation and Isotopes. 1999;**51**:107-113

[9] UNSCEAR. United Nations Scientific Committee on the Effects of Atomic Radiation Sources and Effects of Ionizing Radiation. United Nations Publication Annex B; 2008

[10] EL-Araby EH, Abd El-wahab MM, EL-Desouky TM, Diab HM, Mohseen MM. Assessment of

atmospheric heavy metal deposition in Egypt by using neutron activation analysis. Applied Radiation and Isotopes. 2011;**69**:1506-1511

[11] Environmental Protection Agency EPA. Air Toxics Website. 2003. Available from: http://www.epa.gov/ ttn/atw/hlthef/S

[12] Monged MHE. Assessment of Ambient Gamma Radiation and Chemical Pollutants in Upper Egypt's Atmosphere. [PhD thesis] Chemistry Department, Faculty of Science, Ain Shams University. 2009

[13] Quiterioa SL, da Silvaa CRS, Arbillaa G, Escaleira V. Metals in airborne particulate matter in the industrial district of Santa Cruz, Rio de Janerio, in an annual period. AE International-Central & South America, Atmospheric Environment. 2004;**38**: 321-331

[14] Bilos C, Colombo JC, Skorupka CN, Rodrigues Presa J. Sources, distribution and variability if airborne trace metals in La Plata City area, Argentina. Environmental Pollution. 2001;**111**: 149-158

[15] Harrinson RM, Smith DJT, Luhana L. Source apportionment of atmospheric polycyclic aromatic hydrocarbons collected from an urban location in Birmingham, UK. Environmental Science and Technology. 1996;**30**:825-832

[16] Sweet CW, Vermette SJ, Landsberg S. Sources of toxic trace elements in in urban air in Illinois. Environmental Science and Technology. 1993;**27**(12):2502-2510

[17] Lantzy RJ, Mackenzie FT. Atmospheric trace metals: Global cycles and assessment of man's impact. Geochimica Cosmochimica Acta. 1979;**43**: 511-525

**Chapter 5**

**Abstract**

**1. Introduction**

**57**

Radon in Foods

factor for Rn-222, and Ra-226 for all types.

*Tayseer I. Al-Naggar and Doaa H. Shabaan*

This chapter show the natural of radioactivity as alpha particle which produce from decaying of radium to radon so in this chapter describe the radon in some types of household food (coffee, tea, powder milk, rice, flour, cornstarch, and powder coconut) and different types of salt by using Solid State Nuclear Track Detectors (SSNTD), were analyzed by closed-can technique (CR-39). Many food items contain natural sources of salt. Salt analysis is very important due to its high consumption by the population and for its medicinal use. Analysis the concentrations of Radon-222 and Radium-226 for different types of household foods samples are very substantial for realizing the comparative contributions of specific substances to the whole radon content set within the human body. After study it is found that the average values of annual effective dose in mSv/y are within the recommended limit of ICRP values except its values for cornstarch and sugar are relatively high, and there are a wide range of variations in the values of transfer

**Keywords:** radon, CR-39, food, radiation hazards, closed can technique

Uranium occurs naturally in low concentrations (a few parts per million) in soil,

rock, surface water, and groundwater. It is a relatively reactive element which combines with non–metals such as oxygen, sulfur, chlorine, fluorine, phosphorus, and bromine [1]. Naturally, Uranium exists as three isotopes 234U, 235U and 238U with a relative abundance of 0.0055, 0.720 and 99.29%, respectively [2]. Uranium and its compounds are carcinogenic and highly toxic, which causes acute kidney failure and death in high concentrations as well as brain, liver and heart diseases [2]. Uranium ore is relatively harmless, as long as it remains outside of the body. Once ingested uranium is highly toxic and attacks the inner organs such as kidneys, lungs and heart. Uranium has been repeatedly claimed to be the cause of cancer, leukemia and other health effects. Health effects from external exposure are limited to skin contact and uranium object would have to stay in direct skin contact for more than 250 h. If this will happen then a person will be susceptible to skin cancer [3]. Uranium daughters (Ra-226 and Rn-222) are mainly have a major health risk. The measurements of radon and radium concentrations in foods are main for the health safety. Radium-226 in the environment is broadly spreading, and usually presented in several concentrations in soils, water, foods, sediments and rocks. However, the chemical manner of radium is as like as calcium, therefore radium absorbed to blood from lungs or gastrointestinal tract (GI-tract) or follows the manner of calcium and is mainly deposited in bone [4]. Radon-222 is a progeny product of radium-226 which is called alpha gas emitter. Its half-life of 3.82 days

## **Chapter 5** Radon in Foods

*Tayseer I. Al-Naggar and Doaa H. Shabaan*

#### **Abstract**

This chapter show the natural of radioactivity as alpha particle which produce from decaying of radium to radon so in this chapter describe the radon in some types of household food (coffee, tea, powder milk, rice, flour, cornstarch, and powder coconut) and different types of salt by using Solid State Nuclear Track Detectors (SSNTD), were analyzed by closed-can technique (CR-39). Many food items contain natural sources of salt. Salt analysis is very important due to its high consumption by the population and for its medicinal use. Analysis the concentrations of Radon-222 and Radium-226 for different types of household foods samples are very substantial for realizing the comparative contributions of specific substances to the whole radon content set within the human body. After study it is found that the average values of annual effective dose in mSv/y are within the recommended limit of ICRP values except its values for cornstarch and sugar are relatively high, and there are a wide range of variations in the values of transfer factor for Rn-222, and Ra-226 for all types.

**Keywords:** radon, CR-39, food, radiation hazards, closed can technique

#### **1. Introduction**

Uranium occurs naturally in low concentrations (a few parts per million) in soil, rock, surface water, and groundwater. It is a relatively reactive element which combines with non–metals such as oxygen, sulfur, chlorine, fluorine, phosphorus, and bromine [1]. Naturally, Uranium exists as three isotopes 234U, 235U and 238U with a relative abundance of 0.0055, 0.720 and 99.29%, respectively [2]. Uranium and its compounds are carcinogenic and highly toxic, which causes acute kidney failure and death in high concentrations as well as brain, liver and heart diseases [2]. Uranium ore is relatively harmless, as long as it remains outside of the body. Once ingested uranium is highly toxic and attacks the inner organs such as kidneys, lungs and heart. Uranium has been repeatedly claimed to be the cause of cancer, leukemia and other health effects. Health effects from external exposure are limited to skin contact and uranium object would have to stay in direct skin contact for more than 250 h. If this will happen then a person will be susceptible to skin cancer [3].

Uranium daughters (Ra-226 and Rn-222) are mainly have a major health risk. The measurements of radon and radium concentrations in foods are main for the health safety. Radium-226 in the environment is broadly spreading, and usually presented in several concentrations in soils, water, foods, sediments and rocks. However, the chemical manner of radium is as like as calcium, therefore radium absorbed to blood from lungs or gastrointestinal tract (GI-tract) or follows the manner of calcium and is mainly deposited in bone [4]. Radon-222 is a progeny product of radium-226 which is called alpha gas emitter. Its half-life of 3.82 days

with alpha energy 5.49 Mev. Radon progenies are Po-218 and Po-214 emit alpha particles. These daughters' yields are hard and have a trend to relate themselves to aerosols in around air. When human respire or inhale radon and its progenies along with the normal air, most of the radon is exhaled, its progenies become record to the internal walls and membranes of our respiratory system and continue producing steady damage because of their alpha activity [5, 6].

Radiation contamination which are existing in water and soil can be transported by the food chain to humans and animals [6, 7]. When the human are eating plants, meat of animals or drinking any fluids (tea, coffee, water, and juice), he can be contaminated with different radioactive isotopes (Ra-226, Rn-222, U-238, etc). Plants contain radioactive isotopes initiating from the soil, that absorbed it with other natural substances. Also drinking water and fluids can contain low dose. Air which human breath it, is the primary source of radioactive dose that enter the human body, and as well as the main source of radon that found in the earth's atmosphere generated by the automatic decomposition of uranium [6, 8]. The breathing of radon radioactive progenies with ambient air can caused kidney infections, lung cancer, and skin.

#### **2. Materials and methods**

#### **2.1 The samples**

Through current work, 24 samples from different types of household foods were collected from Egyptian markets which these foods are considered the daily diet of Egypt residents. These household foods are (coffee, tea, powder milk, rice, flour, cornstarch, and powder coconut, salt) were analyzed by closed-can technique (CR-39). Fifty grams from each sample was put in plastic can as its natural form without any process, a piece of CR-39 manufactured by TASTRACK. Analysis System, Ltd., UK:TASTRACK, which has dimensions (1 � 1) cm was fixed well in the cover of plastic can in front of the sample, after that CR-39 detector was covered by a piece of sponge to prevent thoron-220 from the arrival to CR-39 detector. Plastic can was closed well by its cover and was left for 1 month as exposure time, closed can techniques produced in **Figure 1**. CR-39 polymer detector registers alpha particles which emitted by decay of radium to radon gas as tracks. After the exposure time, CR-39 detectors were assembled from cans and chemically etched in NaOH solution 6.25 M at 70°C to enlarge and appear the alpha tracks through time equal 8 h [9]. After that, CR-39 detectors were washed by purified water and dried well in air. Numbers of tracks for each detector were counted by an optical microscope at a magnification of 400�. Background of CR-39 detectors were registered in this study and subtracted from the net tracks for each sample.

#### **2.2 Theoretical concepts**

The activity concentration of radon (Bq/m<sup>3</sup> ) can be calculated by using the following equation [10–12]:

$$\mathbf{C} = \frac{\rho}{K.T} \tag{1}$$

The effective radium content CRa (Bq/kg) can be found from the equation [1,12]:

where *ρ* is the counted track density, h is the distance between the detector and the top of the sample, k is the calibration factor of the CR-39 detector, M is the mass of the sample, and Te is the effective exposure time which can be determined by the

*Te* <sup>¼</sup> *<sup>T</sup>* � <sup>1</sup> � *<sup>e</sup>*�*λRaT*

The radon exhalation rate can be determined from the relation reported by

*<sup>E</sup>* <sup>¼</sup> *CRnλ<sup>V</sup> ATe*

The annual effective dose (Eeff) (mSv/y) can be obtained using the equation [13]:

where H is the occupancy factor which is equal to (0.8), T is the time in hours in

Transfer factor (TF) for radionuclides (Rn-222, and Ra-226) in household foods:

a year (T = 8760 h/y), and D is the dose conversion factor which is equal to

)) [14].

where T is the exposure time, and *λRn* decay constant for radon (h�<sup>1</sup>

*λRn*

), V is volume of the can (m<sup>3</sup>

*kTeM* (2)

h), *λRn* decay constant for radon (h�<sup>1</sup>

*Eeff* ¼ *C* � *F* � *H* � *T* � *D* (5)

).

(3)

(4)

), A is

).

*CRa* <sup>¼</sup> *<sup>ρ</sup>hA*

following equation.

where *CRn* is radon exposure (Bqm�<sup>3</sup>

*Closed can technique of CR-39 with household foods samples.*

surface area of water samples (m<sup>2</sup>

(9 � <sup>10</sup>�<sup>6</sup> (m Sv)/(Bq h m�<sup>3</sup>

[1, 12]:

**59**

**Figure 1.**

*Radon in Foods*

*DOI: http://dx.doi.org/10.5772/intechopen.93123*

where k is the calibration factor has unit (Bq/m<sup>3</sup> d)/(track/cm<sup>2</sup> ), *ρ* is track density (number of tracks/cm<sup>2</sup> ) and T is exposure time (in days). The calibration factor value (0.20 Bq/m<sup>3</sup> d)/(track/cm<sup>2</sup> ) as reported at many studies [10–12].

with alpha energy 5.49 Mev. Radon progenies are Po-218 and Po-214 emit alpha particles. These daughters' yields are hard and have a trend to relate themselves to aerosols in around air. When human respire or inhale radon and its progenies along with the normal air, most of the radon is exhaled, its progenies become record to the internal walls and membranes of our respiratory system and continue producing

Radiation contamination which are existing in water and soil can be transported by the food chain to humans and animals [6, 7]. When the human are eating plants, meat of animals or drinking any fluids (tea, coffee, water, and juice), he can be contaminated with different radioactive isotopes (Ra-226, Rn-222, U-238, etc). Plants contain radioactive isotopes initiating from the soil, that absorbed it with other natural substances. Also drinking water and fluids can contain low dose. Air which human breath it, is the primary source of radioactive dose that enter the human body, and as well as the main source of radon that found in the earth's atmosphere generated by the automatic decomposition of uranium [6, 8]. The breathing of radon radioactive progenies with ambient air can caused kidney infec-

Through current work, 24 samples from different types of household foods were collected from Egyptian markets which these foods are considered the daily diet of Egypt residents. These household foods are (coffee, tea, powder milk, rice, flour, cornstarch, and powder coconut, salt) were analyzed by closed-can technique (CR-39). Fifty grams from each sample was put in plastic can as its natural form without any process, a piece of CR-39 manufactured by TASTRACK. Analysis System, Ltd., UK:TASTRACK, which has dimensions (1 � 1) cm was fixed well in the cover of plastic can in front of the sample, after that CR-39 detector was covered by a piece of sponge to prevent thoron-220 from the arrival to CR-39 detector. Plastic can was closed well by its cover and was left for 1 month as exposure time, closed can techniques produced in **Figure 1**. CR-39 polymer detector registers alpha particles which emitted by decay of radium to radon gas as tracks. After the exposure time, CR-39 detectors were assembled from cans and chemically etched in NaOH solution 6.25 M at 70°C to enlarge and appear the alpha tracks through time equal 8 h [9]. After that, CR-39 detectors were washed by purified water and dried well in air. Numbers of tracks for each detector were counted by an optical microscope at a magnification of 400�. Background of CR-39 detectors were registered

) can be calculated by using the

*<sup>K</sup>:<sup>T</sup>* (1)

), *ρ* is track

d)/(track/cm<sup>2</sup>

) as reported at many studies [10–12].

) and T is exposure time (in days). The calibration

in this study and subtracted from the net tracks for each sample.

*<sup>C</sup>* <sup>¼</sup> *<sup>ρ</sup>*

The activity concentration of radon (Bq/m<sup>3</sup>

where k is the calibration factor has unit (Bq/m<sup>3</sup>

d)/(track/cm<sup>2</sup>

steady damage because of their alpha activity [5, 6].

*Recent Techniques and Applications in Ionizing Radiation Research*

tions, lung cancer, and skin.

**2. Materials and methods**

**2.2 Theoretical concepts**

following equation [10–12]:

density (number of tracks/cm<sup>2</sup>

factor value (0.20 Bq/m<sup>3</sup>

**58**

**2.1 The samples**

**Figure 1.** *Closed can technique of CR-39 with household foods samples.*

The effective radium content CRa (Bq/kg) can be found from the equation [1,12]:

$$\mathbf{C}\_{Ra} = \frac{\rho hA}{kT\_eM} \tag{2}$$

where *ρ* is the counted track density, h is the distance between the detector and the top of the sample, k is the calibration factor of the CR-39 detector, M is the mass of the sample, and Te is the effective exposure time which can be determined by the following equation.

$$T\_{\epsilon} = T - \frac{\left(\mathbf{1} - e^{-\lambda\_{\text{Re}}T}\right)}{\lambda\_{\text{Re}}} \tag{3}$$

where T is the exposure time, and *λRn* decay constant for radon (h�<sup>1</sup> ).

The radon exhalation rate can be determined from the relation reported by [1, 12]:

$$E = \frac{C\_{Rn}\lambda V}{AT\_{\varepsilon}}\tag{4}$$

where *CRn* is radon exposure (Bqm�<sup>3</sup> h), *λRn* decay constant for radon (h�<sup>1</sup> ), A is surface area of water samples (m<sup>2</sup> ), V is volume of the can (m<sup>3</sup> ).

The annual effective dose (Eeff) (mSv/y) can be obtained using the equation [13]:

$$E\_{\rm eff} = C \times F \times H \times T \times D \tag{5}$$

where H is the occupancy factor which is equal to (0.8), T is the time in hours in a year (T = 8760 h/y), and D is the dose conversion factor which is equal to (9 � <sup>10</sup>�<sup>6</sup> (m Sv)/(Bq h m�<sup>3</sup> )) [14].

Transfer factor (TF) for radionuclides (Rn-222, and Ra-226) in household foods:

Concentrations of radionuclides in foods which are grown in the soil depend on the concentrations of theses radionuclides in dry soils. Transfer factor (TF) can be calculated by the following equation [8, 15, 16]:

$$TF = \frac{\text{C}\_{food} \left( \text{Bq } \text{kg}^{-1} dry \text{ weight} \right)}{\text{C}\_{soil} \left( \text{Bq } \text{kg}^{-1} dry \text{ weight} \right)} \tag{6}$$

where *Cfoods* is the activity concentration of 226Ra or 222Rn in dry weight of foods samples and *Csoil* is the average activity concentration of radionuclide (226Ra or 222Rn) in dry weight of soil samples.

#### **3. The concentration of radon**

#### **3.1 The radon in salt**

The variation of radon concentration with types of salt is shown in **Figure 2**. It is found that the radon concentration in local salt has range between 335.46 and 558.94 Bq m�<sup>3</sup> with average 447.15 Bq m�<sup>3</sup> , and in imported salt has range between 223.58 and 335.36 Bq m�<sup>3</sup> with average 279.47 Bq m�<sup>3</sup> but in rock salt has range between 484.42 and 633.47 Bq m�<sup>3</sup> with average 549.63 Bq m�<sup>3</sup> as showed in (**Table 1**), It is shown that the concentration in rock salt is higher than the recommended value 400 Bq/m<sup>3</sup> [17], but its concentrations lower in the other types may be attributed to the quality of selection processes for samples where rock salt was selected from the bottom of sea and this due to increase in the radon concentration. **Figure 3** shown the annual effective dose from corresponding radon concentration with types of salt it is found that in local salt has range between 7.25 and 12.08 m Sv y�<sup>1</sup> with average 9.67 m Sv y�<sup>1</sup> and in imported salt has range between 4.83 and 7.25 m Sv year�<sup>1</sup> with average 6.04 m Sv year�<sup>1</sup> but in rock salt has range between 10.47 and 13.69 m Sv year�<sup>1</sup> with average 11.8775 m Sv year�<sup>1</sup> which higher than limited value [17], as shown in **Table 1**. These values meet that the results in range with other literature [16]. The radon exhalation rate with samples salt it is found that local salt has range between 0.0011 and 0.0019 Bq m�<sup>2</sup> h�<sup>1</sup> with average 0.0015 Bq m�<sup>2</sup> h�<sup>1</sup> and in imported salt has range between 0.0007 and 0.0011 Bq m�<sup>2</sup> h�<sup>1</sup> with average 0.0009 Bq m�<sup>2</sup> h�<sup>1</sup> but in rock salt has range between 0.0016 and 0.0021 Bq m�<sup>2</sup> h�<sup>1</sup> with average 0.0018 Bq m�<sup>2</sup> h�<sup>1</sup> as shown in **Table 1**, so the percentage of radon in rock salt higher than in other type of salt.

Sodium is an important mineral needed to maintain your electrolyte balance. Excess sodium is secreted in urine, so determine the percentage of purity (concentration of NaCl) in the samples using titrimetric Mohr method it is found that 70% in local salt, 80% of imported salt and 55% in the rock salt, this difference may be attributed to the quality of purification processes. Hence, by combing chemical and physical analysis it can be concluded that the present study that used salt are not safe for rock salt so recommended to not used this type of salt in cooking food and used it in

*The variation between the annual effective dose and type of salt.*

other purpose.

**61**

**Figure 3.**

**Table 1.**

**Salt type Sample code Rn-222 (Bq/m<sup>3</sup>**

*DOI: http://dx.doi.org/10.5772/intechopen.93123*

*Radon in Foods*

**) Exhalation rate (mBqm**�**<sup>2</sup> h**�**<sup>1</sup>**

L2 409.89 0.0014 8.86 L3 558.94 0.0019 12.08 L4 484.42 0.0016 10.47

I2 298.10 0.0010 6.44 I3 260.84 0.0008 5.64 I4 335.36 0.0011 7.25

R2 484.42 0.0016 10.47 R3 558.94 0.0018 12.08 R4 633.47 0.0021 13.69

Local L1 335.36 0.0011 7.25

Range R 335.46–558.94 0.0011–0.0019 7.25–12.08 Average Av 447.1525 0.0015 9.665 Imported I1 223.58 0.0007 4.83

Range R 223.58–335.36 0.0007–0.0011 4.83–7.25 Average Av 279.47 0.0009 6.04 Rock R1 521.68 0.0017 11.27

Range R 484.42–633.47 0.0016–0.0021 10.47–13.69 Average Av 549.6275 0.0018 11.8775

*The radon concentration, annual effective dose and radon exhalation rate for edible salt by CR-39.*

**) Effective dose (mSv/y)**

**Figure 2.** *Variation of radon concentration with different salt types.*


*Radon in Foods DOI: http://dx.doi.org/10.5772/intechopen.93123*

#### **Table 1.**

Concentrations of radionuclides in foods which are grown in the soil depend on the concentrations of theses radionuclides in dry soils. Transfer factor (TF) can be

where *Cfoods* is the activity concentration of 226Ra or 222Rn in dry weight of foods

The variation of radon concentration with types of salt is shown in **Figure 2**. It is

found that the radon concentration in local salt has range between 335.46 and

223.58 and 335.36 Bq m�<sup>3</sup> with average 279.47 Bq m�<sup>3</sup> but in rock salt has range between 484.42 and 633.47 Bq m�<sup>3</sup> with average 549.63 Bq m�<sup>3</sup> as showed in (**Table 1**), It is shown that the concentration in rock salt is higher than the

recommended value 400 Bq/m<sup>3</sup> [17], but its concentrations lower in the other types may be attributed to the quality of selection processes for samples where rock salt was selected from the bottom of sea and this due to increase in the radon concentration. **Figure 3** shown the annual effective dose from corresponding radon concentration with types of salt it is found that in local salt has range between 7.25 and 12.08 m Sv y�<sup>1</sup> with average 9.67 m Sv y�<sup>1</sup> and in imported salt has range between 4.83 and 7.25 m Sv year�<sup>1</sup> with average 6.04 m Sv year�<sup>1</sup> but in rock salt has range between 10.47 and 13.69 m Sv year�<sup>1</sup> with average 11.8775 m Sv year�<sup>1</sup> which higher than limited value [17], as shown in **Table 1**. These values meet that the results in range with other literature [16]. The radon exhalation rate with samples salt it is found that local salt has range between 0.0011 and 0.0019 Bq m�<sup>2</sup> h�<sup>1</sup> with average 0.0015 Bq m�<sup>2</sup> h�<sup>1</sup> and in imported salt has range between 0.0007 and 0.0011 Bq m�<sup>2</sup> h�<sup>1</sup> with average 0.0009 Bq m�<sup>2</sup> h�<sup>1</sup> but in rock salt has range between 0.0016 and 0.0021 Bq m�<sup>2</sup> h�<sup>1</sup> with average 0.0018 Bq m�<sup>2</sup> h�<sup>1</sup> as shown in **Table 1**, so the percentage of radon in rock salt higher than in other type of salt.

*dry weight*

*dry weight* (6)

, and in imported salt has range between

*TF* <sup>¼</sup> *Cfoods Bq kg*�<sup>1</sup>

*Csoil Bq kg*�<sup>1</sup>

samples and *Csoil* is the average activity concentration of radionuclide (226Ra or

calculated by the following equation [8, 15, 16]:

*Recent Techniques and Applications in Ionizing Radiation Research*

222Rn) in dry weight of soil samples.

**3. The concentration of radon**

558.94 Bq m�<sup>3</sup> with average 447.15 Bq m�<sup>3</sup>

**3.1 The radon in salt**

**Figure 2.**

**60**

*Variation of radon concentration with different salt types.*

*The radon concentration, annual effective dose and radon exhalation rate for edible salt by CR-39.*

**Figure 3.**

*The variation between the annual effective dose and type of salt.*

Sodium is an important mineral needed to maintain your electrolyte balance. Excess sodium is secreted in urine, so determine the percentage of purity (concentration of NaCl) in the samples using titrimetric Mohr method it is found that 70% in local salt, 80% of imported salt and 55% in the rock salt, this difference may be attributed to the quality of purification processes. Hence, by combing chemical and physical analysis it can be concluded that the present study that used salt are not safe for rock salt so recommended to not used this type of salt in cooking food and used it in other purpose.

#### **3.2 The radon in food**

The data of track density (track/cm<sup>2</sup> ), concentration of radon-222 (Bq/m<sup>3</sup> ), effective radium content (Bq/kg), exhalation rate (mBqm<sup>2</sup> h<sup>1</sup> ), and annual

effective dose (mSv/y) for eight types from household foods are presented in **Table 2**. The average activity concentrations of Rn-222 are 262.19 18.31, 333.05 8.07, 276.36 15.35, 170.07 37.52, 304.71 11.03, 517.29 34.88, 233.84 24.22, and 701.53 73.30 Bq/m3 for coffee, powder milk, tea, powder coconut, rice, cornstarch, flour, and sugar respectively. Its observed from **Figure 4**. There are a large variations in the values of radon concentrations along all the samples, while the maximum values of Rn-222 concentration are observed at sugar, and cornstarch are 701.53 73.30, and 517.29 34.88 Bq/m<sup>3</sup> respectively, and the

lowest value was observed at powder coconut is 170.07 37.52 Bq/m<sup>3</sup>

role of radon and thoron in causing the same [21].

*Radon in Foods*

*DOI: http://dx.doi.org/10.5772/intechopen.93123*

*Radon-222 concentrations for different types for household foods.*

**Figure 4.**

**63**

tion may be due to the differences in the nature of these samples and also its bases content [2]. The gained values of radon concentrations for coffee, powder milk, tea, powder coconut, rice, and flour were found to be lower than the recommended value 400 Bq/m<sup>3</sup> [18], but its concentrations for cornstarch, and sugar were relatively higher than the recommended value. The high values of radon concentrations in foods are due to the presence of any type of ionizing radiation found in the air, soil or water which are transferred to the food and are grown on it [19]. The source of radon in foods is mainly from the activity concentration of its parent Ra-226. When radionuclide such as radium intake from the soil and irrigation water through the root and as a result of that it is transferred to foods [20]. When human are ingested radon daughters undergoes radioactive decay are transported to lung and causes changes to DNA structures. Also, several studies on lung cancer indicate the

**Table 2** displays the average values of effective radium content are 6.12 0.43, 7.77 0.19, 6.45 0.37, 3.97 0.88, 7.11 0.26, 12.07 0.81, 5.46 0.57, and 16.37 1.70 Bqkg<sup>1</sup> for coffee, powder milk, tea, powder coconut, rice, cornstarch, flour, and sugar respectively. All values of effective radium content for all types of household foods were found to be lower than the permission level of 370 Bq kg<sup>1</sup>

[22]. The average values of exhalation rate of radon are 365.61 25.52,

464.42 11.25, 385.37 21.40, 237.15 52.31, 424.90 15.38, 721.33 48.65, 326.08 33.76, and 978.25 102.22 mBqm<sup>2</sup> <sup>h</sup><sup>1</sup> for coffee, powder milk, tea, powder coconut, rice, cornstarch, flour, and sugar respectively as shown at **Table 1**. A positive strong correlation was observed between effective radium content with both radon concentration, and exaltation rate with linear coefficients (R2 = 1) as revealed at **Figure 5a** and **b**. The correlations coefficients are positively linear, these

. This varia-


#### **Table 2.**

*Track density (track/cm<sup>2</sup> ), Radon-222 concentration (Bq/m3 ), effective radium content (Bq/kg), exhalation rate (mBqm<sup>2</sup> h<sup>1</sup> ), and annual effective dose (mSv/y) for household foods.*

#### *Radon in Foods DOI: http://dx.doi.org/10.5772/intechopen.93123*

**3.2 The radon in food**

**Foods type**

Powder milk

Powder coconut

**Table 2.**

**62**

*Track density (track/cm<sup>2</sup>*

*rate (mBqm<sup>2</sup> h<sup>1</sup>*

The data of track density (track/cm<sup>2</sup>

**Track density (track/cm<sup>2</sup>**

**Sample code**

effective radium content (Bq/kg), exhalation rate (mBqm<sup>2</sup> h<sup>1</sup>

*Recent Techniques and Applications in Ionizing Radiation Research*

**Rn-222 (Bq/m<sup>3</sup> )**

Coffee C1 28571.43 297.62 10.92 6.94 0.26 415.01 15.22 7.51 0.28

Average Av 25170.07 262.19 18.31 6.12 0.43 365.61 25.52 6.61 0.46

Average Av 31972.79 333.05 8.07 7.77 0.19 464.42 11.25 8.40 0.20 Tea T1 28571.43 297.62 10.92 6.94 0.26 415.01 15.22 7.51 0.28

Average Av 26530.61 276.36 15.35 6.45 0.37 385.37 21.40 6.97 0.39

Average Av 16326.53 170.07 37.52 3.97 0.88 237.15 52.31 4.29 0.95 Rice R1 20408.16 212.59 28.65 4.96 0.68 296.44 39.94 5.36 0.72

Average Av 29251.70 304.71 11.03 7.11 0.26 424.90 15.38 7.69 0.28 Cornstarch S1 55102.04 573.98 46.70 13.39 1.08 800.38 65.14 14.48 1.18

Average Av 49659.86 517.29 34.88 12.07 0.81 721.33 48.65 13.05 0.88 Flour F1 26530.61 276.36 15.36 6.45 0.36 385.37 21.40 6.97 0.39

Average Av 22448.98 233.84 24.22 5.46 0.57 326.08 33.76 5.90 0.61 Sugar U1 61224.49 637.76 60.00 14.88 1.39 889.32 83.68 16.09 1.51

Average Av 67346.94 701.53 73.30 16.37 1.70 978.25 102.22 17.70 1.85

*), Radon-222 concentration (Bq/m3*

*), and annual effective dose (mSv/y) for household foods.*

**)**

), concentration of radon-222 (Bq/m<sup>3</sup>

**Exhalation rate (mBqm<sup>2</sup> h<sup>1</sup>**

**Effective radium content (Bq/kg)**

C2 24489.80 255.10 19.79 5.95 0.47 355.73 27.58 6.44 0.50 C3 22448.98 233.84 24.22 5.46 0.57 326.08 33.76 5.90 0.61

P1 36734.69 382.65 6.81 8.93 0.15 533.59 9.51 9.65 0.17 P2 30612.24 318.88 6.49 7.44 0.16 444.66 9.04 8.04 0.16 P3 28571.43 297.62 10.92 6.94 0.26 415.01 15.22 7.51 0.28

T2 30612.24 318.88 6.49 7.44 0.16 444.66 9.04 8.04 0.16 T3 20408.16 212.59 28.65 4.96 0.68 296.44 39.94 5.36 0.72

O1 16326.53 170.07 37.52 3.97 0.88 237.15 52.31 4.29 0.95 O2 18367.35 191.33 33.08 4.46 0.78 266.79 46.13 4.83 0.83 O3 14285.71 148.81 41.95 3.47 0.99 207.51 58.49 3.75 1.06

R2 34693.88 361.39 2.37 8.43 0.05 503.95 3.33 9.12 0.06 R3 32653.06 340.14 2.06 7.94 0.05 474.30 2.86 8.58 0.05

S2 44897.96 467.69 24.54 10.91 0.57 652.17 34.23 11.80 0.62 S3 48979.59 510.20 33.40 11.90 0.77 711.45 46.59 12.87 0.84

F2 18367.35 191.33 33.08 4.46 0.78 266.79 46.13 4.83 0.83 F3 22448.98 233.84 24.22 5.46 0.57 326.08 33.76 5.90 0.61

U2 73469.39 765.31 86.60 17.86 2.01 1067.18 120.77 19.31 2.19 U3 67346.94 701.53 73.30 16.37 1.70 978.25 102.22 17.70 1.85

*), effective radium content (Bq/kg), exhalation*

),

**Effective dose (mSv/y)**

), and annual

**)**

effective dose (mSv/y) for eight types from household foods are presented in **Table 2**. The average activity concentrations of Rn-222 are 262.19 18.31, 333.05 8.07, 276.36 15.35, 170.07 37.52, 304.71 11.03, 517.29 34.88, 233.84 24.22, and 701.53 73.30 Bq/m3 for coffee, powder milk, tea, powder coconut, rice, cornstarch, flour, and sugar respectively. Its observed from **Figure 4**. There are a large variations in the values of radon concentrations along all the samples, while the maximum values of Rn-222 concentration are observed at sugar, and cornstarch are 701.53 73.30, and 517.29 34.88 Bq/m<sup>3</sup> respectively, and the lowest value was observed at powder coconut is 170.07 37.52 Bq/m<sup>3</sup> . This variation may be due to the differences in the nature of these samples and also its bases content [2]. The gained values of radon concentrations for coffee, powder milk, tea, powder coconut, rice, and flour were found to be lower than the recommended value 400 Bq/m<sup>3</sup> [18], but its concentrations for cornstarch, and sugar were relatively higher than the recommended value. The high values of radon concentrations in foods are due to the presence of any type of ionizing radiation found in the air, soil or water which are transferred to the food and are grown on it [19]. The source of radon in foods is mainly from the activity concentration of its parent Ra-226. When radionuclide such as radium intake from the soil and irrigation water through the root and as a result of that it is transferred to foods [20]. When human are ingested radon daughters undergoes radioactive decay are transported to lung and causes changes to DNA structures. Also, several studies on lung cancer indicate the role of radon and thoron in causing the same [21].

**Table 2** displays the average values of effective radium content are 6.12 0.43, 7.77 0.19, 6.45 0.37, 3.97 0.88, 7.11 0.26, 12.07 0.81, 5.46 0.57, and 16.37 1.70 Bqkg<sup>1</sup> for coffee, powder milk, tea, powder coconut, rice, cornstarch, flour, and sugar respectively. All values of effective radium content for all types of household foods were found to be lower than the permission level of 370 Bq kg<sup>1</sup> [22]. The average values of exhalation rate of radon are 365.61 25.52, 464.42 11.25, 385.37 21.40, 237.15 52.31, 424.90 15.38, 721.33 48.65, 326.08 33.76, and 978.25 102.22 mBqm<sup>2</sup> <sup>h</sup><sup>1</sup> for coffee, powder milk, tea, powder coconut, rice, cornstarch, flour, and sugar respectively as shown at **Table 1**. A positive strong correlation was observed between effective radium content with both radon concentration, and exaltation rate with linear coefficients (R2 = 1) as revealed at **Figure 5a** and **b**. The correlations coefficients are positively linear, these

**Figure 4.** *Radon-222 concentrations for different types for household foods.*

The values of transfer factor (TF) for radionuclides Rn-222, and Ra-226 in different types of household foods were presented at **Table 3**. The values of TF of Rn-222 varied from 0.60 0.17 to 3.06 0.35 with an average of 1.40 0.11, while the values of TF of Ra-226 varied from 0.11 0.029 to 0.54 0.060 with an average of 0.25 0.02. All values of TF for both radionuclides Rn-222, and Ra-226 are high, this may be due to organic substance content or small pH number of soil, so the radionuclides are absorbed at high levels through plants or seeds due to

**Foods type Sample code TF for Rn-222 TF For Ra-226** Coffee C1 1.19 0.04 0.21 0.008

Average Av 1.05 0.07 0.19 0.013 Powder milk P1 1.53 0.03 0.27 0.004

Average Av 1.33 0.03 0.24 0.006 Tea T1 1.19 0.04 0.21 0.008

Average Av 1.11 0.06 0.20 0.011 Powder coconut O1 0.68 0.15 0.12 0.027

Average Av 0.68 0.15 0.12 0.026 Rice R1 0.85 0.11 0.15 0.021

Average Av 1.22 0.04 0.22 0.008

C2 1.02 0.08 0.18 0.015 C3 0.94 0.10 0.17 0.017

P2 1.28 0.03 0.23 0.004 P3 1.19 0.04 0.21 0.008

T2 1.28 0.03 0.23 0.004 T3 0.85 0.11 0.15 0.021

O2 0.77 0.13 0.14 0.023 O3 0.60 0.17 0.11 0.029

R2 1.45 0.01 0.26 0.002 R3 1.36 0.01 0.24 0.002

*Average values of annual effective dose for different types of household foods.*

**Figure 6.**

*Radon in Foods*

*DOI: http://dx.doi.org/10.5772/intechopen.93123*

**65**

**Figure 5.** *Relations between effective radium content with (a) Rn-222 (Bq/m3 ), (b) exhalation rate (mBqm<sup>2</sup> h<sup>1</sup> ).*

may be due to the values of radon concentrations and exhalation rate are mainly dependent on the values of effective radium, and the radon exhalation analysis is significant for knowing the relative impact of the material to the total radon concentration found in food samples and useful to study radon health hazard [23, 24].

We can see from **Figure 6** the high value of effective dose was observed in sugar, and the lower value of effective dose was observed at powder coconut, and there are a large variations in the values of effective dose for all the types of samples as 6.61 0.46, 8.40 0.20, 6.97 0.39, 4.29 0.95, 7.69 0.28, 13.05 0.88, 5.90 0.61, and 17.70 1.85 mSv/y for coffee, powder milk, tea, powder coconut, rice, cornstarch, flour, and sugar respectively. All values of effective dose within the recommended limit (3–10 mSv/y) [25], except its values for cornstarch and sugar are relatively high.

**Figure 6.** *Average values of annual effective dose for different types of household foods.*

The values of transfer factor (TF) for radionuclides Rn-222, and Ra-226 in different types of household foods were presented at **Table 3**. The values of TF of Rn-222 varied from 0.60 0.17 to 3.06 0.35 with an average of 1.40 0.11, while the values of TF of Ra-226 varied from 0.11 0.029 to 0.54 0.060 with an average of 0.25 0.02. All values of TF for both radionuclides Rn-222, and Ra-226 are high, this may be due to organic substance content or small pH number of soil, so the radionuclides are absorbed at high levels through plants or seeds due to


may be due to the values of radon concentrations and exhalation rate are mainly dependent on the values of effective radium, and the radon exhalation analysis is significant for knowing the relative impact of the material to the total radon concentration found in food samples and useful to study radon health hazard [23, 24]. We can see from **Figure 6** the high value of effective dose was observed in sugar, and the lower value of effective dose was observed at powder coconut, and there are a large variations in the values of effective dose for all the types of samples as 6.61 0.46, 8.40 0.20, 6.97 0.39, 4.29 0.95, 7.69 0.28, 13.05 0.88, 5.90 0.61, and 17.70 1.85 mSv/y for coffee, powder milk, tea, powder coconut, rice, cornstarch, flour, and sugar respectively. All values of effective dose within the recommended limit (3–10 mSv/y) [25], except its values for cornstarch and sugar

*), (b) exhalation rate (mBqm<sup>2</sup> h<sup>1</sup>*

*).*

*Relations between effective radium content with (a) Rn-222 (Bq/m3*

*Recent Techniques and Applications in Ionizing Radiation Research*

are relatively high.

**64**

**Figure 5.**

#### *Recent Techniques and Applications in Ionizing Radiation Research*


(coffee, tea, powder milk, rice, flour, cornstarch, and powder coconut) and different types of salt have been analyzed for radon, and radium concentrations using closed-can technique based on Nuclear Track Detectors (SSNTD) CR-39. The range of radon �222 concentrations at different types of household foods are 170.07 (at

than the recommend value of ICRP for cornstarch and sugar. All values of effective radium content for all food samples are lower than the recommended value. Exhalation rate of radon is relatively high at all samples. The average values of annual effective dose in mSv/y are within the recommended limit of ICRP values except its values for cornstarch and sugar are relatively high, and there are a wide range of variations in the values of transfer factor for Rn-222, and Ra-226 for all types. Then all types of foods which are analysis in this study are safe for using except the kinds

, and the values of Radon-222 are higher

powder coconut) �701.53 (at sugar) Bq/m<sup>3</sup>

*DOI: http://dx.doi.org/10.5772/intechopen.93123*

of sugar and cornstarch.

*Radon in Foods*

**Author details**

Saudi Arabia

**67**

Shams University, Cairo, Egypt

dhshabaan@jazanu.edu.sa

provided the original work is properly cited.

Tayseer I. Al-Naggar1,2,4 and Doaa H. Shabaan1,3\*

1 Department of Physics, College of Women for Art, Science and Education, Ain

2 Department of Physics, Faculty of Arts and Sciences, Najran University, Najran,

3 Physics Department, University Collage of Samtah, Jazan University, Jazan, KSA

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

4 Unit of Radiation Protection, Najran University, Najran, Saudi Arabia

\*Address all correspondence to: doaa.hassantaha@women.asu.edu.eg;

#### **Table 3.**

*Transfer factor of Radon-222, and Ra-226 for different types of household foods.*

**Figure 7.** *Transfer factor of Ra-222, and Ra-226 for different types of household foods.*

increase in the value of organic matter in the soil. Therefore, the uptake of radium in plant increases by increasing the concentration of organic acids and organic acids especially citric acid play an effective role on the uptake of Ra-226 by the plants due to pH reduction and complex formation of organic acids with elements in the soil. [15, 16, 26]. **Figure 7** shows there are a wide range of variations in the values of transfer factor of Rn-222, and Ra-226 along all the samples.

#### **4. Conclusion**

This chapter deals with the assessment of radioactive isotopes (Rn-22, and Ra-226) in various natural environmental samples. Some types of household foods

#### *Radon in Foods DOI: http://dx.doi.org/10.5772/intechopen.93123*

(coffee, tea, powder milk, rice, flour, cornstarch, and powder coconut) and different types of salt have been analyzed for radon, and radium concentrations using closed-can technique based on Nuclear Track Detectors (SSNTD) CR-39. The range of radon �222 concentrations at different types of household foods are 170.07 (at powder coconut) �701.53 (at sugar) Bq/m<sup>3</sup> , and the values of Radon-222 are higher than the recommend value of ICRP for cornstarch and sugar. All values of effective radium content for all food samples are lower than the recommended value. Exhalation rate of radon is relatively high at all samples. The average values of annual effective dose in mSv/y are within the recommended limit of ICRP values except its values for cornstarch and sugar are relatively high, and there are a wide range of variations in the values of transfer factor for Rn-222, and Ra-226 for all types. Then all types of foods which are analysis in this study are safe for using except the kinds of sugar and cornstarch.

### **Author details**

Tayseer I. Al-Naggar1,2,4 and Doaa H. Shabaan1,3\*

1 Department of Physics, College of Women for Art, Science and Education, Ain Shams University, Cairo, Egypt

2 Department of Physics, Faculty of Arts and Sciences, Najran University, Najran, Saudi Arabia

3 Physics Department, University Collage of Samtah, Jazan University, Jazan, KSA

4 Unit of Radiation Protection, Najran University, Najran, Saudi Arabia

\*Address all correspondence to: doaa.hassantaha@women.asu.edu.eg; dhshabaan@jazanu.edu.sa

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

increase in the value of organic matter in the soil. Therefore, the uptake of radium in plant increases by increasing the concentration of organic acids and organic acids especially citric acid play an effective role on the uptake of Ra-226 by the plants due to pH reduction and complex formation of organic acids with elements in the soil. [15, 16, 26]. **Figure 7** shows there are a wide range of variations in the values of

**Foods type Sample code TF for Rn-222 TF For Ra-226** Cornstarch S1 2.30 0.19 0.41 0.033

Average Av 2.07 0.14 0.37 0.024 Flour F1 1.11 0.06 0.20 0.010

Average Av 0.94 0.10 0.17 0.017 Sugar U1 2.55 0.24 0.45 0.042

Average Av 2.81 0.29 0.50 0.051

*Transfer factor of Radon-222, and Ra-226 for different types of household foods.*

*Recent Techniques and Applications in Ionizing Radiation Research*

S2 1.87 0.10 0.33 0.017 S3 2.04 0.13 0.36 0.023

F2 0.77 0.13 0.14 0.023 F3 0.94 0.10 0.17 0.017

U2 3.06 0.35 0.54 0.060 U3 2.81 0.29 0.50 0.052

This chapter deals with the assessment of radioactive isotopes (Rn-22, and Ra-226) in various natural environmental samples. Some types of household foods

transfer factor of Rn-222, and Ra-226 along all the samples.

*Transfer factor of Ra-222, and Ra-226 for different types of household foods.*

**4. Conclusion**

**66**

**Figure 7.**

**Table 3.**

### **References**

[1] Khan MS, Srivastava DS, Ameer A. Study of radium content and radon exhalation rates in soil samples of northern India. Environment and Earth Science. 2012. DOI: 10.1007/s12665-012- 1581-7

[2] Sasmaz A, Yaman M. Determination of uranium and thorium in soil and plant parts around abandoned lead– zink–copper mining area. Communication in Soil Science and Plant Analysis. 2008;**39**:2568-2583

[3] Burkart W, Danesi PR, Bleise A. Properties use and health effects of depleted uranium. Journal of Environmental Radioactivity. 2002;**64**: 93-112

[4] Abdalsattar KH, Laith AN. Radium and uranium concentrations measurements in vegetables samples of Iraq. Detection. 2015;**3**:21-28

[5] Shoeib MY, Thabayneh KM. Assessment of natural radiation exposure and radon exhalation rate in various samples of Egyptian building materials. Journal of Radiation Research and Applied Science. 2014;**7**:174-181

[6] AL-Naggar TI, Shabaan DH. Simple analysis of radioactivity, and assessment of radiological hazards in different types of household foods. International Journal of Recent Scientific Research. 2018;**9**(3):24838-24843. DOI: 10.24327/ ijrsr.2018.0903.1736

[7] Ammar AB, Asmaa AA, Huda SA. Radon concentration measurement in an imported tea using nuclear track detector CN-85. Tikrit Journal of Pure Science. 2016;**21**(1):68-70

[8] IAEA. Handbook of Parameter Values for the Prediction of Radionuclide Transfer in Terrestrial and Freshwater Environments. International Atomic Energy Agency; Technical

Reports Series No. 472. 2010. p. 79. Available from: https://www.iaea.org/ publications/8201/handbook-ofparameter-values-for-the-prediction-ofradionuclide-transfer-in-terrestrial-andfreshwater-environments

[16] Mohammad AS, Thamer A, Muzahir AB, Omar ARA. Transfer factors for natural radioactivity into date palm pits. Journal of

[17] International Atomic Energy

of radium technical reports.

75-79

*Radon in Foods*

pdf

Environmental Radioactivity. 2017;**167**:

*DOI: http://dx.doi.org/10.5772/intechopen.93123*

Research and Applied Sciences. 2016;**9**:

[24] Kazuki I, Masahiro H, Kazuaki Y, Shinji T. Measurements of radon exhalation rate in NORM used as consumer products in Japan. Applied Radiation and Isotopes. 2017;**126**:

[25] ICRP. Protection Against Rn-222 at Home and at Work. International Commission on Radiological Protection Publication 65. Annals of ICRP 23 (2).

Oxford: Pergamon Press; 1993

[26] Harb S, El-Kamel AH, Abd El-Mageed AI, Abbady A, Rashed W. Radioactivity levels and soil-to-plant transfer factor of natural radionuclides from protectorate area in Aswan, Egypt. World Journal of Nuclear Science and Technology. 2014;**4**:7-15

41-46

304-306

Agency (IAEA). Environment behaviors

International Atomic Energy Agency (IAEA). 1990;**1**(310):192. Available from: https://www-pub.iaea.org/ MTCD/Publications/PDF/trs476\_web.

[18] International Commission on Radiological Protection (ICRP). Radionuclides Release into the Environment. Oxford, New York:

[19] Maria AM, Donatella D, Carla R, Laura F, Claudio B. Radioactivity in honey of the Central Italy. Food Chemistry. 2016;**202**:349-355

[20] Nasrin F, Ali AS, Kazem N, Mohammad RK et al. Radioactivity levels in the mostly local foodstuff consumed by residents of the high-level natural radiation areas of Ramsar, Iran. Journal of Environmental Radioactivity.

[21] Ramsiya M, Antony J, Jojo PJ. Estimation of indoor radon and thoron in dwellings of Palakkad, Kerala, India using solid state nuclear track detectors. Journal of Radiation Research and Applied Sciences. 2017;**10**:269-272

[22] Organization for Economic

**69**

Cooperation and Development (OECD). Exposure to Radiation from Natural Radioactivity in Building Materials. Report by a Group of Experts of the OECD. Nuclear Energy Agency; 2009

[23] Hesham AY, Gehad MS, El-Farrash AH, Hamza A. Radon exhalation rate for phosphate rocks samples using alpha track detectors. Journal of Radiation

2017. 169–170. 209–213

Pergamum Press; 1987

[9] Hassan HM, Shabaan DH. Physicochemical and radon analysis of drinking water available in Samtah-Jazan city southwest of Saudia Arabia. Journal of Desalination and Water Treatment. 2015;**57**:19140-19148

[10] Ayman MA, Ali A. Radon irradiation chamber and its applications. Nuclear Instruments and Methods in Physical Research A. 2015;**786**:78-82

[11] Hayam NH, Ali AA, Zahrah BM. Study of radon levels in fruits samples using LR-115 type II detector. Journal of Environmental Science & Technology. 2016;**9**(6):446-451

[12] Ridha AA, Hasan HA. Lung cancer risks due to the radon in cigarette tobacco. Radiochemistry. 2016;**59, 2**: 208-214

[13] Abdalsattar KH, Laith AN, Abbas FH, Fadhil KF. Lung cancer risk due to radon in different brand cigarette tobacco in Iraqi market. WSN. 2017; **77**(2):163-176. EISSN 2392–2192

[14] UNSCEAR (United Nations Scientific Committee on The Effects of Atomic Radiation to The General Assembly). Appendix I: Epidemiological evaluation of radiation induced cancer. Appendix G: Biological effects of low radiation doses. 2000

[15] Oufni L, Manaut N, Taj S, Manaut B. Determination of radon and thoron concentrations in different parts of some plants used in traditional medicine using nuclear track detectors. American Journal of Environmental Protection. 2013;**1**(2):34-40

#### *Radon in Foods DOI: http://dx.doi.org/10.5772/intechopen.93123*

[16] Mohammad AS, Thamer A, Muzahir AB, Omar ARA. Transfer factors for natural radioactivity into date palm pits. Journal of Environmental Radioactivity. 2017;**167**: 75-79

**References**

1581-7

93-112

[1] Khan MS, Srivastava DS, Ameer A. Study of radium content and radon exhalation rates in soil samples of northern India. Environment and Earth Science. 2012. DOI: 10.1007/s12665-012-

*Recent Techniques and Applications in Ionizing Radiation Research*

Reports Series No. 472. 2010. p. 79. Available from: https://www.iaea.org/ publications/8201/handbook-of-

freshwater-environments

2015;**57**:19140-19148

2016;**9**(6):446-451

208-214

[10] Ayman MA, Ali A. Radon

parameter-values-for-the-prediction-ofradionuclide-transfer-in-terrestrial-and-

[9] Hassan HM, Shabaan DH. Physicochemical and radon analysis of drinking water available in Samtah-Jazan city southwest of Saudia Arabia. Journal of Desalination and Water Treatment.

irradiation chamber and its applications. Nuclear Instruments and Methods in Physical Research A. 2015;**786**:78-82

[11] Hayam NH, Ali AA, Zahrah BM. Study of radon levels in fruits samples using LR-115 type II detector. Journal of Environmental Science & Technology.

[12] Ridha AA, Hasan HA. Lung cancer risks due to the radon in cigarette tobacco. Radiochemistry. 2016;**59, 2**:

Abbas FH, Fadhil KF. Lung cancer risk due to radon in different brand cigarette tobacco in Iraqi market. WSN. 2017; **77**(2):163-176. EISSN 2392–2192

[15] Oufni L, Manaut N, Taj S, Manaut B. Determination of radon and thoron concentrations in different parts of some plants used in traditional medicine using nuclear track detectors. American Journal of Environmental Protection.

[13] Abdalsattar KH, Laith AN,

[14] UNSCEAR (United Nations Scientific Committee on The Effects of Atomic Radiation to The General Assembly). Appendix I: Epidemiological evaluation of radiation induced cancer. Appendix G: Biological effects of low

radiation doses. 2000

2013;**1**(2):34-40

[2] Sasmaz A, Yaman M. Determination of uranium and thorium in soil and plant parts around abandoned lead–

Communication in Soil Science and Plant Analysis. 2008;**39**:2568-2583

[3] Burkart W, Danesi PR, Bleise A. Properties use and health effects of depleted uranium. Journal of

Environmental Radioactivity. 2002;**64**:

[4] Abdalsattar KH, Laith AN. Radium

measurements in vegetables samples of

[6] AL-Naggar TI, Shabaan DH. Simple analysis of radioactivity, and assessment of radiological hazards in different types of household foods. International Journal of Recent Scientific Research. 2018;**9**(3):24838-24843. DOI: 10.24327/

[7] Ammar AB, Asmaa AA, Huda SA. Radon concentration measurement in an imported tea using nuclear track detector CN-85. Tikrit Journal of Pure

[8] IAEA. Handbook of Parameter Values for the Prediction of

Radionuclide Transfer in Terrestrial and Freshwater Environments. International Atomic Energy Agency; Technical

and uranium concentrations

Iraq. Detection. 2015;**3**:21-28

ijrsr.2018.0903.1736

Science. 2016;**21**(1):68-70

**68**

[5] Shoeib MY, Thabayneh KM. Assessment of natural radiation exposure and radon exhalation rate in various samples of Egyptian building materials. Journal of Radiation Research and Applied Science. 2014;**7**:174-181

zink–copper mining area.

[17] International Atomic Energy Agency (IAEA). Environment behaviors of radium technical reports. International Atomic Energy Agency (IAEA). 1990;**1**(310):192. Available from: https://www-pub.iaea.org/ MTCD/Publications/PDF/trs476\_web. pdf

[18] International Commission on Radiological Protection (ICRP). Radionuclides Release into the Environment. Oxford, New York: Pergamum Press; 1987

[19] Maria AM, Donatella D, Carla R, Laura F, Claudio B. Radioactivity in honey of the Central Italy. Food Chemistry. 2016;**202**:349-355

[20] Nasrin F, Ali AS, Kazem N, Mohammad RK et al. Radioactivity levels in the mostly local foodstuff consumed by residents of the high-level natural radiation areas of Ramsar, Iran. Journal of Environmental Radioactivity. 2017. 169–170. 209–213

[21] Ramsiya M, Antony J, Jojo PJ. Estimation of indoor radon and thoron in dwellings of Palakkad, Kerala, India using solid state nuclear track detectors. Journal of Radiation Research and Applied Sciences. 2017;**10**:269-272

[22] Organization for Economic Cooperation and Development (OECD). Exposure to Radiation from Natural Radioactivity in Building Materials. Report by a Group of Experts of the OECD. Nuclear Energy Agency; 2009

[23] Hesham AY, Gehad MS, El-Farrash AH, Hamza A. Radon exhalation rate for phosphate rocks samples using alpha track detectors. Journal of Radiation

Research and Applied Sciences. 2016;**9**: 41-46

[24] Kazuki I, Masahiro H, Kazuaki Y, Shinji T. Measurements of radon exhalation rate in NORM used as consumer products in Japan. Applied Radiation and Isotopes. 2017;**126**: 304-306

[25] ICRP. Protection Against Rn-222 at Home and at Work. International Commission on Radiological Protection Publication 65. Annals of ICRP 23 (2). Oxford: Pergamon Press; 1993

[26] Harb S, El-Kamel AH, Abd El-Mageed AI, Abbady A, Rashed W. Radioactivity levels and soil-to-plant transfer factor of natural radionuclides from protectorate area in Aswan, Egypt. World Journal of Nuclear Science and Technology. 2014;**4**:7-15

**Chapter 6**

**Abstract**

**1. Introduction**

**71**

Mathematical Expressions

The measurement of radon, thoron and their progeny concentrations also leads to the knowledge of the presence of radioactive elements, which are the sources of these elements such as Uranium-238 and Thorium-232. Using of Solid State Nuclear Tracks Detectors (SSNTDs) it is probably the most widely applied for long term radon measurements. In this chapter, we derived the most important mathematical relationships that researchers need in radon measurements to calculate such as average radon concentration, exhalation rate, equilibrium factor, radon diffusion coefficient and transmission factor to get actual radon concentration in air atmosphere. The relationship between theoretical and experiment calibration drive and

**Keywords:** technique radon measurements, SSNTDs, mathematical expressions

The measurement of radon, thoron and their progeny concentrations also leads to the knowledge of the presence of radioactive elements, which are the sources of these elements. Since Uranium-238 is the parent nuclei of Radon and Thorium-232 that of Thoron, hence with the concentrations of these gases in air, one can predict the presence of high or low concentrations of the source. Radon (chemical symbol, Rn) is a naturally occurring radioactive gaseous element. 222Rn is the decay product of 226Ra, which are part of the long decay chain of 238U. Since uranium is found everywhere in the earth's crust, 226Ra and 222Rn are present in almost all rocks, soil, and water. 222Rn is the decay to short -lived radioactive elements 218Po, 214Pb, 214Bi and 214Po, respectively, which called radon daughters. These daughter products, being the isotopes of heavy metals, get attached to the existing aerosols, suspended particulate matters, in the atmosphere, therefore the inhalations of radon 222Rn progeny are the most important source of irradiation of the human respiratory. The measurement of radon, thoron and their progeny concentrations was done in many countries, with the improvement of experimental apparatus and technical formulation, the same is going on till today. Among the different techniques available for radon measurements, is the method which is based on the use of Solid State Nuclear Tracks Detectors (SSNTDs) it is probably the most widely applied for long term radon measurements. Nuclear track detectors are a plastic detector uses to register alpha particles in the form of tracks. That is will become visible under the optical microscope upon suitable chemical etching of the SSNTDs', the most commonly used CR-39. The closed-can technique (sealed cylindrical plastic container**)** employs

of Radon Measurements

other mathematical relationships are given in this chapter.

*Ali Farhan Nader Alrekabi*

#### **Chapter 6**

## Mathematical Expressions of Radon Measurements

*Ali Farhan Nader Alrekabi*

#### **Abstract**

The measurement of radon, thoron and their progeny concentrations also leads to the knowledge of the presence of radioactive elements, which are the sources of these elements such as Uranium-238 and Thorium-232. Using of Solid State Nuclear Tracks Detectors (SSNTDs) it is probably the most widely applied for long term radon measurements. In this chapter, we derived the most important mathematical relationships that researchers need in radon measurements to calculate such as average radon concentration, exhalation rate, equilibrium factor, radon diffusion coefficient and transmission factor to get actual radon concentration in air atmosphere. The relationship between theoretical and experiment calibration drive and other mathematical relationships are given in this chapter.

**Keywords:** technique radon measurements, SSNTDs, mathematical expressions

#### **1. Introduction**

The measurement of radon, thoron and their progeny concentrations also leads to the knowledge of the presence of radioactive elements, which are the sources of these elements. Since Uranium-238 is the parent nuclei of Radon and Thorium-232 that of Thoron, hence with the concentrations of these gases in air, one can predict the presence of high or low concentrations of the source. Radon (chemical symbol, Rn) is a naturally occurring radioactive gaseous element. 222Rn is the decay product of 226Ra, which are part of the long decay chain of 238U. Since uranium is found everywhere in the earth's crust, 226Ra and 222Rn are present in almost all rocks, soil, and water. 222Rn is the decay to short -lived radioactive elements 218Po, 214Pb, 214Bi and 214Po, respectively, which called radon daughters. These daughter products, being the isotopes of heavy metals, get attached to the existing aerosols, suspended particulate matters, in the atmosphere, therefore the inhalations of radon 222Rn progeny are the most important source of irradiation of the human respiratory. The measurement of radon, thoron and their progeny concentrations was done in many countries, with the improvement of experimental apparatus and technical formulation, the same is going on till today. Among the different techniques available for radon measurements, is the method which is based on the use of Solid State Nuclear Tracks Detectors (SSNTDs) it is probably the most widely applied for long term radon measurements. Nuclear track detectors are a plastic detector uses to register alpha particles in the form of tracks. That is will become visible under the optical microscope upon suitable chemical etching of the SSNTDs', the most commonly used CR-39. The closed-can technique (sealed cylindrical plastic container**)** employs nuclear tracks detectors to measure the radon concentration, radon exhalation rate, radium content and diffusion coefficient in the soil, building materials and water in laboratory. There are several names for this method, for example, diffusion chamber, accumulation chamber, radon exposure chamber, and time-integrated passive radon dosimeter and emanation container. Different types of cans are being used by different authors, this types is based on geometry ship (conical, cylindrical, hemispherical, and rectangular), dimensions (radius, height), and material. The can technique has some advantage, simple and efficient method, relatively inexpensive. The technique provides quite reliable measurements. One commonly used design is plastic Poly Vinyl Chloride (PVC) cylindrical can with different dimensions. The aim of this chapter will be to derive mathematical expressions, analysis and discussion, for the most of relationships of measuring the concentration of radon and placed in the summary tables [1–3].

In this chapter, we will drive and discuss the theoretical formalism which used in the research work and a complete methodology. This chapter will include the detail description of drive the most important mathematical relationships used in technique radon measurements. The present work will help in understanding the status of indoor and outdoor radon, thoron and their progeny concentrations and status of the exhalation of these gases from soil. Classification of measurements is also included in this chapter. The necessary procedures and formulae involved in measuring the concentrations of radon, thoron and their progeny, the radioactivity content of samples along with the calculations of, exhalation rate, equilibrium factor, radon diffusion coefficient and other mathematical relationships are given in this chapter.

Therefore, decay of radium and production of radon can be described by the rate

*dt* ¼ �*λRaNRa* (1)

<sup>1</sup>*=*<sup>2</sup> ¼

*dt* <sup>¼</sup> *<sup>λ</sup>RaNRa* � *<sup>λ</sup>RnNRn* (2)

*e*�*λRnt <sup>λ</sup>Ra* � *<sup>λ</sup>Rn* (3)

*A t*ðÞ¼ *λ N t*ð Þ (5)

�*λRnt* (4)

�*λRnt* (6)

�*λRnt* (7)

equations for serial radioactive decay chain (Batman equations) [5]:

*dNRn*

*NRn*ðÞ¼ *t NRa*ð Þ 0 *λRa*

*λRa λRn* � *λRa*

*λRn λRn* � *λRa*

*ΑRn*ðÞ¼ *t ΑRa*ð Þ 0 1 � *e*

Α*Ra*ð Þ 0 is original activity of radium which is constant value.

*NRn*ðÞ¼ *t*

*ΑRn*ðÞ¼ *t*

1600 *years*, Τ*Rn*

**Figure 1.**

*Closed-can technique.*

or

defined mathematically:

Eq. (5) becomes:

≫ *TRn* 1 2

Since *TRa* 1 2

becomes:

**73**

atoms without decay at any time is:

*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

*dNRa*

where λRa, λRn is decay constant for radium and radon respectively. Τ*Ra*

<sup>1</sup>*=*<sup>2</sup> ¼ 3*:*824 *d*ays are the half-life for radium and radon respectively. From Eqs. (1) and (2), we can determine the number of undecided radon atoms at a time t. By solving two equations, we will obtain the remaining number of radon

> *e*�*λRat λRn* � *λRa*

*NRa*ð Þ 0 *e*

*ΑRa*ð Þ 0 *e*

*NRa*ð Þ 0 , is the original number of radium atoms. The activity *A(t)* at time t is

þ

�*λRat* � *<sup>e</sup>*

�*λRat* � *<sup>e</sup>*

! *<sup>λ</sup>Ra* <sup>≪</sup> *<sup>λ</sup>Ra* ! *<sup>e</sup>*�*λRat* <sup>≈</sup>1&*λRn* � *<sup>λ</sup>Ra* <sup>≈</sup>*λRn*. Therefore, Eq. (6)

#### **2. Closed-can technique measurements**

#### **2.1 The buildup of radon concentration equation**

Since radon is produced continuously from decay of radium in natural decay chains of uranium, the rate of change of the number of radon atoms is determined by radon decay and generation of radon in the decay of radium present in closed can **Figure 1**. Since radium present as solid and radon as gas, in order to find the rate of change of the number of radon atoms in the air-filled pore space, assuming that [1, 4].


#### **Figure 1.** *Closed-can technique.*

nuclear tracks detectors to measure the radon concentration, radon exhalation rate, radium content and diffusion coefficient in the soil, building materials and water in laboratory. There are several names for this method, for example, diffusion chamber, accumulation chamber, radon exposure chamber, and time-integrated passive radon dosimeter and emanation container. Different types of cans are being used by different authors, this types is based on geometry ship (conical, cylindrical, hemispherical, and rectangular), dimensions (radius, height), and material. The can technique has some advantage, simple and efficient method, relatively inexpensive. The technique provides quite reliable measurements. One commonly used design is plastic Poly Vinyl Chloride (PVC) cylindrical can with different dimensions. The aim of this chapter will be to derive mathematical expressions, analysis and discussion, for the most of relationships of measuring the concentration of radon and

*Recent Techniques and Applications in Ionizing Radiation Research*

In this chapter, we will drive and discuss the theoretical formalism which used in the research work and a complete methodology. This chapter will include the detail description of drive the most important mathematical relationships used in technique radon measurements. The present work will help in understanding the status of indoor and outdoor radon, thoron and their progeny concentrations and status of the exhalation of these gases from soil. Classification of measurements is also included in this chapter. The necessary procedures and formulae involved in measuring the concentrations of radon, thoron and their progeny, the radioactivity content of samples along with the calculations of, exhalation rate, equilibrium factor, radon diffusion coefficient and other mathematical relationships are given in

Since radon is produced continuously from decay of radium in natural decay chains of uranium, the rate of change of the number of radon atoms is determined by radon decay and generation of radon in the decay of radium present in closed can **Figure 1**. Since radium present as solid and radon as gas, in order to find the rate of change of the number of radon atoms in the air-filled pore space, assuming

• The radium distributes uniformly in the surface soil and does not exist in the air.

• Radon transport in the soil is vertical and only due to diffusion and convection

• All radon produced in the solid material will escape (emanate) into the pore-air

• Radon-tight containers, no leakage of radon out of the can and no back

placed in the summary tables [1–3].

**2. Closed-can technique measurements**

• The soil column is homogeneous.

in the pore space.

diffusion effects.

space.

**72**

**2.1 The buildup of radon concentration equation**

• The radium is only present in soil and decay there.

• The radon production and decay in the air space.

this chapter.

that [1, 4].

Therefore, decay of radium and production of radon can be described by the rate equations for serial radioactive decay chain (Batman equations) [5]:

$$\frac{dN\_{Ra}}{dt} = -\lambda\_{Ra} N\_{Ra} \tag{1}$$

$$\frac{dN\_{Rn}}{dt} = \lambda\_{Ra} N\_{Ra} - \lambda\_{Rn} N\_{Rn} \tag{2}$$

where λRa, λRn is decay constant for radium and radon respectively. Τ*Ra* <sup>1</sup>*=*<sup>2</sup> ¼ 1600 *years*, Τ*Rn* <sup>1</sup>*=*<sup>2</sup> ¼ 3*:*824 *d*ays are the half-life for radium and radon respectively.

From Eqs. (1) and (2), we can determine the number of undecided radon atoms at a time t. By solving two equations, we will obtain the remaining number of radon atoms without decay at any time is:

$$N\_{Rn}(t) = N\_{Ra}(\mathbf{O})\,\lambda\_{Ra} \left(\frac{e^{-\lambda\_{Ra}t}}{\lambda\_{Rn} - \lambda\_{Ra}} + \frac{e^{-\lambda\_{Ra}t}}{\lambda\_{Ra} - \lambda\_{Rn}}\right) \tag{3}$$

or

$$N\_{Rn}(t) = \frac{\lambda\_{Ra}}{\lambda\_{Rn} - \lambda\_{Ra}} N\_{Rd}(\mathbf{0}) \left( e^{-\lambda\_{Rd}t} - e^{-\lambda\_{Rd}t} \right) \tag{4}$$

*NRa*ð Þ 0 , is the original number of radium atoms. The activity *A(t)* at time t is defined mathematically:

$$A(t) = \mathbb{X}N(t)\tag{5}$$

Eq. (5) becomes:

$$A\_{Rn}(t) = \frac{\lambda\_{Rn}}{\lambda\_{Rn} - \lambda\_{Rn}} A\_{Ra}(\mathbf{0}) \left( e^{-\lambda\_{Rd}t} - e^{-\lambda\_{Rd}t} \right) \tag{6}$$

Α*Ra*ð Þ 0 is original activity of radium which is constant value.

Since *TRa* 1 2 ≫ *TRn* 1 2 ! *<sup>λ</sup>Ra* <sup>≪</sup> *<sup>λ</sup>Ra* ! *<sup>e</sup>*�*λRat* <sup>≈</sup>1&*λRn* � *<sup>λ</sup>Ra* <sup>≈</sup>*λRn*. Therefore, Eq. (6) becomes:

$$A\_{Rn}(t) = A\_{Rn}(\mathbf{0}) \left(\mathbf{1} - e^{-\lambda\_{Rn}t}\right) \tag{7}$$

#### *Recent Techniques and Applications in Ionizing Radiation Research*

From Eq. (7) the activity of radon grows and becomes exactly the same with original activity of radium when time t passed many of the radon half-life (i.e. ≈ 27 *days*). In other word, radon atoms are decaying at the same rate at which they are formed. This is called secular equilibrium [5]. The secular equilibrium is important for the calculation of the activity concentration of radon in the can technique. This means that, the radon activity will reach maximum value or steady state value or equilibrium state value after 4 weeks time. This value is called sometimes the final activity or the saturated activity. In other words, we replaced *ΑRa*ð Þ 0 by steady state (final) activity of radon A*<sup>s</sup>* in Eq. (7) to become:

$$A\_{Rn}(t) = A\_s \left(1 - e^{-\lambda\_{Rn}t}\right) \tag{8}$$

*dρ*

*dρ*

*ρ* ¼ *K*

where *C t*ð Þ is radon concentration in air around the detector (Bq � <sup>m</sup>�<sup>3</sup>

C*<sup>I</sup>* ¼ ð T

*Cavg* <sup>¼</sup> <sup>1</sup> *T* ð *T*

2.We define the average radon concentration (Bq � <sup>m</sup>�<sup>3</sup>

3.The radon concentration at steady state value Cs is:

From Eqs. (15) and (16), we obtain:

From Eqs. (15) and (18), we get:

tracks for radon concentration.

**75**

0

<sup>C</sup>*<sup>I</sup>* <sup>¼</sup> <sup>ρ</sup>

0

*Cavg* <sup>¼</sup> *<sup>ρ</sup>*

*Cs* <sup>¼</sup> *<sup>ρ</sup> K T*27*<sup>d</sup>*

This means that, the detector should be exposed for at least 27 day to record

integrate Eq. (14), we obtain with initial condition *ρ*ð Þ¼ 0 0:

*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

The proportionality constant, is called the calibration factor of the detector or conversional factor or response factor or turned over sensitivity factor [1]. It convert the track density (Track � cm�2) to exposure concentration (Bq � <sup>m</sup>�<sup>3</sup> � day). By

> ð *T*

0

and *T* is the total exposure time (day). There are five cases, we can discuss than blow:

1.The radon concentration is proportion to along exposure time. In this state, the track density measured the integrated concentration and not concentration instantaneous or the final concentration. Sometimes, it is called accumulation concentration or exposure concentration. The integrated radon concentration <sup>C</sup>*<sup>I</sup>* (*Bq* � *<sup>m</sup>*�<sup>3</sup>� day) after a period of time *<sup>T</sup>* is defined mathematically as [1]:

or

*dt* <sup>∝</sup>*C t*ð Þ (13)

*dt* <sup>¼</sup> *KC t*ð Þ (14)

*C t*ð Þ *dt* (15)

C tð Þ dt (16)

<sup>K</sup> (17)

*C t*ð Þ *dt* (18)

*K T* (19)

) by the expression of:

(20)

) at time *t*

Eq. (8) describes the buildup of radon activity through time t. If *V* is the volume of air-filled space within can, the activity concentration of radon *C Bq* � *<sup>m</sup>*�<sup>3</sup> ð Þ in the air volume of the can given by the following relation [2, 3]:

$$\mathbf{C} = \frac{A\_{Rn}}{V} = \frac{\lambda\_{Rn} N\_{Rn}}{V} \tag{9}$$

Eq. (9) becomes:

$$\mathbf{C}(t) = \mathbf{C}\_{\mathbf{t}} \left(\mathbf{1} - e^{-\lambda\_{\text{Re}}t}\right) \tag{10}$$

Where *C t*ð Þ is the radon concentration at time *t Bq* � *<sup>m</sup>*�<sup>3</sup> ð Þ, *Cs* is the steady state (final) concentration *Bq* � *<sup>m</sup>*�<sup>3</sup> ð Þ. Eq. (10) is the well-known equation which describes the buildup of the concentration of radon emanated from each sample inside the exhalation container with time [1, 6].

#### **2.2 Track density-radon concentration relation**

Since the alpha particles emitted by 222Rn and its progeny strike the detectors and leave latent tracks in it, Solid State Nuclear Detector measures the total number of alpha-disintegration in unit volume of the can during the exposure time. The tracks can be visible by chemical or electrochemical etching. The main measured quantity is the track density, which is the total tracks per unit area of detector, i.e. [1].

$$
\rho = \frac{N\_{\text{total\\_track}}}{A\_D} \tag{11}
$$

where *<sup>ρ</sup>* is the track density expressed in Track � cm�<sup>2</sup> ð Þ, *AD* is the area of detector in (cm2 ). Since the etching track is observed and accounted by using optical microscope, and when looking into a microscope, we will see a lit circular area called field of view. The field of view (FOV) is the maximum area visible through the lenses of a microscope, and it is represented by a diameter. Therefore, we divide the area of detector to *n* of the field of view *AFOV*. Eq. (11) becomes:

$$\rho = \frac{N\_{\text{total\\_track}}}{n\text{ }A\_{FOV}} = \frac{N\_{\text{avg}}}{A\_{FOV}} \tag{12}$$

where *n* the number of fields is, Navg is the average of total tracks and AFOV is the area of the field of view (cm<sup>2</sup> ). The measured track density rate recorded on the SSNTD is proportional to the radon concentration during the time of exposure [7].

*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

$$\frac{d\rho}{dt} \text{ocC}(t) \tag{13}$$

or

From Eq. (7) the activity of radon grows and becomes exactly the same with original activity of radium when time t passed many of the radon half-life (i.e. ≈ 27 *days*). In other word, radon atoms are decaying at the same rate at which they are formed. This is called secular equilibrium [5]. The secular equilibrium is important for the calculation of the activity concentration of radon in the can technique. This means that, the radon activity will reach maximum value or steady state value or equilibrium state value after 4 weeks time. This value is called sometimes the final activity or the saturated activity. In other words, we replaced *ΑRa*ð Þ 0 by steady

*ARn*ðÞ¼ *t As* 1 � *e*

*<sup>C</sup>* <sup>¼</sup> *ARn*

*C t*ðÞ¼ *Cs* 1 � *e*

(final) concentration *Bq* � *<sup>m</sup>*�<sup>3</sup> ð Þ. Eq. (10) is the well-known equation which describes the buildup of the concentration of radon emanated from each sample

Eq. (8) describes the buildup of radon activity through time t. If *V* is the volume of air-filled space within can, the activity concentration of radon *C Bq* � *<sup>m</sup>*�<sup>3</sup> ð Þ in the

*<sup>V</sup>* <sup>¼</sup> *<sup>λ</sup>RnNRn*

Where *C t*ð Þ is the radon concentration at time *t Bq* � *<sup>m</sup>*�<sup>3</sup> ð Þ, *Cs* is the steady state

Since the alpha particles emitted by 222Rn and its progeny strike the detectors and leave latent tracks in it, Solid State Nuclear Detector measures the total number of alpha-disintegration in unit volume of the can during the exposure time. The tracks can be visible by chemical or electrochemical etching. The main measured quantity is the track density, which is the total tracks per unit area of

> *<sup>ρ</sup>* <sup>¼</sup> *Ntotal track AD*

). Since the etching track is observed and accounted by using

<sup>¼</sup> *Navg AFOV*

). The measured track density rate recorded on the

where *n* the number of fields is, Navg is the average of total tracks and AFOV is the

SSNTD is proportional to the radon concentration during the time of exposure [7].

where *<sup>ρ</sup>* is the track density expressed in Track � cm�<sup>2</sup> ð Þ, *AD* is the area of

optical microscope, and when looking into a microscope, we will see a lit circular area called field of view. The field of view (FOV) is the maximum area visible through the lenses of a microscope, and it is represented by a diameter. Therefore, we divide the area of detector to *n* of the field of view *AFOV*. Eq. (11) becomes:

> *<sup>ρ</sup>* <sup>¼</sup> *Ntotal track n AFOV*

�*λRnt* (8)

*<sup>V</sup>* (9)

(11)

(12)

�*λRnt* (10)

state (final) activity of radon A*<sup>s</sup>* in Eq. (7) to become:

*Recent Techniques and Applications in Ionizing Radiation Research*

air volume of the can given by the following relation [2, 3]:

inside the exhalation container with time [1, 6].

**2.2 Track density-radon concentration relation**

Eq. (9) becomes:

detector, i.e. [1].

detector in (cm2

**74**

area of the field of view (cm<sup>2</sup>

$$\frac{d\rho}{dt} = K \text{ C(t)}\tag{14}$$

The proportionality constant, is called the calibration factor of the detector or conversional factor or response factor or turned over sensitivity factor [1]. It convert the track density (Track � cm�2) to exposure concentration (Bq � <sup>m</sup>�<sup>3</sup> � day). By integrate Eq. (14), we obtain with initial condition *ρ*ð Þ¼ 0 0:

$$\rho = K \int\_0^T \mathbf{C}(t) \, dt \tag{15}$$

where *C t*ð Þ is radon concentration in air around the detector (Bq � <sup>m</sup>�<sup>3</sup> ) at time *t* and *T* is the total exposure time (day). There are five cases, we can discuss than blow:

1.The radon concentration is proportion to along exposure time. In this state, the track density measured the integrated concentration and not concentration instantaneous or the final concentration. Sometimes, it is called accumulation concentration or exposure concentration. The integrated radon concentration <sup>C</sup>*<sup>I</sup>* (*Bq* � *<sup>m</sup>*�<sup>3</sup>� day) after a period of time *<sup>T</sup>* is defined mathematically as [1]:

$$\mathbf{C}\_{I} = \int\_{0}^{\mathbf{T}} \mathbf{C}(\mathbf{t}) \, \mathbf{d}\mathbf{t} \tag{16}$$

From Eqs. (15) and (16), we obtain:

$$\mathbf{C}\_{I} = \frac{\rho}{\mathbf{K}} \tag{17}$$

2.We define the average radon concentration (Bq � <sup>m</sup>�<sup>3</sup> ) by the expression of:

$$\mathbf{C}\_{\text{avg}} = \frac{1}{T} \int\_{0}^{T} \mathbf{C}(t) \, dt \tag{18}$$

From Eqs. (15) and (18), we get:

$$\mathbf{C}\_{\text{avg}} = \frac{\rho}{K \, T} \tag{19}$$

3.The radon concentration at steady state value Cs is:

$$\mathbf{C}\_{s} = \frac{\rho}{\mathbf{K} \, T\_{27d}} \tag{20}$$

This means that, the detector should be exposed for at least 27 day to record tracks for radon concentration.


area of sample from which the exhalation takes place), λ is the decay constant of

equation of reference [2, 3], that we added to the equation Eq. (21) to unify the units on both sides of the equation. The solution of Eq. (21) with initial condition

volume of the can as a function of time t that can be given by the following relation

*N t*ðÞ¼ *EAA<sup>τ</sup> λ*

*C t*ðÞ¼ *A t*ð Þ

*C t*ðÞ¼ *EA <sup>A</sup> <sup>τ</sup> V*

*C t*ðÞ¼ *EA <sup>A</sup> λV*

By integrating on sides of equation for time, we get:

At steady state (secular equilibrium), *dN t*ð Þ

*But <sup>τ</sup>*ð Þ¼ *<sup>h</sup>* <sup>1</sup>

*CI* <sup>¼</sup> *E A*

So, the exhalation radon rate as a function radon integrated concentration is

*EA* <sup>¼</sup> *CI <sup>λ</sup> <sup>V</sup> A Teff*

*EA* <sup>¼</sup> *Cs <sup>λ</sup> <sup>V</sup>*

And the exhalation radon rate as a function average radon concentration is

*EA* <sup>¼</sup> *Cavg <sup>λ</sup> V T A Teff*

From Eqs. (19) and (30), we get the exhalation rate as a function to the tracks

*EA* <sup>¼</sup> *ρ λ <sup>V</sup> KA Teff*

) and *τ* is the live time of radon (h). The quantity *τ* does not exist in

1 � *e*

*<sup>V</sup>* <sup>¼</sup> *<sup>λ</sup> N t*ð Þ

1 � *e*

1 � *e*

�*λ<sup>t</sup>* (22)

*<sup>V</sup>* (23)

�*λ<sup>t</sup>* (24)

*<sup>λ</sup> <sup>h</sup>*�<sup>1</sup> (25)

�*λ<sup>t</sup>* (26)

*<sup>λ</sup><sup>V</sup> Teff* (27)

*dt* ¼ 0 *and Teff* ¼ *T*, we get:

*<sup>A</sup>* (29)

(28)

(30)

(31)

), the activity concentration of radon *C*(*t*) in the air

radon (h�<sup>1</sup>

Eq. (23):

given by:

given by:

density:

**77**

*N*(*0*) = *0* is Eq. (22):

If *V* is the volume of air (m<sup>3</sup>

*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

The equation becomes:

**Table 1.**

*Radon concentration in different quantities.*

The results lead to the following remarks [1]:


#### **2.3 Radon exhalation rate equation**

When radium decay in soil, the resulting atoms of radon isotopes first escapes from the mineral to air-filled pores. Being a noble gas, 222Rn can move large distances through rocks and soils. Radon can diffuse through rocks and soil, can move from one place to the other and can leak out in the atmosphere from the soil. The exhalation of radon from soil involves two mechanisms, the emanation and transport. The measurement of radon exhalation rate in soil is helpful to study radon health hazard. The passive measuring techniques "Can Technique" employing a Solid State Nuclear Track Detector (SSNTDs), a simple and efficient method to assess radon exhalation rates besides being relatively inexpensive, the technique provides quite reliable measurements. The exhalation rate is defined as the rate at which radon escapes from soil into the surrounding air. This may be measured by either per unit area or per unit mass of sample. Consider a sealed cylindrical can fitted with a source of radon and a SSNTD dosimeter fixed at the top of the can. Assume that radon, thoron and their daughters are in radioactive equilibrium in the air volume of the can. For diffusion in air, it is expected that all daughters of interest will be deposited except 216Po will be in air volume. Furthermore, 220Rn and 216Po are in homogenously distributed in the air due to their short half-lives. The 212Po and 212Bi formed by the decay of 216Po will be preferentially in homogenously deposited on the wall of the can. It is clear that the track density is registered on the detector which is related to 222Rn, as well as its plated-out daughters. The exhalation of radon from the sample surface represents the source of the number of radon atoms *N*(*t*), present in the air between the sample and SSNTD Which is directly proportional to area of surface and life time for radon. The natural decay of radon provides the only removal mechanism. The rate of change of *N*(*t*) with time is therefore governed by the following differential Eq. (21) [1–3]:

$$\frac{dN(t)}{dt} = E\_A A \tau - \lambda \, N(t) \tag{21}$$

where *N*(*t*) is the total number of radon atoms present in the can at time *t*, *E* is the exhalation rate (Bq � <sup>m</sup>�<sup>2</sup> � <sup>h</sup>�<sup>1</sup> ), *A* is cross-sectional area of the can (the surface *Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

area of sample from which the exhalation takes place), λ is the decay constant of radon (h�<sup>1</sup> ) and *τ* is the live time of radon (h). The quantity *τ* does not exist in equation of reference [2, 3], that we added to the equation Eq. (21) to unify the units on both sides of the equation. The solution of Eq. (21) with initial condition *N*(*0*) = *0* is Eq. (22):

$$N(t) = \frac{E\_A A \tau}{\lambda} \text{ (1}-e^{-\lambda t} \text{)}\tag{22}$$

If *V* is the volume of air (m<sup>3</sup> ), the activity concentration of radon *C*(*t*) in the air volume of the can as a function of time t that can be given by the following relation Eq. (23):

$$\mathbf{C}(t) = \frac{\mathbf{A}(t)}{V} = \frac{\lambda \, N(t)}{V} \tag{23}$$

The equation becomes:

The results lead to the following remarks [1]:

concentration as shown in **Table 1**.

large exposure time.

**Integrated concentration** *CI* **(Bq** � **<sup>m</sup>**�**<sup>3</sup>** � **day)**

*Radon concentration in different quantities.*

*ρ K*

**Table 1.**

**2.3 Radon exhalation rate equation**

(*t* ffi 7*T*1*<sup>=</sup>*2) regardless of the volume of the container.

*ρ K T*

*Recent Techniques and Applications in Ionizing Radiation Research*

therefore governed by the following differential Eq. (21) [1–3]:

the exhalation rate (Bq � <sup>m</sup>�<sup>2</sup> � <sup>h</sup>�<sup>1</sup>

**76**

*dN t*ð Þ

where *N*(*t*) is the total number of radon atoms present in the can at time *t*, *E* is

*dt* <sup>¼</sup> *EAA<sup>τ</sup>* � *<sup>λ</sup> N t*ð Þ (21)

), *A* is cross-sectional area of the can (the surface

1.The radon concentration reaches the equilibrium state at the same time

**Average concentration Cavg (Bq** � **<sup>m</sup>**�**<sup>3</sup>**

**)**

**Steady state concentration**

**)**

**Cs (Bq** � **<sup>m</sup>**�**<sup>3</sup>**

*ρ K T*27*<sup>d</sup>*

2.There are three different quantities measured by track density, integrated radon concentration, average radon concentration and saturate radon

3.The average radon concentration equal to the saturate radon concentration at

When radium decay in soil, the resulting atoms of radon isotopes first escapes from the mineral to air-filled pores. Being a noble gas, 222Rn can move large distances through rocks and soils. Radon can diffuse through rocks and soil, can move from one place to the other and can leak out in the atmosphere from the soil. The exhalation of radon from soil involves two mechanisms, the emanation and transport. The measurement of radon exhalation rate in soil is helpful to study radon health hazard. The passive measuring techniques "Can Technique" employing a Solid State Nuclear Track Detector (SSNTDs), a simple and efficient method to assess radon exhalation rates besides being relatively inexpensive, the technique provides quite reliable measurements. The exhalation rate is defined as the rate at which radon escapes from soil into the surrounding air. This may be measured by either per unit area or per unit mass of sample. Consider a sealed cylindrical can fitted with a source of radon and a SSNTD dosimeter fixed at the top of the can. Assume that radon, thoron and their daughters are in radioactive equilibrium in the air volume of the can. For diffusion in air, it is expected that all daughters of interest will be deposited except 216Po will be in air volume. Furthermore, 220Rn and 216Po are in homogenously distributed in the air due to their short half-lives. The 212Po and 212Bi formed by the decay of 216Po will be preferentially in homogenously deposited on the wall of the can. It is clear that the track density is registered on the detector which is related to 222Rn, as well as its plated-out daughters. The exhalation of radon from the sample surface represents the source of the number of radon atoms *N*(*t*), present in the air between the sample and SSNTD Which is directly proportional to area of surface and life time for radon. The natural decay of radon provides the only removal mechanism. The rate of change of *N*(*t*) with time is

$$C(t) = \frac{E\_A A \text{ } \tau}{V} \text{ } (1 - e^{-\lambda t}) \tag{24}$$

$$\text{But } \pi(h) = \frac{1}{\lambda(h^{-1})} \tag{25}$$

$$\mathbf{C}(t) = \frac{E\_A \ A}{\lambda V} \ (\mathbf{1} - e^{-\lambda t}) \tag{26}$$

By integrating on sides of equation for time, we get:

$$C\_I = \frac{EA}{\lambda V} T\_{\text{eff}} \tag{27}$$

So, the exhalation radon rate as a function radon integrated concentration is given by:

$$E\_A = \frac{C\_I \lambda}{A} \frac{V}{T\_{\text{eff}}} \tag{28}$$

At steady state (secular equilibrium), *dN t*ð Þ *dt* ¼ 0 *and Teff* ¼ *T*, we get:

$$E\_A = \frac{C\_\text{s} \lambda^\text{ } V}{A} \tag{29}$$

And the exhalation radon rate as a function average radon concentration is given by:

$$E\_A = \frac{C\_{\text{avg}} \,\lambda \, V \, T}{A \, T\_{\text{eff}}} \tag{30}$$

From Eqs. (19) and (30), we get the exhalation rate as a function to the tracks density:

$$E\_A = \frac{\rho \text{ } \lambda \text{ } V}{\text{KA } T\_{\text{eff}}} \tag{31}$$

By the same method we get the mass exhalation rate, where *M* is the mass of sample in container:

$$\begin{array}{c} E\_{\mathcal{M}} = \frac{\mathcal{C}\_{I}\lambda\mathcal{V}}{\mathcal{M}^{\mathcal{T}\_{eff}}}\\ E\_{\mathcal{M}} = \frac{\mathcal{C}\_{\mathcal{S}}\mathcal{T}\lambda\mathcal{V}}{\mathcal{M}\mathcal{T}\_{eff}}\\ E\_{\mathcal{M}} = \frac{\mathcal{C}\_{avg}\lambda\mathcal{V}\mathcal{T}}{\mathcal{M}\mathcal{T}\_{eff}}\\ E\_{\mathcal{M}} = \frac{\rho\lambda\mathcal{V}}{\mathcal{M}\mathcal{T}\_{eff}} \end{array} \tag{32}$$

<sup>C</sup>*Ra* <sup>¼</sup> *<sup>ρ</sup> A h K MTeff*

**2.5 Closed-can technique (two different detectors)**

*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

progenies have bombarded the SSNTD films [1, 8].

*ρG*

*ρG*

*EA Bq m*�<sup>2</sup> *<sup>h</sup>*�<sup>1</sup> <sup>¼</sup> *CI <sup>λ</sup> <sup>V</sup>*

*EM Bq kg*�<sup>1</sup> *<sup>h</sup>*�<sup>1</sup> <sup>¼</sup> *CI <sup>λ</sup> <sup>V</sup>*

<sup>C</sup>*Ra Bq kg*�<sup>1</sup> <sup>¼</sup> *CIV*

*The exhalation radon rate formulize.*

**Table 2.**

**79**

dividing right hand-Eq. (42) *CRn*, we obtain:

*Rn* ¼ *KRn* þ *KPo*<sup>218</sup>

*A Teff*

*M Teff*

*MTeff*

*ρG*

the CR-39 detector *ρ<sup>G</sup>*

Since the unit of time in exhalation formula in hour, we should convert units of *λ*, *Teff* and *K* to hour. All the quantities in **Table 2** are known except (*CI, C, Cavg*). We can find *ρ* experimentally by using CR-39 or LR-115 type II based on radon dosimeter and by using continuous radon monitor to determine the value of (*CI, C, Cavg*). From **Table 2**, we show that the quantities (*λ*, *T*, *Teff* , *K*, *M*, *A*,*V*Þ are constants, therefore the relationship between radon exhalation rate and effective radium content with the quantities (*CI, C, Cavg*, *ρ*) are linear. From the relations in **Table 2**, we get some relations which show the ship linear between these quantities [1]:

In this technique using two different SSNTD detectors (CR-39 & LR-II) were separately placed in close-can, to measurement and discriminate between radon and thoron concentrations which escape from sample, at same time **Figure 2**. During this exposure the α-particles emitted by the nuclei of radon and thoron and its

The global track density rates, due to α-particles emitted by radon, registered on

where *ρ<sup>i</sup>* are the track density for radon and its progenies on CR-39 detectors and

where *Ki* are the calibration factors for radon and its progenies. By malty and

*CPo*<sup>218</sup> *CRn*

**Quantity** *CI C***<sup>s</sup>** *C*avg *ρ*

*Cs λ V A*

*Cs λ V M*

> *Cs V M*

from Eq. (19) can written by concentration average of radon and its progenies:

*Rn* ¼ *ρRn* þ *ρPo*<sup>218</sup> þ *ρPo*<sup>214</sup> (41)

*CPo*<sup>218</sup> *CRn CRnT* (43)

> *CavgT λ V A Teff*

> *CavgT λ V M Teff*

> > *CavgT V MTeff*

*ρ λ V KA Teff*

*ρ λ V KMTeff*

*ρ V K MTeff*

*Rn* ¼ *KRnCRn T* þ *KPo*218*CPo*218*T* þ *KPo*214*CPo*214*T* (42)

þ *KPo*<sup>214</sup>

*Rn* can be writing mathematical:

(39)

ð40Þ

#### **2.4 Radium content calculation**

Since the half-life of radium is 1600 years and that of radon is 3.82 days, it is reasonable to assume that an effective equilibrium (about 98%) for radium-radon members of the decay series is reached to about three weeks or more. Once the radioactive equilibrium is established, one may use the radon alpha analysis for the determination of steady state activity concentration of radium. The activity concentration of radon begins to increase with time *t*, after the closing of the can, according to the relation Eq. (7) [1]:

$$\mathbf{A}\_{Rn}(t) = \mathbf{A}\_{Ra} \left(\mathbf{1} - e^{-\lambda\_{Rn}t}\right) \tag{33}$$

By dividing Eq. (33) on the volume of radon, we get on the activity concentration of radon:

$$\mathbf{C}\_{\text{Rn}}(t) = \frac{\mathbf{A}\_{\text{Ra}}}{V} \left(\mathbf{1} - e^{-\lambda\_{\text{Ra}}t}\right) \tag{34}$$

By multi Eq. (34) by dt and integrated for exposure time *T*, we get:

$$\mathbf{A}\_{Ra} = \frac{C\_I V}{T\_{\text{eff}}} \tag{35}$$

By dividing Eq. (35) on mass of sample, we get:

$$\mathbf{C}\_{Ra} = \frac{C\_I V}{\mathbf{M} T\_{eff}} \tag{36}$$

where C*Ra* is effective radium content in unite (Bq/kg):

$$\mathbf{C}\_{Ra} = \frac{\mathbf{A}\_{Ra}}{M} \tag{37}$$

By average radon concentration, we get:

$$\mathbf{C}\_{Ra} = \frac{\mathbf{C}\_{avg} T \, V}{M T\_{eff}} \tag{38}$$

From Eqs. (19) and (38) we get the effective radium content as a function to the tracks density:

*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

By the same method we get the mass exhalation rate, where *M* is the mass of

*Recent Techniques and Applications in Ionizing Radiation Research*

Since the half-life of radium is 1600 years and that of radon is 3.82 days, it is reasonable to assume that an effective equilibrium (about 98%) for radium-radon members of the decay series is reached to about three weeks or more. Once the radioactive equilibrium is established, one may use the radon alpha analysis for the

determination of steady state activity concentration of radium. The activity concentration of radon begins to increase with time *t*, after the closing of the can,

Α*Rn*ðÞ¼ *t* Α*Ra* 1 � *e*

C*Rn*ðÞ¼ *t*

By dividing Eq. (35) on mass of sample, we get:

By average radon concentration, we get:

where C*Ra* is effective radium content in unite (Bq/kg):

By multi Eq. (34) by dt and integrated for exposure time *T*, we get:

By dividing Eq. (33) on the volume of radon, we get on the activity concentra-

Α*Ra <sup>V</sup>* <sup>1</sup> � *<sup>e</sup>*

<sup>Α</sup>*Ra* <sup>¼</sup> *CIV Teff*

<sup>C</sup>*Ra* <sup>¼</sup> *CIV MTeff*

<sup>C</sup>*Ra* <sup>¼</sup> <sup>Α</sup>*Ra*

<sup>C</sup>*Ra* <sup>¼</sup> *CavgT V MTeff*

From Eqs. (19) and (38) we get the effective radium content as a function to the

�*λRnt* (33)

�*λRnt* (34)

*<sup>M</sup>* (37)

ð32Þ

(35)

(36)

(38)

sample in container:

**2.4 Radium content calculation**

according to the relation Eq. (7) [1]:

tion of radon:

tracks density:

**78**

$$\mathbf{C}\_{\text{Rat}} = \frac{\rho \, A \, h}{K \, MT\_{\text{eff}}} \tag{39}$$

Since the unit of time in exhalation formula in hour, we should convert units of *λ*, *Teff* and *K* to hour. All the quantities in **Table 2** are known except (*CI, C, Cavg*). We can find *ρ* experimentally by using CR-39 or LR-115 type II based on radon dosimeter and by using continuous radon monitor to determine the value of (*CI, C, Cavg*). From **Table 2**, we show that the quantities (*λ*, *T*, *Teff* , *K*, *M*, *A*,*V*Þ are constants, therefore the relationship between radon exhalation rate and effective radium content with the quantities (*CI, C, Cavg*, *ρ*) are linear. From the relations in **Table 2**, we get some relations which show the ship linear between these quantities [1]:

$$\begin{pmatrix} \frac{E\_A}{E\_M} = \frac{\mathcal{M}}{A} \\ \frac{E\_A}{C\_{Ra}} = \lambda \frac{\mathcal{M}}{A} \\ \frac{E\_M}{C\_{Ra}} = \lambda \end{pmatrix} \tag{40}$$

#### **2.5 Closed-can technique (two different detectors)**

In this technique using two different SSNTD detectors (CR-39 & LR-II) were separately placed in close-can, to measurement and discriminate between radon and thoron concentrations which escape from sample, at same time **Figure 2**. During this exposure the α-particles emitted by the nuclei of radon and thoron and its progenies have bombarded the SSNTD films [1, 8].

The global track density rates, due to α-particles emitted by radon, registered on the CR-39 detector *ρ<sup>G</sup> Rn* can be writing mathematical:

$$
\rho\_{\rm Rn}^G = \rho\_{\rm Rn} + \rho\_{\rm Po218} + \rho\_{\rm Po214} \tag{41}
$$

where *ρ<sup>i</sup>* are the track density for radon and its progenies on CR-39 detectors and from Eq. (19) can written by concentration average of radon and its progenies:

$$
\rho\_{Rn}^G = K\_{Rn} C\_{Rn} \ T + K\_{Po218} C\_{Po218} T + K\_{Po214} C\_{Po214} T \tag{42}
$$

where *Ki* are the calibration factors for radon and its progenies. By malty and dividing right hand-Eq. (42) *CRn*, we obtain:

$$
\rho\_{Rn}^G = \left( K\_{Rn} + K\_{Po218} \frac{C\_{Po218}}{C\_{Rn}} + K\_{Po214} \frac{C\_{Po218}}{C\_{Rn}} \right) C\_{Rn} T \tag{43}
$$


**Table 2.**

*The exhalation radon rate formulize.*

#### **Figure 2.**

*Closed-can technique (two different detectors).*

At radioactive secular equilibrium between radon and its progenies, i.e.:

$$\frac{\mathbf{C}\_{\text{Po218}}}{\mathbf{C}\_{\text{Rn}}} = \frac{\mathbf{C}\_{\text{Po214}}}{\mathbf{C}\_{\text{Rn}}} = \mathbf{1} \tag{44}$$

where:

**81**

*ρCR*: Tracks density registration on CR-39 detector. *ρLR*: Tracks density registration on LR-115(II) detector. *KRC*: Calibration factor of radon for CR-39 detector. *KRL*: Calibration factor of radon for LR-115(II) detector. *KTC*: Calibration factor of thoron for CR-39 detector. *KTL*: Calibration factor of thoron for LR-115(II) detector.

*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

Emin and Emax), this mean *ρ<sup>r</sup>* > 1 [9].

**3. Indoor radon technique measurements**

Since, *Cr* is positive quantity, the CR-LR track density ratio should be *KRn* <*ρ<sup>r</sup>* <*KTh* and *KTh* >*KRn.* Since, *ρCR* > *ρLR*, because CR-39 recorders all alpha particles energies, while LR-II detector recorders window energies (i.e. between

Radon and thoron present in outdoor and indoor air as they exhaled from soil and building materials of the walls, floor and ceilings. It is critically important that inhalation of radon and their progeny concentrations has been shown experimentally to cause lung cancer in rats and observed to cause lung cancer in men exposed to large amounts in the air of mines. Several techniques have been developed to measure radon indoors. The use of a Solid State Nuclear Track Detector (SSNTD) closed in a cup mode (passive dosimeters) and bare mode has turned out to be the most appropriate for long term measurements. Radon measurement with, bare (open) detector are rough and with rather high uncertainties. Some device of cup mode have single chamber called invented cup. In twin cup mode, the detectors are kept inside a twin cup dosimeter, a cylindrical plastic chamber divided into two equal compartments. The two equal compartments on both sides are filter and pinhole compartments. There is one small compartment at the external middle attached to it which is used for bare mode exposure as shown in **Figure 3** [1, 10, 11]. This design of the dosimeter was well suited to discriminate 222Rn and 220Rn in mixed field situations, where both gases are present. SSNTDs were used as detectors

and affixed at the bottom of each cup as well as on the outer surface of the dosimeter. The exposure of the detector inside the cup is termed as cup mode and the one exposed open is termed as the bare mode. One of the cups had its entry covered with a glass fiber filter paper that permits both 222Rn and 220Rn gases into the cup and is called the filter cup. The other cup was covered with a soft sponge and is called the sponge cup. SSNTDs film inside the sponge cup registers tracks contributed by 222Rn only, while that in the filter cup records tracks due to 222Rn

ð50Þ

ð51Þ

ð52Þ

Eq. (43) becomes:

$$
\rho\_{Rn}^G = K\_{Rn} \mathbf{C}\_{Rn} T \tag{45}
$$

where

$$K\_{R\text{\tiny{}^\circ C}} = K\_{R\text{\tiny{}^\circ C}} + K\_{P\text{\tiny{}^\circ 218}} + K\_{P\text{\tiny{}^\circ 214}} \tag{46}$$

By same procedure, we find *ρ<sup>G</sup> Th* for thoron on CR-39 detector. The total track density *ρCR* for radon and thoron become:

$$
\rho\_{\text{CR}} = \rho\_{\text{Ru}}^{\text{G}} + \rho\_{\text{Th}}^{\text{G}} = K\_{\text{RC}} \mathbf{C}\_{\text{Ru}} T + K\_{\text{TC}} \mathbf{C}\_{\text{Th}} T \tag{47}
$$

The final result, we obtain tow equation description relationship between the radon and thoron concentration and tack density on CR-39 and LR-II detectors:

$$
\begin{bmatrix}
\rho\_{CR} = \begin{array}{c} K\_{RC} \ T \ C\_{Rn} + K\_{TC} \ TC\_{Th} \\ K\_{RL} = K\_{RL} \ T \ C\_{Rn} + K\_{TL} \ T \ C\_{Th}
\end{array} \tag{48}
$$

This are tow algebraic liner equations by tow variables *CRn* and *CTh*, the general solution for this are:

$$\mathcal{C}\_{Rn} = \frac{K\_{TL}\rho\_{CR} - K\_{TC}\rho\_{LR}}{K\_{RC}K\_{TL} - K\_{RL}K\_{TC}}$$

$$\mathcal{C}\_{Th} = \frac{K\_{RL}\rho\_{CR} - K\_{RC}\rho\_{LR}}{K\_{RL}K\_{TC} - K\_{RC}K\_{TL}}\tag{49}$$

After performing a series of mathematical simplifications, we obtain mathematical relationships to calculate concentrations for radon and thoron as function to tracks density *ρr*, radon-thoron concentrations *Cr* and calibration factors (*KL*,*KRn*,*KTh*,*KL*) ratio.

*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

ð50Þ

$$\begin{array}{ccl} \mathcal{C}\_r = \left. K\_L \left( \frac{\rho\_r - \kappa\_{Rn}}{\kappa\_{Th} - \rho\_r} \right) \right| \\ \rho\_r = \frac{\rho\_{CR}}{\rho\_{LR}} \end{array} \tag{51}$$

$$\begin{bmatrix} K\_{Rn} = \frac{K\_{RC}}{K\_{RL}}\\ K\_{Th} = \frac{K\_{TC}}{K\_{TL}}\\ K\_L = \frac{K\_{RL}}{K\_{TL}} \end{bmatrix} \tag{52}$$

where:

At radioactive secular equilibrium between radon and its progenies, i.e.:

<sup>¼</sup> *CPo*<sup>214</sup> *CRn*

The final result, we obtain tow equation description relationship between the radon and thoron concentration and tack density on CR-39 and LR-II detectors:

This are tow algebraic liner equations by tow variables *CRn* and *CTh*, the general

After performing a series of mathematical simplifications, we obtain mathematical relationships to calculate concentrations for radon and thoron as function to

tracks density *ρr*, radon-thoron concentrations *Cr* and calibration factors

¼ 1 (44)

*Rn* ¼ *KRnCCRnT* (45)

*KRnC* ¼ *KRn* þ *KPo*<sup>218</sup> þ *KPo*<sup>214</sup> (46)

*Th* for thoron on CR-39 detector. The total track

*Th* ¼ *KRCCRnT* þ *KTCCThT* (47)

ð48Þ

ð49Þ

*CPo*<sup>218</sup> *CRn*

*Recent Techniques and Applications in Ionizing Radiation Research*

*ρG*

Eq. (43) becomes:

*Closed-can technique (two different detectors).*

By same procedure, we find *ρ<sup>G</sup>*

density *ρCR* for radon and thoron become:

*<sup>ρ</sup>CR* <sup>¼</sup> *<sup>ρ</sup><sup>G</sup>*

*Rn* <sup>þ</sup> *<sup>ρ</sup><sup>G</sup>*

where

**Figure 2.**

solution for this are:

(*KL*,*KRn*,*KTh*,*KL*) ratio.

**80**

*ρCR*: Tracks density registration on CR-39 detector.

*ρLR*: Tracks density registration on LR-115(II) detector.

*KRC*: Calibration factor of radon for CR-39 detector.

*KRL*: Calibration factor of radon for LR-115(II) detector.

*KTC*: Calibration factor of thoron for CR-39 detector.

*KTL*: Calibration factor of thoron for LR-115(II) detector.

Since, *Cr* is positive quantity, the CR-LR track density ratio should be *KRn* <*ρ<sup>r</sup>* <*KTh* and *KTh* >*KRn.* Since, *ρCR* > *ρLR*, because CR-39 recorders all alpha particles energies, while LR-II detector recorders window energies (i.e. between Emin and Emax), this mean *ρ<sup>r</sup>* > 1 [9].

#### **3. Indoor radon technique measurements**

Radon and thoron present in outdoor and indoor air as they exhaled from soil and building materials of the walls, floor and ceilings. It is critically important that inhalation of radon and their progeny concentrations has been shown experimentally to cause lung cancer in rats and observed to cause lung cancer in men exposed to large amounts in the air of mines. Several techniques have been developed to measure radon indoors. The use of a Solid State Nuclear Track Detector (SSNTD) closed in a cup mode (passive dosimeters) and bare mode has turned out to be the most appropriate for long term measurements. Radon measurement with, bare (open) detector are rough and with rather high uncertainties. Some device of cup mode have single chamber called invented cup. In twin cup mode, the detectors are kept inside a twin cup dosimeter, a cylindrical plastic chamber divided into two equal compartments. The two equal compartments on both sides are filter and pinhole compartments. There is one small compartment at the external middle attached to it which is used for bare mode exposure as shown in **Figure 3** [1, 10, 11].

This design of the dosimeter was well suited to discriminate 222Rn and 220Rn in mixed field situations, where both gases are present. SSNTDs were used as detectors and affixed at the bottom of each cup as well as on the outer surface of the dosimeter. The exposure of the detector inside the cup is termed as cup mode and the one exposed open is termed as the bare mode. One of the cups had its entry covered with a glass fiber filter paper that permits both 222Rn and 220Rn gases into the cup and is called the filter cup. The other cup was covered with a soft sponge and is called the sponge cup. SSNTDs film inside the sponge cup registers tracks contributed by 222Rn only, while that in the filter cup records tracks due to 222Rn

**Figure 3.** *Twin cups dosimeter.*

and 220Rn. The third SSNTDs film exposed in the bare mode registers alpha tracks contributed by the concentrations of both the gases and their alpha emitting progenies. The dosimeters were kept at a height of 1.5 m from the ceiling of the room and care was taken to keep the bare card at least 10 cm minimum away from any surface. This ensured that errors due to tracks from deposited activity from nearby surfaces were avoided, since the ranges of alpha particles from 222Rn/220Rn are about 10 cm. The global track density rates, due to α-particles emitted by radon, registered on the SSNTDs can write mathematical [11]:

$$
\rho\_S = K\_{\rm RS} \, T \, \mathbf{C}\_{\rm Rn} \tag{53}
$$

on the ventilation rate, therefore *F* was determined by SSNTD based on using can and bare method. In this method, two similar detectors were exposed to radon, one in can-mode configuration (in can detector) and the other in bare-mode configuration (bare detector). *F* can be found as a function of the track density ratio ρB/ρ<sup>S</sup> between bare (*ρB*) and in can (*ρS*) detector, respectively. There are three steps for

1.The potential alpha energy concentration of any mixture of (short-live) radon

3.The ventilation rate as a function of the track density ratio between bare mode

The potential alpha energy concentration (*PAEC*) of any mixture of (short-live)

. This unit is related to the SI units J and m<sup>3</sup> according to 1 J � <sup>m</sup>�<sup>3</sup> = 6.24 �

*PAECTotal* ¼ *PAEC*1*N*<sup>1</sup> þ *PAEC*2*N*<sup>2</sup> þ *PAEC*3*N*<sup>3</sup> þ *PAEC*4*N*<sup>4</sup> (57)

radon or thoron daughters in air is the sum of the potential alpha energy of all daughters atoms present per unit volume of air. The usual unit for this quantity is

where *PAECTotal*, is the total potential alpha energy concentration of any mixture of (short -live) radon daughters in air. *PAECi* (i = 1, 4) are the potential alpha energy for 218Po, 214Pb, 214Bi and 214Po, respectively. Ni is the number atoms of daughters of radon. The concentration potential alpha energy is

*CPAET* <sup>¼</sup> *PAET*

*<sup>V</sup>* <sup>¼</sup> *<sup>λ</sup>iNi*

*f* <sup>2</sup> þ

*PAE*<sup>3</sup> *λ*3

, is the activity concentration fraction. A special unit for this quantity

used for radiation protection purposes is the working level (*WL*). A *WL* is defined as corresponding approximately to the potential alpha energy concentration of short-live radon daughters in air which are in radioactive equilibrium with a radon

*<sup>C</sup>*<sup>1</sup> <sup>¼</sup> *<sup>C</sup>*<sup>2</sup> <sup>¼</sup> *<sup>C</sup>*<sup>3</sup> <sup>¼</sup> *<sup>C</sup>*<sup>4</sup> <sup>¼</sup> *<sup>C</sup>*<sup>0</sup> <sup>¼</sup> *CRn* <sup>¼</sup> <sup>3</sup>*:*7 kBq*:*m�<sup>3</sup> <sup>¼</sup> <sup>3</sup>*:*7*Bq* � *<sup>l</sup>*

*f* <sup>3</sup> þ

*<sup>C</sup>*<sup>0</sup> (60)

*PAE*<sup>4</sup> *λ*4

*Ci* <sup>¼</sup> *Ai*

*PAE*<sup>2</sup> *λ*2

*<sup>V</sup>* (58)

*<sup>V</sup>* (59)

*f* 4

ð61Þ

�<sup>1</sup> (62)

4.The equilibrium factor as a function of the ventilation rate.

�<sup>1</sup> [12]. To express mathematically, we let:

calculating the equilibrium factor [1, 11, 13]:

*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

From Eqs. (57), (58) and (59), we get:

*CPAET* <sup>¼</sup> *PAE*<sup>1</sup>

concentration of 3.7 kBq � <sup>m</sup>�<sup>3</sup> [12].

Eq. (60) become as:

*λ*1

*f* <sup>1</sup> þ

or thoron daughters in air.

2.The working level (*WL*).

and can mode.

MeV � l

<sup>10</sup><sup>9</sup> Mev � <sup>l</sup>

defined as:

where *fi*

**83**

�1

$$
\rho\_F = K\_{RF} \ T \ C\_{Rn} + K\_{TF} \ T \ C\_{Th} \tag{54}
$$

The general solution for this are:

$$\mathbf{C}\_{Rn} = \frac{\rho\_{\rm S}}{K\_{\rm RS}T} \tag{55}$$

$$\mathbf{C}\_{Th} = \frac{\rho\_{\rm S}}{K\_{TF}T} \left(\frac{\rho\_{\rm F}}{\rho\_{\rm S}} - \frac{\mathbf{K}\_{RF}}{\mathbf{K}\_{RS}}\right) \tag{56}$$

where:

*ρ<sup>S</sup>* = Tracks density for sponge cup. *ρ<sup>F</sup>* = Tracks density for filter piper cup. *KRS* =Calibration factor of radon for sponge cup. *KRF* = Calibration factor of radon for filter piper cup. *KTF* = Calibration factor of thoron for filter piper cup. Since, *CTh* is positive quantity, *<sup>ρ</sup><sup>F</sup> ρS* track density ratio should be *<sup>ρ</sup><sup>F</sup> ρS* > *KRF KRS:*

#### **4. Equilibrium factor**

The equilibrium factor (*F*) is defined as the ratio of potential alpha energy concentration (*PAEC*) of actual air-radon mixture (also radon progeny) to the PAEC in secular equilibrium with radon. The equilibrium factor (*F*) is an important parameter in the determination of radon equivalent dose. A common practice for radon hazard assessment nowadays is to, first, determine the radon gas concentration and then to apply an assumed *F* with a typical value of about 0.4 [12]. However, in reality, *F* varies significantly with time and place, and an assumed *F* cannot reflect the actual conditions. Actually, the radon concentration was very dependent

#### *Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

on the ventilation rate, therefore *F* was determined by SSNTD based on using can and bare method. In this method, two similar detectors were exposed to radon, one in can-mode configuration (in can detector) and the other in bare-mode configuration (bare detector). *F* can be found as a function of the track density ratio ρB/ρ<sup>S</sup> between bare (*ρB*) and in can (*ρS*) detector, respectively. There are three steps for calculating the equilibrium factor [1, 11, 13]:


and 220Rn. The third SSNTDs film exposed in the bare mode registers alpha tracks contributed by the concentrations of both the gases and their alpha emitting progenies. The dosimeters were kept at a height of 1.5 m from the ceiling of the room and care was taken to keep the bare card at least 10 cm minimum away from any surface. This ensured that errors due to tracks from deposited activity from nearby surfaces were avoided, since the ranges of alpha particles from 222Rn/220Rn are about 10 cm. The global track density rates, due to α-particles emitted by radon,

*CRn* <sup>¼</sup> *<sup>ρ</sup><sup>S</sup>*

*ρF ρS*

� *KRF KRS* 

track density ratio should be *<sup>ρ</sup><sup>F</sup>*

*KTFT*

*CTh* <sup>¼</sup> *<sup>ρ</sup><sup>S</sup>*

*ρS*

The equilibrium factor (*F*) is defined as the ratio of potential alpha energy concentration (*PAEC*) of actual air-radon mixture (also radon progeny) to the PAEC in secular equilibrium with radon. The equilibrium factor (*F*) is an important parameter in the determination of radon equivalent dose. A common practice for radon hazard assessment nowadays is to, first, determine the radon gas concentration and then to apply an assumed *F* with a typical value of about 0.4 [12]. However, in reality, *F* varies significantly with time and place, and an assumed *F* cannot reflect the actual conditions. Actually, the radon concentration was very dependent

*ρ<sup>S</sup>* ¼ *KRS T CRn* (53)

*KRST* (55)

*ρS* > *KRF KRS:* (56)

*ρ<sup>F</sup>* ¼ *KRF T CRn* þ *KTF T CTh* (54)

registered on the SSNTDs can write mathematical [11]:

*Recent Techniques and Applications in Ionizing Radiation Research*

The general solution for this are:

*ρ<sup>S</sup>* = Tracks density for sponge cup. *ρ<sup>F</sup>* = Tracks density for filter piper cup.

Since, *CTh* is positive quantity, *<sup>ρ</sup><sup>F</sup>*

**4. Equilibrium factor**

*KRS* =Calibration factor of radon for sponge cup. *KRF* = Calibration factor of radon for filter piper cup. *KTF* = Calibration factor of thoron for filter piper cup.

where:

**82**

**Figure 3.**

*Twin cups dosimeter.*


The potential alpha energy concentration (*PAEC*) of any mixture of (short-live) radon or thoron daughters in air is the sum of the potential alpha energy of all daughters atoms present per unit volume of air. The usual unit for this quantity is MeV � l �1 . This unit is related to the SI units J and m<sup>3</sup> according to 1 J � <sup>m</sup>�<sup>3</sup> = 6.24 � <sup>10</sup><sup>9</sup> Mev � <sup>l</sup> �<sup>1</sup> [12]. To express mathematically, we let:

$$PAEC\_{Total} = PAEC\_1N\_1 + PAEC\_2N\_2 + PAEC\_3N\_3 + PAEC\_4N\_4 \tag{57}$$

where *PAECTotal*, is the total potential alpha energy concentration of any mixture of (short -live) radon daughters in air. *PAECi* (i = 1, 4) are the potential alpha energy for 218Po, 214Pb, 214Bi and 214Po, respectively. Ni is the number atoms of daughters of radon. The concentration potential alpha energy is defined as:

$$\mathbf{C}\_{PAET} = \frac{\mathbf{PAET}}{V} \tag{58}$$

$$\mathbf{C}\_{i} = \frac{\mathbf{A}\_{i}}{V} = \frac{\lambda\_{i} N\_{i}}{V} \tag{59}$$

From Eqs. (57), (58) and (59), we get:

$$\mathbf{C}\_{PAET} = \left[\frac{\text{PAE}\_1}{\lambda\_1}f\_1 + \frac{\text{PAE}\_2}{\lambda\_2}f\_2 + \frac{\text{PAE}\_3}{\lambda\_3}f\_3 + \frac{\text{PAE}\_4}{\lambda\_4}f\_4\right] \mathbf{C}\_0 \tag{60}$$

$$\begin{aligned} f\_l &= \frac{C\_l}{C\_0} \\ C\_0 &= C\_{\mathcal{R}n} \end{aligned} \tag{61}$$

where *fi* , is the activity concentration fraction. A special unit for this quantity used for radiation protection purposes is the working level (*WL*). A *WL* is defined as corresponding approximately to the potential alpha energy concentration of short-live radon daughters in air which are in radioactive equilibrium with a radon concentration of 3.7 kBq � <sup>m</sup>�<sup>3</sup> [12].

$$\mathbf{C}\_1 = \mathbf{C}\_2 = \mathbf{C}\_3 = \mathbf{C}\_4 = \mathbf{C}\_0 = \mathbf{C}\_{\text{Rt}} = \mathbf{3.7} \text{ kBq.} \text{m}^{-3} = \mathbf{3.7} \text{Bq} \cdot \text{l}^{-1} \tag{62}$$

Eq. (60) become as:

$$\mathbf{C\_{PAECT}} = \mathbf{W}\mathbf{L} = \frac{\mathbf{3.7}\,\text{PE}\_1}{\lambda\_1} + \frac{\mathbf{3.7}\,\text{PE}\_2}{\lambda\_2} + \frac{\mathbf{3.7}\,\text{PE}\_3}{\lambda\_3} + \frac{\mathbf{3.7}\,\text{PE}\_4}{\lambda\_4} = \mathbf{1.3} \ast \mathbf{10^5}\,\text{MeV}\,\text{l}^{-1} \tag{63}$$

The numerical calculations of Eq. (63) are shown in **Table 3**.

One (*WL*) equal to 1.3 � 105 Mev � <sup>l</sup> �<sup>1</sup> of air. To obtain the concentration potential alpha energy by fraction energy, Eq. (63) multi and divide by 3.7 Bq � l �1 and multi and divide by 1.3 � <sup>10</sup><sup>5</sup> Mev � <sup>l</sup> �1 :

$$C\_{PET} = \left[\frac{\frac{3.7PE\_1}{\lambda\_1}}{1.3 \ast 10^5} f\_1 + \frac{\frac{3.7PE\_2}{\lambda\_2}}{1.3 \ast 10^5} f\_2 + \frac{\frac{3.7PE\_3}{\lambda\_3}}{1.3 \ast 10^5} f\_3 + \frac{\frac{3.7PE\_4}{\lambda\_4}}{1.3 \ast 10^5} f\_4\right] \frac{1.3 \ast 10^5}{3.7} C\_{Ru} \tag{64}$$

$$\mathbf{C\_{PET}} = \left[ \mathbf{0.11} \, f\_1 + \mathbf{0.51} \, f\_2 + \mathbf{0.38} \, f\_3 \right] \frac{\mathbf{1.3} \ast \mathbf{10^5}}{\mathbf{3.7}} \mathbf{C\_{Rn}} \tag{65}$$

To obtain the concentration potential alpha energy by unit *WL* is:

$$C\_{PET}(\text{WL}) = \frac{F\_{Rn} \ C\_{Rn} \left( Bq \ l^{-1} \right)}{3.7} \tag{66}$$

or

$$C\_{PET}(m\text{WL}) = \frac{F\_{Rn}C\_{Rn}\,\,(Bq\,\,m^{-3})}{3.7} \tag{67}$$

where

$$F\_{Rn} = 0.11f\_1 + 0.51f\_2 + 0.38f\_3 \tag{68}$$

*FRn* and *FTn* are the equilibrium factor for radon and thoron, respectively. The maximum value of equilibrium factor is *F* = 1, when the radon or thoron progeny are present in complete equilibrium with radon/thoron that is present. The minimum value of equilibrium factor is *F* = 0, that is mean no-equilibrium between the radon or thoron and its progeny. In our work, we measured the equilibrium factor depending on the ventilation rate. Ventilation rate is one of the parameters used to describe the perturbation caused in radioactive equilibrium of radon/thoron and its descendants in air. Decay of radon and production of radon can be described by the

The first term on the right is the rate of formation of the ith-member of the progeny by radioactive decay of the (i-1)th-member, with constant *<sup>λ</sup><sup>i</sup>*�1; the second term describes the radioactive leakage rate, owing to ventilation *V*, to aerosol grains *Ai* and deposition on the walls *Wi* to which it added the rate of radioactive decay of the ith-member of the progeny, *λi*. The index i, running from 1 to 4, labels the relevant daughter in the radon family: 218Po, 214Pb, 214Bi, 214Po. 222Rn itself will be label with i = 0. For thoron family: 216Po, 212Pb, 212Bi, 212Po. 220Rn (Tn) itself will be labeled with i = 0. Ventilation rate affects equally all members of the family. When

steady state is reached, radon daughter's activities Eq. (71) become as [13]:

*dt* <sup>¼</sup> *<sup>λ</sup><sup>i</sup>*�<sup>1</sup>*Ni*�<sup>1</sup> � <sup>Λ</sup>*iNi* ð Þ <sup>i</sup> <sup>¼</sup> <sup>1</sup> … <sup>4</sup> (71)

Λ*<sup>i</sup>* ¼ *V* þ *Ai* þ *Wi* þ *λ<sup>i</sup>* (72)

*λ<sup>i</sup>*�<sup>1</sup>*Ni*�<sup>1</sup> ¼ Λ*iNi* (73)

rate equations for serial radioactive decay chain (Batman equations):

*dNi*

where

**85**

**Daughters of thoron**

**Table 4.**

**Table 5.**

**Daughters of thoron**

**α-energy (Mev)**

*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

> **α-energy (Mev)**

*Numerical calculations of Eq. (63) for thoron.*

**Half-life (s)**

**Half-life (s)**

Pb-212 zero 38,304 7.8152 4.32E+05 Bi-212 6.1 3636 7.8152 4.10E+04 Po-212 8.78 3.04E-07 8.78 3.85E-06

**Ultimate alpha energy (Mev)**

**Ultimate alpha energy (Mev)**

Po-216 6.78 0.15 14.5952 3.16E+00 0.275

*Numerical calculations of thoron concentration as corresponding to the total energy 1.3* � *<sup>10</sup><sup>5</sup> Mev* � *<sup>l</sup>*

Po-216 6.78 0.15 14.5952 8.69E-01 zero Pb-212 zero 38,304 7.8152 1.19E+05 0.91 Bi-212 6.1 3636 7.8152 1.13E+04 0.09 Po-212 8.78 3.04E-07 8.78 1.06E-06 zero

**Total energy (Mev)**

4.73E+05

**Total energy (Mev)**

1.3E+05

**CTn (Bq** � **l** �**1 )**

> �*1 .*

**Fraction energy**

For Thoron daughters we find the concentration of thoron which give potential energy of alpha its daughters equal to 1.3 � <sup>10</sup><sup>5</sup> Mev � <sup>l</sup> �<sup>1</sup> is 0.275 Bq � <sup>l</sup> �1 , as shown in **Table 4**.

By the same setup, we drive Eq. (60) for thoron and numerical calculations of it, as shown in **Table 5**.

The concentration potential alpha energy for thoron by unit *WL* is:

$$\mathcal{C}\_{\rm PET}(m\mathcal{W}\mathcal{L}) = \frac{F\_{\rm Tn}\mathcal{C}\_{\rm Tn}(Bq.m^{-3})}{0.275} \tag{69}$$

where

$$F\_{\rm Th} = 0.91f\_2 + 0.09f\_3 \tag{70}$$


**Table 3.** *Numerical calculations of Eq. (63).*


*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

**Table 4.**

*CPAECT* <sup>¼</sup> *WL* <sup>¼</sup> <sup>3</sup>*:*<sup>7</sup> *PE*<sup>1</sup>

*CPET* ¼

or

where

in **Table 4**.

where

**Daughters of radon**

**Table 3.**

**84**

*Numerical calculations of Eq. (63).*

as shown in **Table 5**.

*λ*1

One (*WL*) equal to 1.3 � 105 Mev � <sup>l</sup>

and multi and divide by 1.3 � <sup>10</sup><sup>5</sup> Mev � <sup>l</sup>

3*:*7*PE*<sup>1</sup> *λ*1 <sup>1</sup>*:*<sup>3</sup> <sup>∗</sup> <sup>10</sup><sup>5</sup> *<sup>f</sup>* <sup>1</sup> <sup>þ</sup>

þ

*Recent Techniques and Applications in Ionizing Radiation Research*

3*:*7 *PE*<sup>2</sup> *λ*2

3*:*7*PE*<sup>2</sup> *λ*2 <sup>1</sup>*:*<sup>3</sup> <sup>∗</sup> <sup>10</sup><sup>5</sup> *<sup>f</sup>* <sup>2</sup> <sup>þ</sup>

*CPET* ¼ 0*:*11 *f* <sup>1</sup> þ 0*:*51 *f* <sup>2</sup> þ 0*:*38 *f* <sup>3</sup>

To obtain the concentration potential alpha energy by unit *WL* is:

*CPET*ð Þ¼ *WL*

*CPET*ð Þ¼ *mWL*

energy of alpha its daughters equal to 1.3 � <sup>10</sup><sup>5</sup> Mev � <sup>l</sup>

**α-energy (Mev)**

The numerical calculations of Eq. (63) are shown in **Table 3**.

þ

3*:*7 *PE*<sup>3</sup> *λ*3

potential alpha energy by fraction energy, Eq. (63) multi and divide by 3.7 Bq � l

" #

�1 :

3*:*7*PE*<sup>3</sup> *λ*3 <sup>1</sup>*:*<sup>3</sup> <sup>∗</sup> <sup>10</sup><sup>5</sup> *<sup>f</sup>* <sup>3</sup> <sup>þ</sup>

� � <sup>1</sup>*:*<sup>3</sup> <sup>∗</sup> <sup>10</sup><sup>5</sup>

For Thoron daughters we find the concentration of thoron which give potential

By the same setup, we drive Eq. (60) for thoron and numerical calculations of it,

*CPET*ð Þ¼ *mWL FTnCTn Bq:m*�<sup>3</sup> ð Þ

Po-218 6 183 6 + 7.69 1.34E+04 0.11 Pb-214 zero 1563 zero+7.68 6.41E+04 0.51 Bi-214 zero 1182 zero +7.68 4.85E+04 0.38 Po-214 7.69 1.64E-04 7.68 6.72E-03 zero

**Ultimate alpha energy (Mev)**

The concentration potential alpha energy for thoron by unit *WL* is:

**Half-life (s)**

*FRn CRn Bq l*�<sup>1</sup> � �

*FRnCRn Bq m*�<sup>3</sup> ð Þ

*FRn* ¼ 0*:*11 *f* <sup>1</sup> þ 0*:*51 *f* <sup>2</sup> þ 0*:*38 *f* <sup>3</sup> (68)

*FTn* ¼ 0*:*91 *f* <sup>2</sup> þ 0*:*09 *f* <sup>3</sup> (70)

*CPAECT* ¼ 1.3E+05

þ

3*:*7 *PE*<sup>4</sup> *λ*4

�<sup>1</sup> of air. To obtain the concentration

3*:*7*PE*<sup>4</sup> *λ*4 <sup>1</sup>*:*<sup>3</sup> <sup>∗</sup> <sup>10</sup><sup>5</sup> *<sup>f</sup>* <sup>4</sup>

3*:*7

<sup>3</sup>*:*<sup>7</sup> (66)

<sup>3</sup>*:*<sup>7</sup> (67)

�<sup>1</sup> is 0.275 Bq � <sup>l</sup>

<sup>0</sup>*:*<sup>275</sup> (69)

**Total energy (Mev)**

�1

, as shown

**Fraction energy**

<sup>¼</sup> <sup>1</sup>*:*<sup>3</sup> <sup>∗</sup> 105 *Mev l*�<sup>1</sup> (63)

1*:*3 ∗ 10<sup>5</sup> 3*:*7

*CRn* (65)

�1

*CRn*

(64)

*Numerical calculations of thoron concentration as corresponding to the total energy 1.3* � *<sup>10</sup><sup>5</sup> Mev* � *<sup>l</sup>* �*1 .*


#### **Table 5.**

*Numerical calculations of Eq. (63) for thoron.*

*FRn* and *FTn* are the equilibrium factor for radon and thoron, respectively. The maximum value of equilibrium factor is *F* = 1, when the radon or thoron progeny are present in complete equilibrium with radon/thoron that is present. The minimum value of equilibrium factor is *F* = 0, that is mean no-equilibrium between the radon or thoron and its progeny. In our work, we measured the equilibrium factor depending on the ventilation rate. Ventilation rate is one of the parameters used to describe the perturbation caused in radioactive equilibrium of radon/thoron and its descendants in air. Decay of radon and production of radon can be described by the rate equations for serial radioactive decay chain (Batman equations):

$$\frac{d\mathbf{N}\_i}{dt} = \lambda\_{i-1}\mathbf{N}\_{i-1} - \Lambda\_i\mathbf{N}\_i \text{ (i = 1 \dots 4)}\tag{71}$$

where

$$
\Lambda\_i = V + A\_i + W\_i + \lambda\_i \tag{72}
$$

The first term on the right is the rate of formation of the ith-member of the progeny by radioactive decay of the (i-1)th-member, with constant *<sup>λ</sup><sup>i</sup>*�1; the second term describes the radioactive leakage rate, owing to ventilation *V*, to aerosol grains *Ai* and deposition on the walls *Wi* to which it added the rate of radioactive decay of the ith-member of the progeny, *λi*. The index i, running from 1 to 4, labels the relevant daughter in the radon family: 218Po, 214Pb, 214Bi, 214Po. 222Rn itself will be label with i = 0. For thoron family: 216Po, 212Pb, 212Bi, 212Po. 220Rn (Tn) itself will be labeled with i = 0. Ventilation rate affects equally all members of the family. When steady state is reached, radon daughter's activities Eq. (71) become as [13]:

$$
\lambda\_{i-1} \mathbf{N}\_{i-1} = \Lambda\_i \mathbf{N}\_i \tag{73}
$$

*Recent Techniques and Applications in Ionizing Radiation Research*

or

$$\frac{C\_i}{C\_{i-1}} = \frac{\lambda\_i}{\Lambda\_i} = d\_i \tag{74}$$

ð86Þ

ð89Þ

From Eqs. (74), (75), (76) and (84), we obtain:

ð Þ *<sup>λ</sup>*<sup>1</sup> <sup>þ</sup> *<sup>V</sup>* <sup>0</sup>*:*<sup>11</sup> <sup>þ</sup> <sup>0</sup>*:*<sup>51</sup> *<sup>λ</sup>*<sup>2</sup>

*FTn* <sup>¼</sup> *<sup>λ</sup>*1*λ*<sup>2</sup>

*λ*1 ð Þ *λ*<sup>1</sup> þ *V*

*λ*2 ð Þ *λ*<sup>2</sup> þ *V*

Ventilation rate is the solution of Eq. (89), obtainable by means of standard algebraic procedures. The equilibrium factor is strongly dependent on the ventilation rate. This dependence was expressed by using Eqs. (68), (70), (75) and (76).

ð Þ *<sup>λ</sup>*<sup>1</sup> <sup>þ</sup> *<sup>V</sup>* ð Þ *<sup>λ</sup>*<sup>2</sup> <sup>þ</sup> *<sup>V</sup>* <sup>0</sup>*:*<sup>91</sup> <sup>þ</sup> <sup>0</sup>*:*<sup>09</sup> *<sup>λ</sup>*<sup>3</sup>

Values of the equilibrium factor *F*, follow from solution of Eq. (88) and

**5. Determination of the radon diffusion coefficient in porous medium**

The diffusion of radon is a process determined by radon gas concentration gradient across the radon gas sources (rocks, soils, building materials, and other different materials) and the surrounding air. The knowledge of radon diffusion coefficient makes it possible to determine other features of a material related to radon. The diffusion of radon through the porous medium can be described by Fick's second laws [1, 14, 15]. The basic concept in measuring radon concentration involves observations of radon diffusion through the porous medium being studied. This medium separates two chambers that have different radon concentrations. In such configurations, radon diffusion comes from one chamber to another, primarily in one direction only. The standard method for the measurement of radon diffusion coefficient beads on the evaluation of radon flux through tested material exposed to high radon concentration and placed between two containers by measuring in both sides of material. For this, one of the containers is connected to radon source (radium source) and the other where the radon concentration is periodically evaluated as shown in **Figure 4**. It is assumed that radon is well mixed in both containers.

ð Þ *<sup>λ</sup>*<sup>2</sup> <sup>þ</sup> *<sup>V</sup>* <sup>þ</sup> <sup>0</sup>*:*<sup>38</sup> *<sup>λ</sup>*2*λ*<sup>3</sup>

(90)

ð Þ *λ*<sup>2</sup> þ *V* ð Þ *λ*<sup>3</sup> þ *V*

ð Þ *λ*<sup>3</sup> þ *V* (91)

*λ*3

*<sup>V</sup>*<sup>3</sup> <sup>þ</sup> *<sup>a</sup>*2*V*<sup>2</sup> <sup>þ</sup> *<sup>a</sup>*<sup>1</sup> *<sup>V</sup>* <sup>þ</sup> *<sup>a</sup>*<sup>0</sup> <sup>¼</sup> <sup>0</sup> (88)

ð Þ *<sup>λ</sup>*<sup>3</sup> <sup>þ</sup> *<sup>V</sup>* <sup>¼</sup> *KSBρBS* � 1 (87)

*λ*1 ð Þ *<sup>λ</sup>*<sup>1</sup> <sup>þ</sup> *<sup>V</sup>* <sup>þ</sup>

*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

After some setup, we obtain:

where

*FRn* <sup>¼</sup> *<sup>λ</sup>*<sup>1</sup>

**87**

combined Eq. (90) and Eq. (91).

From Eq. (74), we obtain:

$$\begin{aligned} f\_1 &= \frac{c\_1}{c\_0} = d\_1\\ f\_2 &= \frac{C\_2}{C\_0} = d\_1 d\_2\\ f\_3 &= \frac{C\_3}{C\_0} = d\_1 d\_2 d\_3\\ f\_4 &= \frac{c\_4}{c\_0} = d\_1 d\_2 d\_3 \end{aligned} \tag{75}$$

where *<sup>C</sup>*<sup>4</sup> *<sup>C</sup>*<sup>3</sup> ¼ *d*<sup>4</sup> ¼ 1 since *C*<sup>3</sup> ¼ *C*4For *λ*<sup>3</sup> ≪ *λ*<sup>4</sup>

When the ventilation rate is the only environmental affecting disequilibrium or when it is the dominant on, ventilation rates and the equilibrium factor are obtained by track density measurements, so:

$$
\Lambda\_i = V + \lambda\_i \tag{76}
$$

The track density of both bare mode and can mode (with sponge filter) detector relates the concentration of radon and its daughters as:

In can mode:

$$
\rho\_{\mathbb{S}} = \rho\_0 + \rho\_1 + \rho\_4 \tag{77}
$$

$$
\rho\_S = K\_0 C\_0 T + K\_1 C\_1 T + K\_4 C\_4 T \tag{78}
$$

$$
\rho\_S = \left(K\_0 + K\_1 f\_1 + K\_4 f\_4\right) \mathbf{C}\_0 T \tag{79}
$$

In can mode *f* <sup>1</sup> ¼ *f* <sup>2</sup> ¼ *f* <sup>3</sup> ¼ *f* <sup>4</sup> ¼ 1, Eq. (79) become as:

$$
\rho\_S = K\_S C\_0 T \tag{80}
$$

where

$$K\_t = K\_0 + K\_1 + K\_4 \tag{81}$$

In bare mode (in absence thoron)

$$
\rho\_B = \rho\_0 + \rho\_1 + \rho\_4 \tag{82}
$$

$$
\rho\_B = (\overline{K}\_0 + \overline{K}\_1 f\_1 + \overline{K}\_4 f\_4) \overline{C}\_0 T \tag{83}
$$

In bare mode *f* <sup>1</sup> 6¼ *f* <sup>2</sup> 6¼ *f* <sup>3</sup> 6¼ *f* <sup>4</sup> because no equilibrium between the radon and its progenies, but *K*<sup>0</sup> ¼ *K*<sup>1</sup> ¼ *K*<sup>4</sup> ¼ *KB*, therefore Eq. (83) become as:

$$
\rho\_B = K\_B (1 + f\_1 + f\_4) \overline{\mathbf{C}}\_0 T \tag{84}
$$

By dividing Eq. (84) on Eq. (80) when *C*<sup>0</sup> ¼ *C*0, we obtain:

$$\mathbf{1} + f\_1 + f\_4 = K\_{\text{SB}} \rho\_{\text{BS}} \tag{85}$$

*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

$$\begin{aligned} \rho\_{BS} &= \frac{\rho\_B}{\rho\_S} \\ \mathbf{K}\_{SB} &= \frac{K\_S}{\kappa\_B} \end{aligned} \qquad\tag{86}$$

From Eqs. (74), (75), (76) and (84), we obtain:

$$\frac{\lambda\_1}{\left(\lambda\_1 + V\right)} + \frac{\lambda\_1}{\left(\lambda\_1 + V\right)} \frac{\lambda\_2}{\left(\lambda\_2 + V\right)} \frac{\lambda\_3}{\left(\lambda\_3 + V\right)} = K\_{SB} \rho\_{BS} - 1 \tag{87}$$

After some setup, we obtain:

$$V^3 + a\_2V^2 + a\_1\ V + a\_0 = 0\tag{88}$$

where

or

where *<sup>C</sup>*<sup>4</sup>

In can mode:

where

**86**

From Eq. (74), we obtain:

by track density measurements, so:

In bare mode (in absence thoron)

*Ci Ci*�<sup>1</sup>

*<sup>C</sup>*<sup>3</sup> ¼ *d*<sup>4</sup> ¼ 1 since *C*<sup>3</sup> ¼ *C*4For *λ*<sup>3</sup> ≪ *λ*<sup>4</sup>

*Recent Techniques and Applications in Ionizing Radiation Research*

relates the concentration of radon and its daughters as:

¼ *λi* Λ*i*

When the ventilation rate is the only environmental affecting disequilibrium or when it is the dominant on, ventilation rates and the equilibrium factor are obtained

The track density of both bare mode and can mode (with sponge filter) detector

*ρ<sup>S</sup>* ¼ *K*<sup>0</sup> þ *K*<sup>1</sup> *f* <sup>1</sup> þ *K*<sup>4</sup> *f* <sup>4</sup>

*ρ<sup>B</sup>* ¼ *K*<sup>0</sup> þ *K*<sup>1</sup> *f* <sup>1</sup> þ *K*<sup>4</sup> *f* <sup>4</sup>

*ρ<sup>B</sup>* ¼ *KB* 1 þ *f* <sup>1</sup> þ *f* <sup>4</sup>

its progenies, but *K*<sup>0</sup> ¼ *K*<sup>1</sup> ¼ *K*<sup>4</sup> ¼ *KB*, therefore Eq. (83) become as:

By dividing Eq. (84) on Eq. (80) when *C*<sup>0</sup> ¼ *C*0, we obtain:

In bare mode *f* <sup>1</sup> 6¼ *f* <sup>2</sup> 6¼ *f* <sup>3</sup> 6¼ *f* <sup>4</sup> because no equilibrium between the radon and

In can mode *f* <sup>1</sup> ¼ *f* <sup>2</sup> ¼ *f* <sup>3</sup> ¼ *f* <sup>4</sup> ¼ 1, Eq. (79) become as:

¼ *di* (74)

Λ*<sup>i</sup>* ¼ *V* þ *λ<sup>i</sup>* (76)

*ρ<sup>S</sup>* ¼ *ρ*<sup>0</sup> þ *ρ*<sup>1</sup> þ *ρ*<sup>4</sup> (77)

*C*0*T* (79)

*ρ<sup>S</sup>* ¼ *KSC*0*T* (80)

*Ks* ¼ *K*<sup>0</sup> þ *K*<sup>1</sup> þ *K*<sup>4</sup> (81)

*ρ<sup>B</sup>* ¼ *ρ*<sup>0</sup> þ *ρ*<sup>1</sup> þ *ρ*<sup>4</sup> (82)

*C*0*T* (83)

*C*0*T* (84)

1 þ *f* <sup>1</sup> þ *f* <sup>4</sup> ¼ *KSBρBS* (85)

*ρ<sup>S</sup>* ¼ *K*0*C*0*T* þ *K*1*C*1*T* þ *K*4*C*4*T* (78)

ð75Þ

$$\begin{array}{l} a\_2 = (1+\mathcal{B})\lambda\_1 + \lambda\_2 + \lambda\_3\\ a\_1 = (1+\mathcal{B})(\lambda\_2 + \lambda\_3)\lambda\_1 + \lambda\_2\lambda\_3\\ a\_0 = (1+2\mathcal{B})\lambda\_1\lambda\_2\lambda\_3\\ \mathcal{B} = \frac{1}{1 - K\_{SB}\rho\_{BS}} \end{array} \tag{89}$$

Ventilation rate is the solution of Eq. (89), obtainable by means of standard algebraic procedures. The equilibrium factor is strongly dependent on the ventilation rate. This dependence was expressed by using Eqs. (68), (70), (75) and (76).

$$F\_{R\pi} = \frac{\lambda\_1}{(\lambda\_1 + V)} \left( 0.11 + 0.51 \frac{\lambda\_2}{(\lambda\_2 + V)} + 0.38 \frac{\lambda\_2 \lambda\_3}{(\lambda\_2 + V)(\lambda\_3 + V)} \right) \tag{90}$$

$$F\_{\rm T\pi} = \frac{\lambda\_1 \lambda\_2}{(\lambda\_1 + V)(\lambda\_2 + V)} \left( 0.91 + 0.09 \,\frac{\lambda\_3}{(\lambda\_3 + V)} \right) \tag{91}$$

Values of the equilibrium factor *F*, follow from solution of Eq. (88) and combined Eq. (90) and Eq. (91).

#### **5. Determination of the radon diffusion coefficient in porous medium**

The diffusion of radon is a process determined by radon gas concentration gradient across the radon gas sources (rocks, soils, building materials, and other different materials) and the surrounding air. The knowledge of radon diffusion coefficient makes it possible to determine other features of a material related to radon. The diffusion of radon through the porous medium can be described by Fick's second laws [1, 14, 15]. The basic concept in measuring radon concentration involves observations of radon diffusion through the porous medium being studied. This medium separates two chambers that have different radon concentrations. In such configurations, radon diffusion comes from one chamber to another, primarily in one direction only. The standard method for the measurement of radon diffusion coefficient beads on the evaluation of radon flux through tested material exposed to high radon concentration and placed between two containers by measuring in both sides of material. For this, one of the containers is connected to radon source (radium source) and the other where the radon concentration is periodically evaluated as shown in **Figure 4**. It is assumed that radon is well mixed in both containers.

**Figure 4.** *Diffusion radon chambers.*

The determination of the radon diffusion coefficient with this method is normally performed under steady state conditions.

The container 1 has volume *V1* and radon concentration *C1* and container 2 has volume *V2* and radon concentration *C2*. It is assumed that the material represents thickness d and area A produced P is the radon production rate (Bq � <sup>m</sup>�<sup>3</sup> � <sup>s</sup> �1 ) and has diffusion coefficient *D*. We neglect radon production within the porous material itself and no leakage in containers. Radon transport in porous material is described by a general equation of continuity, which includes four basic processes: generation, decay, diffusion and convection. Under the supposition of the timedependent one-dimensional differential equation (no convection) describing the radon activity concentration C0 is given by Fick' s second law:

$$\frac{\partial \mathcal{C}\_0(\mathbf{z}, t)}{\partial t} = D\_\varepsilon \frac{\partial^2 \mathcal{C}\_0(\mathbf{z}, t)}{\partial \mathbf{z}^2} - \lambda \, \mathcal{C}\_0(\mathbf{z}, t) + P \tag{92}$$

where *<sup>C</sup>*0ð Þ *<sup>z</sup>*, *<sup>t</sup>* is the radon concentration within the pores (Bq/m<sup>3</sup> ), *D* is the bulk diffusion coefficient (m2 /h, gas flux expressed per unit area of material as a whole), *De* is the effective diffusion coefficient *λ* is the radon decay constant, *ε* is the prostiy and *<sup>P</sup>* is the production rate of radon in the pore air (Bq/m<sup>3</sup> � h):

$$D\_{\varepsilon} = \frac{D}{\varepsilon} \tag{93}$$

where *A, B* are integral constant obtained by boundary conditions, *l* is the diffusion length of radon (m). The boundary conditions are formed by, it is

we needed:

where

We get two equations:

*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

By using the relations:

sinh *<sup>d</sup>*�*<sup>z</sup> l* � �

sinh *<sup>d</sup> l* � � *<sup>C</sup>*<sup>1</sup> <sup>þ</sup>

s first law:

*l* � �

*dz* <sup>¼</sup> � cosh *<sup>d</sup>*�*<sup>z</sup>*

*l*sinh *<sup>d</sup> l* � � *<sup>C</sup>*<sup>1</sup> <sup>þ</sup>

*C*0ð Þ¼ *z*

From Fick'

We get:

*dC*0ð Þ*z*

**89**

assumed that the radon concentration at the boundary conditions is specified by the radon concentration of incoming air and the radon concentration is set to a constant value at these boundary conditions. Two boundary conditions at equilibrium rate,

*C*<sup>1</sup> ¼ *A* þ *B* þ

*<sup>C</sup>*<sup>2</sup> <sup>¼</sup> *A e<sup>β</sup>* <sup>þ</sup> *B e*�*<sup>β</sup>* <sup>þ</sup>

*<sup>β</sup>* <sup>¼</sup> *<sup>d</sup>*

1

*<sup>e</sup><sup>β</sup>* � *<sup>e</sup>*�*<sup>β</sup> <sup>C</sup>*<sup>2</sup> <sup>þ</sup>

sinh *<sup>d</sup>*�*<sup>z</sup> l*

*<sup>E</sup>* <sup>¼</sup> *<sup>λ</sup> V C*<sup>2</sup>

*dC*0ð Þ*z dz*

� � � � *z*¼*d*

cosh *<sup>z</sup> α*

*E* ¼ �*De*

cosh *<sup>z</sup> l* � �

*l*sinh *<sup>d</sup> l* � �*C*<sup>2</sup> <sup>þ</sup>

*<sup>e</sup><sup>β</sup>* � *<sup>e</sup>*�*<sup>β</sup> <sup>C</sup>*<sup>2</sup> � <sup>1</sup> � *<sup>e</sup>*�*<sup>β</sup>*

*e<sup>β</sup>* � *e*�*<sup>β</sup>*

<sup>1</sup> � *<sup>e</sup><sup>β</sup> e<sup>β</sup>* � *e*�*<sup>β</sup>*

� � <sup>þ</sup> sinh *<sup>z</sup>*

! *<sup>P</sup>*

sinh *<sup>d</sup> l*

By solving Eqs. (99) and (100) and some mathematical step, we get:

*<sup>A</sup>* <sup>¼</sup> �*e*�*<sup>β</sup>*

*<sup>B</sup>* <sup>¼</sup> *<sup>e</sup><sup>β</sup>*

*<sup>e</sup><sup>β</sup>* � *<sup>e</sup>*�*<sup>β</sup> <sup>C</sup>*<sup>1</sup> <sup>þ</sup>

And mathematical steps, we get the general solution:

sinh *<sup>z</sup> l* � �

sinh *<sup>d</sup> l* � �*C*<sup>2</sup> <sup>þ</sup>

From steady state of exhalation radon Eq. (29), we get:

*<sup>e</sup><sup>β</sup>* � *<sup>e</sup>*�*<sup>β</sup> <sup>C</sup>*<sup>1</sup> � <sup>1</sup>

*P*

*P*

*<sup>λ</sup>* (99)

*<sup>l</sup>* (101)

*P*

*P*

*l* � �

� � � <sup>1</sup>

*<sup>A</sup>* (106)

� � � cosh *<sup>d</sup>*�*<sup>z</sup>*

*l*sinh *<sup>d</sup> l* � � ! *<sup>P</sup>*

*α* � �

*<sup>λ</sup>* (102)

*<sup>λ</sup>* (103)

ð104Þ

*<sup>λ</sup>* (105)

(107)

*<sup>λ</sup>* (108)

*<sup>λ</sup>* (100)

ð98Þ

$$P = \frac{f \text{ } \lambda \text{ C}\_{\text{Ra}} \text{ } \rho \text{ }}{\varepsilon} \tag{94}$$

where, *f* is the emanation fraction, *ρ* is the bulk density (kg/m<sup>3</sup> ) and *CRa* is the radium concentration (Bq/kg).

In steady state *<sup>∂</sup>C*0ð Þ *<sup>z</sup>*, *<sup>t</sup> <sup>∂</sup><sup>t</sup>* ¼ 0 and Eq. (92) becomes:

$$\frac{d^2\mathcal{C}\_0(z)}{dz^2} - \frac{\lambda}{D\_\epsilon}\mathcal{C}\_0(z) + \frac{P}{D\_\epsilon} = \mathbf{0} \tag{95}$$

The general solution is:

$$\mathbf{C}\_{0}(x) = A \, e^{x/l} + B \, e^{-x/l} + \frac{P}{\lambda} \tag{96}$$

$$d = \sqrt{\frac{D\_e}{\lambda}}\tag{97}$$

*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

where *A, B* are integral constant obtained by boundary conditions, *l* is the diffusion length of radon (m). The boundary conditions are formed by, it is assumed that the radon concentration at the boundary conditions is specified by the radon concentration of incoming air and the radon concentration is set to a constant value at these boundary conditions. Two boundary conditions at equilibrium rate, we needed:

$$\begin{cases} \mathcal{C}\_0(\mathbf{z} = 0) = \mathcal{C}\_1 \\ \mathcal{C}\_0(\mathbf{z} = d) = \mathcal{C}\_2 \end{cases} \right\} \tag{98}$$

We get two equations:

$$\mathbf{C}\_1 = \mathbf{A} + \mathbf{B} + \frac{P}{\lambda} \tag{99}$$

$$\mathbf{C}\_2 = \mathbf{A} \,\, \mathbf{e}^{\beta} + \mathbf{B} \,\, \mathbf{e}^{-\beta} + \frac{P}{\lambda} \,\, \tag{100}$$

where

The determination of the radon diffusion coefficient with this method is normally

has diffusion coefficient *D*. We neglect radon production within the porous material itself and no leakage in containers. Radon transport in porous material is described by a general equation of continuity, which includes four basic processes: generation, decay, diffusion and convection. Under the supposition of the timedependent one-dimensional differential equation (no convection) describing the

*C*0ð Þ *z*, *t*

*De* is the effective diffusion coefficient *λ* is the radon decay constant, *ε* is the prostiy

*De* <sup>¼</sup> *<sup>D</sup>*

*<sup>P</sup>* <sup>¼</sup> *<sup>f</sup> <sup>λ</sup> CRa <sup>ρ</sup>*

s second law:

/h, gas flux expressed per unit area of material as a whole),

*<sup>∂</sup>z*<sup>2</sup> � *<sup>λ</sup> <sup>C</sup>*0ð Þþ *<sup>z</sup>*, *<sup>t</sup> <sup>P</sup>* (92)

*<sup>ε</sup>* (93)

*<sup>ε</sup>* (94)

¼ 0 (95)

*<sup>λ</sup>* (96)

The container 1 has volume *V1* and radon concentration *C1* and container 2 has volume *V2* and radon concentration *C2*. It is assumed that the material represents thickness d and area A produced P is the radon production rate (Bq � <sup>m</sup>�<sup>3</sup> � <sup>s</sup>

�1 ) and

), *D* is the bulk

) and *CRa* is the

(97)

performed under steady state conditions.

*Recent Techniques and Applications in Ionizing Radiation Research*

radon activity concentration C0 is given by Fick'

diffusion coefficient (m2

**Figure 4.**

*Diffusion radon chambers.*

radium concentration (Bq/kg). In steady state *<sup>∂</sup>C*0ð Þ *<sup>z</sup>*, *<sup>t</sup>*

The general solution is:

**88**

*<sup>∂</sup>C*0ð Þ *<sup>z</sup>*, *<sup>t</sup>*

*<sup>∂</sup><sup>t</sup>* <sup>¼</sup> *De*

and *<sup>P</sup>* is the production rate of radon in the pore air (Bq/m<sup>3</sup> � h):

*∂*2

where *<sup>C</sup>*0ð Þ *<sup>z</sup>*, *<sup>t</sup>* is the radon concentration within the pores (Bq/m<sup>3</sup>

where, *f* is the emanation fraction, *ρ* is the bulk density (kg/m<sup>3</sup>

*<sup>∂</sup><sup>t</sup>* ¼ 0 and Eq. (92) becomes:

*De*

*<sup>C</sup>*0ð Þ¼ *<sup>z</sup> A e<sup>z</sup>=<sup>l</sup>* <sup>þ</sup> *B e*�*z=<sup>l</sup>* <sup>þ</sup>

*l* ¼

*C*0ð Þþ *z*

ffiffiffiffiffi *De λ* r

*P De*

*P*

*d*2 *C*0ð Þ*z dz*<sup>2</sup> � *<sup>λ</sup>*

$$
\beta = \frac{d}{l} \tag{101}
$$

By solving Eqs. (99) and (100) and some mathematical step, we get:

$$A = \frac{-e^{-\beta}}{e^{\beta} - e^{-\beta}} \mathbf{C}\_1 + \frac{\mathbf{1}}{e^{\beta} - e^{-\beta}} \mathbf{C}\_2 - \frac{\mathbf{1} - e^{-\beta}}{e^{\beta} - e^{-\beta}} \frac{P}{\lambda} \tag{102}$$

$$B = \frac{e^{\beta}}{e^{\beta} - e^{-\beta}} \mathbf{C}\_1 - \frac{\mathbf{1}}{e^{\beta} - e^{-\beta}} \mathbf{C}\_2 + \frac{\mathbf{1} - e^{\beta}}{e^{\beta} - e^{-\beta}} \frac{P}{\lambda} \tag{103}$$

By using the relations:

$$\begin{aligned} e^{\beta} + e^{-\beta} &= 2 \cosh \beta \\ e^{\beta} - e^{-\beta} &= 2 \sinh \beta \end{aligned} \qquad \tag{104}$$

And mathematical steps, we get the general solution:

$$\mathbf{C}\_{0}(\mathbf{z}) = \frac{\sinh\left(\frac{d-\mathbf{z}}{l}\right)}{\sinh\left(\frac{d}{l}\right)} \mathbf{C}\_{1} + \frac{\sinh\left(\frac{\mathbf{z}}{l}\right)}{\sinh\left(\frac{d}{l}\right)} \mathbf{C}\_{2} + \left(\frac{\sinh\left(\frac{d-\mathbf{z}}{l}\right) + \sinh\left(\frac{\mathbf{z}}{l}\right)}{\sinh\left(\frac{d}{l}\right)} - \mathbf{1}\right) \frac{P}{\lambda} \tag{105}$$

From steady state of exhalation radon Eq. (29), we get:

$$E = \frac{\lambda \text{ V C}\_2}{A} \tag{106}$$

From Fick' s first law:

$$E = -D\_\epsilon \frac{dC\_0(z)}{dz}\bigg|\_{z=d} \tag{107}$$

We get:

$$\frac{d\mathbf{C}\_{0}(\mathbf{z})}{dz} = \frac{-\cosh\left(\frac{d-\mathbf{z}}{l}\right)}{l\sinh\left(\frac{d}{l}\right)}\mathbf{C}\_{1} + \frac{\cosh\left(\frac{\mathbf{z}}{l}\right)}{l\sinh\left(\frac{d}{l}\right)}\mathbf{C}\_{2} + \left(\frac{\cosh\left(\frac{\mathbf{z}}{a}\right) - \cosh\left(\frac{d-\mathbf{z}}{a}\right)}{l\sinh\left(\frac{d}{l}\right)}\right)\frac{P}{\lambda} \tag{108}$$

*Recent Techniques and Applications in Ionizing Radiation Research*

$$\left. \frac{d\mathbf{C}\_0(z)}{dz} \right|\_{z=d} = \frac{-\mathbf{1}}{l \sinh\left(\frac{d}{l}\right)} \mathbf{C}\_1 + \frac{\cosh\left(\frac{d}{l}\right)}{l \sinh\left(\frac{d}{l}\right)} \mathbf{C}\_2 + \left(\frac{\cosh\left(\frac{d}{a}\right) - \mathbf{1}}{l \sinh\left(\frac{d}{l}\right)}\right) \frac{P}{\lambda} \tag{109}$$

Substitute Eq. (109) in Eq. (107), we obtain:

$$E = \frac{-D\_\epsilon}{l \sinh\left(\frac{d}{l}\right)} \left\{-\mathbf{C}\_1 + \cosh\left(\frac{d}{l}\right)\mathbf{C}\_2 - \left(\cosh\left(\frac{d}{l}\right) - \mathbf{1}\right)\frac{P}{\lambda}\right\} \tag{110}$$

From Eq. (106) and Eq. (110), we get:

$$C\_2 = \frac{C\_1}{\cosh\left(\frac{d}{l}\right) + \frac{l l V\_2}{D\_l A} \sinh\left(\frac{d}{l}\right)} + \frac{1 - \cosh\left(\frac{d}{l}\right)}{\cosh\left(\frac{d}{l}\right) + \frac{l l V\_2}{D\_l A} \sinh\left(\frac{d}{l}\right)} \frac{P}{\lambda} \tag{111}$$

Since,

$$\begin{cases} V\_2 = A \, h \\ l^2 = \frac{D\_e}{\lambda} \\ \frac{\lambda \nu\_2}{D\_0 A} = \frac{h}{l} \end{cases} \tag{112}$$

sponge. In actual terms it means that the covers are reduced from concentration inter cup to detection [16]. Therefore, we define transmission factor as the ratio between the concentrations inter cup and outside cup. The purpose from calculate diffusion coefficient and transmission factor to get actual radon concentration in air atmosphere. It is assumed that the gas enters the chamber through porous filter by the process of diffusion with diffusion coefficient *D*<sup>1</sup> and *D*<sup>2</sup> in air. If *C1* is the average radon/thoron gas concentration in the cup and *Co* is out the cup. Let the

Then, the steady state equations for described the radon gas diffusion internal porous filter and in air space in cup may be written as Eq. (95), (*P* = 0, because of

*D*1

*D*<sup>2</sup>

where *A1, B1, A2, B2,* are integral constants obtained by boundary conditions, *l*1, *l*<sup>2</sup> are the diffusion length of radon (m), *D1, D2* are diffusion coefficients for

1.The boundary conditions at equilibrium at sides of porous filter are:

*<sup>x</sup>=l*<sup>1</sup> <sup>þ</sup> *<sup>B</sup>*1*<sup>e</sup>*

*<sup>x</sup>=l*<sup>2</sup> <sup>þ</sup> *<sup>B</sup>*2*<sup>e</sup>*

*C*1ð Þ¼ *x* 0 (118)

*C*2ð Þ¼ *x* 0 (119)

�*x=l*<sup>1</sup> (120)

�*x=l*<sup>2</sup> (121)

ð122Þ

ð123Þ

radon diffusion in x-direction **Figure 5** [1, 14, 16].

*d*2 *C*1ð Þ *x dx*<sup>2</sup> � *<sup>λ</sup>*

*d*2 *C*2ð Þ *x dx*<sup>2</sup> � *<sup>λ</sup>*

*C*1ð Þ¼ *x A*1*e*

*C*2ð Þ¼ *x A*2*e*

the lack of a source of radium) respectively:

*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

The general solutions are

**Figure 5.** *Diffusion radon cup.*

porous filter and air respectively.

**91**

The solutions of these equations are:

Substitute set Eq. (112) in Eq. (111), we get:

$$C\_2 = \frac{C\_1}{\cosh\left(\frac{d}{l}\right) + \frac{h}{l}\sinh\left(\frac{d}{l}\right)} + \frac{1 - \cosh\left(\frac{d}{l}\right)}{\cosh\left(\frac{d}{l}\right) + \frac{h}{l}\sinh\left(\frac{d}{l}\right)} \frac{P}{\lambda} \tag{113}$$

Rewrite Eq. (113):

$$\left(1 - \frac{P}{\lambda \, C\_2}\right) \cosh\left(\frac{d}{l}\right) + \frac{h}{l} \sinh\left(\frac{d}{l}\right) - \left(\frac{C\_1}{C\_2} - \frac{P}{\lambda \, C\_2}\right) = 0\tag{114}$$

From Eqs. (101) and (114), we get final relation:

$$\left(\mathbf{1} - \frac{P}{\lambda \,\mathbf{C}\_2}\right) \cosh \beta + \frac{h}{d} \beta \sinh \beta - \left(\frac{\mathbf{C}\_1}{\mathbf{C}\_2} - \frac{P}{\lambda \,\mathbf{C}\_2}\right) = \mathbf{0} \tag{115}$$

Eq. (115) is nonlinear equation; therefore, the radon diffusion coefficient *D* can be numerically calculated by using the Newton-Raphson method.

IF *β* is small, and by using set relation in Eq. (116), we can make approximation to evolution radon diffusion coefficient by simple relation as:

$$\begin{aligned} \sinh \beta &= \frac{\,^{\beta \cdot \beta \cdots \beta} \,^{-\beta}}{\,^{2} \cosh \beta} = \frac{1 + \beta - 1 + \beta}{2} = \beta \\\cosh \beta &= \frac{\,^{\alpha \cdot \beta \cdots \alpha \cdot \beta}}{2} = \frac{1 + \beta + 1 - \beta}{2} = 1 \end{aligned} \tag{116}$$

We find simple relation to calculate the effective diffusion coefficient Eq. (117).

$$D\_{\epsilon} = \frac{\lambda \, d \, h}{\frac{\epsilon}{C\_2} - 1} \tag{117}$$

#### **6. Transmission factor**

The purpose of using covers of cup (sponge or paper filter) to allow entry radon and thoron gases only without its daughters for filter paper and radon only for

*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

**Figure 5.** *Diffusion radon cup.*

*dC*0ð Þ*z dz*

� � � � *z*¼*d*

*<sup>E</sup>* <sup>¼</sup> �*De l* sinh *<sup>d</sup> l*

Rewrite Eq. (113):

<sup>1</sup> � *<sup>P</sup> λ C*<sup>2</sup> � �

**6. Transmission factor**

**90**

Since,

<sup>¼</sup> �<sup>1</sup> *l*sinh *<sup>d</sup> l* � �*C*<sup>1</sup> <sup>þ</sup>

From Eq. (106) and Eq. (110), we get:

Substitute set Eq. (112) in Eq. (111), we get:

*<sup>C</sup>*<sup>2</sup> <sup>¼</sup> *<sup>C</sup>*<sup>1</sup> cosh *<sup>d</sup> l* � � <sup>þ</sup> *<sup>h</sup>*

> cosh *<sup>d</sup> l* � � þ *h*

<sup>1</sup> � *<sup>P</sup> λ C*<sup>2</sup> � �

From Eqs. (101) and (114), we get final relation:

cosh *β* þ

be numerically calculated by using the Newton-Raphson method.

to evolution radon diffusion coefficient by simple relation as:

*<sup>C</sup>*<sup>2</sup> <sup>¼</sup> *<sup>C</sup>*<sup>1</sup> cosh *<sup>d</sup> l* � � <sup>þ</sup> *<sup>λ</sup>lV*<sup>2</sup>

Substitute Eq. (109) in Eq. (107), we obtain:

� � �*C*<sup>1</sup> <sup>þ</sup> cosh *<sup>d</sup>*

*Recent Techniques and Applications in Ionizing Radiation Research*

*DeA* sinh *<sup>d</sup>*

cosh *<sup>d</sup> l* � � cosh *<sup>d</sup> α* � � � <sup>1</sup> *l*sinh *<sup>d</sup> l* � �

> *l* � �

> > *l* � �

*DeA* sinh *<sup>d</sup>*

<sup>1</sup> � cosh *<sup>d</sup>*

� *<sup>P</sup> λ C*<sup>2</sup> � �

� *<sup>P</sup> λ C*<sup>2</sup> � �

*<sup>C</sup>*<sup>2</sup> � <sup>1</sup> (117)

cosh *<sup>d</sup> l* � � <sup>þ</sup> *<sup>h</sup>*

� *<sup>C</sup>*<sup>1</sup> *C*2

*C*2

*<sup>d</sup> <sup>β</sup>* sinh *<sup>β</sup>* � *<sup>C</sup>*<sup>1</sup>

Eq. (115) is nonlinear equation; therefore, the radon diffusion coefficient *D* can

IF *β* is small, and by using set relation in Eq. (116), we can make approximation

We find simple relation to calculate the effective diffusion coefficient Eq. (117).

The purpose of using covers of cup (sponge or paper filter) to allow entry radon

and thoron gases only without its daughters for filter paper and radon only for

*De* <sup>¼</sup> *<sup>λ</sup> d h C*

*l* � �

*<sup>l</sup>* sinh *<sup>d</sup> l* � � *P*

<sup>1</sup> � cosh *<sup>d</sup>*

� � *P*

� 1

*λ*

*l* � � *P*

*<sup>C</sup>*<sup>2</sup> � cosh *<sup>d</sup>*

� �

cosh *<sup>d</sup> l* � � <sup>þ</sup> *<sup>λ</sup>lV*<sup>2</sup>

!

*P*

*<sup>λ</sup>* (109)

*<sup>λ</sup>* (111)

*<sup>λ</sup>* (113)

¼ 0 (114)

¼ 0 (115)

ð116Þ

(110)

ð112Þ

*l*sinh *<sup>d</sup> l* � �*C*<sup>2</sup> <sup>þ</sup>

*l* � �

*l* � � þ

*<sup>l</sup>* sinh *<sup>d</sup> l* � � þ

> *<sup>l</sup>* sinh *<sup>d</sup> l* � �

> > *h*

sponge. In actual terms it means that the covers are reduced from concentration inter cup to detection [16]. Therefore, we define transmission factor as the ratio between the concentrations inter cup and outside cup. The purpose from calculate diffusion coefficient and transmission factor to get actual radon concentration in air atmosphere. It is assumed that the gas enters the chamber through porous filter by the process of diffusion with diffusion coefficient *D*<sup>1</sup> and *D*<sup>2</sup> in air. If *C1* is the average radon/thoron gas concentration in the cup and *Co* is out the cup. Let the radon diffusion in x-direction **Figure 5** [1, 14, 16].

Then, the steady state equations for described the radon gas diffusion internal porous filter and in air space in cup may be written as Eq. (95), (*P* = 0, because of the lack of a source of radium) respectively:

$$\frac{d^2\mathbf{C}\_1(\mathbf{x})}{d\mathbf{x}^2} - \frac{\lambda}{D\_1}\mathbf{C}\_1(\mathbf{x}) = \mathbf{0} \tag{118}$$

$$\frac{d^2\mathbf{C}\_2(\mathbf{x})}{d\mathbf{x}^2} - \frac{\lambda}{D\_2}\mathbf{C}\_2(\mathbf{x}) = \mathbf{0} \tag{119}$$

The general solutions are

$$\mathbf{C}\_{1}(\mathbf{x}) = A\_{1}\mathbf{e}^{\mathbf{x}/l\_{1}} + B\_{1}\mathbf{e}^{-\mathbf{x}/l\_{1}} \tag{120}$$

$$\mathbf{C}\_{2}(\mathbf{x}) = \mathbf{A}\_{2}\mathbf{e}^{\mathbf{x}/l\_{2}} + \mathbf{B}\_{2}\mathbf{e}^{-\mathbf{x}/l\_{2}} \tag{121}$$

$$l\_1 = \sqrt{\frac{\rho\_1}{\lambda}} \quad \begin{array}{c} \\ \\ \hline \frac{D\_2}{\lambda} \end{array} \quad \begin{array}{c} \\ \\ \\ \hline \end{array} \tag{122}$$

where *A1, B1, A2, B2,* are integral constants obtained by boundary conditions, *l*1, *l*<sup>2</sup> are the diffusion length of radon (m), *D1, D2* are diffusion coefficients for porous filter and air respectively.

1.The boundary conditions at equilibrium at sides of porous filter are:

$$A\_1 e^{\delta\_{f\_1}} + B\_2 e^{-\delta\_{f\_1}} = \mathcal{C}\_o \qquad \text{at} \quad \mathbf{x} = -\delta$$

$$A\_1 + B\_1 = \mathcal{C}\_i \qquad \text{at} \quad \mathbf{x} = \mathbf{0}$$

The solutions of these equations are:

*Recent Techniques and Applications in Ionizing Radiation Research*

$$\begin{aligned} A\_1 &= \frac{e^{\delta/l\_1}}{e^{\delta/l\_1 - e^{-\delta/l\_1}}} C\_l - \frac{1}{e^{\delta/l\_1 - e^{-\delta/l\_1}}} C\_o \\ B\_1 &= \frac{e^{-\delta/l\_1}}{e^{\delta/l\_1 - e^{-\delta/l\_1}}} C\_l + \frac{1}{e^{\delta/l\_1 - e^{-\delta/l\_1}}} C\_o \end{aligned} \tag{124}$$

or

and

IF *<sup>δ</sup>*

*<sup>l</sup>*<sup>1</sup> is small sinh *<sup>δ</sup>*

**7. The calibration factor**

measured by *Track cm*�<sup>2</sup>

**93**

1 day = 86,400 sec and 1 m3 = 106 cm3

*Kexperement*

*dC*2ð Þ *x dx*

Substitute Eq. (134) in Eq. (133), we get:

*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

> *l*1 � � <sup>¼</sup> *<sup>δ</sup>*

From define transmission factor we get as:

� � � � *x*¼0

*Ci* <sup>¼</sup> *Co* cosh *<sup>δ</sup> l*1 � � <sup>þ</sup> *<sup>D</sup>*<sup>2</sup> *D*<sup>1</sup> *l*1 *<sup>l</sup>*<sup>2</sup> sinh *<sup>δ</sup> l*1 � � tanh *<sup>L</sup>*

*<sup>l</sup>*<sup>1</sup> and cosh *<sup>δ</sup>*

*C* ¼

*Transmission* ð Þ¼ %

relation between *Ktheoretical* and *Kexperement* in the can technique is:

*Bq* � *<sup>m</sup>*�<sup>3</sup> � *day* � � <sup>¼</sup> <sup>0</sup>*:*<sup>0864</sup> <sup>X</sup>

*Track cm*�<sup>2</sup>

*λ l*2*δ*

¼ � <sup>1</sup> *l*2

*l*1

*l*2 *L*

*<sup>D</sup>*<sup>1</sup> <sup>þ</sup> coth *<sup>L</sup>*

*C Co* ¼

Quantitative measurements with both single and multi-SSNT detectors device can be performed only if the calibration factor is known. It can be measured experimentally or estimated theoretically. Moreover, the theoretically derived calibration factor relations may supply reasonable basic design criteria. There are many method to deriving formulas of calibration factor such as Mont- Carlo, mean critical angle by unit cm. At the same time, the radon chamber is used to determine the calibration factors for different dosimeter geometry configuration [1, 17–19]. The theoretical calibration factor is calculated by unit (cm), while the experiment calibration factor is

*Bq*�*m*�3�*day* � �. Since 1 Bq = Disintegration/second = track/second,

, so, 1 cm = 0.0864 *Track cm*�<sup>2</sup>

*Ktheoretical*

*i*

tanh *<sup>L</sup> l*2

� � <sup>¼</sup> 1, we get:

*l*2

*λ l*2*δ*

*l*2 *L*

*<sup>D</sup>*<sup>1</sup> <sup>þ</sup> coth *<sup>L</sup>*

*l*2

� �*Ci* (134)

� � (135)

� � (137)

*Bq* �*m*�<sup>3</sup> �*day* � � [20]. The

*<sup>i</sup>* ð Þ *cm* (138)

*l*2

� �*Co* (136)

ð133Þ

From Eqs. (120) and (124), we get the general solution is:

$$\mathbf{C}\_{1}(\mathbf{x}) = \frac{\sinh\left(\frac{\mathbf{x} - \boldsymbol{\delta}}{l\_{1}}\right)}{\sinh\left(\frac{\boldsymbol{\delta}}{l\_{1}}\right)} \mathbf{C}\_{i} + \frac{\sinh\left(\frac{\boldsymbol{\chi}}{l\_{1}}\right)}{\sinh\left(\frac{\boldsymbol{\delta}}{l\_{1}}\right)} \mathbf{C}\_{o} \tag{125}$$

2.The boundary conditions at equilibrium in air space enter cup are:

$$\mathcal{C}\_2(\boldsymbol{x} = \mathbf{0}) = \mathcal{C}\_l \Bigg\acity\_{\mathcal{C}\_2(\boldsymbol{x})} \Bigg\bf \Bigg\bf \begin{pmatrix} \frac{d\mathcal{C}\_2(\boldsymbol{x})}{d\boldsymbol{x}} \end{pmatrix}\_{\mathcal{X} = \boldsymbol{L}} = \mathbf{0} \end{pmatrix} \tag{126}$$

We get two equations:

$$\begin{array}{ll} A\_2 + B\_2 = \left. C\_l \right|\_{l\_2 = \frac{B\_2}{l\_2}} & \text{at} \quad \left. \begin{array}{l} \text{at} = 0 \\ \left. \begin{array}{l} \text{at} \end{array} \right|\_{\frac{B\_2}{d}} = 0 \end{array} \right| \\ \left. \begin{array}{l} \text{at} \end{array} \right|\_{\frac{B\_2}{d}} = 0 \end{array} \quad \text{at} \quad \left. \begin{array}{l} \text{at} = 0 \\ \left. \begin{array}{l} \text{at} \end{array} \right|\_{\frac{B\_2}{d}} = 0 \end{array} \right) \end{array} \tag{127}$$

The solutions of these equations are:

$$\begin{aligned} A\_2 &= \left. \frac{e^{-L\_{f\_{l\_2}}}}{e^{L\_{f\_{l\_2}}} + e^{-L\_{f\_{l\_2}}}} C\_i \right| \\ B\_2 &= \left. \frac{e^{L\_{f\_{l\_2}}}}{e^{L\_{f\_{l\_2}}} + e^{-L\_{f\_{l\_2}}}} C\_i \right] \end{aligned} \tag{128}$$

From Eqs. (121) and (128), we get the general solution as:

$$\mathbf{C}\_{2}(\mathbf{x}) = \frac{\sinh\left(\frac{\mathbf{x} - L}{l\_{2}}\right)}{\sinh\left(\frac{L}{l\_{2}}\right)} \mathbf{C}\_{i} \tag{129}$$

The average concentration radon inter cup, we get from relation:

$$\overline{C} = \frac{1}{L} \int\_0^L C\_2(\varkappa) d\varkappa \tag{130}$$

The average concentration radon inter cup:

$$\overline{\mathbf{C}} = \frac{l\_2}{L} \tanh\left(\frac{L}{l\_2}\right) \mathbf{C}\_i \tag{131}$$

3.The boundary condition number 3 is:

$$\left.E\_1\right|\_{\mathbf{x}=\mathbf{0}} = \left.E\_2\right|\_{\mathbf{x}=\mathbf{0}}\tag{132}$$

*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

or

ð124Þ

ð126Þ

ð127Þ

ð128Þ

(130)

� � *Ci* (129)

*Ci* (131)

*<sup>x</sup>*¼<sup>0</sup> (132)

� �*Co* (125)

From Eqs. (120) and (124), we get the general solution is:

sinh *<sup>x</sup>*�*<sup>δ</sup> l*1 � � sinh *<sup>x</sup> l*1 � �

sinh *<sup>δ</sup> l*1

sinh *<sup>δ</sup> l*1 � � *Ci* <sup>þ</sup>

2.The boundary conditions at equilibrium in air space enter cup are:

*C*1ð Þ¼ *x*

*Recent Techniques and Applications in Ionizing Radiation Research*

We get two equations:

The solutions of these equations are:

From Eqs. (121) and (128), we get the general solution as:

*C*2ð Þ¼ *x*

The average concentration radon inter cup, we get from relation:

*<sup>C</sup>* <sup>¼</sup> <sup>1</sup> *L* ð*L* 0

*<sup>C</sup>* <sup>¼</sup> *<sup>l</sup>*<sup>2</sup>

*E*1j

The average concentration radon inter cup:

3.The boundary condition number 3 is:

**92**

sinh *<sup>x</sup>*�*<sup>L</sup> l*2 � �

sinh *<sup>L</sup> l*2

*C*2ð Þ *x dx*

*l*2 � �

*<sup>L</sup>* tanh *<sup>L</sup>*

*<sup>x</sup>*¼<sup>0</sup> ¼ *E*2j

$$\begin{aligned} \left. -D\_1 \frac{d\mathcal{C}\_1(\boldsymbol{x})}{d\boldsymbol{x}} \right|\_{\boldsymbol{x}=0} &= \left. -D\_2 \frac{d\mathcal{C}\_2(\boldsymbol{x})}{d\boldsymbol{x}} \right|\_{\boldsymbol{x}=0} \\\\ \left. \frac{d\mathcal{C}\_1(\boldsymbol{x})}{d\boldsymbol{x}} \right|\_{\boldsymbol{x}=0} &= \frac{1}{l\_1} \left\{ \frac{\cosh\left(\frac{\delta}{l\_1}\right)}{\sinh\left(\frac{\delta}{l\_1}\right)} \mathcal{C}\_t - \frac{1}{\sinh\left(\frac{\delta}{l\_1}\right)} \mathcal{C}\_o \right\} \end{aligned} \tag{133}$$

and

$$\left. \frac{d\mathbf{C}\_2(\mathbf{x})}{d\mathbf{x}} \right|\_{\mathbf{x}=\mathbf{0}} = -\frac{1}{l\_2} \tanh\left(\frac{L}{l\_2}\right) \mathbf{C}\_i \tag{134}$$

Substitute Eq. (134) in Eq. (133), we get:

$$C\_i = \frac{C\_o}{\cosh\left(\frac{\delta}{l\_1}\right) + \frac{D\_2}{D\_1}\frac{l\_1}{l\_2}\sinh\left(\frac{\delta}{l\_1}\right)\tanh\left(\frac{L}{l\_2}\right)}\tag{135}$$

IF *<sup>δ</sup> <sup>l</sup>*<sup>1</sup> is small sinh *<sup>δ</sup> l*1 � � <sup>¼</sup> *<sup>δ</sup> <sup>l</sup>*<sup>1</sup> and cosh *<sup>δ</sup> l*1 � � <sup>¼</sup> 1, we get:

$$\overline{C} = \frac{\frac{l\_2}{L}}{\frac{\lambda \cdot l\_2 \delta}{D\_1} + \coth\left(\frac{L}{l\_2}\right)} C\_o \tag{136}$$

From define transmission factor we get as:

$$Transmission\ (\text{\(\(6\)} = \frac{\overline{C}}{C\_o} = \frac{\frac{L}{L}}{\frac{\lambda \cdot l\_2 \delta}{D\_1} + \coth\left(\frac{L}{l\_2}\right)}\tag{137}$$

#### **7. The calibration factor**

Quantitative measurements with both single and multi-SSNT detectors device can be performed only if the calibration factor is known. It can be measured experimentally or estimated theoretically. Moreover, the theoretically derived calibration factor relations may supply reasonable basic design criteria. There are many method to deriving formulas of calibration factor such as Mont- Carlo, mean critical angle by unit cm. At the same time, the radon chamber is used to determine the calibration factors for different dosimeter geometry configuration [1, 17–19]. The theoretical calibration factor is calculated by unit (cm), while the experiment calibration factor is measured by *Track cm*�<sup>2</sup> *Bq*�*m*�3�*day* � �. Since 1 Bq = Disintegration/second = track/second, 1 day = 86,400 sec and 1 m3 = 106 cm3 , so, 1 cm = 0.0864 *Track cm*�<sup>2</sup> *Bq* �*m*�<sup>3</sup> �*day* � � [20]. The relation between *Ktheoretical* and *Kexperement* in the can technique is:

$$K\_{\text{experiment}} \left(\frac{\text{Tract } cm^{-2}}{Bq \cdot m^{-3} \cdot day}\right) = 0.0864 \sum\_{i} K\_{i}^{theoretical} (cm) \tag{138}$$

### **8. Conclusion remarks**


**Author details**

**95**

Ali Farhan Nader Alrekabi

Iraq Oil Ministry/Basra Oil Company, Basra University, Basra, Iraq

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

\*Address all correspondence to: alialrekabi251@gmail.com

provided the original work is properly cited.

*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

### **Acknowledgements**

I would like to express my deep appreciation to:


My great thanks to all which they could assistance me in any way.

*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

**8. Conclusion remarks**

concentration.

fraction.

factor.

**94**

**Acknowledgements**

• Department of physics

out of the container Eq. (10).

concentration as shown in **Table 1**.

are liner equations **Table 2**.

1.The concentration of radon emanated from each sample inside the closed container reach to the steady state after a fixed period of time without leakage

2.The detector should be exposed for at least 27 day to record tracks for radon

3.The radon concentration reaches the equilibrium state at the same time

4.There are three different quantities measured by track density, integrated radon concentration, average radon concentration and saturate radon

5.From the relations in **Table 2**, we get some relationship between radon concentration, area and mass radon exhalation and effective radium content

6.The radon/thoron concentrations equations which used in technique two different SSNTDs are very critical because it's a mathematical relationship as a

7.For more accurate estimation of the effective dose from radon/thoron exposure, one should measure the equilibrium factor at each site.

interest in ventilation factor when houses and buildings design.

I would like to express my deep appreciation to:

• My supervisor Prof. Dr. Abdul Ridha Hussein Subber

• Education College for Pure Science, Basra University

• Dr. Basim Almayahi and IntechOpen publishing

• Oil Ministry, Gas Filling Company and My Company (Basra Oil)

My great thanks to all which they could assistance me in any way.

8.High dose does not necessarily mean there is a high concentration of radon, there may be high equilibrium factor (bad ventilation), and so we recommend

9. It is necessary to correct the radon concentration when using covers (sponge or filter paper) in measurements of radon concentration by transmission

(t ffi 7T\_(1/2)) regardless of the volume of the container.

*Recent Techniques and Applications in Ionizing Radiation Research*

#### **Author details**

Ali Farhan Nader Alrekabi Iraq Oil Ministry/Basra Oil Company, Basra University, Basra, Iraq

\*Address all correspondence to: alialrekabi251@gmail.com

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

### **References**

[1] Nader AF. Theoretical and Experimental Study to Evaluate Radioactivity Applied on a Selected Area in Basra Governorate [thesis]. Basra, Iraq: University of Basra, Iraq; 2015

[2] Abd-Elzaher M. An overview on studying 222Rn exhalation rates using passive technique solid-state nuclear track detectors. American Journal of Applied Sciences. 2012;**9**(10):1653-1659

[3] Tufail M, Mirza SM, Mahmood A, Qureshi AA. Application of a closed-can technique for measuring radon exhalation from mine samples of Punjab, Pakistan. Journal of Environmental Radioactivity. 2000;**50**: 267-275

[4] Jiang H, Liangquan GE, Lin Y, Yi GU. Preliminary study on a regional radon concentration in surface soil prediction method. Progress in Nuclear Science and Technology. 2011;**1**:364-367

[5] Byun SH. Radioactivity: Radioisotopes and Radiation Methodology Lecture Notes. Canada: University of McMaster; 2014

[6] Saad AF, Abdalla YK, Hussein NA, Elyaseery IS. Radon exhalation rate from building material used on the Garyounis. University campus, Benghazi Libya,Turkish. Journal of Environmental Science and Engineering. 2010;**34**:67-74

[7] Eman SA, Nageeb SH, El-Sersy AR. U and Th determination in natural samples using CR-39 and LR-115 track detectors. World Journal of Nuclear Science and Technology. 2012;**2**:36-40

[8] Koo VSY, Yip CWY, Ho JPY, Nikezik D, Yu KN. Sensitivity of LR- 115 detector in diffusion chamber to Rn<sup>222</sup> in the presence of Rn220. Applied Radiation and Isotopes. 2002;**56**:953-956 [9] Yu KN, Nikezic D. Long-Term measurements of radon progeny concentration with solid-state nuclear track detectors. Radiation Measurements. 2005;**40**:560-568

in cup dosimeter. Radiation Measurements. 2008;**43**:418-421

NHN. Numerical and analytical

factor for CR-39 detectors in the chamber diffusion by using Monte-Carlo method and the mean critical angle. Scholars Research Library. 2014;

**5**:23-30

2014;**3**:48-52

[17] Nader AF, Subber ARH, Al-Hashimi

*Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

calculations of efficiency and calibration

[18] Nader AF, Subber ARH, Al-Hashimi NHN. Mathematical calculation to find the best chamber and detector radii used for measurements the range of αparticle. The International Journal of Engineering & Science (THE IJES).

[19] Subber ARH, Al-Hashmi NHN, Nader AF, Jebur JH, Khodier MK. Construct as a simple radon chamber for

measurement of radon detectors calibration factors. Pelagia Research

[20] Ismail AH, Jaafar MS. Experimental measurement on CR-39 response for radon gas and estimation the optimum dimension of dosimeters for detection of radon. In: Proceeding of the 3ed Asian Physics Symposinum. Bandung,

Library. 2015;**6**:128-131

Indonesia; 2009

**97**

[10] Somogyi G, Paripas B, Varga Z. Measurement of radon, radon daughters and thoron concentration by multidetector devices. Nuclear Tracks and Radiation Measurements. 1984;**8**(1–4): 423-427

[11] Nader AF. The determination of equilibrium factor of radon and thoron using LR-115 type II detector in a selected area from Basra governorate, Iraq. Journal of Physics Conference Series. 2019;**1258**:012032

[12] UNSCEAR. United Nations scientific committee on the effects of atomic radiation, annex D, distribution. Applied Radiation and Isotopes. 1982; **54**:467-473

[13] Abo-Elmaged M, Mansy M, Eissa HM, El-Fiki MA. Major parameters affecting the calculation of equilibrium factor using SSNTD-measured track densities. Radiation Measurements. 2006;**41**:235-240

[14] Hosoda M, Tokonami S, Sorimachi A, Janik M, Ishikaw T, Yatabe Y, et al. Experimental system to evaluate the effective diffusion coefficient of radon. Review of Scientific Instruments. 2009;**80**:013501

[15] Nader AF, Juber JH, Subber ARH, Al-Hashimi NHN. The diffusion coefficient and calibration factors for indoor radon measurement in bare and twin cup modes. Journal of Zankoy Sulaimani-A. 2016;**18**(1):49-56

[16] Eappen KP, Sahoo BK, Ramachandran TV, Mayya YS. Calibration factor for thoron estimation *Mathematical Expressions of Radon Measurements DOI: http://dx.doi.org/10.5772/intechopen.92647*

in cup dosimeter. Radiation Measurements. 2008;**43**:418-421

**References**

2015

267-275

[1] Nader AF. Theoretical and Experimental Study to Evaluate Radioactivity Applied on a Selected Area in Basra Governorate [thesis]. Basra, Iraq: University of Basra, Iraq;

*Recent Techniques and Applications in Ionizing Radiation Research*

[9] Yu KN, Nikezic D. Long-Term measurements of radon progeny concentration with solid-state nuclear

[10] Somogyi G, Paripas B, Varga Z. Measurement of radon, radon daughters and thoron concentration by multidetector devices. Nuclear Tracks and Radiation Measurements. 1984;**8**(1–4):

[11] Nader AF. The determination of equilibrium factor of radon and thoron using LR-115 type II detector in a selected area from Basra governorate, Iraq. Journal of Physics Conference

Series. 2019;**1258**:012032

[12] UNSCEAR. United Nations scientific committee on the effects of atomic radiation, annex D, distribution. Applied Radiation and Isotopes. 1982;

[13] Abo-Elmaged M, Mansy M,

[14] Hosoda M, Tokonami S, Sorimachi A, Janik M, Ishikaw T, Yatabe Y, et al. Experimental system to

evaluate the effective diffusion coefficient of radon. Review of

[16] Eappen KP, Sahoo BK, Ramachandran TV, Mayya YS.

Scientific Instruments. 2009;**80**:013501

[15] Nader AF, Juber JH, Subber ARH, Al-Hashimi NHN. The diffusion coefficient and calibration factors for indoor radon measurement in bare and twin cup modes. Journal of Zankoy Sulaimani-A. 2016;**18**(1):49-56

Calibration factor for thoron estimation

Eissa HM, El-Fiki MA. Major parameters affecting the calculation of equilibrium factor using SSNTD-measured track densities. Radiation Measurements.

track detectors. Radiation Measurements. 2005;**40**:560-568

423-427

**54**:467-473

2006;**41**:235-240

[2] Abd-Elzaher M. An overview on studying 222Rn exhalation rates using passive technique solid-state nuclear track detectors. American Journal of Applied Sciences. 2012;**9**(10):1653-1659

[3] Tufail M, Mirza SM, Mahmood A, Qureshi AA. Application of a closed-can

Environmental Radioactivity. 2000;**50**:

[4] Jiang H, Liangquan GE, Lin Y, Yi GU. Preliminary study on a regional radon concentration in surface soil prediction method. Progress in Nuclear Science and Technology. 2011;**1**:364-367

Methodology Lecture Notes. Canada: University of McMaster; 2014

[6] Saad AF, Abdalla YK, Hussein NA, Elyaseery IS. Radon exhalation rate from building material used on the Garyounis. University campus, Benghazi Libya,Turkish. Journal of

[7] Eman SA, Nageeb SH, El-Sersy AR. U

Nikezik D, Yu KN. Sensitivity of LR- 115 detector in diffusion chamber to Rn<sup>222</sup> in the presence of Rn220. Applied

Radiation and Isotopes. 2002;**56**:953-956

and Th determination in natural samples using CR-39 and LR-115 track detectors. World Journal of Nuclear Science and Technology. 2012;**2**:36-40

[8] Koo VSY, Yip CWY, Ho JPY,

**96**

[5] Byun SH. Radioactivity: Radioisotopes and Radiation

Environmental Science and Engineering. 2010;**34**:67-74

technique for measuring radon exhalation from mine samples of Punjab, Pakistan. Journal of

[17] Nader AF, Subber ARH, Al-Hashimi NHN. Numerical and analytical calculations of efficiency and calibration factor for CR-39 detectors in the chamber diffusion by using Monte-Carlo method and the mean critical angle. Scholars Research Library. 2014; **5**:23-30

[18] Nader AF, Subber ARH, Al-Hashimi NHN. Mathematical calculation to find the best chamber and detector radii used for measurements the range of αparticle. The International Journal of Engineering & Science (THE IJES). 2014;**3**:48-52

[19] Subber ARH, Al-Hashmi NHN, Nader AF, Jebur JH, Khodier MK. Construct as a simple radon chamber for measurement of radon detectors calibration factors. Pelagia Research Library. 2015;**6**:128-131

[20] Ismail AH, Jaafar MS. Experimental measurement on CR-39 response for radon gas and estimation the optimum dimension of dosimeters for detection of radon. In: Proceeding of the 3ed Asian Physics Symposinum. Bandung, Indonesia; 2009

**99**

Section 3

Applications in Ionizing

Radiation

## Section 3

## Applications in Ionizing Radiation

**101**

cancer [6–8].

(

**Chapter 7**

**Abstract**

presented.

palladium, rhodium

**1. Introduction**

is radioisotope production [2].

Production of the 103Pd via

Brachytherapy Seed

*Pooneh Saidi and Mahdi Sadeghi*

Cyclotron and Preparation of the

This study will briefly explain the production of 103Pd via cyclotron for brachy-

**Keywords:** brachytherapy, cyclotron, production, cross-section, excitation function,

Cyclotrons are charged particle circular accelerators. They are a type of particle accelerator that has many applications in nuclear physics, industry, technology, and medicine. They play an important role in medicine; for example, they are used for radiation therapy, production of medical radioisotopes, and biomedical research [1]. As a particle accelerator, one of the important uses of the cyclotron in medicine

For a long period, radioisotope production is basically done in nuclear reactors, but their availability is slowly decreasing, and due to some advantages of radioisotope production with the cyclotron, the development of particle accelerators started in the past century, so accelerator-based production facilities are growing, and

In this chapter, the production method for the radioisotope, Palladium-103

103Pd), via cyclotron is discussed. Palladium-103 with energy emission about 20 keV results in the rapid dose falloff with the distance which is suitable for low-dose-rate (LDR) brachytherapy [3]. For nearly 25 years, brachytherapy sources containing 103Pd have been clinically introduced and are in use [4, 5]. Sources containing 103Pd are most commonly used in the treatment of prostate and eye

various radioisotopes suitable for medical applications are produced.

therapy use. The excitation functions of 103Rh(p,n)103Pd and 103Rh(d,2n)103Pd reactions were calculated using ALICE/91, ALICE/ASH, and TALYS-1.2 codes and compared with published data. Production of 103Pd was done via 103Rh(p,n)103Pd nuclear reaction. The target was bombarded with 18 MeV protons at 200 μA beam current for 15 h. After irradiation and radiochemical separation of the electroplated rhodium target, at the optimum condition, 103Pd was absorbed into Amberlite®IR-93 resin. The preparation of the brachytherapy seed, which is loaded by the resin beads, has also been presented. At least, the method to determine the dosimetric parameters for the seed by experimental measurement has been

#### **Chapter 7**

## Production of the 103Pd via Cyclotron and Preparation of the Brachytherapy Seed

*Pooneh Saidi and Mahdi Sadeghi*

#### **Abstract**

This study will briefly explain the production of 103Pd via cyclotron for brachytherapy use. The excitation functions of 103Rh(p,n)103Pd and 103Rh(d,2n)103Pd reactions were calculated using ALICE/91, ALICE/ASH, and TALYS-1.2 codes and compared with published data. Production of 103Pd was done via 103Rh(p,n)103Pd nuclear reaction. The target was bombarded with 18 MeV protons at 200 μA beam current for 15 h. After irradiation and radiochemical separation of the electroplated rhodium target, at the optimum condition, 103Pd was absorbed into Amberlite®IR-93 resin. The preparation of the brachytherapy seed, which is loaded by the resin beads, has also been presented. At least, the method to determine the dosimetric parameters for the seed by experimental measurement has been presented.

**Keywords:** brachytherapy, cyclotron, production, cross-section, excitation function, palladium, rhodium

#### **1. Introduction**

Cyclotrons are charged particle circular accelerators. They are a type of particle accelerator that has many applications in nuclear physics, industry, technology, and medicine. They play an important role in medicine; for example, they are used for radiation therapy, production of medical radioisotopes, and biomedical research [1]. As a particle accelerator, one of the important uses of the cyclotron in medicine is radioisotope production [2].

For a long period, radioisotope production is basically done in nuclear reactors, but their availability is slowly decreasing, and due to some advantages of radioisotope production with the cyclotron, the development of particle accelerators started in the past century, so accelerator-based production facilities are growing, and various radioisotopes suitable for medical applications are produced.

In this chapter, the production method for the radioisotope, Palladium-103 ( 103Pd), via cyclotron is discussed. Palladium-103 with energy emission about 20 keV results in the rapid dose falloff with the distance which is suitable for low-dose-rate (LDR) brachytherapy [3]. For nearly 25 years, brachytherapy sources containing 103Pd have been clinically introduced and are in use [4, 5]. Sources containing 103Pd are most commonly used in the treatment of prostate and eye cancer [6–8].


#### **Table 1.**

*Examples of radioisotopes commonly used in brachytherapy.*

Brachytherapy is a form of treatment where a sealed radioactive source placed on or in the tissue/tumor is to be irradiated. With this method, a high dose can be delivered to the tumor with a rapid decrease in dose in the surrounding normal tissue. Brachytherapy sources are usually encapsulated; the encapsulated sources are placed within the body cavities close to the tumor, in a lumen of organs, or implanted into the tumor or placed over the tissue to be radiated.

Depending on the source dose rate, brachytherapy sources are classified into three categories [9]:


**Table 1** shows examples of radioisotopes commonly used in brachytherapy for the three mentioned categories [10].

This study will briefly explain the production of the 103Pd via cyclotron and will shortly describe some detail of 103Pd production such as production process, targetry, radiochemical separation, seed fabrication, and seed dosimetry method.

#### **2. Materials and methods**

#### **2.1 Cyclotron production of 103Pd**

There are different methods for the production of 103Pd via cyclotron. Two of them are 103Rh(p,n)103Pd and 103Rh(d,2n)103Pd [3]. In this study, the excitation functions for both reactions have been calculated, and the optimum condition for each reaction has been obtained. Experimental data for the proton bombardment on rhodium metal as the target, via 103Rh(p,n)103Pd reaction, has also been measured. Rhodium target has been bombarded by proton in a cyclotron (Cyclone-30, IBA)

**103**

sufficient.

*Production of the 103Pd via Cyclotron and Preparation of the Brachytherapy Seed*

with 18 MeV energy and a beam current intensity of 200 μA at the Agricultural,

To achieve the 103Pd from the irradiated target, the radiochemical separation stage is started. The problem in this stage is the dissolution of target material due to the extremely low chemical reactivity of rhodium metal. The other problem is the high quantity of rhodium in the solution. A well-known palladium extractor is dimethylglyoxime, but to prevent the decrease of extraction yield, α-furyldioxime has been used [12]. Purely obtained 103Pd is then absorbed into resin; the active

Excitation functions of the 103Rh(p,n)103Pd and 103Rh(d,2n)103Pd reactions were calculated using ALICE/ASH, EMPIRE (version 3.1 Rivoli) and TALYS-1.2 nuclear codes, and the TENDL-2010. Using the codes simultaneously increases the accuracy of calculations. The calculated results were compared to the existing data of

The ALICE/ASH code: This code is a modified version of the ALICE code, and to describe the pre-equilibrium particle emission from nuclei, the geometry-dependent hybrid model (GDH) is used. Calculations were carried out based on the Fermi gas model with the nuclear level density parameter a = A/y and the generalized

The TALYS code: TALYS is a computer code developed at NRG Petten and CEA to predict and analyze the nuclear reactions. TALYS models the nuclear reactions that involve protons, deuterons, neutrons, alpha particles, gamma rays, tritons, and hellions. The code simulated the reactions in the energy range from 1 keV to

EMPIRE: EMPIRE (version 3.1 Rivoli) simulates various nuclear reactions, over a broad range of energies and incident particles. This system can be used for nuclear data evaluation and also for the theoretical calculation of nuclear reactions. A projectile can be a photon, a nucleon, and light or heavy ion. There is a broad range of energy in the system; the energy range starts just above the resonance region in the case of a neutron projectile and extends up to a few hundred MeV for heavy

The required thickness of the target has been calculated via the stopping and range of ions in matter (SRIM) code [21]. Based on the code results, to take full advantage of the excitation function and also to avoid the production of the radioisotope impurity, the entrance energy of the proton should be 18 MeV. The physical thickness of the rhodium layer is chosen in such a way that for a given beam/ target angle geometry, the particle exit energy should be 6 MeV. The thickness of the rhodium target has to be 475 μm for 90° geometry. To minimize the thickness of the rhodium layer (and hence lower the cost price per target), a 6° geometry is preferred; in this case, the thickness of the target decreases, and a 45–50 μm layer is

Identification of the gamma ray emitting from the radionuclides is performed by using gamma-ray spectroscopy with a high-purity germanium HP(Ge) detector

*DOI: http://dx.doi.org/10.5772/intechopen.92457*

Medical and Industrial Research School (AMIRS) [11].

resins are encapsulated inside the titanium casing.

**2.3 Nuclear models applied for cross-section calculations**

superfluid nuclear model. The default value of y is equal to [17, 19].

200 MeV, for target nuclides of mass 12 and heavier [14, 17].

**2.2 Calculation of excitation function**

references [13–18].

ion-induced reactions [20].

**2.4 The thickness of the target**

(Canberra™ model GC1020-7500SL).

*Production of the 103Pd via Cyclotron and Preparation of the Brachytherapy Seed DOI: http://dx.doi.org/10.5772/intechopen.92457*

with 18 MeV energy and a beam current intensity of 200 μA at the Agricultural, Medical and Industrial Research School (AMIRS) [11].

To achieve the 103Pd from the irradiated target, the radiochemical separation stage is started. The problem in this stage is the dissolution of target material due to the extremely low chemical reactivity of rhodium metal. The other problem is the high quantity of rhodium in the solution. A well-known palladium extractor is dimethylglyoxime, but to prevent the decrease of extraction yield, α-furyldioxime has been used [12]. Purely obtained 103Pd is then absorbed into resin; the active resins are encapsulated inside the titanium casing.

#### **2.2 Calculation of excitation function**

*Recent Techniques and Applications in Ionizing Radiation Research*

Brachytherapy is a form of treatment where a sealed radioactive source placed on or in the tissue/tumor is to be irradiated. With this method, a high dose can be delivered to the tumor with a rapid decrease in dose in the surrounding normal tissue. Brachytherapy sources are usually encapsulated; the encapsulated sources are placed within the body cavities close to the tumor, in a lumen of organs, or

**Radionuclide T1/2 Mode of decay The energy of the emitted particle (keV)**

32P 14.26 d β−(100) 690 137Cs 30.04 y β−(100) 662 198Ir 73.8 β−(95.34) 380 198Au 2.69 β−(100) 412 125I 59.4 d EC (100) 28 169Yb 32.02 d EC (100) 93 103Pd 16.99 d EC (100) 21 153Sm 46.28 h β−(100) 223 142Pr 19.12 β−(96.3) 809 170Tm 128.6 d β−(99.87) 66.39

Depending on the source dose rate, brachytherapy sources are classified into

• High-dose-rate sources (HDR): >12 Gy/h radioisotopes with high-energy

• Medium-dose-rate sources (MDR): 2–12 Gy/h radioisotopes are used; this

• Low-dose-rate sources (LDR): Less than 2 Gy/h radioisotopes with low-energy

**Table 1** shows examples of radioisotopes commonly used in brachytherapy for

This study will briefly explain the production of the 103Pd via cyclotron and will shortly describe some detail of 103Pd production such as production process, targetry, radiochemical separation, seed fabrication, and seed dosimetry method.

There are different methods for the production of 103Pd via cyclotron. Two of them are 103Rh(p,n)103Pd and 103Rh(d,2n)103Pd [3]. In this study, the excitation functions for both reactions have been calculated, and the optimum condition for each reaction has been obtained. Experimental data for the proton bombardment on rhodium metal as the target, via 103Rh(p,n)103Pd reaction, has also been measured. Rhodium target has been bombarded by proton in a cyclotron (Cyclone-30, IBA)

implanted into the tumor or placed over the tissue to be radiated.

*Examples of radioisotopes commonly used in brachytherapy.*

photon emitters like 137Cs, 60Co, 192Ir, and 198Au are used.

category is not commonly used in brachytherapy.

photon emitters like 103Pd and 125I are used.

the three mentioned categories [10].

**2. Materials and methods**

**2.1 Cyclotron production of 103Pd**

three categories [9]:

**Table 1.**

**102**

Excitation functions of the 103Rh(p,n)103Pd and 103Rh(d,2n)103Pd reactions were calculated using ALICE/ASH, EMPIRE (version 3.1 Rivoli) and TALYS-1.2 nuclear codes, and the TENDL-2010. Using the codes simultaneously increases the accuracy of calculations. The calculated results were compared to the existing data of references [13–18].

#### **2.3 Nuclear models applied for cross-section calculations**

The ALICE/ASH code: This code is a modified version of the ALICE code, and to describe the pre-equilibrium particle emission from nuclei, the geometry-dependent hybrid model (GDH) is used. Calculations were carried out based on the Fermi gas model with the nuclear level density parameter a = A/y and the generalized superfluid nuclear model. The default value of y is equal to [17, 19].

The TALYS code: TALYS is a computer code developed at NRG Petten and CEA to predict and analyze the nuclear reactions. TALYS models the nuclear reactions that involve protons, deuterons, neutrons, alpha particles, gamma rays, tritons, and hellions. The code simulated the reactions in the energy range from 1 keV to 200 MeV, for target nuclides of mass 12 and heavier [14, 17].

EMPIRE: EMPIRE (version 3.1 Rivoli) simulates various nuclear reactions, over a broad range of energies and incident particles. This system can be used for nuclear data evaluation and also for the theoretical calculation of nuclear reactions. A projectile can be a photon, a nucleon, and light or heavy ion. There is a broad range of energy in the system; the energy range starts just above the resonance region in the case of a neutron projectile and extends up to a few hundred MeV for heavy ion-induced reactions [20].

#### **2.4 The thickness of the target**

The required thickness of the target has been calculated via the stopping and range of ions in matter (SRIM) code [21]. Based on the code results, to take full advantage of the excitation function and also to avoid the production of the radioisotope impurity, the entrance energy of the proton should be 18 MeV. The physical thickness of the rhodium layer is chosen in such a way that for a given beam/ target angle geometry, the particle exit energy should be 6 MeV. The thickness of the rhodium target has to be 475 μm for 90° geometry. To minimize the thickness of the rhodium layer (and hence lower the cost price per target), a 6° geometry is preferred; in this case, the thickness of the target decreases, and a 45–50 μm layer is sufficient.

Identification of the gamma ray emitting from the radionuclides is performed by using gamma-ray spectroscopy with a high-purity germanium HP(Ge) detector (Canberra™ model GC1020-7500SL).

### **2.5 Preparation of 103Pd brachytherapy seeds**

After irradiation, the radiochemical separation phase has been started. In this phase, the PdCl2 solution has been separated from rhodium, zinc, and copper.

According to the brachytherapy seed model (in case of using a sphere made of resin), resin beads and marker are encapsulated inside the titanium capsule. The end caps of the capsule are welded precisely to prevent source leakage [22]. Regarding the physical design and configuration of the source internal component, two types of designs have been used: (a) rod/wire/cylinder made of ceramic, glass, or high-Z materials and (b) sphere made of resin. In this study sphere design of the source has been discussed.

**Figure 1** shows a schematic diagram of eight different brachytherapy seeds which are designed at the Agricultural, Medical, and Industrial Research School [7, 23–25].

#### **2.6 Dosimetry of the seed**

According to the American Association of Physicists in Medicine (AAPM) Radiation Therapy Committee recommendation, the dosimetry characteristics

**105**

**Figure 2.**

*experimental data [10].*

*Production of the 103Pd via Cyclotron and Preparation of the Brachytherapy Seed*

for all new interstitial brachytherapy seeds with energies less than 50 keV should be investigated by two independent investigators, theoretical calculations and experimental measurements. This work presents the method for thermoluminescent dosimeter (TLD) measurements to determine the dosimetric characteristics of the brachytherapy seed containing resin beads. The TLD-GR200A thermoluminescent dosimeters and two Perspex phantoms have been used, one Perspex phantom for the anisotropy function, *F(r, θ)*, and the other for the radial dose

The evaluation of the acquired data from the codes showed that the best range of the energy for proton in the 103Rh(p,n)103Pd reaction is 18–8 MeV. The maximum cross-section by EMPIRE (version 3.1 Rivoli) code is at Ep = 10 MeV, and the value is 574.44 mb. To evaluate the obtained results, **Figure 2** shows the comparison between the calculated results in this study and measured data by others. For the 103Rh(p,n)103Pd reaction, there are five cross-section measurements that exist in the

The calculated results from the TENDL-201, TALYS-1.2, and ALICE/ASH codes

According to the results from the codes, the optimum range of energy of the deuteron particle to produce 103Pd from 103Rh target for the 103Rh(d,2n)103Pd reaction is 22 to 8 MeV. The obtained results from ALICE/ASH hybrid model (a = A/9)

*Excitation function of 103Rh(p,n)103Pd reaction by ALICE/91, ALICE/ASH and TALYS-1.2 codes, and* 

are in acceptable agreement with the measured data from [29], and calculated results from EMPIRE (version 3.1 Rivoli) code are in good agreement with the

*DOI: http://dx.doi.org/10.5772/intechopen.92457*

function, *gL(r)*.

**3. Results and discussion**

*3.1.1 Excitation function study of 103Rh(p,n)103Pd reaction*

literature by authors of references [26–29].

Hermanne et al. measured data (**Figure 2**).

*3.1.2 Excitation function study of 103Rh(d,2n)103Pd reaction*

**3.1 Excitation function**

**Figure 1.**

*Schematic drawing of the designed 103Pd sources.*

*Production of the 103Pd via Cyclotron and Preparation of the Brachytherapy Seed DOI: http://dx.doi.org/10.5772/intechopen.92457*

for all new interstitial brachytherapy seeds with energies less than 50 keV should be investigated by two independent investigators, theoretical calculations and experimental measurements. This work presents the method for thermoluminescent dosimeter (TLD) measurements to determine the dosimetric characteristics of the brachytherapy seed containing resin beads. The TLD-GR200A thermoluminescent dosimeters and two Perspex phantoms have been used, one Perspex phantom for the anisotropy function, *F(r, θ)*, and the other for the radial dose function, *gL(r)*.

#### **3. Results and discussion**

#### **3.1 Excitation function**

*Recent Techniques and Applications in Ionizing Radiation Research*

After irradiation, the radiochemical separation phase has been started. In this phase, the PdCl2 solution has been separated from rhodium, zinc, and copper. According to the brachytherapy seed model (in case of using a sphere made of resin), resin beads and marker are encapsulated inside the titanium capsule. The end caps of the capsule are welded precisely to prevent source leakage [22]. Regarding the physical design and configuration of the source internal component, two types of designs have been used: (a) rod/wire/cylinder made of ceramic, glass, or high-Z materials and (b) sphere made of resin. In this study sphere design of the

**Figure 1** shows a schematic diagram of eight different brachytherapy seeds which are designed at the Agricultural, Medical, and Industrial Research School

According to the American Association of Physicists in Medicine (AAPM) Radiation Therapy Committee recommendation, the dosimetry characteristics

**2.5 Preparation of 103Pd brachytherapy seeds**

source has been discussed.

**2.6 Dosimetry of the seed**

[7, 23–25].

**104**

**Figure 1.**

*Schematic drawing of the designed 103Pd sources.*

#### *3.1.1 Excitation function study of 103Rh(p,n)103Pd reaction*

The evaluation of the acquired data from the codes showed that the best range of the energy for proton in the 103Rh(p,n)103Pd reaction is 18–8 MeV. The maximum cross-section by EMPIRE (version 3.1 Rivoli) code is at Ep = 10 MeV, and the value is 574.44 mb. To evaluate the obtained results, **Figure 2** shows the comparison between the calculated results in this study and measured data by others. For the 103Rh(p,n)103Pd reaction, there are five cross-section measurements that exist in the literature by authors of references [26–29].

The calculated results from the TENDL-201, TALYS-1.2, and ALICE/ASH codes are in acceptable agreement with the measured data from [29], and calculated results from EMPIRE (version 3.1 Rivoli) code are in good agreement with the Hermanne et al. measured data (**Figure 2**).

#### *3.1.2 Excitation function study of 103Rh(d,2n)103Pd reaction*

According to the results from the codes, the optimum range of energy of the deuteron particle to produce 103Pd from 103Rh target for the 103Rh(d,2n)103Pd reaction is 22 to 8 MeV. The obtained results from ALICE/ASH hybrid model (a = A/9)

#### **Figure 2.**

*Excitation function of 103Rh(p,n)103Pd reaction by ALICE/91, ALICE/ASH and TALYS-1.2 codes, and experimental data [10].*

show that the maximum cross-section is 1158.795 mb (Ed = 13 MeV). Comparison between the calculated results of this study and the measured data obtained by [30, 31] is presented in **Figure 3**.

The obtained results from ALICE/ASH code are in good agreement with the measured data by Hermanne et al. up to 20 MeV, whereas TALYS-1.2 and EMPIRE (version 3.1 Rivoli) calculated results have lower values than ALICE/ASH results and also experimental data.

#### **3.2 Production of 103Pd**

To prepare the rhodium target for irradiation, via the electrodeposition process, a thick layer of rhodium has been placed of the copper backing. According to Sadeghi et al. study [11, 12], the following conditions are the optimum conditions for the electrodeposition:


After the electrodeposition process, the adhesion quality of the rhodium layer on the target backing has been tested by the thermal shock. The thermal shock has been carried out by heating the target up to 500°C for 1 h (The temperature that the Rh layer experience during high current irradiation). Thereafter, the hot target is submerged in cold water in a temperature of about 15°C. Observation of neither crack formation nor peeling off of the rhodium layers indicated a good adhesion for the purpose.

Afterward, the rhodium target was bombarded with 18 MeV protons at 200 μA beam current for 15 h (3000 μAh) [12]. At the end of the bombardment (EOB),

#### **Figure 3.**

*Excitation function of 103Rh(d,2n)103Pd reaction by ALICE/91, ALICE/ASH and TALYS-1.2 codes, and experimental data [10].*

**107**

**Figure 4.**

*Production of the 103Pd via Cyclotron and Preparation of the Brachytherapy Seed*

The optimum conditions of the electro-dissolution are as follows:

the activity of 103Pd and the yield of production are 685 mCi and 8.44 MBq/lAh, respectively. After the proton bombardment, the dissolution process has been started.

After the dissolution of the target from copper backing, the residual contains PdCl2, rhodium, zinc, and copper, so during the radiochemical separation phase, the PdCl2 solution should be separated from rhodium, zinc, and copper. According to the data in **Figure 4**, the purity of the obtained radio-palladium is about 99%. Thereafter, the obtained filtrate solution was loaded onto the column of size Ø 0.5 cm × 2 cm packed with Amberlite®IR-93 resin with 0.6 mm diameter. The summarized results in **Figure 5** show that 0.05 M HCl is the most suitable concentration

The dosimetric parameters of the seeds have been determined by theoretical calculation and experimental measurement, according to TG-43 U1 report. The theoretical method to obtain the dosimetric parameters of the brachytherapy seeds

The following is the method to determine the dosimetric parameters by experi-

The TLD-GR200A (PTW, Freiburg, Germany) circular chips [26] of the follow-

*DOI: http://dx.doi.org/10.5772/intechopen.92457*

• AC current density > 1.8 A cm<sup>2</sup>

for adsorption of 103Pd on the Amberlite®IR-93 resin.

has been discussed and explained in Refs. [6, 9].

ing specifications have been used in this study:

*HPGe spectrum of radiochemically separated 103Pd [10].*

• 12 N HCl solution

• Temperature: 75°C

mental measurements.

**3.3 Dosimetry method**

• 0.8 mm thickness

• 4.5 mm in diameter

*3.3.1 Thermoluminescent dosimeters*

#### *Production of the 103Pd via Cyclotron and Preparation of the Brachytherapy Seed DOI: http://dx.doi.org/10.5772/intechopen.92457*

the activity of 103Pd and the yield of production are 685 mCi and 8.44 MBq/lAh, respectively. After the proton bombardment, the dissolution process has been started.

The optimum conditions of the electro-dissolution are as follows:

• 12 N HCl solution

*Recent Techniques and Applications in Ionizing Radiation Research*

[30, 31] is presented in **Figure 3**.

and also experimental data.

**3.2 Production of 103Pd**

for the electrodeposition:

• pH = 2

the purpose.

• 4.8 g rhodium (as Rh2(SO4)3)

• 1% sulfamic acid (w/v)

• Temperature 40–60°C

• DC current density of 8.5 mA cm<sup>−</sup><sup>2</sup>

show that the maximum cross-section is 1158.795 mb (Ed = 13 MeV). Comparison between the calculated results of this study and the measured data obtained by

The obtained results from ALICE/ASH code are in good agreement with the measured data by Hermanne et al. up to 20 MeV, whereas TALYS-1.2 and EMPIRE (version 3.1 Rivoli) calculated results have lower values than ALICE/ASH results

To prepare the rhodium target for irradiation, via the electrodeposition process,

After the electrodeposition process, the adhesion quality of the rhodium layer on the target backing has been tested by the thermal shock. The thermal shock has been carried out by heating the target up to 500°C for 1 h (The temperature that the Rh layer experience during high current irradiation). Thereafter, the hot target is submerged in cold water in a temperature of about 15°C. Observation of neither crack formation nor peeling off of the rhodium layers indicated a good adhesion for

Afterward, the rhodium target was bombarded with 18 MeV protons at 200 μA beam current for 15 h (3000 μAh) [12]. At the end of the bombardment (EOB),

*Excitation function of 103Rh(d,2n)103Pd reaction by ALICE/91, ALICE/ASH and TALYS-1.2 codes, and* 

a thick layer of rhodium has been placed of the copper backing. According to Sadeghi et al. study [11, 12], the following conditions are the optimum conditions

**106**

**Figure 3.**

*experimental data [10].*


After the dissolution of the target from copper backing, the residual contains PdCl2, rhodium, zinc, and copper, so during the radiochemical separation phase, the PdCl2 solution should be separated from rhodium, zinc, and copper. According to the data in **Figure 4**, the purity of the obtained radio-palladium is about 99%. Thereafter, the obtained filtrate solution was loaded onto the column of size Ø 0.5 cm × 2 cm packed with Amberlite®IR-93 resin with 0.6 mm diameter. The summarized results in **Figure 5** show that 0.05 M HCl is the most suitable concentration for adsorption of 103Pd on the Amberlite®IR-93 resin.

The dosimetric parameters of the seeds have been determined by theoretical calculation and experimental measurement, according to TG-43 U1 report. The theoretical method to obtain the dosimetric parameters of the brachytherapy seeds has been discussed and explained in Refs. [6, 9].

The following is the method to determine the dosimetric parameters by experimental measurements.

#### **3.3 Dosimetry method**

#### *3.3.1 Thermoluminescent dosimeters*

The TLD-GR200A (PTW, Freiburg, Germany) circular chips [26] of the following specifications have been used in this study:


**Figure 4.** *HPGe spectrum of radiochemically separated 103Pd [10].*

#### **Figure 5.**

*Absorption profile of 103Pd, as a function of HCl concentration on Amberlite®IR-93 resin [10].*

For the TLD calibration, before each experimental measurement, the entire batch of TLDs is exposed to a calibrated Cobalt-60 standard beam. The variation of response of the TLDs to the same exposure is tracked by normalizing the individual TLD readings to the average value.

The irradiated TLDs (irradiated by the brachytherapy seed in the phantom) are read using a KFKI RMKI TLD reader (KFKI Research Institute of the Hungarian Academy of Sciences, Budapest, Hungary), and then they are annealed by heating at 240°C for 10 min followed by fast cooling. The responses of the TLD have to be corrected for background. This is done by subtracting the average response of background TLDs from the responses of all other TLDs in each measurement [25, 32].

#### *3.3.2 Phantoms*

To determine the dosimetric parameters of the seeds by experimental measurement, the phantom of Perspex slabs (**Figure 6**), by the following specification, has been used.


The design of the two phantoms to measure the radial dose and anisotropy functions are based on those of [25].

**Figure 7** shows the phantom slab which is used for the experimental measurements of the brachytherapy seed radial dose function values. As shown in **Figure 7**, in the central phantom slaps, the holes are drilled to place the TLD circular chips. The circular surface of the TLDs is parallel to the seed long axis and is perpendicular to the slab plane [33, 34].

The measurements are carried out at distances of r = 0.5, 1, 1.5, 2, 3, 4, and 5 cm relative to the seed center. To minimize the interference of any of TLDs with regard to the response by other TLD chips, the measurement is performed in a spiral configuration [6, 8, 35, 36].

**109**

repeated several times.

**Figure 6.**

**Figure 7.**

*Perspex phantom slabs.*

*Production of the 103Pd via Cyclotron and Preparation of the Brachytherapy Seed*

In this study, 28 TLDs (4 at each radial distance) were used for every single experiment to prevent the shadowing effect due to the configuration and the design of the phantom. To improve the statistical quality of the data, the experiment was

*Central slabs of Perspex phantoms used for the experimental determination of radial dose function values.*

The other phantom is shown in **Figure 8**. This phantom has been used for the measurement of the anisotropy function of the brachytherapy seed. It has the same dimensions as the first phantom but differs in the configuration of the source in that. The source is placed parallel to the central slab plane with its long axis.

The TLDs are placed at radial distances of r = 1.5, 2, 3, and 5 cm relative to the seed center and also lie at the polar angles θ ranging from 0 to 330° in 30° increments with respect to the seed long axis. The measurements were performed with 48 holes containing TLDs since it was found that for the experimental anisotropy function determination at a specific point, shadowing effects due to the TLDs that lie at the same polar angle do not affect results. This is due to the definition of anisotropy

*DOI: http://dx.doi.org/10.5772/intechopen.92457*

*Production of the 103Pd via Cyclotron and Preparation of the Brachytherapy Seed DOI: http://dx.doi.org/10.5772/intechopen.92457*

**Figure 6.** *Perspex phantom slabs.*

*Recent Techniques and Applications in Ionizing Radiation Research*

TLD readings to the average value.

• Dimension: 30 cm × 30 cm × 15 cm

• Density: 1.19 g/cm3

tions are based on those of [25].

lar to the slab plane [33, 34].

configuration [6, 8, 35, 36].

*3.3.2 Phantoms*

**Figure 5.**

been used.

For the TLD calibration, before each experimental measurement, the entire batch of TLDs is exposed to a calibrated Cobalt-60 standard beam. The variation of response of the TLDs to the same exposure is tracked by normalizing the individual

*Absorption profile of 103Pd, as a function of HCl concentration on Amberlite®IR-93 resin [10].*

The irradiated TLDs (irradiated by the brachytherapy seed in the phantom) are read using a KFKI RMKI TLD reader (KFKI Research Institute of the Hungarian Academy of Sciences, Budapest, Hungary), and then they are annealed by heating at 240°C for 10 min followed by fast cooling. The responses of the TLD have to be corrected for background. This is done by subtracting the average response of background TLDs from the responses of all other TLDs in each measurement [25, 32].

To determine the dosimetric parameters of the seeds by experimental measurement, the phantom of Perspex slabs (**Figure 6**), by the following specification, has

The design of the two phantoms to measure the radial dose and anisotropy func-

**Figure 7** shows the phantom slab which is used for the experimental measurements of the brachytherapy seed radial dose function values. As shown in **Figure 7**, in the central phantom slaps, the holes are drilled to place the TLD circular chips. The circular surface of the TLDs is parallel to the seed long axis and is perpendicu-

The measurements are carried out at distances of r = 0.5, 1, 1.5, 2, 3, 4, and 5 cm relative to the seed center. To minimize the interference of any of TLDs with regard to the response by other TLD chips, the measurement is performed in a spiral

• Composition (by weight percent): H, 8%; C, 60%; and O, 32%

**108**

**Figure 7.** *Central slabs of Perspex phantoms used for the experimental determination of radial dose function values.*

In this study, 28 TLDs (4 at each radial distance) were used for every single experiment to prevent the shadowing effect due to the configuration and the design of the phantom. To improve the statistical quality of the data, the experiment was repeated several times.

The other phantom is shown in **Figure 8**. This phantom has been used for the measurement of the anisotropy function of the brachytherapy seed. It has the same dimensions as the first phantom but differs in the configuration of the source in that. The source is placed parallel to the central slab plane with its long axis.

The TLDs are placed at radial distances of r = 1.5, 2, 3, and 5 cm relative to the seed center and also lie at the polar angles θ ranging from 0 to 330° in 30° increments with respect to the seed long axis. The measurements were performed with 48 holes containing TLDs since it was found that for the experimental anisotropy function determination at a specific point, shadowing effects due to the TLDs that lie at the same polar angle do not affect results. This is due to the definition of anisotropy

**Figure 8.** *Central slabs of Perspex phantoms used for the experimental determination of anisotropy function values.*

function that normalizes dose rate at a particular (r, θ) point to the dose rate at the corresponding point along the transverse source bisector, (r, 90°). Therefore, since shadowing was found similar at any polar angle for the same radial distance, the overall effect is canceled out in the calculation of an anisotropy function [12].

#### **4. Conclusion**

This chapter presents the application of the cyclotron in brachytherapy by the production of radioisotopes such as Palladium-103.

In this chapter, production of the 103Pd via cyclotron has been presented. **103Pd** is used in permanent low-dose radiation brachytherapy. So preparation of the brachytherapy source having 103Pd radioisotope has also been discussed.

103Pd production is performed via the 103Rh(p,n)103Pd reaction by 18 MeV protons for 15 h at 200 μA beam current. The optimum energy range and the thickness of the rhodium target are calculated by the several computer codes (ALIS/ ASH, TALYS, EMPIRE). Several codes have been used to increase the accuracy of the calculations. To use the 103Pd as brachytherapy source, the resin beads which are loaded by 103Pd are encapsulated inside the titanium capsule, and then the capsules are implanted into the cancerous area. So, after the chemical separation process, 103Pd radioisotope is absorbed uniformly in the resin Amberlite®IR-93, (20–50 mesh) bead to encapsulate them inside the titanium casing.

According to the American Association of Physicists in Medicine (AAPM) Radiation Therapy Committee recommendation, the dosimetric parameters of all new interstitial brachytherapy sources with energies less than 50 keV should be determined by two independent verifications, experimental measurements and theoretical calculations. The method for the theoretical calculation of the brachytherapy seed has been previously explained in Refs. [6, 9]. In this study, the experimental measurement method, the design, and dimension of the phantom and configuration of the TLDs have also been explained.

**111**

**Author details**

Sciences, Tehran, Iran

\* and Mahdi Sadeghi<sup>2</sup>

\*Address all correspondence to: poonehsaidi@gmail.com

provided the original work is properly cited.

1 Parsikan Iran Engineering and Management Consultants, Tehran, Iran

2 Medical Physics Department, School of Medicine, Iran University of Medical

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

Pooneh Saidi1

*Production of the 103Pd via Cyclotron and Preparation of the Brachytherapy Seed*

*DOI: http://dx.doi.org/10.5772/intechopen.92457*

*Production of the 103Pd via Cyclotron and Preparation of the Brachytherapy Seed DOI: http://dx.doi.org/10.5772/intechopen.92457*

### **Author details**

*Recent Techniques and Applications in Ionizing Radiation Research*

function that normalizes dose rate at a particular (r, θ) point to the dose rate at the corresponding point along the transverse source bisector, (r, 90°). Therefore, since shadowing was found similar at any polar angle for the same radial distance, the overall effect is canceled out in the calculation of an anisotropy function [12].

*Central slabs of Perspex phantoms used for the experimental determination of anisotropy function values.*

This chapter presents the application of the cyclotron in brachytherapy by the

In this chapter, production of the 103Pd via cyclotron has been presented. **103Pd**

is used in permanent low-dose radiation brachytherapy. So preparation of the brachytherapy source having 103Pd radioisotope has also been discussed.

103Pd production is performed via the 103Rh(p,n)103Pd reaction by 18 MeV protons for 15 h at 200 μA beam current. The optimum energy range and the thickness of the rhodium target are calculated by the several computer codes (ALIS/ ASH, TALYS, EMPIRE). Several codes have been used to increase the accuracy of the calculations. To use the 103Pd as brachytherapy source, the resin beads which are loaded by 103Pd are encapsulated inside the titanium capsule, and then the capsules are implanted into the cancerous area. So, after the chemical separation process, 103Pd radioisotope is absorbed uniformly in the resin Amberlite®IR-93, (20–50

According to the American Association of Physicists in Medicine (AAPM) Radiation Therapy Committee recommendation, the dosimetric parameters of all new interstitial brachytherapy sources with energies less than 50 keV should be determined by two independent verifications, experimental measurements and theoretical calculations. The method for the theoretical calculation of the brachytherapy seed has been previously explained in Refs. [6, 9]. In this study, the experimental measurement method, the design, and dimension of the phantom and

production of radioisotopes such as Palladium-103.

mesh) bead to encapsulate them inside the titanium casing.

configuration of the TLDs have also been explained.

**110**

**4. Conclusion**

**Figure 8.**

Pooneh Saidi1 \* and Mahdi Sadeghi<sup>2</sup>

1 Parsikan Iran Engineering and Management Consultants, Tehran, Iran

2 Medical Physics Department, School of Medicine, Iran University of Medical Sciences, Tehran, Iran

\*Address all correspondence to: poonehsaidi@gmail.com

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

### **References**

[1] Khan F. Handbook of the Physics of Radiation Therapy. Baltimore: Williams and Wilkins; 2009. pp. 36-53

[2] Schlyer DJ, Van den Winkel P, Ruth TJ, Vora MM. Cyclotron produced radionuclides: Principles and practice. In: Technical Reports Series No. 465. Vienna: IAEA; 2008. pp. 31-57

[3] Simone Manenti S, del Carmen M, Santoro A, Cotogno G, Duchemin C, Haddad F, et al. Excitation function and yield for the 103Rh(d,2n)103Pd nuclear reaction: Optimization of the production of palladium-103. Nuclear Medicine and Biology. 2017;**49**:30-37

[4] Baltas D, Sakelliou L, Zamboglou N. The Physics of Modern Brachytherapy for Oncology. New York: Taylor & Francis Group; 2007. p. 165

[5] Sadeghi M, Enferadi M, Shirazi A. External and internal radiation therapy: Past and future directions. Journal of Cancer Research and Therapeutics. 2010;**6**:239-248

[6] Saidi P, Sadeghi M, Tenreiro C. Theory and applications of Monte Carlo simulations. In: Chan VWK, editor. Variance Reduction of Monte Carlo Simulation in Nuclear Engineering Field, Ch. 7. London: Intech; 2013. pp. 153-172. DOI: 10.5772/53384

[7] Saidi P, Sadeghi M, Shirazi A, Tenreiro C. Monte Carlo calculation of dosimetry parameters for the IR08- 103Pd brachytherapy source. Medical Physics. 2010;**37**:2509-2515. DOI: 10.1118/1.3416922

[8] Saidi P, Sadeghi M, Tenreiro C. Experimental measurements and Monte Carlo calculations for 103Pd dosimetry of the 12 mm COMS eye plaque. Physica Medica. 2013;**29**:286-294. DOI: 10.1016/j.ejmp.2012.04.002

[9] Sadeghi M, Saidi P, Tenreiro C. Dosimetric characteristics of the brachytherapy sources based on Monte Carlo method. In: Mode CJ, editor. Applications of Monte Carlo Methods in Biology, Medicine and Other Fields of Science, Ch. 10. London: Intech; 2011. pp. 155-176. DOI: 10.5772/15884

[10] Saidi P, Sadeghi M, Enferadi M, Aslani G. Investigation of palladium-103 production and IR07-103Pd brachytherapy seed preparation. Annals of Nuclear Energy. 2011;**38**:2168-2173

[11] Sadeghi M, Shirazi B. Extraction separation of no carrier- added 103Pd from irradiated Rh target, Cu and Zn using α-furyldioxime, dimethylglyoxime and αbenzildioxime. Applied Radiation and Isotopes. 2008;**66**:1810-1813

[12] Sadeghi M, Shirazi B, Shadanpour N. Solvent extraction of no-carrier-added 103-Pd from irradiated rhodium target with α-furyldioxime. Journal of Radioanalytical and Nuclear Chemistry. 2006;**269**:223-225

[13] Broeders CHM, Konobeyev A, Kocrovin YA, Blann VPM. Precompound and Evaporation Model Code System for Calculation of Excitation Functions, Energy and Angular Distributions of Emitted Particles in Nuclear Reactions at Intermediate Energies. Frschungszentrum Karlsruhe Report FZKA. Hannover; 2006. p. 7183

[14] Koning AJ, Hilaire S, Duijvestijn M. TALYS-1.2: A Nuclear Reaction Program, User Manual. Netherlands: NRG; 2009

[15] EXFOR/CSISRS. 2011. Experimental Nuclear Reaction Data. Available from: http://wwwnds.iaea.org/exfor

[16] Koning AJ, Rochman D. TENDL-2010: TALYS-Based Evaluated Nuclear

**113**

*Production of the 103Pd via Cyclotron and Preparation of the Brachytherapy Seed*

approximations. Nukleonika.

Determination of dosimetry parameters of ADVANTAGETM 103Pd brachytherapy seed using MCNP4C computer code. Nukleonika.

10.1120/jacmp.v12i4.3581

Review. 1962;**128**:291-299

2000;**B170**:281-292

[24] Ataeinia V, Raisali G, Sadeghi M.

[25] Saidi P, Sadeghi M, Hosseini SH. Thermoluminescent dosimetry of the IR06-103Pd brachytherapy source. Journal of Applied Clinical Medical Physics. 2011;**12**(4):286-295. DOI:

[26] Harper PV, Lathrop K, Need JL. The thick target yield and excitation function for the reaction 103Rh(p,n)103Pd. Nuclear Science. 1961;**15**:124

[27] Hansen LF, Albert RD. Statistical theory predictions for 5 to 11 MeV (p,n) and (p,p') nuclear reactions in 51V, 59Co, 63Cu, 65Cu, and 103Rh. Physics

[28] Hermanne A, Sonck M, Fenyvesi A,

Daraban L. Study of production of 103Pd and characterisation of possible contaminants in the proton irradiation of 103Rh up to 28 MeV. Nuclear Instruments & Methods.

[29] Sudar S, Cserpak F, Qaim SM. Measurements and nuclear model calculations on proton-induced reactions on Rh-103 up to 40-MeVevaluation of the excitation function of the Rh-103(p,n)Pd-103 reaction relevant to the production of the therapeutic radionuclide Pd-103. Applied Radiation

and Isotopes. 2002;**56**:821-831

2009;**67**:1574-1581

[30] Tárkányi F, Hermanne A, Király B, Takacs S, Ditrói F, Csikai J, et al. New cross-sections for production of 103Pd; review of charged particle production routes. Applied Radiation and Isotopes.

2008;**53**:45-49

2009;**54**:181-187

*DOI: http://dx.doi.org/10.5772/intechopen.92457*

Data Library. The Netherlands: Nuclear Research and Consultancy Group (NRG) Petten; 2010. Available from: http://www.talys.eu/tendl-2010

[17] Saidi Bidokhti P, Sadeghi M, Fateh B, Matloobi M, Aslani G. Nuclear data measurement of 186-Re production via various reactions. Nuclear Engineering and Technology.

[18] Sadeghi M, Enferadi M. Nuclear model calculations on the production

reactions. Annals of Nuclear Energy.

[19] Büyükuslu H, Kaplan A, Tel E, Aydin A, Yildırım G, Bolukdemir MH. Theoretical cross-sections of 209Bi, 232Th, 235U, and 238U on deuteroninduced reactions. Annals of Nuclear

[20] Herman M, Capote R, Zerkin V, Trkov A, Wienke H, Sin M, et al. EMPIRE Modular System for Nuclear Reaction Calculations (version: 3.1 Rivoli). 2011. Available from: https:// ndclx4.bnl.gov/gf/project/empire/

[21] Ziegler JF, Biersack JP, Littmark U. The Code of SRIM, the Stopping and Range of Ion in Matter. New York, USA:

[22] Saidi P, Sadeghi M. Theory, application and implementation of Monte Carlo method in science and technology. In: Bidokhti PS, editor. Modeling, Simulation, and Dosimetry of 103-Pd Eye Plaque Brachytherapy, Ch. 2. London: Intech; 2019. pp. 19-38.

DOI: 10.5772/intechopen.78141

of the geometry function for a

[23] Raisali G, Ghonchehnazi MG, Shokrani P, Sadeghi M. Determination

brachytherapy seed, comparing MCNP results with TG-43U1 analytical

of 119Sb via various nuclear

Energy. 2010;**37**:534-539

IBM-Research; 2006

2010;**42**(5):600-607

2011;**38**:825-834

*Production of the 103Pd via Cyclotron and Preparation of the Brachytherapy Seed DOI: http://dx.doi.org/10.5772/intechopen.92457*

Data Library. The Netherlands: Nuclear Research and Consultancy Group (NRG) Petten; 2010. Available from: http://www.talys.eu/tendl-2010

[17] Saidi Bidokhti P, Sadeghi M, Fateh B, Matloobi M, Aslani G. Nuclear data measurement of 186-Re production via various reactions. Nuclear Engineering and Technology. 2010;**42**(5):600-607

[18] Sadeghi M, Enferadi M. Nuclear model calculations on the production of 119Sb via various nuclear reactions. Annals of Nuclear Energy. 2011;**38**:825-834

[19] Büyükuslu H, Kaplan A, Tel E, Aydin A, Yildırım G, Bolukdemir MH. Theoretical cross-sections of 209Bi, 232Th, 235U, and 238U on deuteroninduced reactions. Annals of Nuclear Energy. 2010;**37**:534-539

[20] Herman M, Capote R, Zerkin V, Trkov A, Wienke H, Sin M, et al. EMPIRE Modular System for Nuclear Reaction Calculations (version: 3.1 Rivoli). 2011. Available from: https:// ndclx4.bnl.gov/gf/project/empire/

[21] Ziegler JF, Biersack JP, Littmark U. The Code of SRIM, the Stopping and Range of Ion in Matter. New York, USA: IBM-Research; 2006

[22] Saidi P, Sadeghi M. Theory, application and implementation of Monte Carlo method in science and technology. In: Bidokhti PS, editor. Modeling, Simulation, and Dosimetry of 103-Pd Eye Plaque Brachytherapy, Ch. 2. London: Intech; 2019. pp. 19-38. DOI: 10.5772/intechopen.78141

[23] Raisali G, Ghonchehnazi MG, Shokrani P, Sadeghi M. Determination of the geometry function for a brachytherapy seed, comparing MCNP results with TG-43U1 analytical

approximations. Nukleonika. 2008;**53**:45-49

[24] Ataeinia V, Raisali G, Sadeghi M. Determination of dosimetry parameters of ADVANTAGETM 103Pd brachytherapy seed using MCNP4C computer code. Nukleonika. 2009;**54**:181-187

[25] Saidi P, Sadeghi M, Hosseini SH. Thermoluminescent dosimetry of the IR06-103Pd brachytherapy source. Journal of Applied Clinical Medical Physics. 2011;**12**(4):286-295. DOI: 10.1120/jacmp.v12i4.3581

[26] Harper PV, Lathrop K, Need JL. The thick target yield and excitation function for the reaction 103Rh(p,n)103Pd. Nuclear Science. 1961;**15**:124

[27] Hansen LF, Albert RD. Statistical theory predictions for 5 to 11 MeV (p,n) and (p,p') nuclear reactions in 51V, 59Co, 63Cu, 65Cu, and 103Rh. Physics Review. 1962;**128**:291-299

[28] Hermanne A, Sonck M, Fenyvesi A, Daraban L. Study of production of 103Pd and characterisation of possible contaminants in the proton irradiation of 103Rh up to 28 MeV. Nuclear Instruments & Methods. 2000;**B170**:281-292

[29] Sudar S, Cserpak F, Qaim SM. Measurements and nuclear model calculations on proton-induced reactions on Rh-103 up to 40-MeVevaluation of the excitation function of the Rh-103(p,n)Pd-103 reaction relevant to the production of the therapeutic radionuclide Pd-103. Applied Radiation and Isotopes. 2002;**56**:821-831

[30] Tárkányi F, Hermanne A, Király B, Takacs S, Ditrói F, Csikai J, et al. New cross-sections for production of 103Pd; review of charged particle production routes. Applied Radiation and Isotopes. 2009;**67**:1574-1581

**112**

*Recent Techniques and Applications in Ionizing Radiation Research*

[9] Sadeghi M, Saidi P, Tenreiro C. Dosimetric characteristics of the brachytherapy sources based on Monte Carlo method. In: Mode CJ, editor. Applications of Monte Carlo Methods in Biology, Medicine and Other Fields of Science, Ch. 10. London: Intech; 2011. pp. 155-176. DOI: 10.5772/15884

[10] Saidi P, Sadeghi M, Enferadi M, Aslani G. Investigation of palladium-103 production and IR07-103Pd brachytherapy seed preparation. Annals of Nuclear Energy. 2011;**38**:2168-2173

[11] Sadeghi M, Shirazi B. Extraction separation of no carrier- added 103Pd from irradiated Rh target, Cu and Zn using α-furyldioxime,

benzildioxime. Applied Radiation and

Shadanpour N. Solvent extraction of no-carrier-added 103-Pd from irradiated rhodium target with α-furyldioxime. Journal of Radioanalytical and Nuclear

dimethylglyoxime and α-

Isotopes. 2008;**66**:1810-1813

Chemistry. 2006;**269**:223-225

[13] Broeders CHM, Konobeyev A, Kocrovin YA, Blann VPM. Pre-

compound and Evaporation Model Code System for Calculation of Excitation Functions, Energy and Angular Distributions of Emitted Particles in Nuclear Reactions at Intermediate Energies. Frschungszentrum Karlsruhe Report FZKA. Hannover; 2006. p. 7183

[14] Koning AJ, Hilaire S, Duijvestijn M.

[15] EXFOR/CSISRS. 2011. Experimental Nuclear Reaction Data. Available from:

[16] Koning AJ, Rochman D. TENDL-2010: TALYS-Based Evaluated Nuclear

TALYS-1.2: A Nuclear Reaction Program, User Manual. Netherlands:

http://wwwnds.iaea.org/exfor

NRG; 2009

[12] Sadeghi M, Shirazi B,

[1] Khan F. Handbook of the Physics of Radiation Therapy. Baltimore: Williams

and Wilkins; 2009. pp. 36-53

**References**

[2] Schlyer DJ, Van den Winkel P, Ruth TJ, Vora MM. Cyclotron produced radionuclides: Principles and practice. In: Technical Reports Series No. 465. Vienna: IAEA; 2008. pp. 31-57

[3] Simone Manenti S, del Carmen M, Santoro A, Cotogno G, Duchemin C, Haddad F, et al. Excitation function and yield for the 103Rh(d,2n)103Pd nuclear reaction: Optimization of the production of palladium-103. Nuclear Medicine and Biology. 2017;**49**:30-37

[4] Baltas D, Sakelliou L, Zamboglou N. The Physics of Modern Brachytherapy for Oncology. New York: Taylor & Francis Group; 2007. p. 165

[5] Sadeghi M, Enferadi M, Shirazi A. External and internal radiation therapy: Past and future directions. Journal of Cancer Research and Therapeutics.

[6] Saidi P, Sadeghi M, Tenreiro C. Theory and applications of Monte Carlo simulations. In: Chan VWK, editor. Variance Reduction of Monte Carlo Simulation in Nuclear Engineering Field, Ch. 7. London: Intech; 2013. pp. 153-172. DOI: 10.5772/53384

[7] Saidi P, Sadeghi M, Shirazi A, Tenreiro C. Monte Carlo calculation of dosimetry parameters for the IR08- 103Pd brachytherapy source. Medical Physics. 2010;**37**:2509-2515. DOI:

[8] Saidi P, Sadeghi M, Tenreiro C. Experimental measurements and Monte Carlo calculations for 103Pd dosimetry of the 12 mm COMS eye plaque. Physica Medica. 2013;**29**:286-294. DOI:

10.1016/j.ejmp.2012.04.002

2010;**6**:239-248

10.1118/1.3416922

[31] Hermanne A, Sonck M, Takacs S, Tárkányi F, Shubin FY. Study on alternative production of 103Pd and characterisation of contaminant sin the deuteron irradiation of 103Rh up to 21 MeV. Nuclear Instruments & Methods. 2002;**B187**:3-14

[32] Duggan L, Hood C, Warren-Forward H, Haque M, Kron T. Variation in dose response with X-ray energy of LiF:Mg, Cu, P thermoluminescence dosimeters: Implications for clinical dosimetry. Physics in Medicine and Biology. 2004;**49**(18):3831-3845

[33] Meigooni AS, Gearheart DM, Sowards K. Experimental determination of dosimetric characteristics of bests 125I brachytherapy source. Medical Physics. 2000;**27**(9):2168-2173

[34] Meigooni AS, Sowards K, Soldano M. Dosimetric characteristics of the intersource 103-palladium brachytherapy source. Medical Physics. 2000;**27**(5):1093-1099

[35] Hosseini SH, Sadeghi M, Ataeinia V. Dosimetric comparison of four new designs 103-Pd brachytherapy sources: Optimal design using silver and copper rod cores. Medical Physics. 2009;**36**(7):3080-3085

[36] Sadeghi M, Hosseini SH, Raisali G. Experimental measurements and Monte Carlo calculations of dosimetric parameters of the IRA1-103Pd brachytherapy source. Applied Radiation and Isotopes. 2008;**66**(10):1431-1437

**115**

**Chapter 8**

**Abstract**

agents

**1. Introduction**

Bisphosphonates as Chelating

Agents in Uranium Poisoning

The study of uranium toxicity is very important for public health in general and especially for workers involved in the processes of uranium mining and milling because of the immediate and/or mediate risks of exposure. Most available studies show unsuccessful attempts to eliminate uranium from target organs once the poisoning has occurred. Our group has managed to avoid damage to target organs (short-term kidney and long-term bone damage) in a high percentage of animals treated with lethal doses of uranyl nitrate through the effective chelating action of a single dose of bisodic etidronate. In this context, the contributions of our team and other groups working on chelating therapies provide a starting point for progress in the search for agents for preventing and/or reducing the toxic effects of uranium.

**Keywords:** uranium, poisoning, bisphosphonates, bisodic etidronate, chelating

with good quality of life, similar to that of controls.

As from the World War II, increasing interest in nuclear power brought about an increase in uranium exploration and the development of new plants for uranium processing and manufacture in many countries. These activities may involve accidental occupational poisoning for workers, and no protocol has yet been designed for rapid application in these cases to prevent rapid-onset life-threatening complications due to kidney failure. As the uranium-related industry increases, so does the potential for these accidental poisonings. In this chapter we present and discuss the papers published by our laboratory over almost 40 years of research in the field of the toxicology of uranium in animal models under the direction of Dr. Romulo Luis Cabrini, which replicated hypothetical situations of acute accidental exposure to uranium via different routes of entry. Our group has specifically studied toxicity on target organs (kidneys and bone) and developed a potentially effective protocol with bisodic etidronate used as a chelating agent that prevents kidney failure and bone alterations. We are currently processing histological and histomorphometrical kidney and bone samples from a long-term experiment with animals poisoned with lethal doses of uranyl nitrate and treated with a single subcutaneous dose of bisodic etidronate which survived for 1 year after treatment

*Adriana Beatriz Martínez, Carola Bettina Bozal,* 

*Nadia Soledad Orona, Deborah Ruth Tasat* 

*and Angela Matilde Ubios*

#### **Chapter 8**

*Recent Techniques and Applications in Ionizing Radiation Research*

[31] Hermanne A, Sonck M, Takacs S, Tárkányi F, Shubin FY. Study on alternative production of 103Pd and characterisation of contaminant sin the deuteron irradiation of 103Rh up to 21 MeV. Nuclear Instruments &

Methods. 2002;**B187**:3-14

[32] Duggan L, Hood C, Warren-

[33] Meigooni AS, Gearheart DM, Sowards K. Experimental determination of dosimetric characteristics of bests 125I brachytherapy source. Medical Physics. 2000;**27**(9):2168-2173

[34] Meigooni AS, Sowards K,

2000;**27**(5):1093-1099

2009;**36**(7):3080-3085

2008;**66**(10):1431-1437

Experimental measurements and Monte Carlo calculations of dosimetric parameters of the IRA1-103Pd brachytherapy source. Applied Radiation and Isotopes.

Soldano M. Dosimetric characteristics of the intersource 103-palladium brachytherapy source. Medical Physics.

[35] Hosseini SH, Sadeghi M, Ataeinia V. Dosimetric comparison of four new designs 103-Pd brachytherapy sources: Optimal design using silver and copper rod cores. Medical Physics.

[36] Sadeghi M, Hosseini SH, Raisali G.

Forward H, Haque M, Kron T. Variation in dose response with X-ray energy of LiF:Mg, Cu, P thermoluminescence dosimeters: Implications for clinical dosimetry. Physics in Medicine and Biology. 2004;**49**(18):3831-3845

**114**

## Bisphosphonates as Chelating Agents in Uranium Poisoning

*Adriana Beatriz Martínez, Carola Bettina Bozal, Nadia Soledad Orona, Deborah Ruth Tasat and Angela Matilde Ubios*

#### **Abstract**

The study of uranium toxicity is very important for public health in general and especially for workers involved in the processes of uranium mining and milling because of the immediate and/or mediate risks of exposure. Most available studies show unsuccessful attempts to eliminate uranium from target organs once the poisoning has occurred. Our group has managed to avoid damage to target organs (short-term kidney and long-term bone damage) in a high percentage of animals treated with lethal doses of uranyl nitrate through the effective chelating action of a single dose of bisodic etidronate. In this context, the contributions of our team and other groups working on chelating therapies provide a starting point for progress in the search for agents for preventing and/or reducing the toxic effects of uranium.

**Keywords:** uranium, poisoning, bisphosphonates, bisodic etidronate, chelating agents

#### **1. Introduction**

As from the World War II, increasing interest in nuclear power brought about an increase in uranium exploration and the development of new plants for uranium processing and manufacture in many countries. These activities may involve accidental occupational poisoning for workers, and no protocol has yet been designed for rapid application in these cases to prevent rapid-onset life-threatening complications due to kidney failure. As the uranium-related industry increases, so does the potential for these accidental poisonings. In this chapter we present and discuss the papers published by our laboratory over almost 40 years of research in the field of the toxicology of uranium in animal models under the direction of Dr. Romulo Luis Cabrini, which replicated hypothetical situations of acute accidental exposure to uranium via different routes of entry. Our group has specifically studied toxicity on target organs (kidneys and bone) and developed a potentially effective protocol with bisodic etidronate used as a chelating agent that prevents kidney failure and bone alterations. We are currently processing histological and histomorphometrical kidney and bone samples from a long-term experiment with animals poisoned with lethal doses of uranyl nitrate and treated with a single subcutaneous dose of bisodic etidronate which survived for 1 year after treatment with good quality of life, similar to that of controls.

#### **2. Biological impact of uranium: pharmacokinetics**

Because uranium (U) is present in food, air, soil, and water, humans are constantly exposed to certain amounts of this element. Notwithstanding, the biological impact of such natural exposure on human physiology and pathophysiology is not yet fully known. However, it is known that overexposure to U may result in toxicity, which is derived from an excessive accumulation of the element in the organism. This accumulation depends on various factors, including route of entry, duration of exposure, dose, chemical compound of which it forms part, and absorption [1, 2].

Uranium can enter the body through different routes: oral, inhalation, percutaneous, or subcutaneous. Regardless of the route of entry, absorbed U enters systemic circulation, is distributed in the organism, and accumulates mainly in the bones (66%), kidneys (8%), and liver (16%) [3]. Approximately 1–5% of an oral dose is absorbed in the digestive tract [4], and nearly 60% of U is eliminated rapidly from the blood and slowly from organ depots with the urine by renal mechanisms in the first 24 h [5, 6]. In rats, most of the absorbed U is eliminated by the kidneys in a few days; half of it is excreted within 2–6 days [7] and the rest within 7 days. Ninety-five percent (95%) of U present in the kidneys of intoxicated rats is excreted in the urine within a week, and very small amounts remain in other organs [6, 8]. Uranium compounds can dissociate and form new compounds with various organic and inorganic anions. In body fluids, tetravalent uranium (+4) tends to oxidize to the hexavalent form (+6) followed by uranyl ion formation. Experimentally, using animal models, it was shown that uranyl ions are associated with ultrafiltered low molecular weight serum proteins, transferrin, and other plasma proteins [3]. In 2005, Vidaud *et al*. [9] were able to identify uranium-binding proteins in human serum fractions by means of an in vitro-sensitive procedure involving a combination of bidimensional chromatography with time-resolved fluorescence, coupled with proteomic analysis. These authors demonstrated that not all targets are metalloproteins, suggesting that uranyl ions can use a wide variety of binding sites, thus providing additional insights for a better understanding of uranium chemical toxicity. U also binds to phospholipids and membrane proteins of proximal contoured tubules [10].

On the other hand, when injected intravenously, almost 50% of the U is eliminated, while the other 50% is deposited in the skeleton (25%) and in soft tissues (25%), mainly kidneys. The U deposited in extrarenal soft tissues—mainly liver and spleen—is removed very slowly [11]. Orcutt *et al*. [12] reported that the percutaneous route constitutes an effective route of entry for soluble U compounds. De Rey *et al*. [13] demonstrated that uranyl nitrate (UN) can penetrate through the skin of adult Wistar rats in approximately 15 min and accumulate in the intercellular spaces between the granular and corneal layers. After 48 h, the U was not found in the skin, and the animals experienced signs of severe toxicity ranging from weight loss to death, clearly indicating its passage from this organ into the circulation. The retention of U particles after inhalation depends on the size of the particulate and the type of U compound. Harris *et al*. [14] reported that insoluble compounds (uranium dioxide and uranium trioxide) with average particle size below 2 μm have very long biological half-lives (120 days or more).

Uranium impact on human health may come from abandoned hard rock mines, which can contaminate the three natural resources—water, air, and soil—thus becoming a potential source of chronic exposure and toxicity for individuals living in the area.

It is worth noting that U toxicity depends on several factors, such as sex, age, body mass index [15], and species. Of all the mammals studied, humans seem to be the least sensitive to U [16]. Still, overexposure to U may cause pathological alterations in the different organs in both humans and animals.

**117**

*Bisphosphonates as Chelating Agents in Uranium Poisoning*

compound than if the rats had not been subjected to fasting.

The oral route is important because of the possibility of the general population having to ingest U-contaminated water or food continuously, as well as the risk of workers ingesting toxic and/or lethal doses during accidents in some of the steps of the enrichment process. The literature contains interesting—though limited—data on the incorporation of U via the oral route, obtained from studies in both experi-

Harrison *et al*. [17] studied the gastrointestinal absorption of two U compounds administered orally by gastric intubation (gavage) in hamsters and demonstrated that soluble UN absorption was seven times greater than insoluble uranium dioxide

La Touche *et al*. [6] investigated the absorption and kinetics of UN administered orally in a model with fasting adult male Wistar rats that replicate the human intake of contaminated water after a night of fasting. It produced more absorption of the

Anke *et al*. [18] studied wild plants and cultivated plants from the immediate vicinity of uranium waste dumps and found that they stored up to eightfold higher

In 2013, the ATSDR (US Agency for Toxic Substances and Disease Registry) [1] established a minimum risk level for the ingestion of U, known by the acronym MRL (minimum risk level), which is 0.002 μg of U per kilo of weight per day. The MRL is an estimate of the daily exposure of a human being to a dangerous substance that probably does not represent an appreciable risk of adverse effects (excluding cancer) beyond the time of exposure. MRL values for both oral and inhalation routes vary with different exposure times: acute (1–14 days), intermediate

Zamora *et al*. [19] studied the effects of chronic ingestion of U in humans after drinking contaminated water. They suggested that intake of U doses such as those found in some underground water wells over prolonged periods of time altered the renal function. These observed effects may represent a manifestation of subclinical toxicity that does not necessarily lead to renal dysfunction or obvious injury. Instead, it may be the first stage in a spectrum in which chronic intake of elevated U

In addition to being ingested via drinking water, U can be taken in orally through

The concentrations of U in fish muscle (per gram of dry weight) extracted from a Canadian lake contaminated by tributaries of a U processing plant were 7–11 times higher than in those from uncontaminated lakes [21]. Lapham *et al*. [22] analyzed U concentrations in cattle muscle and found that although U levels in the muscle of the exposed cattle were almost imperceptible with respect to the controls, U concentration in the liver and renal tissues was 4 times higher in the exposed cattle than in the control. Moreover, U levels in the bone (femur samples) were found to

Other than beef and fish, some underground vegetables such as potatoes, sweet potatoes, and turnips contribute approximately 38% of the U intake per diet

Although there are no studies in humans regarding the lethal effects of U and its compounds when ingested orally, several animal studies have shown that a very high intake dose of U can be lethal for acute (1–14 days), subacute (14–365 days),

Maynard and Hodge [1] obtained an LD50 (lethal dose 50 population %) value for oral (UN) of 1579 mg of U/kg/day in rats of both sexes (without specifying

*DOI: http://dx.doi.org/10.5772/intechopen.92220*

mental animals and humans.

uranium concentrations than controls.

(15–365 days), and chronic (365 days or longer).

levels can lead to irreversible renal injury [20].

contaminated food, mainly beef and fish.

be 13 times higher than in the controls.

according to the general food consumption rate [23].

and chronic (more than 365 days) exposures [24].

**2.1 Oral route**

(UD) absorption.

#### **2.1 Oral route**

The oral route is important because of the possibility of the general population having to ingest U-contaminated water or food continuously, as well as the risk of workers ingesting toxic and/or lethal doses during accidents in some of the steps of the enrichment process. The literature contains interesting—though limited—data on the incorporation of U via the oral route, obtained from studies in both experimental animals and humans.

Harrison *et al*. [17] studied the gastrointestinal absorption of two U compounds administered orally by gastric intubation (gavage) in hamsters and demonstrated that soluble UN absorption was seven times greater than insoluble uranium dioxide (UD) absorption.

La Touche *et al*. [6] investigated the absorption and kinetics of UN administered orally in a model with fasting adult male Wistar rats that replicate the human intake of contaminated water after a night of fasting. It produced more absorption of the compound than if the rats had not been subjected to fasting.

Anke *et al*. [18] studied wild plants and cultivated plants from the immediate vicinity of uranium waste dumps and found that they stored up to eightfold higher uranium concentrations than controls.

In 2013, the ATSDR (US Agency for Toxic Substances and Disease Registry) [1] established a minimum risk level for the ingestion of U, known by the acronym MRL (minimum risk level), which is 0.002 μg of U per kilo of weight per day. The MRL is an estimate of the daily exposure of a human being to a dangerous substance that probably does not represent an appreciable risk of adverse effects (excluding cancer) beyond the time of exposure. MRL values for both oral and inhalation routes vary with different exposure times: acute (1–14 days), intermediate (15–365 days), and chronic (365 days or longer).

Zamora *et al*. [19] studied the effects of chronic ingestion of U in humans after drinking contaminated water. They suggested that intake of U doses such as those found in some underground water wells over prolonged periods of time altered the renal function. These observed effects may represent a manifestation of subclinical toxicity that does not necessarily lead to renal dysfunction or obvious injury. Instead, it may be the first stage in a spectrum in which chronic intake of elevated U levels can lead to irreversible renal injury [20].

In addition to being ingested via drinking water, U can be taken in orally through contaminated food, mainly beef and fish.

The concentrations of U in fish muscle (per gram of dry weight) extracted from a Canadian lake contaminated by tributaries of a U processing plant were 7–11 times higher than in those from uncontaminated lakes [21]. Lapham *et al*. [22] analyzed U concentrations in cattle muscle and found that although U levels in the muscle of the exposed cattle were almost imperceptible with respect to the controls, U concentration in the liver and renal tissues was 4 times higher in the exposed cattle than in the control. Moreover, U levels in the bone (femur samples) were found to be 13 times higher than in the controls.

Other than beef and fish, some underground vegetables such as potatoes, sweet potatoes, and turnips contribute approximately 38% of the U intake per diet according to the general food consumption rate [23].

Although there are no studies in humans regarding the lethal effects of U and its compounds when ingested orally, several animal studies have shown that a very high intake dose of U can be lethal for acute (1–14 days), subacute (14–365 days), and chronic (more than 365 days) exposures [24].

Maynard and Hodge [1] obtained an LD50 (lethal dose 50 population %) value for oral (UN) of 1579 mg of U/kg/day in rats of both sexes (without specifying

strain) in a 30-day study. Maynard *et al*. [25] found 16% mortality in rats that were intoxicated with 664 mg/kg/day of U for 30 days orally. In our laboratory, Martinez *et al*. [26] studied the effects of a lethal dose of UN administered by gavage in male mice: we found that 350 mg/kg was the LD99 (lethal dose 99 population %) on the third day of the experiment.

Studies in rats suggest that the primary pathway for gastrointestinal absorption of soluble U is through the small intestinal epithelium [27, 28] via the transcellular pathway [29]. In the event of ingestion, the digestive tract is the first biological system exposed to U intake via the intestinal lumen. However, little research has addressed the biological consequences of contamination with U on intestinal properties such as the barrier function and/or the immune status of this tissue. Dublineau *et al*. [28, 29] studied both acute contamination with Depleted Uranium (DU) at high doses and chronic contamination at low doses on inflammatory reactions in the intestine when orally delivered. They found that acute and chronic ingestion of DU modulated expression and/or production of cytokines in the intestine and had similar effects to those observed with lead on the nitric oxide pathway.

#### **2.2 Inhalation route**

Inhalation is a major route of human exposure to environmental particles. When inhaled, U particles, based on their size, may be deposited on the lung ciliated epithelial lining or may reach the lower respiratory tract. Small particles of U containing dust could be inhaled by U miners and people living close to the mines, penetrating deeply into their lungs. The particles can be phagocytosed by alveolar macrophages (AM) and/or cross the alveolar capillary barrier, thereby reaching the bloodstream.

Uranium toxicity depends, among other things, on the solubility, dose, and route of exposure. In general, the more insoluble U compounds (uranium trioxide, uranium dioxide, uranium peroxide, and triuranium octaoxide) have greater potential for longterm effects in the lung, probably due to the long-term retention of the compound [1]. On the contrary, soluble U compounds (uranyl fluoride, 1 uranium tetrachloride, and uranyl nitrate hexahydrate), due to their easier absorption in the lungs and passage into the bloodstream, exert their action mainly on the extrapulmonary organs [1]. Thus, lungs and extrapulmonary organs are susceptible to negative impact by U particles.

Even though U can enter the body through different routes, macrophages are always the first cells to respond to these or any other xenobiotic agents. Primary cultured AM is a suitable *in vitro* model for studying the effects of U at cell level and its cytotoxic mechanism. Tasat and de Rey [30] demonstrated the adverse effects of insoluble uranium dioxide using AM obtained from rat bronchoalveolar lavage. The study revealed the ability of macrophages to phagocyte U particles in a short time despite the high toxicity that metal exerts on cell membranes. The ultrastructural analysis detected the U particles confined within intracytoplasmic vacuoles or free in the macrophage cytoplasm, which in turn could lead to cell death. More recently, Orona *et al*. [31] demonstrated that exposure to the soluble U compound UN, also induced cell death in cultured rat AM. The cytotoxic mechanism studied in this *in vitro* model showed that at low doses, UN stimulated phagocytosis and generation of superoxide anion (O2 <sup>−</sup>), while at high doses, it induced the secretion of TNFα. Therefore, Orona *et al*. suggested that cell death at low doses was principally mediated by reactive oxygen species (ROS), while the signaling pathway when exposed to higher UN doses was principally mediated by the release of pro-inflammatory mediators inhibiting the generation of ROS.

These authors hypothesized that an oxidant-antioxidant imbalance provoked by activated macrophages after U inhalation may lead to an alteration in macrophage

**119**

**2.3 Dermal contact**

**Figure 1.**

*2.3.1 Percutaneous absorption*

*Bisphosphonates as Chelating Agents in Uranium Poisoning*

with DNA lesions could be linked to the U compounds dose.

interest groups at both national and international levels.

metabolism. This cell response may in turn modify the pulmonary tissue microenvironment, thereby participating in the development of lung pathologies associated with U exposure. Uranium exposure involves both an occupational risk for miners and workers who handle it constantly, and an environmental hazard to the health of the population at large. Katz *et al*. [32] updated the chemistry, pharmacokinetics, and toxicological effects of U on several systems in the mammalian body which were previously reviewed by Craft *et al*. [33] and Briner [34]. However, the adverse impact on human health is still controversial. In this context, we studied the effect of UN on macrophages differentiated from human THP-1 monocytes. As is clearly shown in **Figure 1**, increasing doses of soluble UN provoked a significant decrease in macrophage-like cell viability, similar to what was observed with murine macrophages. Extrapolated to the *in vivo* situation, these findings might help to explain, in part, how acute or chronic inflammatory states observed in U-exposed individuals

Despite all the research conducted by the scientific community to clarify and understand the effect of both insoluble and soluble U compounds, the data reported appear to have somehow been compromised by the political agendas of special

Chemically induced renal failure caused 100% mortality in male Wistar rats after five daily exposures to 237 or 1928 mg U/kg/day as UN hexahydrate or ammonium uranyl tricarbonate, respectively, applied in a water-Vaseline® emulsion. A 60% mortality rate was also reported for other male Wistar rats that received daily applications of 1965 mg U/kg as uranyl acetate dihydrate for 1–11 days. No death was reported for other Wistar rats similarly treated with 2103 mg U/kg/day as

*Cell viability of macrophages differentiated from human THP-1 monocytes exposed to UN. Higher doses of UN caused a reduction in cell viability. Values are represented as mean ± SD. Results are compared* 

Decreased survival was observed in female Wistar rats following dermal application of 280 mg U as UN hexahydrate diluted in an oil–water emulsion; survival was inversely related to the duration of exposure and the application area [35]. A

ammonium diuranate or to an unspecified dose of UD [13].

*employing one-way ANOVA followed by Dunnett's test P < 0.001.*

*DOI: http://dx.doi.org/10.5772/intechopen.92220*

#### *Bisphosphonates as Chelating Agents in Uranium Poisoning DOI: http://dx.doi.org/10.5772/intechopen.92220*

metabolism. This cell response may in turn modify the pulmonary tissue microenvironment, thereby participating in the development of lung pathologies associated with U exposure. Uranium exposure involves both an occupational risk for miners and workers who handle it constantly, and an environmental hazard to the health of the population at large. Katz *et al*. [32] updated the chemistry, pharmacokinetics, and toxicological effects of U on several systems in the mammalian body which were previously reviewed by Craft *et al*. [33] and Briner [34]. However, the adverse impact on human health is still controversial. In this context, we studied the effect of UN on macrophages differentiated from human THP-1 monocytes. As is clearly shown in **Figure 1**, increasing doses of soluble UN provoked a significant decrease in macrophage-like cell viability, similar to what was observed with murine macrophages. Extrapolated to the *in vivo* situation, these findings might help to explain, in part, how acute or chronic inflammatory states observed in U-exposed individuals with DNA lesions could be linked to the U compounds dose.

Despite all the research conducted by the scientific community to clarify and understand the effect of both insoluble and soluble U compounds, the data reported appear to have somehow been compromised by the political agendas of special interest groups at both national and international levels.

#### **Figure 1.**

*Cell viability of macrophages differentiated from human THP-1 monocytes exposed to UN. Higher doses of UN caused a reduction in cell viability. Values are represented as mean ± SD. Results are compared employing one-way ANOVA followed by Dunnett's test P < 0.001.*

#### **2.3 Dermal contact**

#### *2.3.1 Percutaneous absorption*

Chemically induced renal failure caused 100% mortality in male Wistar rats after five daily exposures to 237 or 1928 mg U/kg/day as UN hexahydrate or ammonium uranyl tricarbonate, respectively, applied in a water-Vaseline® emulsion. A 60% mortality rate was also reported for other male Wistar rats that received daily applications of 1965 mg U/kg as uranyl acetate dihydrate for 1–11 days. No death was reported for other Wistar rats similarly treated with 2103 mg U/kg/day as ammonium diuranate or to an unspecified dose of UD [13].

Decreased survival was observed in female Wistar rats following dermal application of 280 mg U as UN hexahydrate diluted in an oil–water emulsion; survival was inversely related to the duration of exposure and the application area [35]. A

24-h application to areas of 0.5, 1, 2, 4, 6, 8, or 16 cm<sup>2</sup> resulted in survival rates of 80, 83, 67, 29, 33, 0, and 0%, respectively; application to 8 cm<sup>2</sup> for 1 min, 7 min, 15 min, 30 min, 1 h, 8 h, or 24 h resulted in survival rates of 100, 100, 100, 67, 45, 43, 10, and 0%, respectively.

#### *2.3.2 Subcutaneous absorption*

Subcutaneous or intradermal U contamination takes place in the presence of a wound. This poses a real risk to workers handling U dust on a daily basis and to soldiers who fought in the modern wars (Balkan, Gulf, etc.). Penetration of DU shrapnel bullets into the skin has become the focus of increasing attention. In fact, the only documented cases of exposure to U are those of the Gulf War veterans who retained DU shrapnel fragments [36].

Subcutaneous implantation of insoluble UO2 was investigated in our laboratory in an experimental animal model in rats by de Rey *et al*. [37]. This group showed that animals receiving doses higher than 0.01 g/kg died within the first 6 days due to acute renal failure. Histological analysis revealed the presence of deposits of uranium taken up by macrophages at 24 and 48 h postexposure. Deposits were found between the endothelial cells and the renal parenchyma, suggesting that the U insoluble compound implanted subcutaneously is transported and deposited.

#### **3. Uranium toxicity and its main target organs**

Regardless of the route of entry, U has two main target organs: the kidney and the bone. The magnitude of the adverse U impact in these two organs is dose- and time-dependent.

#### **3.1 Renal toxicity**

In 1991, the World Health Organization (WHO) identified U and other heavy metals such as lead, mercury, and cadmium as nephrotoxic elements. Early in 1949, Voegtlin and Hodge [38], in the framework of the Manhattan Project, studied the toxic effects of U in animal experimental models, finding characteristic histological features of kidney injury, regardless of the route of entry to the organism. Subsequently, many animal studies have shown that inhalation, oral exposure, or dermal exposure to uranium results in kidney damage [35, 39–41]. This damage was histologically manifested principally as glomerular and tubular wall degeneration. After being filtered by the renal glomerulus, the uranium-bicarbonate complex enters the glomerular urine. The bicarbonate is reabsorbed into the venous blood and loses the uranyl ion at the time of its passage through the proximal contoured tubule. The uranyl ion reacts with the membrane proteins of the cylindrical cells causing cell damage, and, when doses are high, cell death can occur, releasing the cell content into the urine [42]. Ultrastructural analysis showed damage to the endothelial cells in the glomerulus, such as loss of cell processes and reduction in the density of the endothelial fenestrae [43–46]. Although the most obvious effect of U exposure is damage to the proximal convoluted tubules, necrotic cells from the tubular epithelium have also been reported [19]. The histological alterations observed as a result of exposure to UN include partial degeneration, necrosis, and cast formation in proximal convoluted tubule although with damage to brush border, but glomeruli remain intact [47]. In our laboratory, we have observed that kidneys of exposed animals revealed the usual U-induced tubule necrosis lesions with abundant hyaline cylinders and extensive areas of necrosis after 48 h of 350 mg UN/kg b.w. exposure.

**121**

*Bisphosphonates as Chelating Agents in Uranium Poisoning*

the Bowman's capsule is evident [41] (**Figure 2**).

At glomerular level, although glomerulus structure appears to be intact, widening of

The analysis of autoradiographic, histological, and renal functioning studies showed that the site where the U produces greatest injury is the distal third of the proximal contoured tubule. If the tubular cells are not too damaged, they can repair the alterations and regenerate. Recovery is rapid despite the fact that the regenerated cells are atypical in some details, and within a few weeks or a month, both the biochemical parameters and renal histology are normalized. In 1982, Haley [44] studied different U compounds with special interest in their effects on the renal parenchyma. Of all the compounds studied, UN proved to be the most nephrotoxic compound, which explains why it is frequently used to produce experimental renal

The incorporation of U compounds into bone tissue has been demonstrated by biochemical analysis, autoradiographic methods, neutron activation analysis, and X-ray microanalysis. Many U isotopes are considered more as a chemical risk than as a radiological risk. The radioactivity of UN can be considered negligible, since the radioactivity of 238 U, as we have seen, is very low [48–50]. This would explain that bone formation alterations could be due preferably to the chemical toxicity of U [51]. As mentioned above, Hursh *et al*. [11] reported that 25% of the systemically administered U is deposited in the skeleton and tends to bind to the newly formed bone. Since the bone is the only tissue in which U deposits can be found a long time after exposure, it is considered to be the critical organ in chronic exposures, displacing the kidney as a target. Autoradiographic studies demonstrated initial U deposits on the surfaces of the endosteum, the periosteum, and the haversian bone, particularly in areas where calcification occurs. Back in 1948, Neuman *et al*. showed that there was an association between U deposits and bone formation [52], but at that time, it was not known whether this process was affected. Three decades later, for the first time, it was found that U also affects bone metabolism in acute poisoning. Guglielmotti *et al*. [53, 54] were the first to demonstrate, by means of histological and histomorphometric methods, that the inhibition of bone formation was a result of acute intoxication with UN. The study was carried out with Wistar rats

*Histopathology of kidney tissue from control and UN exposure groups. Cortical region of kidney: (A) control animal, intact tubular epithelium with no damage and (B) animal exposed to 350 mg UN/kg b.w., 48 h, tubular damage, loss of microvilli, extensive necrosis and cast formation in tubules, and necrosis of proximal tubular epithelium. Marked vacuolization of the tubules, abundant hyaline cylinders, and extensive areas of necrosis. Widening of the uriniferous tubule and of Bowman's capsule is also evident (HE 400X).*

*DOI: http://dx.doi.org/10.5772/intechopen.92220*

failure.

**Figure 2.**

**3.2 Effects on bone tissue**

#### *Bisphosphonates as Chelating Agents in Uranium Poisoning DOI: http://dx.doi.org/10.5772/intechopen.92220*

At glomerular level, although glomerulus structure appears to be intact, widening of the Bowman's capsule is evident [41] (**Figure 2**).

The analysis of autoradiographic, histological, and renal functioning studies showed that the site where the U produces greatest injury is the distal third of the proximal contoured tubule. If the tubular cells are not too damaged, they can repair the alterations and regenerate. Recovery is rapid despite the fact that the regenerated cells are atypical in some details, and within a few weeks or a month, both the biochemical parameters and renal histology are normalized. In 1982, Haley [44] studied different U compounds with special interest in their effects on the renal parenchyma. Of all the compounds studied, UN proved to be the most nephrotoxic compound, which explains why it is frequently used to produce experimental renal failure.

#### **Figure 2.**

*Histopathology of kidney tissue from control and UN exposure groups. Cortical region of kidney: (A) control animal, intact tubular epithelium with no damage and (B) animal exposed to 350 mg UN/kg b.w., 48 h, tubular damage, loss of microvilli, extensive necrosis and cast formation in tubules, and necrosis of proximal tubular epithelium. Marked vacuolization of the tubules, abundant hyaline cylinders, and extensive areas of necrosis. Widening of the uriniferous tubule and of Bowman's capsule is also evident (HE 400X).*

#### **3.2 Effects on bone tissue**

The incorporation of U compounds into bone tissue has been demonstrated by biochemical analysis, autoradiographic methods, neutron activation analysis, and X-ray microanalysis. Many U isotopes are considered more as a chemical risk than as a radiological risk. The radioactivity of UN can be considered negligible, since the radioactivity of 238 U, as we have seen, is very low [48–50]. This would explain that bone formation alterations could be due preferably to the chemical toxicity of U [51]. As mentioned above, Hursh *et al*. [11] reported that 25% of the systemically administered U is deposited in the skeleton and tends to bind to the newly formed bone. Since the bone is the only tissue in which U deposits can be found a long time after exposure, it is considered to be the critical organ in chronic exposures, displacing the kidney as a target. Autoradiographic studies demonstrated initial U deposits on the surfaces of the endosteum, the periosteum, and the haversian bone, particularly in areas where calcification occurs. Back in 1948, Neuman *et al*. showed that there was an association between U deposits and bone formation [52], but at that time, it was not known whether this process was affected. Three decades later, for the first time, it was found that U also affects bone metabolism in acute poisoning. Guglielmotti *et al*. [53, 54] were the first to demonstrate, by means of histological and histomorphometric methods, that the inhibition of bone formation was a result of acute intoxication with UN. The study was carried out with Wistar rats

(weighing 90 g/b.w.) intoxicated with a dose of 2 mg/kg of UN applied intraperitoneally, and observations were made at the level of the endochondral ossification of the tibia. After 14 days, inhibition of endochondral ossification of the tibia was observed in the intoxicated animals but not in the control animals. In a histomorphometric analysis of the bone of intoxicated animals, they found a decrease in bone surfaces covered by active osteoblasts and the consequent increase in inactive osteoblasts. Such results were attributed to U, which has been suggested to cause alterations in the osteoblast differentiation process or in their cell precursors. At the same time, the remaining osteoblasts may form the sealing trabeculae that were seen in the metaphyseal bone.

In 1987, Guglielmotti *et al*. [55] used the same animal model to study the effect of a low dose of UN (0.8 mg/kg) on tooth extraction socket healing over time (14, 30, and 60 days post-surgery). Results revealed a delay in socket healing with respect to controls. At low doses, U exerted its toxic effect on the recruitment and/ or differentiation of osteoblasts, despite the cell damage, and dramatically inhibited bone formation observed after acute poisoning.

Ubios *et al*. [56] confirmed the results described above through ultrastructural studies in which they also detected the presence of small electron-dense deposits in the osteoblast cell membrane, inferring that they were U particles. The inhibitory UN effect on bone formation was evidenced as a reduction in bone growth of tibiae and mandibles [57, 58] and as a delay in tooth eruption [59]. In 2007, Tasat *et al*. [60] showed that UN modified osteoblast cell metabolism by increasing reactive oxygen species generation and reducing alkaline phosphatase activity, suggesting that ROS could play a more complex role in cell physiology than simply by causing oxidative damage.

The effects of U on bone formation are evident not only in situations of active ossification, but we have also observed them in bone modeling and remodeling, where, in addition, the reduction in bone formation activity was associated with an increase in bone resorption [61]. Nevertheless, while many studies have focused on the effect of U on bone formation and osteoblasts, the impact of U on bone resorption has been poorly explored. In this context, Ubios *et al*. [61] conducted a pioneering study demonstrating an increase in resorption of the alveolar bone of the jaws after intraperitoneal injection of UN in Wistar rats. Subsequently, in our laboratory, we have also observed a histomorphometrical increase in resorption surfaces in metaphyseal bone after oral administration of a lethal oral dose of UN [62]. Recent studies have revealed dose- and time-dependent U cytotoxicity on pre-osteoclast cell lines, impairing osteoclast formation and function [63].

#### **4. Chelating agents in uranium poisoning**

Uranium toxicity has been a concern for over 100 years. The toxicology of many forms of uranium, ranging from dust of several oxides to soluble uranyl ions, was thoroughly studied during the Manhattan Project in the United States in the 1940s [64]. Data available in the literature show that most studies have focused on finding a compound that accelerates U decorporation after it has reached the target organs: kidney (acute intoxication) and bone (chronic exposure).

From a pharmacological standpoint, different methods have been tested to counteract the toxic effect of U. Several chelating agents such as EDTA, Tiron, DTPA, or aminosalicylic acid have been experimentally assayed. However, even when these agents are able to reduce mortality, none of them achieve 100% survival. Bicarbonate can be administered to reduce U body burdens due to acute exposures. Bicarbonate ions form a complex with U and alkalize the blood, both

**123**

*Bisphosphonates as Chelating Agents in Uranium Poisoning*

of which enhance the excretion from the kidneys by glomerular filtration [65], and such an application was described in a case of prophylactic treatment [66]. Experimental evidence in animals indicates that chelation therapy may reduce the body burden of U. Several compounds were found to enhance the urinary and fecal excretion of U if administered soon after U exposure. When administered immediately after exposure to U, Tiron® (sodium 4,5-dihydroxybenzene-1,3-disulfonate) resulted in the greatest reduction in renal and bone levels of U and acute lethal effects in animals [67, 68]. None of the chelating agents affected bone levels of U when administered ≥24 h after exposure to U [68]. Bicarbonate treatment is also limited to very near-term exposures. Another study that tested Tiron alone and in conjunction with either DTPA or ethylenediamine-N,N=-bis(2-hydroxyphenylacetic acid) (EDHPA) found that it reduced the U body burden by no more than about 35%, indicating that the administration of Tiron® is of limited practical value for the treatment of U exposures that do not greatly exceed the permitted intake level [69]. Our group began working with a bisphosphonate, ethane-1-hydroxy-1,1-bisphosphonate (EHBP) in 1986 based on the beneficial effect of bisphosphonates on bone when they are used in correct doses. Ubios *et al*. [70] showed the attenuation of the inhibitory effect of radiation on bone formation when the animals were treated with ethane-1-hydroxy-1,1-bisphosphonate (EHBP). In acute intoxication, U not only inhibits bone formation, but its excretion in urine also causes renal damage. The former effect is ameliorated by tetracycline (TC), probably due to its chelation property, which might also prevent U deposition in bone. Chemical determination of U incorporated in the bone and a histological study of the kidneys were performed by Guglielmotti *et al*. [71] on animals injected with U and then treated with TC. The results showed that TC was unable to prevent the binding of U to the bone, while it exacerbated U-induced renal damage. Ubios *et al*. [72] reported the beneficial effect of ethane 1-hydroxy-1,1-diphosphonate (EHDP) in restoring the inhibition of bone formation in cases of acute U intoxication in a post-extraction wound healing rat model. Ubios *et al*. [57] showed the use of a single subcutaneous injection of ethane-1-hydroxy-1,1-bisphosphonate to prevent mortality due to

Of the chelation therapies that have been studied in animals, it appears that citric acid and citrate salts might be the most practical to employ in conflict areas where DU weapons have been used. Citric acid/citrate consumption should be recommended to anyone in areas where uranium aerosols might be found. Fructose and/or sucrose that may be present in some beverages that contain high levels of

**4.1 Bisphosphonates as chelating agents to avoid lethal poisoning by uranium**

Bisphosphonates are used clinically to prevent osteoclastic bone resorption. Their use tends to achieve positive bone formation/resorption balance. These compounds are used to treat osteoporosis, a very common lesion in postmenopausal women in which the bone formation/resorption equation is altered (predominantly resorption), and the final matrix tends to decrease in volume, sometimes reaching mechanically dangerous situations due to fractures, among other problems.

The biological effects of bisphosphonates (BPs) as inhibitors of calcification and bone resorption were first described in the late 1960s. In the 50 years that have elapsed since then, BPs have become the leading drugs for the treatment of skeletal disorders characterized by increased bone resorption, including Paget's disease of the bone, bone metastases, multiple myeloma, osteoporosis, and childhood inherited bone disorders as osteogenesis imperfecta. The discovery and

*DOI: http://dx.doi.org/10.5772/intechopen.92220*

uranium poisoning in a rat model.

citrates should be avoided [64].

#### *Bisphosphonates as Chelating Agents in Uranium Poisoning DOI: http://dx.doi.org/10.5772/intechopen.92220*

of which enhance the excretion from the kidneys by glomerular filtration [65], and such an application was described in a case of prophylactic treatment [66]. Experimental evidence in animals indicates that chelation therapy may reduce the body burden of U. Several compounds were found to enhance the urinary and fecal excretion of U if administered soon after U exposure. When administered immediately after exposure to U, Tiron® (sodium 4,5-dihydroxybenzene-1,3-disulfonate) resulted in the greatest reduction in renal and bone levels of U and acute lethal effects in animals [67, 68]. None of the chelating agents affected bone levels of U when administered ≥24 h after exposure to U [68]. Bicarbonate treatment is also limited to very near-term exposures. Another study that tested Tiron alone and in conjunction with either DTPA or ethylenediamine-N,N=-bis(2-hydroxyphenylacetic acid) (EDHPA) found that it reduced the U body burden by no more than about 35%, indicating that the administration of Tiron® is of limited practical value for the treatment of U exposures that do not greatly exceed the permitted intake level [69]. Our group began working with a bisphosphonate, ethane-1-hydroxy-1,1-bisphosphonate (EHBP) in 1986 based on the beneficial effect of bisphosphonates on bone when they are used in correct doses. Ubios *et al*. [70] showed the attenuation of the inhibitory effect of radiation on bone formation when the animals were treated with ethane-1-hydroxy-1,1-bisphosphonate (EHBP). In acute intoxication, U not only inhibits bone formation, but its excretion in urine also causes renal damage. The former effect is ameliorated by tetracycline (TC), probably due to its chelation property, which might also prevent U deposition in bone. Chemical determination of U incorporated in the bone and a histological study of the kidneys were performed by Guglielmotti *et al*. [71] on animals injected with U and then treated with TC. The results showed that TC was unable to prevent the binding of U to the bone, while it exacerbated U-induced renal damage. Ubios *et al*. [72] reported the beneficial effect of ethane 1-hydroxy-1,1-diphosphonate (EHDP) in restoring the inhibition of bone formation in cases of acute U intoxication in a post-extraction wound healing rat model. Ubios *et al*. [57] showed the use of a single subcutaneous injection of ethane-1-hydroxy-1,1-bisphosphonate to prevent mortality due to uranium poisoning in a rat model.

Of the chelation therapies that have been studied in animals, it appears that citric acid and citrate salts might be the most practical to employ in conflict areas where DU weapons have been used. Citric acid/citrate consumption should be recommended to anyone in areas where uranium aerosols might be found. Fructose and/or sucrose that may be present in some beverages that contain high levels of citrates should be avoided [64].

#### **4.1 Bisphosphonates as chelating agents to avoid lethal poisoning by uranium**

Bisphosphonates are used clinically to prevent osteoclastic bone resorption. Their use tends to achieve positive bone formation/resorption balance. These compounds are used to treat osteoporosis, a very common lesion in postmenopausal women in which the bone formation/resorption equation is altered (predominantly resorption), and the final matrix tends to decrease in volume, sometimes reaching mechanically dangerous situations due to fractures, among other problems.

The biological effects of bisphosphonates (BPs) as inhibitors of calcification and bone resorption were first described in the late 1960s. In the 50 years that have elapsed since then, BPs have become the leading drugs for the treatment of skeletal disorders characterized by increased bone resorption, including Paget's disease of the bone, bone metastases, multiple myeloma, osteoporosis, and childhood inherited bone disorders as osteogenesis imperfecta. The discovery and development of BPs as a major class of drugs for the treatment of bone diseases is a paradigm for the successful journey from "bench to bedside and back again." Several of the leading BPs achieved "blockbuster" status as branded drugs. However, these BPs have now come to the end of their patent life, making them highly affordable. The opportunity for new clinical applications for BPs also exists in other areas of medicine such as aging, cardiovascular disease, and radiation protection.

In our laboratory, based in data published by Ubios *et al*. [57], we designed animal experiments to focus on the potential of EHBP to prevent death after the administration of lethal oral doses of UN. In 2000, Martinez *et al*. [26] demonstrated, for the first time, that a single administration of EHBP is effective in reducing the lethal effect of U, and it is at least as useful as subcutaneous administration for prompt therapy of oral U exposure, achieving a survival rate of almost 50%. Tubule necrosis lesions were present in kidneys of mice intoxicated with UN, whereas lesions were less severe in mice treated with EHBP.

Based on the aforementioned results, Martinez *et al*. [41] evaluated the efficacy of EHBP in preventing renal dysfunction induced by a lethal dose of UN, employing serum levels of urea and creatinine as endpoints. Two experiments were performed with different time periods: 48 h and 14 days in male Balb/c mice with 25 g average body weight. Three of these groups received 350 mg/kg body weight of UN by gavage (forced oral administration). Two of the three exposed groups were treated with EHBP either by gavage in a dose of 500 mg/kg body weight or with a subcutaneous injection of 50 mg/kg body weight. The fourth group served as control. Urea and creatinine serum levels were markedly lower at 48 h in exposed animals treated with EHBP than in untreated exposed animals. On day 14 these values in exposed and treated animals did not differ significantly from control values. The renal function of animals treated with oral or subcutaneous EHBP that survived UN exposure was markedly improved compared to the controls of untreated exposed animals at 48 h. At 14 days, treatment with EHBP averted renal damage and the histologic study of kidneys showed images of tissue recovery (**Figure 3**). These results suggest that the use of EHBP may be of great value in reducing renal damage.

Bozal *et al*. [62] showed that all growth cartilage and metaphyseal bone histomorphometric parameters were significantly lower in animals exposed to UN at 48 h than in controls. EHBP administration was found to prevent this condition at 48 h reaching similar values to those of controls. Although histomorphometric values did not reach control values at 14 days, they were higher than those of animals exposed to UN at 48 h not treated with EHBP. It is noteworthy that these values also decreased in animals

#### **Figure 3.**

*(HE 100X) Histological sections of cortical zone of kidneys of a control animal (A), of an animal 48 h post-intoxication with uranyl nitrate (UN) (B), and of an animal intoxicated with UN and treated with oral EHBP, 14 days post-intoxication (C). (A) Note the integrity of tubule and glomerular structure. (B) Note the marked vacuolization of the tubules, abundant hyaline cylinders, and extensive areas of necrosis, all of them usual uranium-induced lesions. (C) Note that instead the presence of scattered hyaline cylinders, the tissue shows marked recovery of renal architecture.*

**125**

**5. Discussion**

**Figure 5.**

*Bisphosphonates as Chelating Agents in Uranium Poisoning*

only receiving EHBP at 14 days. Our results show that EHBP effectively ameliorates the adverse effects of a lethal dose of UN on endochondral ossification (**Figure 4**). In our laboratory, we have also evaluated the effect of treatment with EHBP on the reduction in interradicular bone volume and the alteration of histomorphometric parameters of bone remodeling in animals intoxicated with a lethal oral dose of UN (unpublished data). These studies showed that 48 h after UN intoxication, EHBP treatment enables an interradicular bone volume to be maintained which is similar to the controls, and this condition is sustained 14 days post-treatment (**Figure 5**). Moreover, at 48 h, EHBP prevented the reduction in bone formation and increase in bone resorption caused by UN intoxication in the interradicular bone of

*(HE 100X) Histological sections of the metaphyseal bone of a control animal (A), of an animal 48 h postintoxication with uranyl nitrate (UN) (B), and of an animal intoxicated with UN and treated with oral EHBP, 14 days post-intoxication (C). Note the marked reduction in cartilage width and the absence of proliferation cells in the growth cartilage as well as the absence of subchondral bone in UN-exposed animal (B) compared to the control (A). In animal intoxicated with UN and treated with EHBP (C), note that instead of the reduction in cartilage width compared to the control, proliferation cells in the growth cartilage and* 

Our research shows that in adult mice that had been exposed to a lethal dose of orally administered UN, a single dose of EHBP—either by mouth or subcutaneous—reduced mortality by about 50%. Surviving exposed animals

*to UN and how, in the exposed animals treated with EHBP, bone volume is similar to the control.*

*(HE 100X) Histological sections of the interradicular alveolar bone of a control animal (A), of an animal 48 h post-intoxication with UN (B), and of an animal intoxicated with UN and treated with oral EHBP, 14 days post-intoxication (C). The images show the reduction in interradicular bone volume at 48 h in animals exposed* 

*DOI: http://dx.doi.org/10.5772/intechopen.92220*

intoxicated animals.

*subchondral bone are evident.*

**Figure 4.**

#### *Bisphosphonates as Chelating Agents in Uranium Poisoning DOI: http://dx.doi.org/10.5772/intechopen.92220*

only receiving EHBP at 14 days. Our results show that EHBP effectively ameliorates the adverse effects of a lethal dose of UN on endochondral ossification (**Figure 4**).

In our laboratory, we have also evaluated the effect of treatment with EHBP on the reduction in interradicular bone volume and the alteration of histomorphometric parameters of bone remodeling in animals intoxicated with a lethal oral dose of UN (unpublished data). These studies showed that 48 h after UN intoxication, EHBP treatment enables an interradicular bone volume to be maintained which is similar to the controls, and this condition is sustained 14 days post-treatment (**Figure 5**). Moreover, at 48 h, EHBP prevented the reduction in bone formation and increase in bone resorption caused by UN intoxication in the interradicular bone of intoxicated animals.

#### **Figure 4.**

*(HE 100X) Histological sections of the metaphyseal bone of a control animal (A), of an animal 48 h postintoxication with uranyl nitrate (UN) (B), and of an animal intoxicated with UN and treated with oral EHBP, 14 days post-intoxication (C). Note the marked reduction in cartilage width and the absence of proliferation cells in the growth cartilage as well as the absence of subchondral bone in UN-exposed animal (B) compared to the control (A). In animal intoxicated with UN and treated with EHBP (C), note that instead of the reduction in cartilage width compared to the control, proliferation cells in the growth cartilage and subchondral bone are evident.*

#### **Figure 5.**

*(HE 100X) Histological sections of the interradicular alveolar bone of a control animal (A), of an animal 48 h post-intoxication with UN (B), and of an animal intoxicated with UN and treated with oral EHBP, 14 days post-intoxication (C). The images show the reduction in interradicular bone volume at 48 h in animals exposed to UN and how, in the exposed animals treated with EHBP, bone volume is similar to the control.*

#### **5. Discussion**

Our research shows that in adult mice that had been exposed to a lethal dose of orally administered UN, a single dose of EHBP—either by mouth or subcutaneous—reduced mortality by about 50%. Surviving exposed animals had adequate renal function and showed a reduction in the deleterious effects of uranium on endochondral ossification and alveolar bone [41, 62]. We decided to administer UN by mouth so that the experimental models would replicate, as closely as possible, the situation of workers exposed to potential accidents. Given the similarity in survival rates observed with both the EHBP administration routes tested at our laboratory, we suggest that its effectiveness as a chelator to reduce the lethal effects of uranium is independent of whether it is administered orally or subcutaneously. In contrast to other studies, it is important to highlight that in the experimental design tested at our laboratory, all animals had free access to food and drink throughout, in order to recreate a situation that would similar to what might happen in case of accidental U intoxication to humans. This information reinforces the potential use of EHBP as an antidote to U, highlighting its easy accessibility for use in accidental intoxications when it is impossible to know the content of the gastrointestinal tract of the individual and which may ultimately interfere with the pharmacokinetics or pharmacological efficacy of EHBP. It is worth noting that at that time, there was no report in the literature of exposure to uranium and administration of an antidote via the same route—in our case, by mouth. EHBP was selected as uranium chelating agent based on the findings of Ubios *et al*. [72], who postulated that since bisphosphonates have proven affinity for calcium [73], they may act as U chelating agents. That study demonstrated the efficacy of only one injection of EHBP to prevent renal damage and counteract mortality due to uranium poisoning with a success rate of 100% [72].

Several studies have focused on the efficacy of different chelating agents for removing uranium from tissue deposits. However, chelation of a heavy metal is more beneficial than its removal from tissue deposits because it prevents it from reaching target organs. This property has been demonstrated experimentally in biochemical, histological, and histomorphometric studies on the kidney [41] and bones [62] of animals exposed to lethal doses of uranyl nitrate.

One favorable factor was the brief time—20 min in our studies—elapsed between the administration of U and the administration of EHBP. The time that elapses between administration of U and the antidote is critical. Catsch *et al*. [74] demonstrated that there is no apparent benefit from administrating an antidote if the time elapsed is longer than 6 h. Ubios *et al*. [75] tested the application of single doses of two different bisphosphonates acting as chelating agents—EHBP and APD (pamidronate)—observing that the animals treated with EHBP or APD up to 24 h after the exposure achieved 100% survival until the 60th day. Only when it was given 48 h after the exposure to uranium, EHBP appeared unable to prevent death. The intervals proposed by other authors range from 10 min to 24 h [67, 76, 77], with better results having been achieved by those who administered the chelating agent 10 min to 3 h post-intoxication (Tiron, in this case). It is worth noting that none of the experimental cases reported achieved a higher survival rate than we did. Some authors highlighted the importance of administrating repeated doses of the chelating agent in order to achieve a higher survival rate in animals intoxicated with U compounds [67, 76, 77] without having achieved better results than with a single dose.

#### **6. Conclusion**

The effects of a lethal dose of uranyl nitrate can be counteracted by the chelating action of bisodic etidronate administered by mouth or subcutaneously. The therapeutic effect of EHBP has been demonstrated using an animal model of

**127**

*Bisphosphonates as Chelating Agents in Uranium Poisoning*

uranium intoxication. Administration of EHBP provided a survival rate of 45–50%; returned serum renal biomarkers to values close to normal, which is consistent with reduction in hyalinization and necrotic areas; and reduced bone growth inhibition, reverting the damage typical of acute uranium intoxication. These results suggest that EHBP is a chelating agent capable of effectively neutralizing lethal uranium

In Memoriam of Dr. Romulo Luis Cabrini, who was our Laboratory Director for more than 40 years and our scientific guide in the field of uranium toxicology

\*, Carola Bettina Bozal<sup>2</sup>

1 Pharmacology Department, Faculty of Dentistry, National University of Rosario,

2 Universidad de Buenos Aires, Facultad de Odontología, Cátedra de Histología y

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

3 School of Science and Technology, National University of San Martin,

\*Address all correspondence to: adrianabmartinez@yahoo.com.ar

, Nadia Soledad Orona<sup>3</sup>

, Deborah

*DOI: http://dx.doi.org/10.5772/intechopen.92220*

intoxication.

research.

**Author details**

Argentina

Adriana Beatriz Martínez1

Buenos Aires, Argentina

Ruth Tasat2,3 and Angela Matilde Ubios2

Embriología, Buenos Aires, Argentina

provided the original work is properly cited.

**Acknowledgements**

uranium intoxication. Administration of EHBP provided a survival rate of 45–50%; returned serum renal biomarkers to values close to normal, which is consistent with reduction in hyalinization and necrotic areas; and reduced bone growth inhibition, reverting the damage typical of acute uranium intoxication. These results suggest that EHBP is a chelating agent capable of effectively neutralizing lethal uranium intoxication.

### **Acknowledgements**

In Memoriam of Dr. Romulo Luis Cabrini, who was our Laboratory Director for more than 40 years and our scientific guide in the field of uranium toxicology research.

### **Author details**

Adriana Beatriz Martínez1 \*, Carola Bettina Bozal<sup>2</sup> , Nadia Soledad Orona<sup>3</sup> , Deborah Ruth Tasat2,3 and Angela Matilde Ubios2

1 Pharmacology Department, Faculty of Dentistry, National University of Rosario, Argentina

2 Universidad de Buenos Aires, Facultad de Odontología, Cátedra de Histología y Embriología, Buenos Aires, Argentina

3 School of Science and Technology, National University of San Martin, Buenos Aires, Argentina

\*Address all correspondence to: adrianabmartinez@yahoo.com.ar

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

#### **References**

[1] Toxicological Phealth and rofile for Uranium. U.S. Department of Health and Human Services. Agency for Toxic Substances and Disease Registry. 2013. Available from: https://www.atsdr. cdc.gov/sites/toxzine/docs/uranium\_ toxzine.pdf [Accessed: 07 March 2020]

[2] Clarksson T. Factors involved in heavy metals poisoning. Federation Proceedings. 2002;**36**(5):1634-1639

[3] International Comission on Radiation Protection (ICRP). Age-Dependent Doses to Members of the Public from Intake of Radionuclides: Part 4, Inhalation Dose Coefficients. ICRP Publication 71. Oxford: Pergamon Press; 1996

[4] Hursh J, Spoor N. Data on man. In: Hodge H, Stannard J, Hursh J, editors. Uranium, Plutonium Transplutonic Elements. Handbook of Experimental Pharmacology. Vol. 36. Berlin/ Heidelberg: Springer Verlag; 1973. pp. 197-239

[5] Walinder G, Hammarstrom L, Billandelle U. Incorporation of uranium. I. Distribution of intravenously and intraperitoneally injected uranium. British Journal of Industrial Medicine. 1967;**24**:305-312. DOI: 10.1136/ oem.24.4.305

[6] La Touche Y, Willis D, Dawydiak O. Absorption and biokinetics of U in rats following an oral administration of uranyl nitrate solution. Health Physics. 1987;**53**:147-162. DOI: 10.1097/00004032-198708000-00005

[7] Durbin P, Wrenn M. Metabolism and effects of uranium in animals. In: Wrenn M, editor. Conference: Occupational Health Experience with Uranium, Arlington, VA. Vol. 93. Washington, DC: U.S. Energy Research and Development Administration (ERDA); 1975. pp. 67-129

[8] Sullivan M, Ruemmler P, Ryan J, Buschbom R. Influence of oxidizing or reducing agents on gastrointestinal absorption of U, Pu, Am, Cm and Pm by rats. Health Physics. 1986;**50**(2):223-232. DOI: 10.1097/00004032-198602000-00006

[9] Vidaud C, Dedieu A, Basset C, Plantevin S, Dany, Olivier Pible I, et al. Screening of human serum proteins for uranium binding. Chemical Research in Toxicology. 2005;**18**(6):946-953. DOI: 10.1021/tx050038v

[10] Wedeen R. Renal diseases of occupational origin. Occupational Medicine. 1992;**7**(3):449-463

[11] Hursh J, Neuman W, Toribara T, Wilson H, Waterhouse C. Oral ingestion of uranium by man. Health Physics. 1969;**17**:619-621

[12] Orcutt J. The toxicology of compounds of uranium following application to the skin. In: Voegtlin C, Hodge HC, editors. Pharmacology and Toxicology of Uranium Compounds, Vols. 3 and 4. New York, NY: McGraw Hill Book Co.; 1949. pp. 377-414

[13] de Rey B, Lanfranchi H, Cabrini R. Percutaneous absorption of uranium compounds. Environmental Research. 1983;**30**:480-491. DOI: 10.1016/0013-9351(83)90233-5

[14] Harris BW et al. Experimental clearance of urannium dust from the body. In: Darries CN, editor. Inhaled Particles and Vapours. London, UK: Pergamon; 1961

[15] Kurttio P, Harmoinen A, Saha H, Salonen L, Karpas Z, Komulainen H, et al. Kidney toxicity of ingested uranium from drinking water. American Journal of Kidney Diseases. 2006;**47**(6):972-982. DOI: 10.1053/j. ajkd.2006.03.002

**129**

24049861

*Bisphosphonates as Chelating Agents in Uranium Poisoning*

[25] Maynard E, Down W, Hodge H. Oral toxicity of uranium compounds. In: Voegtlin C, Hodge H, editors. Pharmacology and Toxicology of Uranium Compounds. New York, NY:

[26] Martinez A, Cabrini R, Ubios A. Orally administered ethane-1-hydroxy-1,1-bisphosphonate reduces the lethal effect of oral uranium poisoning. Health Physics. 2000;**78**:668-671. DOI: 10.1097/00004032-200006000-00009

[27] Dublineau I, Grison S, Baudelin C, Dudoignon N, Souidi M, Marquette C, et al. Absorption of uranium through the entire gastrointestinal tract of the rat. International Journal of Radiation Biology. 2005;**81**(6):473-482. DOI: 10.1080/09553000500196029

[28] Dublineau I, Grison S, Linard C, Baudelin C, Dudoignon N, Souidi M, et al. Short-term effects of depleted uranium on immune status in rat intestine. Journal of Toxicology and Environmental Health.

Part A. 2006;**69**(17):1613-1628. DOI:

Grison S, Baudelin C, Paquet F, Voisin P, et al. Modifications of inflammatory pathways in rat intestine following chronic ingestion of depleted uranium. Toxicological Sciences. 2007;**98**(2): 458-468. DOI: 10.1093/toxsci/kfm132

[30] Tasat DR, de Rey BM. Cytotoxic effect of uranium dioxide on rat alveolar macrophages. Environmental Research. 1987;**44**:71-81. DOI: 10.1016/

[31] Orona NS, Tasat DR. Uranyl nitrateexposed rat alveolar macrophages cell death: Influence of superoxide anion and TNF α mediators. Toxicology and Applied Pharmacology.

2012;**261**(3):309-316. DOI: 10.1016/j.

s0013-9351(87)80087-7

taap.2012.04.022

10.1080/15287390600629825

[29] Dublineau I, Grandcolas L,

McGraw-Hill; 1953

*DOI: http://dx.doi.org/10.5772/intechopen.92220*

[16] Kathren R, Burklin R. Acute chemical toxicity of uranium. Health Physics. 2008;**94**(2):170-179. DOI: 10.1097/01.HP.0000288043.94908.1f

The gastrointestinal absorption of protactinium, uranium, and neptunium in the hamster. Radiation Research.

[18] Anke M, Seebera O, Muller R, Schafer U, Zerull. Uranium transfer in the food chain from soil to plants, animals and man. Chemie der Erde-Geochemistry. 2009;**69**:75-90. DOI: 10.1016/j.chemer.2007.12.001

[19] Zamora M, Tracy B, Zielinski J, Meyerhof D, Moss M. Chronic ingestion

of uranium in drinking water: A study of kidney bioeffects in humans. Toxicological Sciences. 1998;**43**(1): 68-77. DOI: 10.1006/toxs.1998.2426

[20] WISE Uranium Project. 1999. Available from: www.wiseproject.org [Accessed: 20 December 2019]

[21] Swanson S. Food chain transfer of U-series radionuclides in northern Saskatchewan aquatic system. Health Physics. 1985;**49**:747-770. DOI: 10.1097/00004032-198511000-00008

[22] Lapham S, Millard J, Samet J. Health implications of radionuclide levels in cattle raised near uranium mining and milling facilities in Ambrosia Lake, New Mexico. Health Physics. 1989;**36**(3):327-330. DOI: 10.1097/00004032-198903000-00008

[23] EPA-US Environmental Protective Agency Code of Federal Regulation CFR

[24] US Department of Health & Human Services. Public Health Service. Agency for Toxic Substances and Disease Registry. Research Triangle Institute "Uranium: Draft for Public Comment"; 1997. Bookshelf ID: NBK158802PMID:

421, Subpart AD; 1985

[17] Harrison J, Stather J.

1981;**88**(1):47-55

*Bisphosphonates as Chelating Agents in Uranium Poisoning DOI: http://dx.doi.org/10.5772/intechopen.92220*

[16] Kathren R, Burklin R. Acute chemical toxicity of uranium. Health Physics. 2008;**94**(2):170-179. DOI: 10.1097/01.HP.0000288043.94908.1f

[17] Harrison J, Stather J. The gastrointestinal absorption of protactinium, uranium, and neptunium in the hamster. Radiation Research. 1981;**88**(1):47-55

[18] Anke M, Seebera O, Muller R, Schafer U, Zerull. Uranium transfer in the food chain from soil to plants, animals and man. Chemie der Erde-Geochemistry. 2009;**69**:75-90. DOI: 10.1016/j.chemer.2007.12.001

[19] Zamora M, Tracy B, Zielinski J, Meyerhof D, Moss M. Chronic ingestion of uranium in drinking water: A study of kidney bioeffects in humans. Toxicological Sciences. 1998;**43**(1): 68-77. DOI: 10.1006/toxs.1998.2426

[20] WISE Uranium Project. 1999. Available from: www.wiseproject.org [Accessed: 20 December 2019]

[21] Swanson S. Food chain transfer of U-series radionuclides in northern Saskatchewan aquatic system. Health Physics. 1985;**49**:747-770. DOI: 10.1097/00004032-198511000-00008

[22] Lapham S, Millard J, Samet J. Health implications of radionuclide levels in cattle raised near uranium mining and milling facilities in Ambrosia Lake, New Mexico. Health Physics. 1989;**36**(3):327-330. DOI: 10.1097/00004032-198903000-00008

[23] EPA-US Environmental Protective Agency Code of Federal Regulation CFR 421, Subpart AD; 1985

[24] US Department of Health & Human Services. Public Health Service. Agency for Toxic Substances and Disease Registry. Research Triangle Institute "Uranium: Draft for Public Comment"; 1997. Bookshelf ID: NBK158802PMID: 24049861

[25] Maynard E, Down W, Hodge H. Oral toxicity of uranium compounds. In: Voegtlin C, Hodge H, editors. Pharmacology and Toxicology of Uranium Compounds. New York, NY: McGraw-Hill; 1953

[26] Martinez A, Cabrini R, Ubios A. Orally administered ethane-1-hydroxy-1,1-bisphosphonate reduces the lethal effect of oral uranium poisoning. Health Physics. 2000;**78**:668-671. DOI: 10.1097/00004032-200006000-00009

[27] Dublineau I, Grison S, Baudelin C, Dudoignon N, Souidi M, Marquette C, et al. Absorption of uranium through the entire gastrointestinal tract of the rat. International Journal of Radiation Biology. 2005;**81**(6):473-482. DOI: 10.1080/09553000500196029

[28] Dublineau I, Grison S, Linard C, Baudelin C, Dudoignon N, Souidi M, et al. Short-term effects of depleted uranium on immune status in rat intestine. Journal of Toxicology and Environmental Health. Part A. 2006;**69**(17):1613-1628. DOI: 10.1080/15287390600629825

[29] Dublineau I, Grandcolas L, Grison S, Baudelin C, Paquet F, Voisin P, et al. Modifications of inflammatory pathways in rat intestine following chronic ingestion of depleted uranium. Toxicological Sciences. 2007;**98**(2): 458-468. DOI: 10.1093/toxsci/kfm132

[30] Tasat DR, de Rey BM. Cytotoxic effect of uranium dioxide on rat alveolar macrophages. Environmental Research. 1987;**44**:71-81. DOI: 10.1016/ s0013-9351(87)80087-7

[31] Orona NS, Tasat DR. Uranyl nitrateexposed rat alveolar macrophages cell death: Influence of superoxide anion and TNF α mediators. Toxicology and Applied Pharmacology. 2012;**261**(3):309-316. DOI: 10.1016/j. taap.2012.04.022

[32] Katz SA. The chemistry and toxicology of depleted uranium. Toxics. 2014;**2**:50-78. DOI: 10.3390/ toxics2010050 toxics. ISSN: 2305-6304

[33] Craft E, Abu-Qare A, Flaherty M, Garofolo M, Rincavage H, Abou-Donia M. Depleted and natural uranium: chemistry and toxicological effects. Journal of Toxicology and Environmental Health. Part B, Critical Reviews. 2004;**7**(4):297-317. DOI: 10.1080/10937400490452714

[34] Briner W. The toxicity of depleted uranium. International Journal of Environmental Research and Public Health. 2010;**7**:303-313. DOI: 10.3390/ ijerph7010303

[35] López R, Díaz Sylvester P, Ubios A, Cabrini R. Percutaneous toxicity of uranyl nitrate: Its effect in terms of exposure area and time. Health Physics. 2000;**78**(4):434-437. DOI: 10.1097/00004032-200004000-00007

[36] McDiarmid MA, Keogh JP, Hooper FJ, McPhaul K, Squibb K, Kane R, et al. Health effects of depleted uranium on exposed Gulf War veterans. Environmental Research. 2000;**82**(2):168-180. DOI: 10.1006/ enrs.1999.4012

[37] de Rey B, Lanfranchi H, Cabrini R. Deposition pattern and toxicity of subcutaneously implanted uranium dioxide in rats. Health Physics. 1984;**46**:688-692

[38] Voegtlin C, Hodge H. Pharmacology and Toxicology of Uranium Compounds (First edition). New York/London: McGraw Hill; 1949

[39] Stokinger H, Baxter R, Dygert H, et al. Toxicity following inhalation for 1 and 2 years. In: Voegtlin C, Hodge HC, editors. Pharmacology and Toxicology of Uranium Compounds. New York, NY: McGraw-Hill; 1953. pp. 1370-1776

[40] Domingo J, Llobet J, Tomás J, Corbella J. Acute toxicity of uranium in rats and mice. Bulletin of Environmental Contamination and Toxicology. 1987;**39**:168-174. DOI: 10.1007/bf01691806

[41] Martínez A, Mandalunis P, Bozal C, Cabrini R, Ubios A. Renal function in mice poisoned with oral uranium and treated with ethane-1 hydroxy-1,1-bisphosphonate (EHBP). Health Physics. 2003;**85**:343-347. DOI: 10.1097/00004032-200309000-00010

[42] Hodge H. Mechanism of uranium poisoning. In: Proceedings of the International Conference of the Peaceful Uses of Atomic Energy, Vol. 13; 1955. pp. 229-232

[43] Avasthi P, Evan A, Hay D. Glomerular endothelial cells in uranyl nitrate-induced acute renal failure in rats. The Journal of Clinical Investigation. 1980;**65**(1):121-127. DOI: 10.1172/JCI109641

[44] Haley D. Morphologic changes in uranyl nitrate-induced acute renal failure in saline- and water-drinking rats. Laboratory Investigation. 1982;**46**(2):196-208

[45] Haley D, Bulger R, Dobyan D. The long-term effects of uranyl nitrate on the structure and function of the rat kidney. Virchows Archiv. B, Cell Pathology Including Molecular Pathology. 1982;**41**(1-2):181-192. DOI: 10.1007/bf02890280

[46] Kobayashi S, Nagase M, Honda N, Hishida A, et al. Kidney International. 1984;**26**(6):808-815. DOI: 10.1038/ ki.1984.222

[47] Sangeetha Vijayan P, Rekha P, Dinesh U, Arun A. Biochemical and histopathological responses of the Swiss albino mice treated with uranyl nitrate and its recovery. Renal

**131**

*Bisphosphonates as Chelating Agents in Uranium Poisoning*

[56] Ubios A, Marzorati M, Cabrini R. Ultraestructural alterations of bone due to uranium intoxication. Journal of

Dental Research. 1992;**71**:973

1995;**8**:3-8

[57] Ubios A, Braun E, Cabrini R. Lethality due to uranium poisoning is prevented by ethane-1-hydroxy-1,1-bisphosphonate (EHBP). Health Physics. 1994;**66**:540-544. DOI: 10.1097/00004032-199405000-00005

[58] Ubios AM, Piloni MJ, Marzorati M, Cabrini RL. Bone growth is impaired by uranium intoxication. Acta Odontológica Latinoamericana.

[59] Pujadas Bigi M, Lemlich L, Mandalunis P, Ubios A. Exposure to oral uranyl nitrate delays tooth eruption and development. Health Physics. 2003;**84**(2):163-169. DOI: 10.1097/00004032-200302000-00003

[60] Tasat D, Orona N, Mandalunis P, Cabrini R, Ubios A. Ultrastructural and metabolic changes in osteoblasts exposed to uranyl nitrate. Archives of Toxicology. 2007;**81**(5):319-326. DOI:

10.1007/s00204-006-0165-2

[61] Ubios A, Guglielmotti M,

Steimetz T, Cabrini R. Uranium inhibits bone formation in physiologic alveolar bone modeling and remodeling.

Environmental Research. 1991;**54**:17-23. DOI: 10.1016/s0013-9351(05)80191-4

[62] Bozal C, Martinez A, Cabrini R,

hydroxy-1,1- bisphosphonate (EHBP) on endochondral ossification lesions induced by a lethal oral dose of uranyl nitrate. Archives of Toxicology. 2005;**79**:475-481. DOI: 10.1007/

Carle V, Lorivel T, Breuil V, Carle GF, Santucci-Darmanin S. Natural uranium impairs the differentiation and the

Ubios A. Effect of ethane-1-

[63] Gritsaenko T, Pierrefite-

s00204-005-0649-5

*DOI: http://dx.doi.org/10.5772/intechopen.92220*

Failure. 2016;**38**(5):770-775. DOI: 10.3109/0886022X.2016.1160248

[48] Adams N, Spoor N. Kidney and bone retention functions in the human metabolism of uranium. Physics in Medicine and Biology. 1974;**19**:460-471. DOI: 10.1088/0031-9155/19/4/004

[49] Neuman M, Neuman W. The deposition of uranium in bone; radioautographic studies. The Journal of Biological Chemistry.

[50] Rowland R, Farnham J. The deposition of uranium in bone. Health Physics. 1969;**17**:139-144. DOI: 10.1097/00004032-196907000-00015

[52] Neuman W, Neuman M,

in bone; animal studies. The Journal of Biological Chemistry.

1948;**175**(2):705-709

10.1007/bf01952392

0714.1985.tb00530.x

1987;**6**:357-366

[54] Guglielmotti M, Ubios A, Cabrini R. Alveolar wound healing alterations under uranyl nitrate

[55] Guglielmotti M, Ubios A, Cabrini R. Morphometric study of the effect of low dose of uranium on bone healing. Acta Stereologica.

[51] Kurttio P, Komulainen H, Leino A, Salonen L, Auvinen A, Saha H. Bone as a possible target of chemical toxicity of natural uranium in drinking water. Environmental Health Perspectives. 2005;**113**:68-72. DOI: 10.1289/ehp.7475

Mulryan B. The deposition of uranium

[53] Guglielmotti M, Ubios A, de Rey B, Cabrini R. Effects of acute intoxication with uranyl nitrate on bone formation. Experientia. 1984;**40**:474-476. DOI:

intoxication. Journal of Oral Pathology. 1985;**14**:565-572. DOI: 10.1111/j.1600-

1948;**175**(2):711-714

*Bisphosphonates as Chelating Agents in Uranium Poisoning DOI: http://dx.doi.org/10.5772/intechopen.92220*

Failure. 2016;**38**(5):770-775. DOI: 10.3109/0886022X.2016.1160248

[48] Adams N, Spoor N. Kidney and bone retention functions in the human metabolism of uranium. Physics in Medicine and Biology. 1974;**19**:460-471. DOI: 10.1088/0031-9155/19/4/004

[49] Neuman M, Neuman W. The deposition of uranium in bone; radioautographic studies. The Journal of Biological Chemistry. 1948;**175**(2):711-714

[50] Rowland R, Farnham J. The deposition of uranium in bone. Health Physics. 1969;**17**:139-144. DOI: 10.1097/00004032-196907000-00015

[51] Kurttio P, Komulainen H, Leino A, Salonen L, Auvinen A, Saha H. Bone as a possible target of chemical toxicity of natural uranium in drinking water. Environmental Health Perspectives. 2005;**113**:68-72. DOI: 10.1289/ehp.7475

[52] Neuman W, Neuman M, Mulryan B. The deposition of uranium in bone; animal studies. The Journal of Biological Chemistry. 1948;**175**(2):705-709

[53] Guglielmotti M, Ubios A, de Rey B, Cabrini R. Effects of acute intoxication with uranyl nitrate on bone formation. Experientia. 1984;**40**:474-476. DOI: 10.1007/bf01952392

[54] Guglielmotti M, Ubios A, Cabrini R. Alveolar wound healing alterations under uranyl nitrate intoxication. Journal of Oral Pathology. 1985;**14**:565-572. DOI: 10.1111/j.1600- 0714.1985.tb00530.x

[55] Guglielmotti M, Ubios A, Cabrini R. Morphometric study of the effect of low dose of uranium on bone healing. Acta Stereologica. 1987;**6**:357-366

[56] Ubios A, Marzorati M, Cabrini R. Ultraestructural alterations of bone due to uranium intoxication. Journal of Dental Research. 1992;**71**:973

[57] Ubios A, Braun E, Cabrini R. Lethality due to uranium poisoning is prevented by ethane-1-hydroxy-1,1-bisphosphonate (EHBP). Health Physics. 1994;**66**:540-544. DOI: 10.1097/00004032-199405000-00005

[58] Ubios AM, Piloni MJ, Marzorati M, Cabrini RL. Bone growth is impaired by uranium intoxication. Acta Odontológica Latinoamericana. 1995;**8**:3-8

[59] Pujadas Bigi M, Lemlich L, Mandalunis P, Ubios A. Exposure to oral uranyl nitrate delays tooth eruption and development. Health Physics. 2003;**84**(2):163-169. DOI: 10.1097/00004032-200302000-00003

[60] Tasat D, Orona N, Mandalunis P, Cabrini R, Ubios A. Ultrastructural and metabolic changes in osteoblasts exposed to uranyl nitrate. Archives of Toxicology. 2007;**81**(5):319-326. DOI: 10.1007/s00204-006-0165-2

[61] Ubios A, Guglielmotti M, Steimetz T, Cabrini R. Uranium inhibits bone formation in physiologic alveolar bone modeling and remodeling. Environmental Research. 1991;**54**:17-23. DOI: 10.1016/s0013-9351(05)80191-4

[62] Bozal C, Martinez A, Cabrini R, Ubios A. Effect of ethane-1 hydroxy-1,1- bisphosphonate (EHBP) on endochondral ossification lesions induced by a lethal oral dose of uranyl nitrate. Archives of Toxicology. 2005;**79**:475-481. DOI: 10.1007/ s00204-005-0649-5

[63] Gritsaenko T, Pierrefite-Carle V, Lorivel T, Breuil V, Carle GF, Santucci-Darmanin S. Natural uranium impairs the differentiation and the

resorbing function of osteoclasts. Biochimica et Biophysica Acta - General Subjects. 2017;**1861**(4):715-726. DOI: 10.1016/j.bbagen.2017.01.008

[64] Lawrence G, Patel K, Nusbaum A. Uranium toxicity and chelation therapy. Conference paper. Pure and Applied Chemistry. 2014;**86**(7):1105-1110. DOI: 10.1515/pac-2014-0109

[65] Cooper JR, Stradling GN, Smith H, Ham SE. The behaviour of uranium-233 oxide and uranyl-233 nitrate in rats. International Journal of Radiation Biology and Related Studies in Physics, Chemistry, and Medicine. 1982;**41**(4):421-433. DOI: 10.1080/09553008214550461

[66] Fisher D, Kathern R, Swint M. Modified biokinetic model for uranium from analysis of acute exposure of UF6. Health Physics. 1991;**60**(3):335-342. DOI: 10.1097/00004032-199103000-00002

[67] Domingo J, Colomina M, Llobet J, Jones M, Singh P, Campbell R. The action of chelating agents in experimental uranium intoxication in mice: Variation with structure and time of administration. Fundamental and Applied Toxicology. 1992;**19**:350-357. DOI: 10.1016/0272-0590(92)90173-f

[68] Ortega A, Domingo J, Gomez M, Corbella J. Treatment of experimental acute uranium poisoning by chelating agents. Pharmacology and Toxicology. 1989;**64**:247-251. DOI: 10.1111/j.1600- 0773.1989.tb00640.x

[69] Stradling G, Gray S, Moody J, Ellender M. Efficacy of Tiron for enhancing the excretion of uranium from the rat. Human & Experimental Toxicology. 1991;**10**(3):195-198. DOI: 10.1177/096032719101000308

[70] Ubios A, Guglielmotti M, Cabrini R. Effects of diphosphonates on the prevention of X radiation induced inhibition of bone formation in rats.

Journal of Oral Pathology. 1986;**15**:500- 505. DOI: 10.1111/j.1600-0714.1986. tb00666.x

[71] Guglielmotti M, Ubios A, Larumbe J, Cabrini R. Tetracycline in uranyl nitrate intoxication: Its action on renal damage and uranium retention in bone. Health Physics. 1989;**57**:403-405. DOI: 10.1097/00004032-198909000-00005

[72] Ubios A, Guglielmotti M, Cabrini R. Ethane 1-hydroxy-1, 1-diphosphonate (EHDP) counteracts the inhibitory effect of uranyl nitrate on bone formation. Archives of Environmental Health. 1990;**45**(6):374-377. DOI: 10.1080/00039896.1990.10118758

[73] Fleisch H, Bisaz S. Isolation from urine of pyrophosphate, a calcification inhibitor. The American Journal of Physiology. 1962;**203**:671-675. DOI: 10.1152/ajplegacy.1962.203.4.671

[74] Catsch A. Effect of some chelating agents on acute toxicity of uranyl nitrate. Klinische Wochenschrift. 1959;**37**(12):657-660. DOI: 10.1007/ bf01478404

[75] Ubios A, Braun EM, Cabrini R. Effect of bisphosphonates on abnormal mandibular growth of rats intoxicated with uranium. Health Physics. 1998;**75**(6):610-613. DOI: 10.1097/00004032-199812000-00004

[76] Basinger MA, Jones MM. Tiron (sodium 4,5-dihydroxybenzene-1,3 disulfonate) as an antidote for acute uranium intoxication in mice. Research Communications in Chemical Pathology and Pharmacology. 1981;**34**(2):351-357

[77] Basinger MA, Forti RL, Burka LT, Jones MM, Mitchell WM, Johnson JE, et al. Phenolic chelating agents as antidotes for acute uranyl acetate intoxication in mice. Journal of Toxicology and Environmental Health. 1983;**11**:237-246

**133**

**Chapter 9**

**Abstract**

structure.

**1. Introduction**

*Eugenia Malchukova*

Inf luence of the Doping Ion

Nature and Content on Defect

Effect of Ionizing Radiation in

Effects of ionizing irradiation on defect creation processes have been studied in rare earth (RE)-doped (RE = Sm, Gd, Eu, Ce, Nd) aluminoborosilicate glass with use of the electron paramagnetic resonance (EPR) and optical spectroscopy. As a function of RE ion nature, we observe that doping significantly influences the nature of the defects produced during irradiation and more specifically the relative proportions between hole and electron defect centers. Strong decrease of defect production efficiency under ionizing radiation independence on both the RE doping content and on the relative stability of the RE different oxidation states is also clearly revealed. The results could be explained by dynamical reversible trapping of the electron-hole pairs produced during irradiation on the different RE charge states as well as by RE segregation and pre-existing defects speciation in ABS glass

Creation Processes under the

Aluminoborosilicate Glasses

**Keywords:** borosilicate, glasses, EPR, luminescence, irradiation, defects

Irradiation effects are an active research field in amorphous silica (aSiO2) due to many technological applications requiring a good maintenance of transparency (e.g. fibers, laser optics and radioactive environments) [1–4]. Indeed for aSiO2, the optical properties are controlled by the nature and the content of defect produced during an ionizing radiation (laser, X, γ, electrons) [5–7]. Different works using Electron Paramagnetic Spectroscopy (EPR) and optical absorption have shown that two different defects production processes occur during ionizing irradiation. The first process called intrinsic defects production [8–10] is correlated to Si–O bonds breaking leading to well-known paramagnetic E′ and Non-Bridging Oxygen Hole Centers (NBOHC) with self-trap excitons acting as possible precursors [11–13]. Peroxy radicals (POR) paramagnetic defect can also be produced with intrinsic process by the displacement of oxygen into an interstitial position like Frenkel defects [12, 14]. The second defect creation process is called "extrinsic" and is correlated to the presence of different impurities (H, Cl, Transition metals, Rare earth, …) inside

#### **Chapter 9**

## Inf luence of the Doping Ion Nature and Content on Defect Creation Processes under the Effect of Ionizing Radiation in Aluminoborosilicate Glasses

*Eugenia Malchukova*

#### **Abstract**

Effects of ionizing irradiation on defect creation processes have been studied in rare earth (RE)-doped (RE = Sm, Gd, Eu, Ce, Nd) aluminoborosilicate glass with use of the electron paramagnetic resonance (EPR) and optical spectroscopy. As a function of RE ion nature, we observe that doping significantly influences the nature of the defects produced during irradiation and more specifically the relative proportions between hole and electron defect centers. Strong decrease of defect production efficiency under ionizing radiation independence on both the RE doping content and on the relative stability of the RE different oxidation states is also clearly revealed. The results could be explained by dynamical reversible trapping of the electron-hole pairs produced during irradiation on the different RE charge states as well as by RE segregation and pre-existing defects speciation in ABS glass structure.

**Keywords:** borosilicate, glasses, EPR, luminescence, irradiation, defects

#### **1. Introduction**

Irradiation effects are an active research field in amorphous silica (aSiO2) due to many technological applications requiring a good maintenance of transparency (e.g. fibers, laser optics and radioactive environments) [1–4]. Indeed for aSiO2, the optical properties are controlled by the nature and the content of defect produced during an ionizing radiation (laser, X, γ, electrons) [5–7]. Different works using Electron Paramagnetic Spectroscopy (EPR) and optical absorption have shown that two different defects production processes occur during ionizing irradiation. The first process called intrinsic defects production [8–10] is correlated to Si–O bonds breaking leading to well-known paramagnetic E′ and Non-Bridging Oxygen Hole Centers (NBOHC) with self-trap excitons acting as possible precursors [11–13]. Peroxy radicals (POR) paramagnetic defect can also be produced with intrinsic process by the displacement of oxygen into an interstitial position like Frenkel defects [12, 14]. The second defect creation process is called "extrinsic" and is correlated to the presence of different impurities (H, Cl, Transition metals, Rare earth, …) inside

aSiO2 materials [8, 15–18]. In that case, the nature of different possible irradiation paramagnetic defects produced (E′, NBOHC, and POR) does not differ but an higher defect production efficiency is observed associated to saturation processes of defect content depending on impurities nature and content, respectively [19]. Defects production processes in aSiO2 are therefore mainly controlled by the nature and the content of the different impurities.

For more complex oxide glass compositions, the presence of network modifiers ions (Na+ , K+ , Ca2+) and other network formers ions (B3+, Al3+) stabilizes with an high efficiency different hole trap like Boron-Oxygen Hole Center (BOHC) [20, 21], Aluminum-Oxygen Hole Center (AlOHC) [22] or Hole trapped defects on Non-Bridging Oxygen (NBO) called HC1, HC2 centers [23, 24]. In addition, the literature shows that the content of electron trap defects like E′ centers and equivalent defects closed to B3+ (BEC center) and Al3+ ions are generally much more lower than hole trap defects content for all oxide glass compositions including silica. Electron trapping on glass impurities like Hydrogen, alkaline, Transition Metals (TM), or Rare Earth (RE) ions could explain differences between the content of hole and electron trapped defects produced during exposure to ionizing radiation [7, 15]. In general for oxide glasses like borosilicate, silicate, and aluminosilicate, the nature and content of different paramagnetic defects observed by EPR spectroscopy will depend on the relative proportion of different network formers (Si4+, Al3+, and B3+) and on network modifiers contents introduced inside the oxide glass. In case of aluminoborosilicate (ABS) glasses studied in this work, the nature and proportion of different paramagnetic defects have been previously determined using the simulation of EPR spectra of different β-irradiated borosilicate glass samples [25].

Doping processes of oxide glasses with rare earth (RE) ions influence a lot the nature and the content of different paramagnetic defects produced during exposure to ionizing radiation. In case of Sm- [26], Gd- [27], and Yb- [28] doped borosilicate glass compositions, the first effect of doping is the decrease of total paramagnetic defect contents produced during irradiation to one integrated dose. Moreover for Fe-doped soda-lime glasses [29] and Cr-doped silicate glasses [30], a complete disappearance of the different paramagnetic defects is observed for doping level around 1 mol. %. Associated to the decrease of paramagnetic defects production efficiency with the doping ion content, the decrease of different structural changes under irradiation detected by Raman spectroscopy [29, 30], (increase of polymerization and the molecular oxygen production, and decrease of Si–O–Si average angle) are also observed at integrated dose higher than 109 Gy. Structural changes in glasses under the effect of ionizing radiation are mainly controlled by alkaline mobility in both network modifiers and charge compensator positions [31]. This result shows therefore strong relationships between the nature and contents of doping ions, irradiation defects creation processes, and the structural changes due to ionizing radiation exposure in oxide glasses.

However, these previous studies have mainly focused on the modification of the total paramagnetic defect concentration produced during ionizing radiation as a function of the doping ion nature and content. The goal of this chapter is to systematically present the paramagnetic irradiation defect creation processes in rare earth-doped oxide glasses. First, the influence of RE doping ion nature on the relative paramagnetic defect proportion observed by EPR spectroscopy in the same ABS glass composition will be considered. Then, the influence of both doping ion content and integrated radiation dose on the nature, content, and relative proportion of the different paramagnetic defects produced during ionizing radiation will be considered also. It is known, that the optical spectroscopy is most useful in cases where EPR techniques are not applicable and for diamagnetic defects. Also, transmission and luminescence experiments will be carried out in order to provide additional information

**135**

**Table 1.**

*RE doping concentration.*

*Influence of the Doping Ion Nature and Content on Defect Creation Processes under the Effect…*

on RE doping effect on ABS glass structure. This approach could improve our knowledge about defect creation processes under irradiation for ion doped oxide glasses. For that purpose, different RE-doped ABS glasses (RE = Sm, Gd, Eu, Ce, and Nd where the RE doping level between 0.1 and 1 mol. %) have been irradiated to different doses

Gy using a Van de Graaff accelerator.

Rare earth-doped ABS glasses were prepared by adding to the base glass with the following composition—59.77% SiO2, 4.00% Al2O3, 22.41% B2O3, 12.12% Na2O, and 1.70% ZrO2 (in mol. %)—different amounts of doping ions. The doping content of RE oxide considered in this work is shown in **Table 1**. The dried mixed powders were heated at 750°C for 10 h in air in a Pt crucible and melted at 1500°C for 2 h, then quenched on a copper plate. Before cutting, annealing at 500°C for 1–2 h was necessary to remove the internal stress. Samples were polished on a hand grinding wheel with a silicon carbide abrasive having the average grain size of 10 μm (1000 grain) to achieve the average thickness of 0.56 ± 0.05 mm. Each glass was analyzed by X-ray diffraction, in order to confirm the amorphous characteristics of the glass. All glasses were β-irradiated with 2.5 MeV electrons (10 μA) provided by a Van de Graaff accelerator (LSI, Palaiseau, France) at different integrated doses from 106

Gy. The used sample thickness made it possible to obtain uniform irradia-

Tesla of amplitude modulation and an applied microwave

tion on the entire glass volume. EPR measurements were conducted at room temperature on a X band (ν = 9.420 GHz) EMX Brücker EPR spectrometer using a 100 kHz

power of 1 mW. The EPR spectra of all irradiated RE-doped ABS glasses have been normalized to the same receiver gain and to a 100 mg sample weight. Paramagnetic defects total content has been estimated by the area under the defect absorbance EPR spectrum. A maximum error of 10% has been considered in this work taking into account uncertainties in the irradiated glass samples weight measurement, the sample positioning inside spectrometer cavity and defect absorbance EPR spectrum area computation or EPR line intensity measurement. The optical transmission spectra were measured on an Agilent Varian Cary 5000 spectrophotometer in 1 nm steps in the range of 200–1500 nm. The photoluminescence was analyzed by a SHAMROCK spectrograph F5303 mm: 150 lines/mm grating and a 400 mm slit combined with an ANDOR Istar (Andor Company, Belfast, U.K.) intensified charge coupled device. The 266 nm wavelength pulses width of around 8 ns and laser repetition rate of 10 Hz of an INDI Nd:YAG pulsed laser spectra physics were used for the PL excitation. The laser beam is transported via two mirrors, two lenses, and three diaphragms to the sample center with a final diameter of 2 mm. The pulse

*DOI: http://dx.doi.org/10.5772/intechopen.92317*

and 2 × 109

**2. Experimental part**

between 105

to 2 × 109

field modulation, 3 × 10<sup>−</sup><sup>4</sup>

on RE doping effect on ABS glass structure. This approach could improve our knowledge about defect creation processes under irradiation for ion doped oxide glasses. For that purpose, different RE-doped ABS glasses (RE = Sm, Gd, Eu, Ce, and Nd where the RE doping level between 0.1 and 1 mol. %) have been irradiated to different doses between 105 and 2 × 109 Gy using a Van de Graaff accelerator.

#### **2. Experimental part**

*Recent Techniques and Applications in Ionizing Radiation Research*

spectra of different β-irradiated borosilicate glass samples [25].

angle) are also observed at integrated dose higher than 109

to ionizing radiation exposure in oxide glasses.

content of the different impurities.

ions (Na+

, K+

aSiO2 materials [8, 15–18]. In that case, the nature of different possible irradiation paramagnetic defects produced (E′, NBOHC, and POR) does not differ but an higher defect production efficiency is observed associated to saturation processes of defect content depending on impurities nature and content, respectively [19]. Defects production processes in aSiO2 are therefore mainly controlled by the nature and the

For more complex oxide glass compositions, the presence of network modifiers

high efficiency different hole trap like Boron-Oxygen Hole Center (BOHC) [20, 21], Aluminum-Oxygen Hole Center (AlOHC) [22] or Hole trapped defects on Non-Bridging Oxygen (NBO) called HC1, HC2 centers [23, 24]. In addition, the literature shows that the content of electron trap defects like E′ centers and equivalent defects closed to B3+ (BEC center) and Al3+ ions are generally much more lower than hole trap defects content for all oxide glass compositions including silica. Electron trapping on glass impurities like Hydrogen, alkaline, Transition Metals (TM), or Rare Earth (RE) ions could explain differences between the content of hole and electron trapped defects produced during exposure to ionizing radiation [7, 15]. In general for oxide glasses like borosilicate, silicate, and aluminosilicate, the nature and content of different paramagnetic defects observed by EPR spectroscopy will depend on the relative proportion of different network formers (Si4+, Al3+, and B3+) and on network modifiers contents introduced inside the oxide glass. In case of aluminoborosilicate (ABS) glasses studied in this work, the nature and proportion of different paramagnetic defects have been previously determined using the simulation of EPR

Doping processes of oxide glasses with rare earth (RE) ions influence a lot the nature and the content of different paramagnetic defects produced during exposure to ionizing radiation. In case of Sm- [26], Gd- [27], and Yb- [28] doped borosilicate glass compositions, the first effect of doping is the decrease of total paramagnetic defect contents produced during irradiation to one integrated dose. Moreover for Fe-doped soda-lime glasses [29] and Cr-doped silicate glasses [30], a complete disappearance of the different paramagnetic defects is observed for doping level around 1 mol. %. Associated to the decrease of paramagnetic defects production efficiency with the doping ion content, the decrease of different structural changes under irradiation detected by Raman spectroscopy [29, 30], (increase of polymerization and the molecular oxygen production, and decrease of Si–O–Si average

in glasses under the effect of ionizing radiation are mainly controlled by alkaline mobility in both network modifiers and charge compensator positions [31]. This result shows therefore strong relationships between the nature and contents of doping ions, irradiation defects creation processes, and the structural changes due

However, these previous studies have mainly focused on the modification of the total paramagnetic defect concentration produced during ionizing radiation as a function of the doping ion nature and content. The goal of this chapter is to systematically present the paramagnetic irradiation defect creation processes in rare earth-doped oxide glasses. First, the influence of RE doping ion nature on the relative paramagnetic defect proportion observed by EPR spectroscopy in the same ABS glass composition will be considered. Then, the influence of both doping ion content and integrated radiation dose on the nature, content, and relative proportion of the different paramagnetic defects produced during ionizing radiation will be considered also. It is known, that the optical spectroscopy is most useful in cases where EPR techniques are not applicable and for diamagnetic defects. Also, transmission and luminescence experiments will be carried out in order to provide additional information

Gy. Structural changes

, Ca2+) and other network formers ions (B3+, Al3+) stabilizes with an

**134**

Rare earth-doped ABS glasses were prepared by adding to the base glass with the following composition—59.77% SiO2, 4.00% Al2O3, 22.41% B2O3, 12.12% Na2O, and 1.70% ZrO2 (in mol. %)—different amounts of doping ions. The doping content of RE oxide considered in this work is shown in **Table 1**. The dried mixed powders were heated at 750°C for 10 h in air in a Pt crucible and melted at 1500°C for 2 h, then quenched on a copper plate. Before cutting, annealing at 500°C for 1–2 h was necessary to remove the internal stress. Samples were polished on a hand grinding wheel with a silicon carbide abrasive having the average grain size of 10 μm (1000 grain) to achieve the average thickness of 0.56 ± 0.05 mm. Each glass was analyzed by X-ray diffraction, in order to confirm the amorphous characteristics of the glass.

All glasses were β-irradiated with 2.5 MeV electrons (10 μA) provided by a Van de Graaff accelerator (LSI, Palaiseau, France) at different integrated doses from 106 to 2 × 109 Gy. The used sample thickness made it possible to obtain uniform irradiation on the entire glass volume. EPR measurements were conducted at room temperature on a X band (ν = 9.420 GHz) EMX Brücker EPR spectrometer using a 100 kHz field modulation, 3 × 10<sup>−</sup><sup>4</sup> Tesla of amplitude modulation and an applied microwave power of 1 mW. The EPR spectra of all irradiated RE-doped ABS glasses have been normalized to the same receiver gain and to a 100 mg sample weight. Paramagnetic defects total content has been estimated by the area under the defect absorbance EPR spectrum. A maximum error of 10% has been considered in this work taking into account uncertainties in the irradiated glass samples weight measurement, the sample positioning inside spectrometer cavity and defect absorbance EPR spectrum area computation or EPR line intensity measurement. The optical transmission spectra were measured on an Agilent Varian Cary 5000 spectrophotometer in 1 nm steps in the range of 200–1500 nm. The photoluminescence was analyzed by a SHAMROCK spectrograph F5303 mm: 150 lines/mm grating and a 400 mm slit combined with an ANDOR Istar (Andor Company, Belfast, U.K.) intensified charge coupled device. The 266 nm wavelength pulses width of around 8 ns and laser repetition rate of 10 Hz of an INDI Nd:YAG pulsed laser spectra physics were used for the PL excitation. The laser beam is transported via two mirrors, two lenses, and three diaphragms to the sample center with a final diameter of 2 mm. The pulse


**Table 1.** *RE doping concentration.*

energy on the sample was ~2 mJ/pulse. The spectral measurements were carried out using different delay time (d) and gate width (G).

#### **3. EPR spectra of RE-doped ABS glass: b-irradiation dose effect**

Without doping, the nature of the different defects produced by ionizing radiation has been previously studied in the non-doped ABS glass composition irradiated with 2.5 MeV electrons by the simulation of the EPR spectra of irradiated samples annealed at different temperatures [25]. The EPR of the non-doped ABS glass irradiated at 1.3 × 108 Gy is presented in **Figure 1**. The main component of these EPR spectra is associated to the hyperfine structure with 11B (I = 3/2). The defect is called the Boron-Oxygen Hole Center (BOHC) (g1 = 2.0029, g2 = 2.0115, and g3 = 2.0500) and it is attributed to a hole trap on an oxygen link to a boron atom [21]. The second hole center for this glass composition that can be observed at high annealing temperature is the peroxy radical (Si–O–O°) named Oxy defect (g1 = 2.0024, g2 = 2.0110, and g3 = 2.0439) in the literature for silicate glasses [22]. The last hole center determined by the simulation of the EPR spectra for this glass composition is the HC1 center attributed to a hole trapped on a non-bridging oxygen in the vicinity of alkaline ion. Finally, the EPR line around g = 2.0011 is an electron trap and is attributed to the well-known E′ center [11].

**Figure 1** presents the EPR spectra recorded at room temperature of the non-doped and 0.1 mol% RE-doped ABS glasses (RE = Sm, Gb, Eu, Nd, and 0.2 mol% Ce) irradiated with 2.5 MeV electrons (integrated dose of 1.3 × 108 Gy). First, It can be observed

**Figure 1.**

*X band EPR spectra of the lowest RE-doped ABS glasses (RE = Gd, Sm, Eu, Ce, and Nd) irradiated at 1.3 × 108 Gy.*

**137**

irradiation.

**Figure 2.**

on **Figure 2a** and **b**, respectively.

*Influence of the Doping Ion Nature and Content on Defect Creation Processes under the Effect…*

clearly on that figure that RE doping at low level (0.1 mol%) influences significantly both the amount of defect produced during irradiation and their relative proportions. More specifically, a decrease of the different hole centers (HC) is analyzed depending on the nature of the doping ion ([HC]Eu > [HC]Sm > [HC]Nd > [HC]Ce). This effect is maximum for 0.2 mol% Ce-doped glasses where the content of hole centers is drastically decreasing in comparison with the non-doped glass composition. For E′ center detected at g = 2.0011 in the non-doped ABS glass, a strong increase as a function of the RE doping ion nature is observed ([E′]Eu < [E′]Sm < [E′]Nd < [E′]Ce). However, for all ABS glass compositions studied, the quantity of electron defect centers (E′) remains smaller than the hole defect centers (BOHC, OXY, HC1) showing therefore the presence of other mechanisms acting as traps for the electrons produced during

*Evolution of EPR defects content as a function of integrated dose for the lowest: (a) and the highest; (b)* 

*concentration of RE doping of β−irradiated ABS glass (RE = Gd, Sm, Eu, Ce, and Nd).*

Evolution of the total paramagnetic defect content for all RE-doped glasses (RE = Sm, Gd, Eu, Nd, and Ce) as a function of the integrated dose is presented in logarithmic scales on **Figure 2** for two different RE doping levels: 0.1 and 1 mol%,

For non-doped ABS glass, the total defect concentration is increasing with the integrated dose. This behavior can be correlated with extrinsic and/or intrinsic defect creation processes under the effect of ionizing radiation [8]. Two effects can be observed in **Figure 2a** and **b**. First, the decrease of the defect produced during irradiation at one integrated dose depending on the nature of the RE doping ion. The second effect is saturation behavior of the defect content as a function of the integrated dose associated to a decrease of the defect content at higher doses for all RE-doped glasses. We can therefore conclude that glass doping processes play an important role on defect creation processes under the effect of ionizing radiation.

The influence of RE content on defect production under irradiation is shown in **Figure 3a** and **b** for two different integrated doses. For all RE doping considered in this work, the defect content is decreasing as a function of the RE doping content

In addition, the relative proportions between the different paramagnetic defects observed by EPR spectroscopy are modified by both the nature of the RE ion and also its content in the host glasses. These effects can be seen on **Figures 4–7** showing

Gy) glass samples doped with

**4. EPR spectra of RE-doped ABS glass: RE concentration effect**

inside the glass but with different efficiency depending on the RE nature.

the normalized EPR spectra of irradiated (1.3 × 108

*DOI: http://dx.doi.org/10.5772/intechopen.92317*

*Influence of the Doping Ion Nature and Content on Defect Creation Processes under the Effect… DOI: http://dx.doi.org/10.5772/intechopen.92317*

**Figure 2.**

*Recent Techniques and Applications in Ionizing Radiation Research*

ated with 2.5 MeV electrons (integrated dose of 1.3 × 108

using different delay time (d) and gate width (G).

ated at 1.3 × 108

well-known E′ center [11].

energy on the sample was ~2 mJ/pulse. The spectral measurements were carried out

Without doping, the nature of the different defects produced by ionizing radiation has been previously studied in the non-doped ABS glass composition irradiated with 2.5 MeV electrons by the simulation of the EPR spectra of irradiated samples annealed at different temperatures [25]. The EPR of the non-doped ABS glass irradi-

tra is associated to the hyperfine structure with 11B (I = 3/2). The defect is called the Boron-Oxygen Hole Center (BOHC) (g1 = 2.0029, g2 = 2.0115, and g3 = 2.0500) and it is attributed to a hole trap on an oxygen link to a boron atom [21]. The second hole center for this glass composition that can be observed at high annealing temperature is the peroxy radical (Si–O–O°) named Oxy defect (g1 = 2.0024, g2 = 2.0110, and g3 = 2.0439) in the literature for silicate glasses [22]. The last hole center determined by the simulation of the EPR spectra for this glass composition is the HC1 center attributed to a hole trapped on a non-bridging oxygen in the vicinity of alkaline ion. Finally, the EPR line around g = 2.0011 is an electron trap and is attributed to the

**Figure 1** presents the EPR spectra recorded at room temperature of the non-doped and 0.1 mol% RE-doped ABS glasses (RE = Sm, Gb, Eu, Nd, and 0.2 mol% Ce) irradi-

*X band EPR spectra of the lowest RE-doped ABS glasses (RE = Gd, Sm, Eu, Ce, and Nd) irradiated at* 

Gy). First, It can be observed

Gy is presented in **Figure 1**. The main component of these EPR spec-

**3. EPR spectra of RE-doped ABS glass: b-irradiation dose effect**

**136**

**Figure 1.**

*1.3 × 108 Gy.*

*Evolution of EPR defects content as a function of integrated dose for the lowest: (a) and the highest; (b) concentration of RE doping of β−irradiated ABS glass (RE = Gd, Sm, Eu, Ce, and Nd).*

clearly on that figure that RE doping at low level (0.1 mol%) influences significantly both the amount of defect produced during irradiation and their relative proportions. More specifically, a decrease of the different hole centers (HC) is analyzed depending on the nature of the doping ion ([HC]Eu > [HC]Sm > [HC]Nd > [HC]Ce). This effect is maximum for 0.2 mol% Ce-doped glasses where the content of hole centers is drastically decreasing in comparison with the non-doped glass composition. For E′ center detected at g = 2.0011 in the non-doped ABS glass, a strong increase as a function of the RE doping ion nature is observed ([E′]Eu < [E′]Sm < [E′]Nd < [E′]Ce). However, for all ABS glass compositions studied, the quantity of electron defect centers (E′) remains smaller than the hole defect centers (BOHC, OXY, HC1) showing therefore the presence of other mechanisms acting as traps for the electrons produced during irradiation.

Evolution of the total paramagnetic defect content for all RE-doped glasses (RE = Sm, Gd, Eu, Nd, and Ce) as a function of the integrated dose is presented in logarithmic scales on **Figure 2** for two different RE doping levels: 0.1 and 1 mol%, on **Figure 2a** and **b**, respectively.

For non-doped ABS glass, the total defect concentration is increasing with the integrated dose. This behavior can be correlated with extrinsic and/or intrinsic defect creation processes under the effect of ionizing radiation [8]. Two effects can be observed in **Figure 2a** and **b**. First, the decrease of the defect produced during irradiation at one integrated dose depending on the nature of the RE doping ion. The second effect is saturation behavior of the defect content as a function of the integrated dose associated to a decrease of the defect content at higher doses for all RE-doped glasses. We can therefore conclude that glass doping processes play an important role on defect creation processes under the effect of ionizing radiation.

#### **4. EPR spectra of RE-doped ABS glass: RE concentration effect**

The influence of RE content on defect production under irradiation is shown in **Figure 3a** and **b** for two different integrated doses. For all RE doping considered in this work, the defect content is decreasing as a function of the RE doping content inside the glass but with different efficiency depending on the RE nature.

In addition, the relative proportions between the different paramagnetic defects observed by EPR spectroscopy are modified by both the nature of the RE ion and also its content in the host glasses. These effects can be seen on **Figures 4–7** showing the normalized EPR spectra of irradiated (1.3 × 108 Gy) glass samples doped with

**Figure 3.**

*Evolution of EPR defects concentration as a function of the RE doping ion content in ABS glasses β−irradiated at 6.5 × 106 : (a) and 2.6 × 109 Gy; (b) RE = Gd, Sm, Eu, Ce, and Nd.*

**Figure 4.**

*X band EPR spectra recorded at room temperature of 0.2, 0.4, 1.2, and 2 mol.% CeO2-doped ABS glass irradiated at 1.3 × 108 Gy (the EPR spectra have been normalized to E′ EPR line intensity): (a) and X band EPR spectra of 0.2 and 2 mol.%CeO2-doped ABS glass irradiated at 2 × 109 Gy (b).*

Ce, Eu, Sm, and Nd ions, respectively. From the **Figure 4a** one can see the strongest influence of doping on defect production in Ce-doped glasses: a huge decreased of different holes centers (BOHC, OXY, HC1) in the defect EPR spectrum is observed starting from the lowest doping level considered in this work (0.2 mol.% of CeO2). The BOHC center becomes undetectable in the EPR spectra at Cerium doping levels higher than 0.2 mol.% and the hole defects remaining in the EPR spectra is the OXY and HC1 centers as it is shown in **Figure 4b** for the Ce-doped ABS glass irradiated at 2 × 109 Gy (arrows in **Figure 4b**). This effect is more pronounced in the case of the highest doses (more than 109 Gy). From **Figure 5a** and **b**, it can be concluded that Ce doping strongly inhibits the defect production observed by EPR spectroscopy and in addition stops the different holes defects production under the effect of ionizing radiation. BOHC defect is also detected.

When comparing these results with Eu-doping in the same ABS glass composition, similar effects of doping ion content on defect production efficiency are observed by EPR spectroscopy (**Figure 5**). But in the case of Eu-doping, a

**139**

**Figure 6.**

*irradiated at 1.3 × 108*

**Figure 5.**

*irradiated at 1.3 × 108*

*Influence of the Doping Ion Nature and Content on Defect Creation Processes under the Effect…*

*X band EPR spectra recorded at room temperature of 0.1, 0.2, 0.5, and 1 mol.% Eu2O3-doped ABS glass* 

*band EPR spectra of 0.1 and 1 mol.% Eu2O3-doped ABS glass irradiated at 2 × 109*

 *Gy (the EPR spectra have been normalized to BOHC EPR line intensity) (a) and X* 

 *Gy (b).*

strong decrease of E′ centers contribution in the defect EPR spectra can be seen (**Figure 5a**). The E′ center becomes undetectable in the EPR spectra at Europium doping levels higher than 0.6 mol.% and the hole defects re-arrangement in the EPR spectra between OXY and BOHC centers can be observed. The highest irradiation dose results in more re-arrangement of hole defects as can be seen from **Figure 5b** (arrows in the **Figure 5b**). The influence of Sm- (**Figure 6**) and Nd- (**Figure 7**) doping contents are weaker than for Ce-doped ABS glasses for both the decrease in

*X band EPR spectra recorded at room temperature of 0.1, 0.2, 0.4, 0.6, and 1 mol.% Sm2O3-doped ABS glass* 

 *Gy (the EPR spectra have been normalized to BOHC EPR line intensity).*

*DOI: http://dx.doi.org/10.5772/intechopen.92317*

*Influence of the Doping Ion Nature and Content on Defect Creation Processes under the Effect… DOI: http://dx.doi.org/10.5772/intechopen.92317*

**Figure 5.**

*Recent Techniques and Applications in Ionizing Radiation Research*

Ce, Eu, Sm, and Nd ions, respectively. From the **Figure 4a** one can see the strongest influence of doping on defect production in Ce-doped glasses: a huge decreased of different holes centers (BOHC, OXY, HC1) in the defect EPR spectrum is observed starting from the lowest doping level considered in this work (0.2 mol.% of CeO2). The BOHC center becomes undetectable in the EPR spectra at Cerium doping levels higher than 0.2 mol.% and the hole defects remaining in the EPR spectra is the OXY and HC1 centers as it is shown in **Figure 4b** for the Ce-doped ABS glass irradiated at

 *Gy (the EPR spectra have been normalized to E′ EPR line intensity): (a) and X band* 

*X band EPR spectra recorded at room temperature of 0.2, 0.4, 1.2, and 2 mol.% CeO2-doped ABS glass* 

*EPR spectra of 0.2 and 2 mol.%CeO2-doped ABS glass irradiated at 2 × 109*

*Evolution of EPR defects concentration as a function of the RE doping ion content in ABS glasses β−irradiated* 

 *Gy; (b) RE = Gd, Sm, Eu, Ce, and Nd.*

Gy (arrows in **Figure 4b**). This effect is more pronounced in the case of the

Ce doping strongly inhibits the defect production observed by EPR spectroscopy and in addition stops the different holes defects production under the effect of ion-

When comparing these results with Eu-doping in the same ABS glass composition, similar effects of doping ion content on defect production efficiency are observed by EPR spectroscopy (**Figure 5**). But in the case of Eu-doping, a

Gy). From **Figure 5a** and **b**, it can be concluded that

 *Gy (b).*

**138**

2 × 109

**Figure 4.**

*irradiated at 1.3 × 108*

**Figure 3.**

*at 6.5 × 106*

*: (a) and 2.6 × 109*

highest doses (more than 109

izing radiation. BOHC defect is also detected.

*X band EPR spectra recorded at room temperature of 0.1, 0.2, 0.5, and 1 mol.% Eu2O3-doped ABS glass irradiated at 1.3 × 108 Gy (the EPR spectra have been normalized to BOHC EPR line intensity) (a) and X band EPR spectra of 0.1 and 1 mol.% Eu2O3-doped ABS glass irradiated at 2 × 109 Gy (b).*

**Figure 6.**

*X band EPR spectra recorded at room temperature of 0.1, 0.2, 0.4, 0.6, and 1 mol.% Sm2O3-doped ABS glass irradiated at 1.3 × 108 Gy (the EPR spectra have been normalized to BOHC EPR line intensity).*

strong decrease of E′ centers contribution in the defect EPR spectra can be seen (**Figure 5a**). The E′ center becomes undetectable in the EPR spectra at Europium doping levels higher than 0.6 mol.% and the hole defects re-arrangement in the EPR spectra between OXY and BOHC centers can be observed. The highest irradiation dose results in more re-arrangement of hole defects as can be seen from **Figure 5b** (arrows in the **Figure 5b**). The influence of Sm- (**Figure 6**) and Nd- (**Figure 7**) doping contents are weaker than for Ce-doped ABS glasses for both the decrease in

#### **Figure 7.**

*X band EPR spectra recorded at room temperature of 0.1, 0.2, 0.6, and 1 mol.% Nd2O3-doped ABS glass irradiated at 1.3 × 108 Gy (the EPR spectra have been normalized to BOHC EPR line intensity).*

defect production efficiencies and the changes in the relative proportions of defects composing the EPR spectra of these irradiated glass samples. However, a decrease in the relative proportion of the different defect holes centers (BOHC, Oxy, HC1) for the different Nd-doped ABS glasses (**Figure 7**) can be observed.

This effect could also be correlated to the evolution analyzed for Ce-doped ABS glasses. The changes of the relative proportions of defect as a function of Sm-doping content in ABS glasses (**Figure 6**) show mainly the decrease of E′ defect component in the EPR spectra. Associated to this decrease, an increase in the relative proportion of OXY center relative to relative to BOHC defect is also detected.

The experiments testify that glass doping processes can influence the proportion between different defects produced during irradiation compared to the non-doped glass composition. This change has been usually correlated to the capacity of the doping ion to act as a trap for the holes and electrons produced during irradiation. Eu3+ ions are known to be good electron traps and one can observe on **Figures 1** and **5a** the strong decrease of the E′ proportion relatively to the non-doped ABS glasses. Sm3+ ion can also be reduced during the exposure to ionizing radiation but with a weaker efficiency than Eu3+ ions, this effect is also observed on the decrease of the relative proportion of E′ centers in the defect EPR spectra (**Figures 1** and **6**). By contrast, Ce3+ ions produced during irradiation or during the synthesis of Ce-doped glasses is a well-known hole traps [32, 33]. So these ions (Eu3+, Sm3+, and Ce3+) can therefore compete with the hole trap defects production as represented for Eu-, Sm-, and Ce-doped ABS glasses. Relative proportion between hole and electron defects in the EPR spectra of irradiated RE-doped ABS glasses can be considered as a parameter for the estimation of the interaction of doping ions with the ionizing radiation.

However, other parameters can influence the nature of the different defects produced during irradiation and more specifically the speciation of the RE ions inside the host glasses. Indeed, some authors like Li and coworkers have studied the solubility and the environment of gadolinium in borosilicate glass compositions [34, 35]. They show that this RE ion is preferentially located in the vicinity of boron network former. According to literature, this RE ion is not therefore homogeneously distributed inside glass. This result influence strongly the EPR spectra of irradiated

**141**

*Influence of the Doping Ion Nature and Content on Defect Creation Processes under the Effect…*

Gd-doped ABS glasses (**Figure 1**) where the defect EPR spectrum is broad and not resolved due to dipole-dipole interaction between BOHC centers and paramagnetic Gd3+ ions. This effect could also explain the evolution of the EPR spectra of Eu-doped ABS glasses (**Figures 5a** and **5b**) as a function of doping ion content. This figure shows both decrease of the relative proportion of BOHC and E′ centers contributions in the defect EPR spectra. As Eu ions can be considered as an electron trap, the changes in relative proportion between OXY and BOHC defects shown in **Figure 6a** could show Eu speciation in the vicinity of boron network former. In order to understand the RE doping influence on defect production under ionizing radiation, Magic Angle Spinning Nuclear magnetic resonance spectroscopy (MAS NMR) of 11B could be a way for studying as a function of RE nature in glasses, their

The second influence of RE doping inside ABS glasses concerns the efficiency of defect production as a function of both nature of the doping ions and its content (**Figure 3**). The decrease of paramagnetic defects concentration can be due to the fact that the electron-hole pairs produced during ionizing radiation can support dynamical balance between the two different charge states of RE ions

+ (h°/e<sup>−</sup>) = > REn + 1 + e<sup>−</sup> = > RE<sup>n</sup>

Gy. Structural changes were observed for irradiated

Gy due to the effect of ionizing radiation and

).

Gy)

+ h° = > REn + 1 or REn

Therefore, this process efficiency of defect production can be correlated to the stability of different oxidation states for different RE ions. Moreover, it is known that increase of the dopant content up to 1 mol.% in highly irradiated (3 × 109

Fe3+- and Cr3+-doped glasses may lead to the complete disappearance of the defect EPR spectrum [29, 30]. But it is necessary to take into consideration the Fe3+ (Cr3+) ions dipole-dipole interaction effect on the defect EPR spectrum. In that case, the disappearance or decrease of defect EPR spectrum in the doped glasses as a function of doping ion content could also be associated with heterogeneous speciation of defects produced during exposure to ionizing radiation in the vicinity of dop-

For all RE doping ABS glasses considered in this work, saturation behavior of defect EPR spectra is analyzed as the function of the integrated dose. This result is explained by the strong efficiency of the dynamical trapping processes of electronhole pairs on different redox states of RE doping ions with respect to the defect production efficiency under the effect of ionizing radiation in this ABS glass. In addition in **Figure 2a** and **b**, the defect content is decreasing in some cases at inte-

might be correlated to the alkaline migration [31]. The decrease of defect content at higher doses could therefore show an important role of precursor defect on the

The available structural information on defects in glass was derived mainly from the results of electron paramagnetic resonance (EPR) spectrometry. It should be noticed that this method is directly applicable only to the subclass of defects which are paramagnetic. A more formidable problem is the pre-existing intrinsic point defects, which are not of paramagnetic nature. Examples of intrinsic diamagnetic defects believed to occur in silica glass include neutral oxygen vacancies (≡Si-Si≡), two-coordinated silicone (O–Si–O–), and peroxy linkages (≡Si–O–O–Si≡) [5]. The most common extrinsic defects are associated with hydroxyl and chloride impurities [16]. It is obvious that the defect designation in multicomponent glasses is extremely complex. Thus, the combined information obtained from EPR- and

alkaline migration processes leading to glass structural changes.

**5. Optical spectra: Effect of RE doping on defect band**

*DOI: http://dx.doi.org/10.5772/intechopen.92317*

possible influence on BOHC defect production.

(REn + 1 + (h°/e<sup>−</sup>) = > RE<sup>n</sup>

grated doses higher than 5 × 108

glass samples at doses around 109

ing ions.

*Influence of the Doping Ion Nature and Content on Defect Creation Processes under the Effect… DOI: http://dx.doi.org/10.5772/intechopen.92317*

Gd-doped ABS glasses (**Figure 1**) where the defect EPR spectrum is broad and not resolved due to dipole-dipole interaction between BOHC centers and paramagnetic Gd3+ ions. This effect could also explain the evolution of the EPR spectra of Eu-doped ABS glasses (**Figures 5a** and **5b**) as a function of doping ion content. This figure shows both decrease of the relative proportion of BOHC and E′ centers contributions in the defect EPR spectra. As Eu ions can be considered as an electron trap, the changes in relative proportion between OXY and BOHC defects shown in **Figure 6a** could show Eu speciation in the vicinity of boron network former. In order to understand the RE doping influence on defect production under ionizing radiation, Magic Angle Spinning Nuclear magnetic resonance spectroscopy (MAS NMR) of 11B could be a way for studying as a function of RE nature in glasses, their possible influence on BOHC defect production.

The second influence of RE doping inside ABS glasses concerns the efficiency of defect production as a function of both nature of the doping ions and its content (**Figure 3**). The decrease of paramagnetic defects concentration can be due to the fact that the electron-hole pairs produced during ionizing radiation can support dynamical balance between the two different charge states of RE ions (REn + 1 + (h°/e<sup>−</sup>) = > RE<sup>n</sup> + h° = > REn + 1 or REn + (h°/e<sup>−</sup>) = > REn + 1 + e<sup>−</sup> = > RE<sup>n</sup> ). Therefore, this process efficiency of defect production can be correlated to the stability of different oxidation states for different RE ions. Moreover, it is known that increase of the dopant content up to 1 mol.% in highly irradiated (3 × 109 Gy) Fe3+- and Cr3+-doped glasses may lead to the complete disappearance of the defect EPR spectrum [29, 30]. But it is necessary to take into consideration the Fe3+ (Cr3+) ions dipole-dipole interaction effect on the defect EPR spectrum. In that case, the disappearance or decrease of defect EPR spectrum in the doped glasses as a function of doping ion content could also be associated with heterogeneous speciation of defects produced during exposure to ionizing radiation in the vicinity of doping ions.

For all RE doping ABS glasses considered in this work, saturation behavior of defect EPR spectra is analyzed as the function of the integrated dose. This result is explained by the strong efficiency of the dynamical trapping processes of electronhole pairs on different redox states of RE doping ions with respect to the defect production efficiency under the effect of ionizing radiation in this ABS glass. In addition in **Figure 2a** and **b**, the defect content is decreasing in some cases at integrated doses higher than 5 × 108 Gy. Structural changes were observed for irradiated glass samples at doses around 109 Gy due to the effect of ionizing radiation and might be correlated to the alkaline migration [31]. The decrease of defect content at higher doses could therefore show an important role of precursor defect on the alkaline migration processes leading to glass structural changes.

#### **5. Optical spectra: Effect of RE doping on defect band**

The available structural information on defects in glass was derived mainly from the results of electron paramagnetic resonance (EPR) spectrometry. It should be noticed that this method is directly applicable only to the subclass of defects which are paramagnetic. A more formidable problem is the pre-existing intrinsic point defects, which are not of paramagnetic nature. Examples of intrinsic diamagnetic defects believed to occur in silica glass include neutral oxygen vacancies (≡Si-Si≡), two-coordinated silicone (O–Si–O–), and peroxy linkages (≡Si–O–O–Si≡) [5]. The most common extrinsic defects are associated with hydroxyl and chloride impurities [16]. It is obvious that the defect designation in multicomponent glasses is extremely complex. Thus, the combined information obtained from EPR- and

*Recent Techniques and Applications in Ionizing Radiation Research*

defect production efficiencies and the changes in the relative proportions of defects composing the EPR spectra of these irradiated glass samples. However, a decrease in the relative proportion of the different defect holes centers (BOHC, Oxy, HC1) for

 *Gy (the EPR spectra have been normalized to BOHC EPR line intensity).*

*X band EPR spectra recorded at room temperature of 0.1, 0.2, 0.6, and 1 mol.% Nd2O3-doped ABS glass* 

This effect could also be correlated to the evolution analyzed for Ce-doped ABS glasses. The changes of the relative proportions of defect as a function of Sm-doping content in ABS glasses (**Figure 6**) show mainly the decrease of E′ defect component in the EPR spectra. Associated to this decrease, an increase in the relative proportion of OXY center relative to relative to BOHC defect is also detected. The experiments testify that glass doping processes can influence the proportion between different defects produced during irradiation compared to the non-doped glass composition. This change has been usually correlated to the capacity of the doping ion to act as a trap for the holes and electrons produced during irradiation. Eu3+ ions are known to be good electron traps and one can observe on **Figures 1** and **5a** the strong decrease of the E′ proportion relatively to the non-doped ABS glasses. Sm3+ ion can also be reduced during the exposure to ionizing radiation but with a weaker efficiency than Eu3+ ions, this effect is also observed on the decrease of the relative proportion of E′ centers in the defect EPR spectra (**Figures 1** and **6**). By contrast, Ce3+ ions produced during irradiation or during the synthesis of Ce-doped glasses is a well-known hole traps [32, 33]. So these ions (Eu3+, Sm3+, and Ce3+) can therefore compete with the hole trap defects production as represented for Eu-, Sm-, and Ce-doped ABS glasses. Relative proportion between hole and electron defects in the EPR spectra of irradiated RE-doped ABS glasses can be considered as a parameter for the estimation of the interaction of doping ions with the ionizing radiation. However, other parameters can influence the nature of the different defects produced during irradiation and more specifically the speciation of the RE ions inside the host glasses. Indeed, some authors like Li and coworkers have studied the solubility and the environment of gadolinium in borosilicate glass compositions [34, 35]. They show that this RE ion is preferentially located in the vicinity of boron network former. According to literature, this RE ion is not therefore homogeneously distributed inside glass. This result influence strongly the EPR spectra of irradiated

the different Nd-doped ABS glasses (**Figure 7**) can be observed.

**140**

**Figure 7.**

*irradiated at 1.3 × 108*

optical (absorption and photoluminescence (PL)) spectra can give an additional data on the structure of the glasses and of the pre-existing/radiation-induced imperfections. Often some defects can provide large EPR signal but the induced optical extinction (transmission loss) is very low and vice versa.

A compendium of EPR/optical correlations was reported in the literature [36, 37] and pointed to the most likely origins of many defect-related optical absorption bands in the visible, ultraviolet, and vacuum-ultraviolet spectral regions. But the assignment of the bands is still controversial in some cases. In this section, some preliminary results on optical study of pristine and irradiated ABS glass doped with RE ions are presented.

Non-doped ABS glass has high ultraviolet transmission. No significant defect generation was detected (**Figures 8** and **9**, black line) in pristine glass. Only small transmission losses in the UV spectral region 230–240 nm were found (**Figure 9**) to be, it seems, connected with oxygen-deficient centers formed on the basis of silicon [15]. Oxygen-deficient centers (ODC, "oxygen vacancies") are the natural type of intrinsic defects in non-stoichiometric silicon dioxide [38]. By the existence of these types of defect in silica optical and luminescent properties are defined as described in [38, 39]. The dominating opinion has been still to consider vacancies of bridging oxygen atoms as the precursors of radiation E′ centers [38, 39]. Thus, ODCs play the key role in E′ center formation and their concentrations in glass. In irradiated ABS glass (BK7 or Duran type) the silicon and boron related electron centers (SiEC and BEC are considered to be responsible for this absorption) [37]. Also after irradiation with high dose (more than 109 Gy) some additional transmission losses can be observed in visible part of the spectra at ~360 and 600 nm (**Figures 9** and **10**, red line) caused by intrinsic radiation defect generation. In [37], these bands are attributed to the BOHC defects in ABS glass.

Photoluminescence (PL) was detected in both pristine and irradiated ABS glasses. As aforementioned in the spectra of pristine ABS glass the ODCs are displayed in the form of an absorption band at 230–240 nm. According to [15] ODSs emission is observed at 280 and 450 nm. Under excitation of forth harmonic

**143**

**Figure 9.**

**Figure 10.**

*Absorption spectra of pristine and irradiated (109*

*Influence of the Doping Ion Nature and Content on Defect Creation Processes under the Effect…*

of Nd:YAG laser (266 nm) we can see only the appearance of broad PL band at ~500 nm for both pristine (**Figure 8**, black line) and β-irradiated glass samples (**Figure 8**, red line). It should be noticed that the position, shape, width, and intensity of this band are different for these two glass samples (**Figure 8**). Time-resolved luminescence measurements carried out with laser excitation (266 nm) revealed the variety of pre-existing point defects in ABS glass (**Figure 10a**) most of them are not identified and described in the literature on our opinion. For one exception: the band at 442 nm can be attributed to ODC which is consistent with data [15]. Especially taking into account that β-irradiation terminates this emission completely as well as two others at 336 and 510 nm. At the same time the new one (540 nm (5.3 eV); perhaps attributed to NBOHC [36]) is arising

*Time-resolved luminescence spectra of pristine: (a) and irradiated (109*

*measured at different gate width and time delay (λexc = 266 nm Nd:YAG laser).*

 *Gy) non-doped ABS glasses.*

 *Gy); (b) non-doped ABS glasses* 

*DOI: http://dx.doi.org/10.5772/intechopen.92317*

**Figure 8.** *Transmission and PL spectra of pristine and irradiated (109 Gy) non-doped ABS glasses.*

*Influence of the Doping Ion Nature and Content on Defect Creation Processes under the Effect… DOI: http://dx.doi.org/10.5772/intechopen.92317*

**Figure 9.**

*Recent Techniques and Applications in Ionizing Radiation Research*

ABS glass doped with RE ions are presented.

tion with high dose (more than 109

attributed to the BOHC defects in ABS glass.

*Transmission and PL spectra of pristine and irradiated (109*

optical extinction (transmission loss) is very low and vice versa.

optical (absorption and photoluminescence (PL)) spectra can give an additional data on the structure of the glasses and of the pre-existing/radiation-induced imperfections. Often some defects can provide large EPR signal but the induced

A compendium of EPR/optical correlations was reported in the literature [36, 37] and pointed to the most likely origins of many defect-related optical absorption bands in the visible, ultraviolet, and vacuum-ultraviolet spectral regions. But the assignment of the bands is still controversial in some cases. In this section, some preliminary results on optical study of pristine and irradiated

Non-doped ABS glass has high ultraviolet transmission. No significant defect generation was detected (**Figures 8** and **9**, black line) in pristine glass. Only small transmission losses in the UV spectral region 230–240 nm were found (**Figure 9**) to be, it seems, connected with oxygen-deficient centers formed on the basis of silicon [15]. Oxygen-deficient centers (ODC, "oxygen vacancies") are the natural type of intrinsic defects in non-stoichiometric silicon dioxide [38]. By the existence of these types of defect in silica optical and luminescent properties are defined as described in [38, 39]. The dominating opinion has been still to consider vacancies of bridging oxygen atoms as the precursors of radiation E′ centers [38, 39]. Thus, ODCs play the key role in E′ center formation and their concentrations in glass. In irradiated ABS glass (BK7 or Duran type) the silicon and boron related electron centers (SiEC and BEC are considered to be responsible for this absorption) [37]. Also after irradia-

be observed in visible part of the spectra at ~360 and 600 nm (**Figures 9** and **10**, red line) caused by intrinsic radiation defect generation. In [37], these bands are

Photoluminescence (PL) was detected in both pristine and irradiated ABS glasses. As aforementioned in the spectra of pristine ABS glass the ODCs are displayed in the form of an absorption band at 230–240 nm. According to [15] ODSs emission is observed at 280 and 450 nm. Under excitation of forth harmonic

Gy) some additional transmission losses can

 *Gy) non-doped ABS glasses.*

**142**

**Figure 8.**

*Absorption spectra of pristine and irradiated (109 Gy) non-doped ABS glasses.*

#### **Figure 10.**

*Time-resolved luminescence spectra of pristine: (a) and irradiated (109 Gy); (b) non-doped ABS glasses measured at different gate width and time delay (λexc = 266 nm Nd:YAG laser).*

of Nd:YAG laser (266 nm) we can see only the appearance of broad PL band at ~500 nm for both pristine (**Figure 8**, black line) and β-irradiated glass samples (**Figure 8**, red line). It should be noticed that the position, shape, width, and intensity of this band are different for these two glass samples (**Figure 8**).

Time-resolved luminescence measurements carried out with laser excitation (266 nm) revealed the variety of pre-existing point defects in ABS glass (**Figure 10a**) most of them are not identified and described in the literature on our opinion. For one exception: the band at 442 nm can be attributed to ODC which is consistent with data [15]. Especially taking into account that β-irradiation terminates this emission completely as well as two others at 336 and 510 nm. At the same time the new one (540 nm (5.3 eV); perhaps attributed to NBOHC [36]) is arising

but emission band at 490 nm is still observed with higher intensity in irradiated ABS glass (**Figure 10b**). It should be marked here that the band at 336 nm can be also assigned to the ODCs since as it is indicated in [15] "Si ODCs in the silica glass network are an ensemble of defects such as 'oxygen vacancies', which differ in local structural environment, i.e., in the symmetry and strength of the local crystalline fields around the ODC." That is why the ODCs to be characterized by a rather wide variety of spectral characteristics.

The incorporation of RE ions into the ABS glass matrix affects its optical properties. The evolution of optical characteristics is discussed in frame of the non-bridging oxygen formation in the glass structure, as well as color centers as a function of the nature of the RE element. By increasing the number of Nd (Gd) ions in ABS glass, it is possible to observe a decrease in the number of non-bridging oxygen per silicon tetrahedron in the glass studied which is confirmed by the estimate of the optical band gap and the Raman spectroscopy data. The presence of two charge states of multivalent Eu and Ce ions having absorption in the UV region complicates the consideration of the effect of the processes on the observed change in the optical band gap energy. The effect of irradiation results in color centers content increase (observed as more intense brown coloration of the irradiated glass) in the following sequence, Nd < Gd < Sm = Eu < Ce. This evolution is reflected on the optical band gap narrowing [40]. **Figure 11** presents transmission and PL spectra of the highly Sm-doped (1 mol.%) pristine and irradiated ABS glass. Some transmission losses can be observed for pristine glass from **Figure 12**: firstly, due to the presence of Sm3+ ions in glass structure (sharp lines in the spectra) and secondly, due to the presence of ODCs (similar to the non-doped ABS glass, see **Figure 8**). The emission spectra consist of the well-known bands belonging to the Sm3+/Sm2+ ions and the broad band around 500 nm, attributed to the ODCs: intensity of this band decreases significantly by β-irradiation (**Figure 11**).

The transmission spectra of Gd-doped ABS glass do not change significantly in comparison with non-doped glass except the fact that no prominent transmission losses are observed at 360 and 600 nm in irradiated glass (**Figure 12**). Emission of ODCs are located in the visible part of PL spectra at ~500 nm as it was seen before

**145**

**Figure 13.**

**Figure 12.**

*Influence of the Doping Ion Nature and Content on Defect Creation Processes under the Effect…*

for non-doped and Sm-doped ABS glass (**Figures 8** and **11**, respectively). It was shown [41] that this emission can also be excited by third harmonic of Nd:YAG laser (355 nm). Unfortunately, no information about ODCs optical characteristics could

 *Gy) Gd-doped ABS glasses.*

tion in the UV studied spectral region [40]. It is clearly seen that the absorption and PL characteristics of ODCs in non-doped ABS glass, as well as in glass doped with Sm or Gd ions, are analogous to each other with the exception of unresolved PL

4+ absorp-

be obtained in Eu- or Ce-doped ABS glasses because of strong Eu2+, Ce3+/

bands structure in case of doping (**Figure 13**).

*Evolution of the defect emission band on RE dopant nature.*

*Transmission and PL spectra of pristine and irradiated (109*

*DOI: http://dx.doi.org/10.5772/intechopen.92317*

**Figure 11.** *Transmission and PL spectra of pristine and irradiated (109 Gy) Sm-doped ABS glasses.*

*Influence of the Doping Ion Nature and Content on Defect Creation Processes under the Effect… DOI: http://dx.doi.org/10.5772/intechopen.92317*

**Figure 12.** *Transmission and PL spectra of pristine and irradiated (109 Gy) Gd-doped ABS glasses.*

for non-doped and Sm-doped ABS glass (**Figures 8** and **11**, respectively). It was shown [41] that this emission can also be excited by third harmonic of Nd:YAG laser (355 nm). Unfortunately, no information about ODCs optical characteristics could be obtained in Eu- or Ce-doped ABS glasses because of strong Eu2+, Ce3+/ 4+ absorption in the UV studied spectral region [40]. It is clearly seen that the absorption and PL characteristics of ODCs in non-doped ABS glass, as well as in glass doped with Sm or Gd ions, are analogous to each other with the exception of unresolved PL bands structure in case of doping (**Figure 13**).

**Figure 13.** *Evolution of the defect emission band on RE dopant nature.*

*Recent Techniques and Applications in Ionizing Radiation Research*

decreases significantly by β-irradiation (**Figure 11**).

*Transmission and PL spectra of pristine and irradiated (109*

variety of spectral characteristics.

but emission band at 490 nm is still observed with higher intensity in irradiated ABS glass (**Figure 10b**). It should be marked here that the band at 336 nm can be also assigned to the ODCs since as it is indicated in [15] "Si ODCs in the silica glass network are an ensemble of defects such as 'oxygen vacancies', which differ in local structural environment, i.e., in the symmetry and strength of the local crystalline fields around the ODC." That is why the ODCs to be characterized by a rather wide

The incorporation of RE ions into the ABS glass matrix affects its optical properties. The evolution of optical characteristics is discussed in frame of the non-bridging oxygen formation in the glass structure, as well as color centers as a function of the nature of the RE element. By increasing the number of Nd (Gd) ions in ABS glass, it is possible to observe a decrease in the number of non-bridging oxygen per silicon tetrahedron in the glass studied which is confirmed by the estimate of the optical band gap and the Raman spectroscopy data. The presence of two charge states of multivalent Eu and Ce ions having absorption in the UV region complicates the consideration of the effect of the processes on the observed change in the optical band gap energy. The effect of irradiation results in color centers content increase (observed as more intense brown coloration of the irradiated glass) in the following sequence, Nd < Gd < Sm = Eu < Ce. This evolution is reflected on the optical band gap narrowing [40]. **Figure 11** presents transmission and PL spectra of the highly Sm-doped (1 mol.%) pristine and irradiated ABS glass. Some transmission losses can be observed for pristine glass from **Figure 12**: firstly, due to the presence of Sm3+ ions in glass structure (sharp lines in the spectra) and secondly, due to the presence of ODCs (similar to the non-doped ABS glass, see **Figure 8**). The emission spectra consist of the well-known bands belonging to the Sm3+/Sm2+ ions and the broad band around 500 nm, attributed to the ODCs: intensity of this band

The transmission spectra of Gd-doped ABS glass do not change significantly in comparison with non-doped glass except the fact that no prominent transmission losses are observed at 360 and 600 nm in irradiated glass (**Figure 12**). Emission of ODCs are located in the visible part of PL spectra at ~500 nm as it was seen before

 *Gy) Sm-doped ABS glasses.*

**144**

**Figure 11.**

It was natural to suppose that we have similar types of defect. But for the moment it is not absolutely clear whether these ODCs have essentially different structure or whether they are the same vacancies with distorted environment. Moreover, the modified shape of the PL band can be consistent with the assumption about the effect of segregation of defects and impurities that can influence the variations of the spectral characteristics of the ODCs. In the previous section, the relative increase in the proportion of peroxy radicals (Si–O–O°: Oxy defects) with the Eu concentration as well of the Oxy and the HC1 (Si–O Na<sup>+</sup> ) centers with Ce concentration (**Figures 4** and **5**) was reported. Probably it means that the structural model of the OXY and HC1 centers tightly depends on the structural model of the ODC and it is still open for discussion. As to our point of view observed experimental facts can be most naturally explained by segregation of impurities and defects in the glass network. The effect of selective incorporation of a RE dopant into the glass due to the heterogeneous glass structure, leading to a RE concentration dependent dopant displacement as well as concentration dependent optical and physical-chemical glass properties which was firstly mentioned in the 1970 [42]. Then phase-separation model was suggested in order to explain structural evolution of RE-doped borosilicate glass [34, 35].

Analysis of the results presented allowed to draw a conclusion that due to RE speciation in the ABS glass structure and heterogeneous distribution between different environments RE doping affects strongly defect production (firstly, preexisting defects). Additional studies on RE concentration dependent time-resolved luminescence ABS glass might be required.

#### **6. Summary and outlook**

The presented study has shown significant changes in defect creation processes under ionizing radiation in ABS glasses as a function of the nature and the content of different rare earth-doping ions (RE = Sm, Gd, Eu, Ce, and Nd). We observe first that doping processes influence significantly the nature of the different defect produced during ionizing radiation and more specifically the ratio between hole and electron defect centers observed by EPR spectroscopy. The specific role of RE doping ion acting as a hole or an electron trap could control the population of different defects produced during irradiation. The second result of doping is a strong decrease in defect production efficiency under the effect of ionizing radiation depending on both the RE doping content in the glass and on the relative stability of the RE different oxidation states. This result could be explained by dynamical reversible trapping of the electron-hole pairs produced during irradiation on the RE ions as well as by RE segregation and pre-existing defects speciation in ABS glass structure.

In order to understand the RE doping influence on defect production under the effect of ionizing radiation, Magic Angle Spinning Nuclear magnetic resonance spectroscopy (MAS NMR) of 11B could be a way for studying as a function of RE nature in glasses and their possible influence on BOHC defect production.

#### **Acknowledgements**

I would like to thank Thierry Pouthier and Vincent Métayer for their contribution during external β-irradiation experiments. I do appreciate also to Dr. B. Boizot for stimulating my interest in this field and for pointing to my attention several interesting experimental problems as well as for many enlightening discussions.

**147**

**Author details**

Eugenia Malchukova

Ioffe Institute, Russian Academy of Sciences, St. Petersburg, Russia

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

\*Address all correspondence to: e.malchukova@mail.ioffe.ru

provided the original work is properly cited.

*Influence of the Doping Ion Nature and Content on Defect Creation Processes under the Effect…*

*DOI: http://dx.doi.org/10.5772/intechopen.92317*

*Influence of the Doping Ion Nature and Content on Defect Creation Processes under the Effect… DOI: http://dx.doi.org/10.5772/intechopen.92317*

#### **Author details**

*Recent Techniques and Applications in Ionizing Radiation Research*

the Eu concentration as well of the Oxy and the HC1 (Si–O Na<sup>+</sup>

of RE-doped borosilicate glass [34, 35].

luminescence ABS glass might be required.

**6. Summary and outlook**

It was natural to suppose that we have similar types of defect. But for the moment it is not absolutely clear whether these ODCs have essentially different structure or whether they are the same vacancies with distorted environment. Moreover, the modified shape of the PL band can be consistent with the assumption about the effect of segregation of defects and impurities that can influence the variations of the spectral characteristics of the ODCs. In the previous section, the relative increase in the proportion of peroxy radicals (Si–O–O°: Oxy defects) with

concentration (**Figures 4** and **5**) was reported. Probably it means that the structural model of the OXY and HC1 centers tightly depends on the structural model of the ODC and it is still open for discussion. As to our point of view observed experimental facts can be most naturally explained by segregation of impurities and defects in the glass network. The effect of selective incorporation of a RE dopant into the glass due to the heterogeneous glass structure, leading to a RE concentration dependent dopant displacement as well as concentration dependent optical and physical-chemical glass properties which was firstly mentioned in the 1970 [42]. Then phase-separation model was suggested in order to explain structural evolution

Analysis of the results presented allowed to draw a conclusion that due to RE speciation in the ABS glass structure and heterogeneous distribution between different environments RE doping affects strongly defect production (firstly, preexisting defects). Additional studies on RE concentration dependent time-resolved

The presented study has shown significant changes in defect creation processes under ionizing radiation in ABS glasses as a function of the nature and the content of different rare earth-doping ions (RE = Sm, Gd, Eu, Ce, and Nd). We observe first that doping processes influence significantly the nature of the different defect produced during ionizing radiation and more specifically the ratio between hole and electron defect centers observed by EPR spectroscopy. The specific role of RE doping ion acting as a hole or an electron trap could control the population of different defects produced during irradiation. The second result of doping is a strong decrease in defect production efficiency under the effect of ionizing radiation depending on both the RE doping content in the glass and on the relative stability of the RE different oxidation states. This result could be explained by dynamical reversible trapping of the electron-hole pairs produced during irradiation on the RE ions as well as by RE segregation and pre-existing defects speciation in ABS glass

In order to understand the RE doping influence on defect production under the effect of ionizing radiation, Magic Angle Spinning Nuclear magnetic resonance spectroscopy (MAS NMR) of 11B could be a way for studying as a function of RE nature in glasses and their possible influence on BOHC defect production.

I would like to thank Thierry Pouthier and Vincent Métayer for their contribution during external β-irradiation experiments. I do appreciate also to Dr. B. Boizot for stimulating my interest in this field and for pointing to my attention several interesting experimental problems as well as for many enlightening discussions.

) centers with Ce

**146**

structure.

**Acknowledgements**

Eugenia Malchukova Ioffe Institute, Russian Academy of Sciences, St. Petersburg, Russia

\*Address all correspondence to: e.malchukova@mail.ioffe.ru

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

### **References**

[1] Pacchioni G, Skuja L, Griscom DL, editors. Defects in SiO2 and Related Dielectrics: Science and Technology. Dordrecht: Kluwer Academic Publishers; 2000. DOI: 10.1007/978-94- 010-0944-7. 615p

[2] Grillanda S, Singh V, Raghunathan V, Morichetti F, Melloni A, Kimerling L, et al. Gamma radiation effects on silicon photonic waveguides. Optics Letters. 2016;**41**(13):3053-3056. DOI: 10.1364/ OL.41.003053

[3] Lisovskyy IP, Voitovych MV, Voitovych VV, Khacevich IM. Influence of radiation on the luminescence of silicon nanocrystals embedded into SiO2 film. Journal of Nanomaterials. 2016;**2016**:9674741. DOI: 10.1155/2016/9674741

[4] Alessia A, Richard N, Martin-Samos L, De Michelea V, Giacomazzi L, Agnello S, et al. Overview of radiation induced point defects in silica-based optical fibers. Physical Review. 2019;**4**:100032(18). DOI: 10.1016/j.revip.2019.100032

[5] Griscom DL. Optical properties and structure of defects in silica glass. Journal of the Ceramic Society of Japan. 1991;**99**:923-942

[6] Du Q, Huang Y, Ogbuu O, Zhang W, Li J, Singh V, et al. Gamma radiation effects in amorphous silicon and silicon nitride photonic devices. Optics Letters. 2017;**42**(3):587-590. DOI: 10.1364/ OL.42.000

[7] Skuja L, Hirano M, Hosono H, Kajihara K. Defects in oxide glasses. Physica Status Solidi C. 2005;**2**(1):15-24. DOI: 10.1002/pssc.200460102

[8] Imai H, Hirashima H. Intrinsic- and extrinsic-defect formation in silica glasses by radiation. Journal of Non-Crystalline Solids. 1994;**179**:202-213. DOI: 10.1016/0022-3093(94)90698-X

[9] Devine RAB, Arndt J. Correlated defect creation and dose-dependent radiation sensitivity in amorphous SiO2. Physical Review B. 1989;**39**(8):5132- 5138. DOI: 10.1103/physrevb.39.5132

[10] Devine RAB, Arndt J. Defect pair creation through ultraviolet radiation in dense, amorphous SiO2. Physical Review B. 1990;**42**(4):2617-2620. DOI: 10.1103/physrevb.42.2617

[11] Weeks RA. The many varieties of E' centers: A review. Journal of Non-Crystalline Solids. 1994;**179**:1-9. DOI: 10.1016/0022-3093(94)90680-7

[12] Griscom DL, Friebele EJ. Fundamental defect centers in glass: 29Si hyperfine structure of the nonbridging oxygen hole center and the peroxy radical in a-SiO2. Physical Review B. 1981;**2**(8):4896-4898. DOI: 10.1103/PhysRevB.24.4896

[13] Imai H, Arai K, Isoya J, Hosono H, Abe Y, Imagawa H. Generation of E' centers and oxygen hole centers in synthetic silica glasses by gamma irradiation. Physical Review B. 1993;**48**(2):3116-3123. DOI: 10.1103/ physrevb.48.3116

[14] Zhang L, Mashkov VA, Leisure RG. Multiple interconversions of the E' and oxygen-hole defect centers in highpurity amorphous silica during annealinterrupted x irradiation. Physical Review Letters. 1995;**74**(9):1605-1608. DOI: 10.1103/PhysRevLett.74.1605

[15] Amossov AV, Rybaltovsky AO. Radiation color center formation in silica glasses: A review of photo- and thermo-chemical aspects of the problem. Journal of Non-Crystalline Solids. 1994;**179**:226-234. DOI: 10.1016/0022-3093(94)90700-5

[16] Skuja L, Kajihara K, Hirano M, Hosono H. Hydrogen-related radiation

**149**

*Influence of the Doping Ion Nature and Content on Defect Creation Processes under the Effect…*

radiation damage in silicate glasses. Journal of Non-Crystalline Solids. 1982;**50**:79-95. DOI: 10.1016/0022-

[24] Griscom DL. Electron spin resonance studies of trapped hole centers in irradiated alkali silicate glasses: A critical comment on current models for HC1 and HC2. Journal of Non-Crystalline Solids. 1984;**64**:229-247. DOI: 10.1016/0022-3093(84)90220-5

[25] Boizot B, Petite G, Ghaleb D, Calas G. Radiation induced paramagnetic centers in nuclear glasses by EPR spectroscopy. Nuclear Instruments and Methods in Physics Research B. 1998;**141**:580-584. DOI: 10.1016/S0168-583X(98)00102-5

[26] Malchukova E, Boizot B, Petite G, Ghaleb D. Optical properties and valence state of Sm ions in aluminoborosilicate glass under β-irradiation. Journal of Non-Crystalline Solids. 2007;**353**: 2397-2402. DOI: 10.1016/j.jnoncrysol.

[27] Malchukova E, Boizot B, Ghaleb D,

[28] Ollier N, Planchais R, Boizot B. EPR study of Yb-doped irradiated glasses. Nuclear Instruments and Methods in Physics Research B. 2008;**266**(12-13): 2854-2858. DOI: 10.1016/j.nimb.

[29] Olivier FY, Boizot B, Ghaleb D, Petite G. Raman and EPR studies of β-irradiated oxide glasses: The effect of Iron concentration. Journal of Non-

Crystalline Solids. 2005;**351** (12-13):1061-1066. DOI: 10.1016/j.

jnoncrysol.2005.01.018

Petite G. β-Irradiation effects in Gd-doped borosilicate glasses studied by EPR and Raman spectroscopies. Journal of Non-Crystalline Solids. 2006;**352**(4):297-303. DOI: 10.1016/j.

jnoncrysol.2005.11.003

2007.04.003

2008.03.129

3093(82)90202-2

*DOI: http://dx.doi.org/10.5772/intechopen.92317*

defects in SiO2-based glasses. Nuclear Instruments and Methods in Physics Research B. 2008;**266**(12-13):2971-2975.

DOI: 10.1016/j.nimb.2008.03.150

[17] Elsts E, Rogulis U, Bulindzs K, Smits K, Zolotarjovs A, Trinkler L, et al. Studies of radiation defects in cerium, europium and terbium activated oxyfluoride glasses and glass ceramics. Optical Materials. 2015;**41**:90-93. DOI:

10.1016/j.optmat.2014.10.042

[18] Uklein AV, Popov AS, Lisnyak VV, Zaderko AN, Linnik RP, Boldyrieva OY, et al. Probing of the oxygen-related defects response in Nd:phosphate glass within self-action of the laser radiation technique. Journal of Non-Crystalline Solids. 2018;**498**:244-251. DOI: 10.1016/j.jnoncrysol.2018.06.024

[19] Mashkov VA, Austin WR, Zhang L, Leisure RG. Fundamental role of creation and activation in radiationinduced defect production in highpurity amorphous SiO2. Physical Review Letters. 1996;**76**(6):2926-2929. DOI: 10.1103/PhysRevLett.76.2926

[20] Griscom DL. E.S.R. studies of radiation damage and structure in oxide glasses not containing transition group ions: A contemporary overview with illustrations from the alkali borate system. Journal of Non-Crystalline Solids. 1973;**13**:251-285. DOI: 10.1016/0022-3093(74)90095-7

[21] Kordas G. On the structure of the BOHC in the borosilicate and borophosphosilicate glasses. Journal of Non-Crystalline Solids. 2005;**351**:2348-2360. DOI: 10.1016/j.jnoncrysol.2005.06.010

[22] Dutt DA, Higby PL, Griscom DL. An electron spin resonance study of X-irradiated calcium aluminosilicate glasses. Journal of Non-Crystalline Solids. 1991;**130**:41-521. DOI: 10.1016/

0022-3093(91)90154-X

[23] Kordas G, Camara B, Oel HJ. Electron spin resonance studies of *Influence of the Doping Ion Nature and Content on Defect Creation Processes under the Effect… DOI: http://dx.doi.org/10.5772/intechopen.92317*

defects in SiO2-based glasses. Nuclear Instruments and Methods in Physics Research B. 2008;**266**(12-13):2971-2975. DOI: 10.1016/j.nimb.2008.03.150

[17] Elsts E, Rogulis U, Bulindzs K, Smits K, Zolotarjovs A, Trinkler L, et al. Studies of radiation defects in cerium, europium and terbium activated oxyfluoride glasses and glass ceramics. Optical Materials. 2015;**41**:90-93. DOI: 10.1016/j.optmat.2014.10.042

[18] Uklein AV, Popov AS, Lisnyak VV, Zaderko AN, Linnik RP, Boldyrieva OY, et al. Probing of the oxygen-related defects response in Nd:phosphate glass within self-action of the laser radiation technique. Journal of Non-Crystalline Solids. 2018;**498**:244-251. DOI: 10.1016/j.jnoncrysol.2018.06.024

[19] Mashkov VA, Austin WR, Zhang L, Leisure RG. Fundamental role of creation and activation in radiationinduced defect production in highpurity amorphous SiO2. Physical Review Letters. 1996;**76**(6):2926-2929. DOI: 10.1103/PhysRevLett.76.2926

[20] Griscom DL. E.S.R. studies of radiation damage and structure in oxide glasses not containing transition group ions: A contemporary overview with illustrations from the alkali borate system. Journal of Non-Crystalline Solids. 1973;**13**:251-285. DOI: 10.1016/0022-3093(74)90095-7

[21] Kordas G. On the structure of the BOHC in the borosilicate and borophosphosilicate glasses. Journal of Non-Crystalline Solids. 2005;**351**:2348-2360. DOI: 10.1016/j.jnoncrysol.2005.06.010

[22] Dutt DA, Higby PL, Griscom DL. An electron spin resonance study of X-irradiated calcium aluminosilicate glasses. Journal of Non-Crystalline Solids. 1991;**130**:41-521. DOI: 10.1016/ 0022-3093(91)90154-X

[23] Kordas G, Camara B, Oel HJ. Electron spin resonance studies of radiation damage in silicate glasses. Journal of Non-Crystalline Solids. 1982;**50**:79-95. DOI: 10.1016/0022- 3093(82)90202-2

[24] Griscom DL. Electron spin resonance studies of trapped hole centers in irradiated alkali silicate glasses: A critical comment on current models for HC1 and HC2. Journal of Non-Crystalline Solids. 1984;**64**:229-247. DOI: 10.1016/0022-3093(84)90220-5

[25] Boizot B, Petite G, Ghaleb D, Calas G. Radiation induced paramagnetic centers in nuclear glasses by EPR spectroscopy. Nuclear Instruments and Methods in Physics Research B. 1998;**141**:580-584. DOI: 10.1016/S0168-583X(98)00102-5

[26] Malchukova E, Boizot B, Petite G, Ghaleb D. Optical properties and valence state of Sm ions in aluminoborosilicate glass under β-irradiation. Journal of Non-Crystalline Solids. 2007;**353**: 2397-2402. DOI: 10.1016/j.jnoncrysol. 2007.04.003

[27] Malchukova E, Boizot B, Ghaleb D, Petite G. β-Irradiation effects in Gd-doped borosilicate glasses studied by EPR and Raman spectroscopies. Journal of Non-Crystalline Solids. 2006;**352**(4):297-303. DOI: 10.1016/j. jnoncrysol.2005.11.003

[28] Ollier N, Planchais R, Boizot B. EPR study of Yb-doped irradiated glasses. Nuclear Instruments and Methods in Physics Research B. 2008;**266**(12-13): 2854-2858. DOI: 10.1016/j.nimb. 2008.03.129

[29] Olivier FY, Boizot B, Ghaleb D, Petite G. Raman and EPR studies of β-irradiated oxide glasses: The effect of Iron concentration. Journal of Non-Crystalline Solids. 2005;**351** (12-13):1061-1066. DOI: 10.1016/j. jnoncrysol.2005.01.018

**148**

*Recent Techniques and Applications in Ionizing Radiation Research*

[9] Devine RAB, Arndt J. Correlated defect creation and dose-dependent radiation sensitivity in amorphous SiO2. Physical Review B. 1989;**39**(8):5132- 5138. DOI: 10.1103/physrevb.39.5132

[10] Devine RAB, Arndt J. Defect pair creation through ultraviolet radiation in dense, amorphous SiO2. Physical Review B. 1990;**42**(4):2617-2620. DOI:

[11] Weeks RA. The many varieties of E' centers: A review. Journal of Non-Crystalline Solids. 1994;**179**:1-9. DOI: 10.1016/0022-3093(94)90680-7

Fundamental defect centers in glass: 29Si hyperfine structure of the nonbridging oxygen hole center and the peroxy radical in a-SiO2. Physical Review B. 1981;**2**(8):4896-4898. DOI:

[13] Imai H, Arai K, Isoya J, Hosono H, Abe Y, Imagawa H. Generation of E' centers and oxygen hole centers in synthetic silica glasses by gamma irradiation. Physical Review B. 1993;**48**(2):3116-3123. DOI: 10.1103/

[14] Zhang L, Mashkov VA, Leisure RG. Multiple interconversions of the E' and oxygen-hole defect centers in highpurity amorphous silica during annealinterrupted x irradiation. Physical Review Letters. 1995;**74**(9):1605-1608. DOI: 10.1103/PhysRevLett.74.1605

[15] Amossov AV, Rybaltovsky AO. Radiation color center formation in silica glasses: A review of photo- and thermo-chemical aspects of the problem. Journal of Non-Crystalline Solids. 1994;**179**:226-234. DOI: 10.1016/0022-3093(94)90700-5

[16] Skuja L, Kajihara K, Hirano M, Hosono H. Hydrogen-related radiation

10.1103/physrevb.42.2617

[12] Griscom DL, Friebele EJ.

10.1103/PhysRevB.24.4896

physrevb.48.3116

[1] Pacchioni G, Skuja L, Griscom DL, editors. Defects in SiO2 and Related Dielectrics: Science and Technology. Dordrecht: Kluwer Academic

Publishers; 2000. DOI: 10.1007/978-94-

[2] Grillanda S, Singh V, Raghunathan V, Morichetti F, Melloni A, Kimerling L, et al. Gamma radiation effects on silicon photonic waveguides. Optics Letters. 2016;**41**(13):3053-3056. DOI: 10.1364/

[3] Lisovskyy IP, Voitovych MV,

2016;**2016**:9674741. DOI: 10.1155/2016/9674741

[4] Alessia A, Richard N,

1991;**99**:923-942

OL.42.000

Martin-Samos L, De Michelea V,

[5] Griscom DL. Optical properties and structure of defects in silica glass. Journal of the Ceramic Society of Japan.

[6] Du Q, Huang Y, Ogbuu O, Zhang W, Li J, Singh V, et al. Gamma radiation effects in amorphous silicon and silicon nitride photonic devices. Optics Letters. 2017;**42**(3):587-590. DOI: 10.1364/

[7] Skuja L, Hirano M, Hosono H, Kajihara K. Defects in oxide glasses. Physica Status Solidi C. 2005;**2**(1):15-24.

[8] Imai H, Hirashima H. Intrinsic- and extrinsic-defect formation in silica glasses by radiation. Journal of Non-Crystalline Solids. 1994;**179**:202-213. DOI: 10.1016/0022-3093(94)90698-X

DOI: 10.1002/pssc.200460102

Giacomazzi L, Agnello S, et al. Overview of radiation induced point defects in silica-based optical fibers. Physical Review. 2019;**4**:100032(18). DOI: 10.1016/j.revip.2019.100032

Voitovych VV, Khacevich IM. Influence of radiation on the luminescence of silicon nanocrystals embedded into SiO2 film. Journal of Nanomaterials.

010-0944-7. 615p

**References**

OL.41.003053

[30] Boizot B, Olivier FY, Petite G, Ghaleb D. Blocking of alkaline migration under ionizing irradiation in Cr-doped oxide glasses. Nuclear Instruments and Methods in Physics Research B. 2008;**266**(12-13):2966-2970. DOI: 10.1016/j.nimb.2008.03.149

[31] Boizot B, Ollier N, Olivier F, Petite G, Ghaleb D, Malchukova E. Irradiation effects in simplified nuclear waste glasses. Nuclear Instruments and Methods in Physics Research B. 2005;**240**(1-2):146-151. DOI: 10.1016/j. nimb.2005.06.105

[32] Qiu J, Sugimoto N, Iwabuchi Y, Hirao K. Photostimulated luminescence in Ce3+-doped silicate glasses. Journal of Non-Crystalline Solids. 1997;**209**:200-203. DOI: 10.1016/ S0022-3093(96)00644-8

[33] Vedda A, Nikl M, Fasoli M, Mihokova E, Pejchal J, Dusek M, et al. Thermally stimulated tunneling in rareearth-doped oxyorthosilicates. Physical Review B. 2008;**78**:195123(8). DOI: 10.1103/PhysRevB.78.195123

[34] Li L, Li H, Quian M, Strachan DM. Gadolinium solubility in peralkaline borosilicate glasses. Journal of Non-Crystalline Solids. 2001;**283**:237-245. DOI: 10.1016/S0022-3093(01)00480-X

[35] Li H, Su Y, Li L, Strachan DM. Raman spectroscopic study of gadolinium(III) in sodium-aluminoborosilicate glasses. Journal of Non-Crystalline Solids. 2001;**292**:167-176. DOI: 10.1016/ S0022-3093(01)00878-X

[36] Skuja L. Optically active oxygendeficiency-related centers in amorphous silicon dioxide. Journal of Non-Crystalline Solids. 1998;**239**(1-3):16-48. DOI: 10.1016/S0022-3093(98)00720-0

[37] Ehrt D, Ebeling P. Radiation defects in borosilicate glasses. European Journal of Glass Science and Technology. Part A: Glass Technology. 2003;**44**(2):46-49

[38] Weeks RA. Paramagnetic resonance of lattice defects in irradiated quartz. Journal of Applied Physics. 1956;**27**(11): 1376-1381. DOI: 10.1063/1.1722267

[39] Hosono H, Abe Y, Kinser DL, Weeks RA, Muta K, Kawazoe H. Nature and origin of the 5-eV band in SiO2:GeO2 glasses. Physical Review B. 1992;**46**:11445-11451. DOI: 10.1103/ physrevb.46.11445

[40] Malchukova EV, Nepomnyashchikh AI, Boizot B, Terukov EI. Radiation effects and optical properties of aluminoborosilicate glass doped with RE ions. Glass Physics and Chemistry. 2018;**44**(4):356-363. DOI: 10.1134/S1087659618040090

#### [41] Mal'chukova EV,

Nepomnyashchikh AI, Boizot B, Shamirzaev TS, Petite G. Luminescence of aluminoborosilicate glasses doped with Gd3+ ions. Physics of the Solid State. 2010;**52**(9):1919-1924. DOI: 10.1134/S1063783410090222

[42] Dmitryuk AV, Karapetyan GO, Maksimov LV. Activator segregation and its spectroscopic signatures. Zhurnal Prikladnoi Spektroskopii. 1975;**22**(1):153-182

*Recent Techniques and Applications in Ionizing Radiation Research*

[38] Weeks RA. Paramagnetic resonance of lattice defects in irradiated quartz. Journal of Applied Physics. 1956;**27**(11): 1376-1381. DOI: 10.1063/1.1722267

[39] Hosono H, Abe Y, Kinser DL, Weeks RA, Muta K, Kawazoe H. Nature and origin of the 5-eV band in SiO2:GeO2 glasses. Physical Review B. 1992;**46**:11445-11451. DOI: 10.1103/

Nepomnyashchikh AI, Boizot B,

10.1134/S1087659618040090

Nepomnyashchikh AI, Boizot B, Shamirzaev TS, Petite G. Luminescence of aluminoborosilicate glasses doped with Gd3+ ions. Physics of the Solid State. 2010;**52**(9):1919-1924. DOI: 10.1134/S1063783410090222

[42] Dmitryuk AV, Karapetyan GO, Maksimov LV. Activator segregation and its spectroscopic signatures. Zhurnal Prikladnoi Spektroskopii.

Terukov EI. Radiation effects and optical properties of aluminoborosilicate glass doped with RE ions. Glass Physics and Chemistry. 2018;**44**(4):356-363. DOI:

physrevb.46.11445

[40] Malchukova EV,

[41] Mal'chukova EV,

1975;**22**(1):153-182

[30] Boizot B, Olivier FY, Petite G, Ghaleb D. Blocking of alkaline migration

under ionizing irradiation in Cr-doped oxide glasses. Nuclear Instruments and Methods in Physics Research B. 2008;**266**(12-13):2966-2970.

DOI: 10.1016/j.nimb.2008.03.149

[31] Boizot B, Ollier N, Olivier F, Petite G, Ghaleb D, Malchukova E. Irradiation effects in simplified nuclear waste glasses. Nuclear Instruments and Methods in Physics Research B. 2005;**240**(1-2):146-151. DOI: 10.1016/j.

[32] Qiu J, Sugimoto N, Iwabuchi Y, Hirao K. Photostimulated luminescence

in Ce3+-doped silicate glasses. Journal of Non-Crystalline Solids. 1997;**209**:200-203. DOI: 10.1016/

[33] Vedda A, Nikl M, Fasoli M, Mihokova E, Pejchal J, Dusek M, et al. Thermally stimulated tunneling in rareearth-doped oxyorthosilicates. Physical Review B. 2008;**78**:195123(8). DOI: 10.1103/PhysRevB.78.195123

[34] Li L, Li H, Quian M, Strachan DM. Gadolinium solubility in peralkaline borosilicate glasses. Journal of Non-Crystalline Solids. 2001;**283**:237-245. DOI: 10.1016/S0022-3093(01)00480-X

[35] Li H, Su Y, Li L, Strachan DM. Raman spectroscopic study of gadolinium(III) in sodium-aluminoborosilicate glasses. Journal of Non-Crystalline Solids. 2001;**292**:167-176. DOI: 10.1016/ S0022-3093(01)00878-X

[36] Skuja L. Optically active oxygendeficiency-related centers in amorphous

Crystalline Solids. 1998;**239**(1-3):16-48. DOI: 10.1016/S0022-3093(98)00720-0

[37] Ehrt D, Ebeling P. Radiation defects in borosilicate glasses. European Journal of Glass Science and Technology. Part A: Glass Technology. 2003;**44**(2):46-49

silicon dioxide. Journal of Non-

S0022-3093(96)00644-8

nimb.2005.06.105

**150**

### *Edited by Ahmed M. Maghraby and Basim Almayyahi*

Ionizing radiation can be found everywhere; in the Earth, inside buildings, in space, in the food we eat, and even inside our bodies. It is of much importance to know more about radiation and how it can improve human life, including how to make use of it and how to avoid its harm. This book covers several topics on ionizing radiation to enrich our knowledge about its applications and effects.

Published in London, UK © 2021 IntechOpen © sakkmesterke / iStock

Recent Techniques and Applications in Ionizing Radiation Research

Recent Techniques and

Applications in Ionizing

Radiation Research

*Edited by Ahmed M. Maghraby and Basim Almayyahi*