**2.3 Particle-induced X-ray emission (PIXE)**

Particle-induced X-ray emission or proton-induced X-ray emission (PIXE) is a technique used in determining the elemental content of a sample from Na to heavier

**Figure 2.** *Schematic of RBS setup.*

**Figure 3.** *Typical ERDA setup.*

**Figure 5.** *Typical NRA setup.*

elements. These incident beam particles (usually protons) expel internal shell electrons from the target atoms, which results in the emission of characteristic X-rays (**Figure 4**).

### **2.4 Nuclear reaction analysis (NRA)**

Nuclear reaction analysis (NRA) involves the study of sample by irradiating them with select projectile nuclei with very-high-energy ions to induce nuclear reactions in the target nuclei. Targeted samples undergo a nuclear reaction under resonance conditions for a sharply defined resonance energy. The reaction product is usually a nucleus in an excited state, which immediately decays, emitting ionizing radiation that can be analyzed and interpreted (**Figure 5**).

## **3. Experiment detail**

### **3.1 Sample preparation of tobacco**

A sum of 19 different commonly sold cigarette brands (locally manufactured (8) and imported (11)) were randomly purchased from the market of Islamabad (**Table 3**).

**91**

**Table 1.**

*Analytical results for NIST 1515 (μg/g).*

*Investigation of Toxic Metals in the Tobacco of Pakistani Cigarettes Using Proton-Induced X-Ray…*

Two cigarettes were taken from a pack of each brand, and then tobacco was separated from paper and filter. The samples of tobacco were air dried for the removal of moisture in the covered container. Each sample was placed in polyethylene vials to prevent the contamination. A fine homogeneous powder of dried samples was obtained by grinding in mortar and pestle. Pellets of 7 mm diameter and 2 mm thickness of this fine powder were produced by using a tabletop hydraulic press (pressure 120 kg/cm2

pellets were placed in desiccators. Then samples were put into 5 MV Pelletron Tandem Accelerator for analysis. The particle-induced X-ray emission (PIXE) was used for this investigation of toxic metals. The PIXE is a very effective and reliable technique for multi-elemental analysis of materials. The GUPIXWIN and Excel software were used for results and calculations. The standard reference material of 1515 apple leaves from

With the approach of atomic-based analytical strategies in the previous 40 years, proton-induced X-ray emission (PIXE) has set up a part of the advanced elemental investigation of various materials [14]. PIXE is a technique with a diverse

The pelletized samples were irradiated with a 3 MeV proton beam from the 5 MV Pelletron Tandem accelerator installed at Experimental Physics Lab, National Centre for Physics, Islamabad. A standard reference material, NIST 1515 (apple leaves, National Institute of Standards and Technology, USA), was taken as the analytical quality control. The analytical outcomes concurred well with the standard qualities (**Table 1**), confirming the steady quality of the analytical outcomes in this work. The collimated proton beam was of 2 mm diameter. Mylar, "funny" filter having 100 μm thick, was used during the measurements, and this reduced the count

**Elements Determined values Certified values** S 1557.8 ± 194 1800 Cl 545.9 ± 62 579 ± 23 K 13468.6 ± 2254 16,100 ± 1200 Ca 12,013.1 ± 1689 15,260 ± 1150 Cr 0.32 ± 0.057 0.3 Mn 52.9 ± 6.6 54 ± 3 Fe 78.5 ± 16.4 83 ± 5 Co 0.07 ± 0.053 0.09 Ni 0.76 ± 0.23 0.91 ± 0.12 Cu 6.2 ± 2.02 5.6 ± 0.24 Zn 15 ± 2.3 12.5 ± 0.3 Sr 22 ± 5.1 25 ± 2 Cd 0.04 ± 0.007 0.013 ± 0.002 Sb 0.019 ± 0.008 0.013 Hg 0.14 ± 0.15 0.044 ± 0.004 Pb 0.61 ± 0.19 0.57 ± 0.024

NIST of the USA was used for calibration and analytical quality control.

array of applications in biology, geology, materials science, and others.

). The

*DOI: http://dx.doi.org/10.5772/intechopen.84723*

**3.2 PIXE analysis**

*Investigation of Toxic Metals in the Tobacco of Pakistani Cigarettes Using Proton-Induced X-Ray… DOI: http://dx.doi.org/10.5772/intechopen.84723*

Two cigarettes were taken from a pack of each brand, and then tobacco was separated from paper and filter. The samples of tobacco were air dried for the removal of moisture in the covered container. Each sample was placed in polyethylene vials to prevent the contamination. A fine homogeneous powder of dried samples was obtained by grinding in mortar and pestle. Pellets of 7 mm diameter and 2 mm thickness of this fine powder were produced by using a tabletop hydraulic press (pressure 120 kg/cm2 ). The pellets were placed in desiccators. Then samples were put into 5 MV Pelletron Tandem Accelerator for analysis. The particle-induced X-ray emission (PIXE) was used for this investigation of toxic metals. The PIXE is a very effective and reliable technique for multi-elemental analysis of materials. The GUPIXWIN and Excel software were used for results and calculations. The standard reference material of 1515 apple leaves from NIST of the USA was used for calibration and analytical quality control.
