**5. The chemical composition of settled and suspended particulate matter**

The elemental EDX analyses were carried out on the micro-analytical system LINK AN 10 000 operating in secondary mode at a potential 25 kV. The energy-dispersion X-ray system provided preliminary information on the elemental composition of the samples. The EDX spectra were very similar for majority of collected particulate matter samples. Principal inorganic elements constituting the particles calcium, silicon, aluminium, potassium, iron, chlorine, magnesium as well as titan and manganese were confirmed. The EDX spectrum in Figure 10 represents the elemental chemical composition of the settled particulate matter sample.

Investigation of Suspended and Settled Particulate Matter in Indoor Air 469

**Figure 11.** EDX spectrum of elemental chemical analysis of suspended particulate matter

Aluminium 0.14 0.18 0.159 Silicon 0.33 0.37 0.350 Phosphorous 0.02 0.03 0.021 Sulphur 0.30 0.31 0.306 Chlorine 0.48 0.66 0.570 Potassium 0.25 0.37 0.310 Calcium 0.33 0.51 0.420 Titane 0.02 0.03 0.025 Cromium 0.01 0.01 0.010 Manganese 0.004 0.006 0.005 Iron 0.01 0.03 0.020 Zinc 0.01 0.01 0.01 Bromium 0.002 0.0007 0.0014 **Table 6.** The percentage of basic inorganic elements measured by XRF in settled particulate matter

Maximum [%]

Mean [%]

[%]

Element Minimum

**Figure 10.** EDX spectrum of elemental chemical analysis of settled particulate matter

The energy-dispersive X-ray system interfaced to the SEM provides preliminary information on the elemental composition of the samples. Figure 11 presents the EDX spectrum of the suspended particulate matter sample.

In all samples discussed here, the EDX spectra were very similar for majority of collected particulate samples. The principal inorganic elements constituting the particles in order of peak intensity decreasing were Ca Si O Al C Mg Fe Cl Na K. The presence of both carbon and oxygen, which can originate from organic compounds as well as from inorganic oxides, acids and/or salts, was confirmed [29].

The elements observed by EDX were confirmed also by using X- ray fluorescence analysis (XRF). The total amount of inorganic elements (except for carbon, oxygen and other elements with proton number under 11) in settled particulate matter measured by XRF was found very low and was about 2.23 %. In [30] organic carbon and elemental carbon made up 29 % and 2.5 % of the particulate matter, respectively. Water-soluble total carbon content in PM10 corresponds to 16% of the total particle masses measured in India. Organic matter is by far the major PM10 component besides mineral oxides. As observed in [31] major individual organic compounds quantified included series of alkanes, n-alkanoic acids, n-alkanals, alkan-2-ones and PAHs. Alkanes and ketones make up a significant fraction of particlephase organic compounds, ranging from C11 to C26, and C9 to C19, respectively. In addition, other organic compound classes have been identified, such as alkanols, esters, furans, lactones, amides, and nitriles [28]. The measured percentage content of measured elements is summarised in Table 6.

**Figure 10.** EDX spectrum of elemental chemical analysis of settled particulate matter

suspended particulate matter sample.

is summarised in Table 6.

inorganic oxides, acids and/or salts, was confirmed [29].

The energy-dispersive X-ray system interfaced to the SEM provides preliminary information on the elemental composition of the samples. Figure 11 presents the EDX spectrum of the

In all samples discussed here, the EDX spectra were very similar for majority of collected particulate samples. The principal inorganic elements constituting the particles in order of peak intensity decreasing were Ca Si O Al C Mg Fe Cl Na K. The presence of both carbon and oxygen, which can originate from organic compounds as well as from

The elements observed by EDX were confirmed also by using X- ray fluorescence analysis (XRF). The total amount of inorganic elements (except for carbon, oxygen and other elements with proton number under 11) in settled particulate matter measured by XRF was found very low and was about 2.23 %. In [30] organic carbon and elemental carbon made up 29 % and 2.5 % of the particulate matter, respectively. Water-soluble total carbon content in PM10 corresponds to 16% of the total particle masses measured in India. Organic matter is by far the major PM10 component besides mineral oxides. As observed in [31] major individual organic compounds quantified included series of alkanes, n-alkanoic acids, n-alkanals, alkan-2-ones and PAHs. Alkanes and ketones make up a significant fraction of particlephase organic compounds, ranging from C11 to C26, and C9 to C19, respectively. In addition, other organic compound classes have been identified, such as alkanols, esters, furans, lactones, amides, and nitriles [28]. The measured percentage content of measured elements

**Figure 11.** EDX spectrum of elemental chemical analysis of suspended particulate matter


**Table 6.** The percentage of basic inorganic elements measured by XRF in settled particulate matter

Chlorine, calcium, silicon, potassium and sulphur were found to be dominated; the concentrations of the other elements were quite lower as resulted from the quantitative XRF analysis (Table 6). The results of qualitative analysis by XRF correlated with those reported in [32]. The percentage of calcium and chromium measured by XRF is consistent with that measured by AAS (Table 9): 0.42 versus 0.43 % in case of calcium; 0.01 % by both XRF and AAS analysis in case of chromium. The XRF measured concentrations of iron and zinc were detected to be much lower than those detected by AAS (Table 9).

Investigation of Suspended and Settled Particulate Matter in Indoor Air 471

Absorbances associated with sulphate, nitrate, ammonium, aliphatic carbon-hydrogen, and carbonyl functional groups as main constituent of particulate matter were observed also in the FTIR spectra of diesel generated PM10 [35]. The mass concentrations of sulphate, nitrate, ammonium, organic carbon (OC), elemental carbon (EC) were primarily measured in [36] in

24% to the total mass in ambient PM10 as noticed in [37]. Compared to outdoors, indoor PM contained more silicate (36% of particle number), organic (29%, probably originating from human skin), and Ca-carbonate particles (12%) [38]. Indoor PM10 was elevated, chemically different and toxicologically more active than outdoor PM10 [38]. Suspended and settled particulate matter sampled in the child's bedroom was investigated in terms of mouse allergen in [39]. Airborne mouse allergen was detected in 48 of 57 (84%) bedrooms, and the median airborne mouse allergen concentration was 0.03 ng.m-3. The median PM10

The presence of selected metals in particulate matter samples was detected by atomic absorption spectrometry (SpectrAA-30, Varian, Austrália). Fe, Zn, and Cu were detected by a standard process in acetylene – air flame, Cd, Cr, Ni, Pb and Co were detected in graphite cell in the GTA 96 add-on equipment. Arsenic content was detected by hydride method in

Metals content was investigated in both settled and suspended particulate matter samples. Because of low quantity in the suspended particles samples, the metals concentrations were

The results of AAS analysis of selected metals content in settled and suspended aerosols for each monitored room are presented as metal concentrations in Tables 7 and 8. The average concentrations of metals measured in insufficient amount for individual concentration detection for each room are presented for arsenic, cadmium, chromium, nickel and lead.

Average concentration

Arsenic 0.10 Cadmium 0.03 Chromium 0.04 Nickel 0.05 Lead 0.09

**Table 7.** Surface metal concentrations in settled particulate matter [μg.cm-2]

Metal Kitchen Living room Working room Calcium 0.64 1.46 2.06 Copper 0.04 0.06 0.07 Iron 2.56 1.78 4.73 Magnesium 0.22 0.50 0.67 Zinc 0.29 2.80 0.91

**6. Metals content in suspended and settled particulate matter** 

, NO3- and SO42- concentrations represents a contribution of approximately

small particulate matter of size 0.1–3.0 μm.

concentration was 48 mg.m-3 [39].

the VGA 76 add-on equipment.

detected for TSP and PM10 filters all at once.

The sum of Cl-

The principal component analysis shows the existents of three associations of the elements in settling particles: a) lithogenic (As, Co, Cr, Fe, lantanides and Sc); b) biogenic (Sr and Ca); c) authigenic (U and Se). The average element enrichment factors were higher in the first period of settled particulate matter sampling from: Se (739)> Zn (523)> Cr(105)> Br(104)> Sb(97)> As (69) [33]. The As, Br, Cr, Sb, Se, Sr and U average concentrations in the settled particulate matter were measured higher than their average crustal abundances [33].

Qualitative estimation of various functional groups in particulate matter proceeded with Fourier transformed infrared analysis FTIR (Figure 12).

**Figure 12.** FTIR spectrum of settled particulate matter

Transmittances associated with particulate sulphate (near 618 and 1110 cm−1), ammonium (2900–3200, 1430 cm−1), hydroxyl (3200–3500 cm−1), aliphatic carbon (2920 and 2850 cm−1) and carbonyl (1650–1800 cm−1) functional groups were observed. FTIR also identified several organic functional groups, although specific organic molecules could not be identified. In addition, there was also noticed the presence of inorganic nitrate (835 cm−1) in [34]. Absorbances associated with sulphate, nitrate, ammonium, aliphatic carbon-hydrogen, and carbonyl functional groups as main constituent of particulate matter were observed also in the FTIR spectra of diesel generated PM10 [35]. The mass concentrations of sulphate, nitrate, ammonium, organic carbon (OC), elemental carbon (EC) were primarily measured in [36] in small particulate matter of size 0.1–3.0 μm.

470 Atmospheric Aerosols – Regional Characteristics – Chemistry and Physics

detected to be much lower than those detected by AAS (Table 9).

Fourier transformed infrared analysis FTIR (Figure 12).

**Figure 12.** FTIR spectrum of settled particulate matter

Chlorine, calcium, silicon, potassium and sulphur were found to be dominated; the concentrations of the other elements were quite lower as resulted from the quantitative XRF analysis (Table 6). The results of qualitative analysis by XRF correlated with those reported in [32]. The percentage of calcium and chromium measured by XRF is consistent with that measured by AAS (Table 9): 0.42 versus 0.43 % in case of calcium; 0.01 % by both XRF and AAS analysis in case of chromium. The XRF measured concentrations of iron and zinc were

The principal component analysis shows the existents of three associations of the elements in settling particles: a) lithogenic (As, Co, Cr, Fe, lantanides and Sc); b) biogenic (Sr and Ca); c) authigenic (U and Se). The average element enrichment factors were higher in the first period of settled particulate matter sampling from: Se (739)> Zn (523)> Cr(105)> Br(104)> Sb(97)> As (69) [33]. The As, Br, Cr, Sb, Se, Sr and U average concentrations in the settled

Qualitative estimation of various functional groups in particulate matter proceeded with

Transmittances associated with particulate sulphate (near 618 and 1110 cm−1), ammonium (2900–3200, 1430 cm−1), hydroxyl (3200–3500 cm−1), aliphatic carbon (2920 and 2850 cm−1) and carbonyl (1650–1800 cm−1) functional groups were observed. FTIR also identified several organic functional groups, although specific organic molecules could not be identified. In addition, there was also noticed the presence of inorganic nitrate (835 cm−1) in [34].

particulate matter were measured higher than their average crustal abundances [33].

The sum of Cl- , NO3- and SO42- concentrations represents a contribution of approximately 24% to the total mass in ambient PM10 as noticed in [37]. Compared to outdoors, indoor PM contained more silicate (36% of particle number), organic (29%, probably originating from human skin), and Ca-carbonate particles (12%) [38]. Indoor PM10 was elevated, chemically different and toxicologically more active than outdoor PM10 [38]. Suspended and settled particulate matter sampled in the child's bedroom was investigated in terms of mouse allergen in [39]. Airborne mouse allergen was detected in 48 of 57 (84%) bedrooms, and the median airborne mouse allergen concentration was 0.03 ng.m-3. The median PM10 concentration was 48 mg.m-3 [39].
