# Polychlorinated Biphenyls in the Snow Cover of South-Eastern Kazakhstan
## 3 Results  
Pollution of Snow Covers by Polychlorinated Biphenyls in Talgar City and Almaty City (2014 and 2015)  
For the determination of PCBs during the winter periods of 2014 and 2015, we took SC samples from the territory of the Institute of Geography of the Ministry of Education and Science of the Republic of Kazakhstan. This is located 25 km from Almaty in the central part of a large metropolis (the city of Almaty) and the satellite town of Talgar. At the same time, the task was to obtain real values of concentrations to provide an understanding of the PCB contamination level of solid precipitation within a densely populated area with developed infrastructure. The obtained results (Tables 1 and 2) show that the fresh solid precipitation in the territories of Almaty and Talgar cities is subject to PCB contamination. The absence of PCBs in snow samples was noted on January 29 and November 1, 2014, at both observation points, and on February 21 in the precipitation in Almaty. The highest concentrations of the toxicant were recorded at both points on December 8 of the same year: 0.8 \(\mathrm{\SIUnitSymbolMicro g}\)/L in the precipitation in Talgar and 3.79 \(\mathrm{\SIUnitSymbolMicro g}\)/L in Almaty. In 2015, the maximum PCB content of 0.33 \(\mathrm{\SIUnitSymbolMicro g}\)/L was found in the snow from Talgar and 0.65 \(\mathrm{\SIUnitSymbolMicro g}\)/L in the snow from Almaty. Increased levels of snow pollution at both sampling points were noted in December and January. The observed synchronism in the dynamics of the toxicant concentration in solid precipitations of Almaty and Talgar can be more clearly seen in Figure 2.  
Despite the general pattern of fluctuation synchronism of the toxicants, the level of PCB contamination in Talgar city in the 1 st quarter of 2014 was higher than in Almaty city. In the snow samples taken at the end of 2014 and during the first quarter of 2015, the toxicant concentration in Almaty was significantly higher than in the Taglar precipitation. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Indicators**} & \multicolumn{6}{c}{**Sampling Date**} \\ \cline{2-7}  & \multicolumn{6}{c}{**2014**} \\ \cline{2-7}  & **29.01** & **21.02** & **11.03** & **01.11** & **08.12** & **26.12** \\ \hline PCB congeners & Not found & 52; 66 & 52; 66; 138 & Not found & 52; 66 & 52; 66 \\ Total PCB, \(\mu\)g/L & Not found & 0.30 & 0.48 & Not found & 0.80 & 0.32 \\ \hline \multicolumn{7}{c}{**2015**} \\ \cline{2-7}  & \multicolumn{6}{c}{**22.01**} \\ \cline{2-7}  & \multicolumn{6}{c}{**22.01**} \\ \cline{2-7}  & \multicolumn{6}{c}{**22.02**} \\ \hline PCB congeners & 52; 66; 70 & 66; 82 & 66; 151 \\ Total PCB, \(\mu\)g/L & 0.33 & 0.19 & 0.12 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Content and congener composition of PCBs in solid precipitation in the territory of Talgar city. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Indicators**} & \multicolumn{6}{c}{**Sampling Date**} \\ \cline{2-7}  & \multicolumn{6}{c}{**2014**} \\ \cline{2-7}  & **29.01** & **21.02** & **11.03** & **01.11** & **08.12** & **26.12** \\ \hline PCB congeners & Not found & Not found & 66; 70 & Not found & 66; 118; 146 & 41; 44; 66; 70; 87; 101; 105; 110; 129; 151 \\ Total PCB, \(\mu\)g/L & Not found & Not found & 0.17 & Not found & 3.79 & 0.51 \\ \hline \multicolumn{7}{c}{**2015**} \\ \cline{2-7}  & \multicolumn{6}{c}{**22.01**} \\ \cline{2-7}  & \multicolumn{6}{c}{**22.02**} \\ \hline PCB congeners & 44; 66; 70; 74; 85; 87; 118; 146; 155 & 52; 66; 105; 110 & 66; 97; 137 & 66; 151 \\ Total PCB, \(\mu\)g/L & 0.65 & 0.66 & 0.19 & 0.19 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Content and congener composition of PCBs in solid precipitation in the territory of Almaty city. Figure 2: PCB content changes in the snow samples at the observation points of Almaty and Talgar cities. This is probably an indicator of more sources of PCB air pollution from numerous industrial enterprises, transport, municipal, and private emissions in Almaty.