## 4 Results and Discussion
### PAH Toxicity
[52]:  
\[\text{RQ} =\text{C}_{\text{PAHs}}/\text{C}_{\text{QV}}\] \[\text{RQ}_{\text{NCs}} =\text{C}_{\text{PAHs}}/\text{C}_{\text{QV(NCs)}}\] \[\text{RQ}_{\text{MPCs}} =\text{C}_{\text{PAHs}}/\text{C}_{\text{QV(MPCs)}}\] \[\text{RQ}_{\sum\text{PAHs}} =\sum_{i=1}^{16}RQ_{i}(\text{RQ}_{i}\geq 1)\] \[\text{RQ}_{\sum\text{PAHs(NCs)}} =\sum_{i=1}^{16}RQ_{i(\text{NCs})}(\text{RQ}_{\text{Q(NCs)}}\geq 1)\]  
\[BaP_{MEQ}=\sum(C_{i}\;*\;TEF_{i})\]0 BaP toxic equivalent (TEQ), BaP mutagenic equivalent (MEQ) for studied sites. \[BaP_{MEQ}=\sum(C_{i}\;*\;TEF_{i})\]1  
where RQ: risk quotient; \(\text{C}_{\text{PAHs}}\): concentration of PAHs in environmental object, \(\text{C}_{\text{QV}}\): risk standard value of PAHs, NCs: negligible/minimum concentration, MPCs: maximum permissible concentration; \(\text{C}_{\text{QV(NCs)}}\): the normative value of the minimum concentration of PAHs generating negligible risk; \(\text{C}_{\text{QV(MPCs)}}\): the normative value of the maximum concentrations of PAHs given the maximum environmental risk (ng/L). The risk levels values were adopted from [52]. For individual PAHs:  
\(\text{RQ}_{\text{NCs}}=0\) means no risk,  
\(\text{RQ}_{\text{NCs}}\geq 1\) and \(\text{RQ}_{\text{MPCs}}<1\) means moderate risk,  
\(\text{RQ}_{\text{MPCs}}\geq 1\) means high risk. Regarding \(\text{RQ}_{\sum\text{PAHs}}\), values are interpreted as follows:  
\(\text{RQ}_{\sum\text{PAHs(NCs)}}=0\) means no risk;  
\(1\leq\text{RQ}_{\sum\text{PAHs(NCs)}}<800\) and \(\text{RQ}_{\sum\text{PAHs(MPCs)}}=0\) means low risk;  
\(\text{RQ}_{\sum\text{PAHs(NCs)}}\geq 800\) and \(\text{RQ}_{\sum\text{PAHs(MPCs)}}=0\) means moderate risk;  
\(\text{RQ}_{\sum\text{PAHs(NCs)}}<800\), \(\text{RQ}_{\sum\text{PAHs(MPCs)}}\geq 1\), means moderate risk;  
\(\text{RQ}_{\sum\text{PAHs(NCs)}}\geq 800\), \(\text{RQ}_{\sum\text{PAHs(MPCs)}}\geq 1\) means high risk. Currently, there are no standardized values for PAH pollutants in snow cover to assess environmental risk. Therefore, in accordance with [52] and [50], correspondence values of \(\text{C}_{\text{QV(NCs)}}\) and \(\text{C}_{\text{QV(MPCs)}}\) for water bodies were applied (Table 5). The results of calculated environmental risks in the case of PAH contamination of snow cover for the studied area are given in \[BaP_{MEQ}=\sum(C_{i}\;*\;TEF_{i})\]2 The obtained values displayed a high  
\begin{table}
\begin{tabular}{c c c c c c c c c c c c c c c c c c c} \hline \hline
**Site** & **PAH** & **Nap** & **Acy** & **Ace** & **Flu** & **Phe** & **Ant** & **Fla** & **Py** & **BlaL** & **Chry** & **BlbF** & **BlaL** & **BlaL** & **BlaL** & **BlghiP** & \(\Sigma\)**PAHs** \\ \hline \hline \multirow{11}{*}{1} & \multicolumn{3}{c}{CQV(NCs)} & \multirow{12}{*}{12} & 0.7 & 0.7 & 0.7 & 3 & 0.7 & 3 & 0.7 & 0.1 & 3.4 & 0.1 & 0.4 & 0.5 & 0.4 & 0.5 & 0.3 & \\  & \multicolumn{3}{c}{CQV(MPCs)} & \multirow{1}{*}{120} & \multirow{7}{*}{70} & \multirow{7}{*}{70} & \multirow{7}{*}{70} & \multirow{7}{*}{300} & \multirow{7}{*}{70} & \multirow{7}{*}{30} & \multirow{7}{*}{70} & \multirow{7}{*}{10} & \multirow{7}{*}{340} & \multirow{7}{*}{10} & \multirow{7}{*}{340} & \multirow{7}{*}{10} & \multirow{7}{*}{40} &level of environmental risk for Zawoja village. All of the individual PAHs showed at least moderate environmental risk, while the bolded ones were classified as high risk (Table 5). The main contribution is made by B[b]F, B[a]A, I [1,2,3-c,d]P, B[ghi]P, Pyr, BaP, Fla (in order with decreasing RQ values; Table 5), which for the majority of the sites, were classified as highly risky to the environment. Moreover, in all investigated sites, RQ\({}_{\Sigma\mathrm{PAHs}}\) revealed a high environmental risk with the maximum values recorded at sites 7 and 13 (>3000 ng/L) and the minimum at site 11. The environmental risks for Zawoja align closely with the values obtained from the snow samples in the city of Ivanovo [50], which indicates that the level of anthropogenic pressure in the winter season in this resort village is exceptionally high.