Polycyclic aromatic hydrocarbons in the snow cover of protected areas of the Komi Republic

We studied the content of polycyclic aromatic hydrocarbons (PAHs) in snow cover of protected northern areas Komi Republic. PAHs in snow were determined by high-performance liquid chromatography. Insignificant PAHs levels in the range of 30–46 ng/L were found in the snow cover of protected areas. Naphthalene and phenanthrene were the main PAHs in the snow cover. Light PAHs were mainly present in dissolved form. The heavy PAHs in the snow cover were present in trace amounts and accumulated on the aerosol particles. Low toxicological activity was observed in all tested samples. The natural, non-pyrogenic origin of the PAHs was established on the basis of their diagnostic ratios. This may be an indication that PAHs enter the snowpack mainly through transformation of plant biomass and global air mass transport. The PCA showed a significant similarity of the PAH composition of all investigated sites. All the above facts allow relating the studied areas to background. It was found that the level of low-volatility PAHs entering the protected areas in 2023 is the same as the level of entering the background areas of the taiga zone of the Komi Republic in 2005–2007. The highest content of heavy PAHs and toxicological activity was found in the snow cover near the Yaksha settlement in the Pechoro-Ilychsky Reserve. Aerosol polyarenes were the main contributors to PAH toxicity. In comparison with low-intensity roads near the “Paraskiny Lakes” Reserve, it is shown that furnace heating has a greater effect on the PAHs composition in the snow cover.