Source apportionment and probabilistic health risk assessment of polycyclic aromatic hydrocarbons in sediment from an urban shallow lake.

Abstract

Polycyclic aromatic hydrocarbons (PAHs) in sediment from urban shallow lake Bubanj (Serbia) were investigated in terms of their concentration, distribution, and potential effects on the environment and human health. The concentration of 16 PAHs (ΣPAHs) ranged from 24.4 to 107 ng/g dw. Low-molecular-weight PAHs (2- and 3-aromatic rings) were dominant, accounting for 71% of the total. Multivariate statistical analyses revealed that the main source of PAHs was the incomplete combustion of organic sources. Diagnostic ratios and positive matrix factorization (PMF) methods further indicated that combustion of organic matter and petroleum leakage were the dominant sources. The toxic equivalent quantity (TEQ) of ΣPAHs varied from 0.5 to 17.6 ng-TEQ/g-dry. BaP had the highest contribution to TEQ, followed by Ant, DahA, and BaA, with respective shares of 74.3%, 6.4%, 5.6%, and 5.3%. Dermal contact and ingestion were the primary exposure routes for PAHs, whereas inhalation posed negligible cancer risk. The incremental lifetime cancer risk (ILCR) values for adults were in the range of 3.9 × 10^-9-1.4 × 10^-7 and for children 5.3 × 10^-9-1.9 × 10^-7, indicating negligible carcinogenic health risks. Monte Carlo simulation showed that ILCR values for adults and children remained below the permissible limit of 1.0 × 10^-6, even at the 90th percentile.