Seasonal co-pollution characteristics of parent-PAHs and alkylated-PAHs in karst mining area soil of Guizhou, Southwest China

The research on polycyclic aromatic hydrocarbons (PAHs) in karst soil mainly focuses 16 kinds of parent-PAHs (p- PAHs), and little attention is given to alkylated-PAHs (a-PAHs) with higher concentration greater toxicity. Five surface soils coal mining area their surrounding areas were sampled as subject investigated, the spatiotemporal pollution characteristics p-PAHs a-PAHs analyzed discuss impact properties environmental conditions migration a-PAHs. results showed that southwestern area, especially was significantly compared p-PAHs, average 177.29 ± 37.36 ng/g; 346.87 104.91 PAHs presented a seasonal pattern winter > spring autumn summer. At same time, rainfall could affect change occurrence state soils, but effect weaker than forest 651.68 ng/g 755.38 ng/g, respectively, so they belonged contaminated soil, while concentrations two cultivated abandoned 475.51 367.58 370.63 belonging weakly contaminated. Toxicity assessment p-BaP maximum toxic equivalent 62.35 C 1 -BaP (42.09 ng/g), DaA (37.82 ng/g) 1-3 BaA (25.91 risk. correlation study organic carbon, clay calcium content dominant factors affecting distribution areas. can provide data guidance for management, control restoration areas, offer reference Guizhou province implement big-ecological strategy.