Polycyclic Aromatic Hydrocarbons (PAHs) In The Upstream Rivers of Taihu Lake Basin, China: Spatial Distribution, Sources And Environmental Risk

Abstract The polycyclic aromatic hydrocarbons (PAHs) pollution in Taihu Lake Basin has caused widespread concern. However, the spatial temporal distribution of PAHs in the upstream rivers of Taihu Lake Basin remains largely unknown. Thus, this study aims to investigate the level, spatial distribution, sources and environment risk caused by PAHs in upstream rivers of Taihu Lake Basin. The concentrations of total 16 PAHs (∑16PAHs) ranged from 188.64 to 1060.39 ng/g, with an average of 472.62 ng/g. Compared with low-molecular-weight (LMW) PAHs, high-molecular-weight (HMW) PAHs were more resistant to degradation and easier to accumulate in the sediment. The results of source analysis demonstrated that the PAH pollution was mainly sourced from mixture of fuel combustion and direct petroleum spillage. The ecological risk assessment showed that moderate ecological risk caused by the PAH contaminants might occur in most sample sites. The incremental lifetime cancer risk (ILCRs) ranged from 2.07 ×10-4 - 2.66 × 10-3 for children and 9.66 ×10-5 - 1.24 × 10-3 for adult, indicating moderate cancer risk of PAH-contaminated sediments.