Distribution, Source and Ecological Risk Assessment of Parent and Alkylated PAHs in Coastal Environment of Dalian, China After Oil Spill

A total of 46 polycyclic aromatic hydrocarbons (PAHs, 21 parent and 25 alkylated) were determined in multi-matrices in Dalian's coastal area, China, 50 days after an oil spill accident. Principal component analysis-multiple linear regression (PCA-MLR) suggested that the transmission from spilled oil, atmospheric deposition, urban runoff, water-air exchange, wastewater treatment plants effluents, and water-sediment exchange could be the primary PAH contributors, accounting for 21.7%, 21.3%, 20.8%, 19.1%, 8.9%, and 8.1% of PAH concentrations, respectively. For sediment, pyrogenic source, and petrogenic source account for 60.0% and 40.0% of total PAHs emissions, respectively. Selected PAH levels in sediments were compared with Sediments Quality Guidelines for evaluation probable toxic effects on benthic organism and the results indicate that surface sediment from all sampling sites have a low to medium ecotoxicological risk. The mean effects range-median quotient and organic carbon-normalized analysis suggested that PAHs' combined ecological risk was generally low.