Polycyclic aromatic hydrocarbons and organochlorine pesticides in fish from Taihu Lake: Their levels, sources, and biomagnification

The investigation of biomagnification of polycyclic aromatic hydrocarbons (PAHs) and endosulfan, an organochlorine pesticide (OCP) and a new persistent organic pollutant, has been limited in freshwater food chains. The objective of the present study was to investigate the levels with focus on the sources and biomagnification of PAHs and OCPs in fish from Taihu Lake, China. In 193 samples of 24 species investigated, the concentrations ranged from 289 to 9 500 ng/g lipid weight (lw) for PAHs, and from 121 to 904 ng/g lw for OCPs, indicating that the fish in the lake was moderately contaminated. The PAHs mainly originated from both unburned petroleum and combustion of fossil fuels, and the OCPs from aged residues. It was unlikely that most of the PAHs and OCPs were biodiluted through the food chain because their trophic magnification factors were higher than one nevertheless the P-values >0.05. Aldrin, dieldrin, p,p′-DDE, p,p′-DDD, and endosulfan sulfate were significantly biomagnified through the food chain.

► The fish from Taihu Lake were moderately contaminated by PAHs and OCPs. The PAHs mainly originated from unburned petroleum and combustion of fossil fuels. ► The OCPs were old residues in Taihu Lake. ► Most of the PAHs/OCPs unlikely were biodiluted through the food chain in the Lake. ► A positive relationship was observed between TMFs and logKOW of PAHs and OCPs.