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.