Bioaccumulation behavior of polybrominated diphenyl ethers (PBDEs) in the freshwater food chain of Baiyangdian Lake, North China

Polybrominated diphenyl ethers (PBDEs) are of great environmental concern due to bioaccumulation in different food chains. Trophodynamics of PBDEs in freshwater food chain is an important criterion for assessing their ecological risk. In the study, PBDEs were analyzed in sixteen aquatic species collected from Baiyangdian Lake, North China. The concentrations of nine PBDE congeners (BDE-28, -47, -66, -99, -100, -85, -153, -154, and -183) in aquatic organisms ranged from 3.4 to 160.2 ng/g lipid weight. BDE-47 was the predominant PBDE congener in most samples except for river snails and swan mussels. BDE-209 was detected in 50% of biota samples, which indicated the bioavailability of BDE209. Correlation between lipid-normalized concentrations of PBDEs and trophic levels determined by stable isotope nitrogen technologies confirmed that PBDEs were biomagnified in the freshwater food chain. The trophic magnification factors (TMFs) ranged from 1.3 to 2.1 for PBDE congeners, greater than one, indicating the biomagnification potential for the PBDE congeners in the freshwater food chain. The relationship between TMFs and Log Kow (octanol–water partition coefficient) indicated that the phenomenon of trophic magnification for lowly brominated congeners was obvious in the freshwater food chain.