Bioaccumulation of Several Brominated Flame Retardants and Dechlorane Plus in Waterbirds from an E-Waste Recycling Region in South China: Associated with Trophic Level and Diet Sources

Abstract
The present study is primarily designed to examine the role played by dietary sources on polybrominated diphenyl ethers (PBDE) congener profiles in waterbirds collected in an e-waste recycling region in South China. Some emerging halogenated flame retardants (HFRs), such as dechlorane plus (DP), 2,3,4,5,6-pentabromoethyl benzene (PBEB), pentabromotoluene (PBT), and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), were also quantified. Stable isotopes (δ(15)N and δ(13)C) were analyzed to assess the trophic levels and dietary sources of the birds. PBDEs were found to be the predominant HFRs, followed by DP, PBT, PBEB, and BTBPE. The birds in which BDE209 was predominant have differential δ(13)C and δ(15)N signatures compared with other birds, suggesting that dietary source is one of the important factors in determining the PBDE congener profile in birds. The levels of ΣPBDEs, PBEB, and PBT were significantly correlated with the trophic level (δ(15)N) for avian species which are located in a food chain, indicating the biomagnification potential of these compounds. No correlation was found between DP concentrations and trophic level of the birds. There is a significantly negative correlation between the fraction of anti-DP and δ(15)N, suggesting that the metabolic capability of DP in birds increases with the trophic level of the birds.