Brominated Flame Retardants, Polychlorinated Biphenyls, and Organochlorine Pesticides in Bird Eggs from the Yellow River Delta, North China

Concentrations of several persistent organohalogen compounds such as dichlorodiphenyltrichloroethane and its metabolites (DDTs), hexachlorocyclohexanes (HCHs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), decabromodiphenylethane (DBDPE), and polybrominated biphenyl 153 (PBB 153) were measured in eggs of six species of wild aquatic birds, one species of wild terrestrial bird, and two species of captive birds from North China. Among the contaminants measured, DDTs were the dominant compounds, HCHs and PCBs were in nearly the same concentration range, and PBDEs exhibited lower concentrations than other compound groups. The median concentrations of DDTs, HCHs, PCBs, and PBDEs in all avian species ranged from 21 to 11034, 5.5 to 623, 1.0 to 613, and 4.6 to 146 ng/g lipid wt, respectively. Median concentrations of DBDPE and PBB 153 in all avian species were in the range of not detectable (ND)-1.7 and ND-0.7 ng/g lipid wt, respectively. Significant differences among species in contaminant profiles and contaminant levels were found depending on their feeding habits, habitat and migration. The captive birds had the lowest contaminant levels and entirely different congener profiles in PCBs and PBDEs from those of wild birds, which can be attributed to differences in dietary compositions and reproduction rates. Octa- to deca-BDEs contributed more to the total PBDEs in wild terrestrial and captive birds than in wild aquatic birds, except for one insectivorous species, possibly due to greater exposure to terrestrial food sources. Preliminary risk assessment suggests that there is no risk of a reduction in offspring survival in avian species from North China due to organohalogen compounds, except for dichlorodiphenyldichloroethylene (DDE), which would be expected to affect some proportion of the populations of several species of birds studied.