Contaminant sources, gastrointestinal absorption, and tissue distribution of organohalogenated pollutants in chicken from an e-waste site

Abstract

Several organohalogenated pollutants (OHPs), including polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), decabromodiphenyl ethane (DBDPE), and 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE) were examined in chicken dietary sources (soil and feed) and gastrointestinal contents (chyme, intestinal contents, and feces), and in 11 chicken tissues (liver, muscle, heart, lung, fat, brain, stomach, intestine, ovary/testis, kidney, and serum) from an e-waste recycling site in South China. Elevated levels of OHPs were found in the soil and chicken tissues. Soil was a more important source of OHPs, especially brominated flame retardants, than feed. In general, more-halogenated chemicals were less readily absorbed in the gastrointestinal tract. With the exception of the brain and serum, where lower concentrations occurred, no significant differences in PCBs, PBDEs, and BTBPE were found among the chicken tissues. DBDPE was detected mainly in the stomach, intestine, kidney, and ovary. Compared with the soil, all the tissues had lower proportions of CBs 52 and 101. PBDEs were dominated by BDE 209 in the soil and chicken feed; two different PBDE congener profiles, dominated by both BDE 183 and BDE 209 or dominated by BDE 209 only, were found in the chicken tissues except for the brain. Only BDE 47 or BDE 209 was occasionally detectable in the brain. DBDPE was also found in the brain samples despite its high log Kow values. The blood–brain barrier alters patterns of contaminant composition and results in lower levels of OHPs in the brain.