Abstract
The limitation of legacy hexabromocyclododecanes (HBCDs) and increasing usage of emerging brominated flame retardant (BFR) tetrabromobisphenol A (TBBPA) resulted in their co-exposure to organisms. In this study, domestic chicken and environmental samples collected near a BFR manufacturing zone were analyzed to determine the bioaccumulation and transfer of HBCDs and TBBPA. The mean concentrations of ∑(3)HBCDs, TBBPA, ∑(4)TBBPA-related derivatives, ∑(9)TBBPA-related byproducts, and ∑(16)TBBPA-related transformation products in chicken tissues were 1207, 0.20, 15087, 0.96, and 6384 ng/g lipid weight, respectively. Exposure to sources of BFR contamination (soil, feed, and water) could be the main cause of high BFR levels in chickens. α-HBCD and bis-substituted TBBPA analogues have higher bioaccumulation factor levels than TBBPA and other compounds, indicating greater bioconcentration potential for substances with higher logK (ow). HBCDs, TBBPA, and TBBPA analogues tend to be enriched in the chicken comb and spleen and can cross the blood-brain barrier into the brain. However, while these compounds accumulate in the mother, they are also subject to metabolic processes that lead to their eventual excretion. Low-persistence BFRs were more favorable to maternal transfer, while compounds with high persistence tended to be retained in the mother. Although dietary intake of BFRs through chicken consumption poses a low risk to the general population, concerns remain regarding the synergistic risk of BFRs.