New emerging polybromobiphenyls in serum of general population and their disruption on thyroid hormone receptor β1.

Abstract

After the PBBs pollution incident in Michigan, a large number of studies focused on the exposure of people to 2,2',4,4',5,5'-hexabromobiphenyl (BB-153), but paid less attention to other PBBs congeners in human serum. In this study, three monobromobiphenyls (BB-1, BB-2 and BB-3), five dibromobiphenyls (BB-4, BB-7, BB-9, BB-10 and BB-15), decabromobiphenyl (BB-209) and BB-153 in the serum of the general population in Wuxi from 2012 to 2016 were detected by GC-MS/MS. The most abundant congeners in serum samples were BB-1(median 254ng·g-1 lw), BB-10 (median 141ng·g-1 lw) and BB-209 (median 68.4ng·g-1 lw). The detection rate of BB-153 is less than 10%, and the concentration is far lower than that in other areas. The concentrations of BB-1, BB-10 and BB-209 are 3-4 orders of magnitude higher than the maximum concentration of BB-153. Serum concentrations of BB-209 increased significantly from 2012 to 2016 (p=0.025). In addition, the concentrations of BB-1 in serum of females were significantly higher than that of males, and the concentrations of BB-1, BB-10 and BB-209 in serum of young adults were significantly higher than that of middle-aged adults. Finally, we found that BB-1 and BB-10 may have similar disruption on the binding of T3 and TRβ1 as BB-153, while BB-209 has little effect on the binding of T3 and TRβ1. This suggests that we should pay more attention to the damage of BB-1 and BB-10 to thyroid in the future.