[Peculiarities of exposure to polychlorinated biphenyls (PCBS) in the indigenous population of the coastal and mainland Chukotka].

The indigenous people of coastal areas show a low percentage of low chlorinated and dioxin-like PCB congeners (as opposed to mainland aborigines) with a significant proportion of the "triad" in the amount of PCBs. 5 years after the first survey the ratio of the analyzed groups of PCB congeners in the blood of parturients - mothers, as well as in the fetus - child in the coastal Chukotka remained unchanged, indicating that the equal share rate of clearance-accumulation of congeners and is almost equal share content of PCB congeners in the mother and child. The average duration of half-lives of PCB congeners (#105-187) from the mother's body was 4-6 years (for the sum of PCBs - 5.7 years), which is broadly consistent with the results of foreign studies. The composition of PCB congeners in the blood of the continental population significantly differs from those in the food, while coastal residents--similar to the composition of PCBs in marine mammals. The content of PCB congeners in the domestic sources of pollution has no resemblance to the composition of PCBs in the blood of the natives.