Exposure of remote maritime populations to coplanar PCBs.

Abstract

Two remote maritime populations were evaluated for their biological exposure to orgnochlorines in [1989][1990] Because of their high intake ofseafood, these two populations have high biological levels. One hundred nine breast milk samples from Inuit women from Arctic Quebec were analyzed to determine levels of polychlorodibenzo-p-dioxins (PCDDs), polychlorinated dibenzofrans (PCDFs), and coplanar polychlorinated bipheuWls (PCBs) including non-ortho, mono-oriho, and di-outho congeners. Total 2,3,7,-tetrachlorodibenzo-p-dioxin equivalents (TEqs) for PCBs were 3.5 times higher in Inuit milk samples than in 96 Caucasian milk samples. Amongthe 185 fishermen from the Lower North Shore ofthe Gulf of the St. Lawrence River, we evaluated 10 highly exposed fishermen for theircoplanar PCB blood levels. Total TEqs were 900 ng/kg for highly exposed individuals with 36 ng/kg for controls. In these two nonoccupationally exposed populations, coplanar PCBs make a larger contribution to the TEq than PCDDs and PCDFs. However, the mono-ortho penta CB No. 118 is the major contributor for the total toxicity.

Dioxin-like activity in the blood of Greenlandic Inuit and Danish women: a pilot study

“…In Canadian Inuit, the serum ratio of non-DL-PCBs (e.g., PCB-153) to the DL-PCB levels was higher than for Canadian Caucasians from the Arctic area (18,40). In the present study, among the 14 PCB congeners the plasma levels of 11 non-DL-PCBs and 3 mono-ortho-DL-PCBs (#105, #118, #156) were determined.…”

“…The latter group is made up of weak AhR ligands with very low or no TEF values, whereas di-ortho PCBs are non-DL-PCBs (15). The 3 most highly bioaccumulated di-ortho PCBs (138, Plasma dioxin-like activity in Greenlandic Inuit and Danish women 153, 180) make up to 55% of the total PCBs in human matrices (16,17) and they are found in Inuit breast milk and the blood of north shore fishermen in Arctic Quebec at concentrations between 10 and 30 times higher compared with Caucasian controls, respectively (18).The higher chlorinated PCBs have the potential to inhibit the AhR function (19,20). These results emphasize that assessment of the toxicological potential of a chemical mixture is much more complex than can be deduced by a given TEQ value.…”

HCH and DDT residues in molluscs from Chinese Bohai coastal sites

“…In addition, as OCPs are lipophylic and capable of being biomagnified, they could pose a serious threat to upper trophic levels of aquatic communities and potentially to humans. Many studies have reported that people consuming large amounts of contaminated seafood may have elevated concentrations of pollutants in their tissues compared with the general population (e.g., Asplund et al, 1994;Dewailly et al, 1994). From the human health viewpoint, the presence of OCPs in seafood should be of great concern due to their potential risks as they can cause a range of adverse human health effects, such as cancer, reproductive effects, and acute and chronic injury to the nervous system (Hayes et al, 1971).…”

Estimation of Target Hazard Quotients and Potential Health Risks for Metals by Consumption of Seafood in Taiwan

“…The consumption of these contaminated fish will exceed the risk-based concentration of ''zero'' recommended by the US EPA (1996). People consuming large amounts of contaminated seafood may have elevated concentration of heavy metals in their tissues compared to the general population (Asplund et al 1994;Dewailly et al 1994). A correlation between blood mercury levels and methylmercury exposure via fish consumption has been shown in several different studies (Grandjean et al 1992;Svensson et al 1992;Oskarsson et al 1996).…”