Comparison of polychlorinated biphenyl profiles in rat, fish and human tissues; the effects of consuming Great Lakes fish
The food chain transfer of Polychlorinated Biphenyl (PCB) congeners was assessed in rat and human tissue after the consumption of contaminated Great Lakes fish. Fish from Lake Superior (LS), Lake Michigan (LM), and Lake Huron (LH) were examined for either total PCB or specific congener concentrations. Total PCBs were highest in carp, lake trout and siscowet lake trout compared to walleye, whitefish, and Pacific salmon. The profiles of individual congeners differed between the species, with whitefish containing tri- and tetrachlorobiphenyl congeners in the highest concentrations and lake trout and siscowet lake trout containing hexa- and heptachlorobiphenyls. Congeners 28, 47/48, 52, 66/95, 77/110, 118, 138, and 153 were found in most species. Lake, species, and the lake$\sp*$species interaction were determined to be the best predictors of PCB concentrations in fish using a MANOVA statistical model. Three studies were completed which fed adult male rodents fish as 30% of the total diet for 45 days, adult females for 90 days, and timed pregnant females throughout gestation and lactation. PCB congeners were transferred from the fish diets and were found in blood and brain tissue from the rats. PCB congeners found in brain tissue contained ortho substitutions, these included 28, 47/48, 49, 52, 118, 153 from all three rodent studies. Differences in PCB congeners were seen after 45 and 90 day exposure to the same diets, these differences are most likely due to an increased enzyme activity after the longer period of exposure, or alternatively may be due to differences between the sexes. No statistically significant differences regarding the accumulation of individual congeners in male and female pups from the developmental exposure could be determined. Human serum samples and epidemiologic information was collected from Native Americans residing on seven Great Lakes based reservations. The participants consumed lake trout, whitefish and walleye most frequently, and accumulated PCB congeners 138, 153, 170, and 180 in the highest concentrations. The consumption of one specific fish species was not significantly related to serum PCB concentrations; however, serum PCB were related to the consumption of LS fish. In addition, serum PCB concentrations were related to diabetes and liver disease. Many congeners were found in the fish, rat, and human tissues which are not included in routine analyses, these include PCBs 28, 47/48, 66/95, 77/110, and other higher chlorinated congeners mainly found in human serum such as 146, 194, 195/208, 196/203, and 206. A congener specific analytical approach should be implemented with respect to environmental PCB analysis. Previous attempts to create an environmentally relevant list are not adequate and, at a minimum, should also include the aforementioned list of congeners.
Health Sciences, Toxicology, Environmental Sciences
University of Illinois - Urbana-Champaign
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University of Illinois at Urbana-Champaign