Hr mink bioaccumulation and toxicity of pcbs

MinkMustela vison is very sensitive to reproductive disorders induced by coplanar PCBs including reduced early life survivorship, kit weight, and litter size (Wren, 1991). Controlled feeding studies, including some with PCBs-contaminated fish from the Great Lakes (Aulerich, Ringer, and Iwamoto, 1973), demonstrated the toxicological effects of environmental mixtures of PCBs on mink reproduction (Jensen et al., 1977). Because these toxi-cities were related to chemical structure and varied greatly among structural classes of PCBs (Tillitt et al., 1996), it is likely that these responses are mediated through the AHR pathway.

Analyses of a small number of mink and river otter Lontra canadensis collected in 1982 and 1984 from locales adjacent to the HR revealed elevated burdens of PCBs; concentrations that exceeded those that cause reproductive disorders in ranched mink (Foley et al., 1988). NYSDEC news releases indicated that livers from mink and river otter collected near the HR between 1998 and 2000 near Hudson Falls and Troy, NY, exhibited fourteen-fold higher levels ofPCBs thanminkcollectedfromsites more distant from the river (NYSDEC, 2001). The mean level of PCBs in mink collected within 1 km of the river exceeded the EC90-effect level for health impairment (Smit et al., 1996).

A NYSDEC trapping survey compared the status of mink populations in close proximity and more distant from PCB-contaminated HR locales based on the fact that mink populations exhibit very limited home ranges and thus toxicological effects from contaminants would be spatially restricted. The survey suggests that mink populations are reduced in size near the PCB-contaminated section of the HR compared to those at reference sites.

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