Vitamins A1, A2, and E in minks exposed to polychlorinated biphenyls (Aroclor 1242®) and copper, VIA diet based on freshwater or marine fish

Abstract

Abstract Minks (Mustela vison) fed diets based on either freshwater fish or marine fish were exposed to 1 mg of polychlorinated biphenyls (PCBs) (Aroclor 1242®) daily for 28 d. To minks on the freshwater diet, copper (62 mg/kg food) was also given with or without PCBs. The marine diet (vitamin-rich plus additional supplements) included more vitamin A1 and E than the freshwater diet. We studied how the exposures affected levels of vitamins A1, A2, and E in liver and adipose tissues and levels of vitamins A1 and A2 in plasma. In females and males on the freshwater diet, the hepatic level of vitamin A2 was decreased because of the PCBs, and in these males the hepatic levels of vitamin E also decreased. Interestingly, with coexposure to PCBs and copper, the vitamin levels were, in general, close to the control values. In adipose tissues also, the PCBs induced significant changes in the concentrations of vitamins A1 and A2. In plasma, vitamins A1 and A2 were decreased in all patterns of exposure and on both diets. However, plasma thyroxine was slightly increased, a finding opposite to that reported previously in rodent studies. The results suggest that, in mink, diet greatly modulates the responses to PCBs, which may also differ in males and females. Furthermore, vitamins A1 and A2 may not be metabolized equally during PCB administration.