The accumulation, distribution, and toxicological effects of dietary arsenic exposure in lake whitefish (Coregonus clupeaformis) and lake trout (Salvelinus namaycush)

A 20-day experiment was conducted to compare the accumulation, distribution, and toxicolocical effects of dietary As, as arsenate, in lake whitefish (LWF, Coregonus clupeaformis) and lake trout (LT, Salvelinus namaycush). Results of this experiment were used to design an experiment of longer duration in which one of the fish species was selected and exposed three times per week to lower dietary As doses. In the present study each treatment group was exposed to a combination of one of three doses of As (0, 100, or 1000 mug As/g) and one of two types of diet, no brine shrimp (NS) or with brine shrimp (WS) for a total of eight dosing events. Brine shrimp were added to determine whether their presence enhanced consumption of As-contaminated food. Modified feeding behavior occurred in both fish species fed As contaminated diets, with the exception of the 100 mug As/g NS food. Brine shrimp addition did not affect feed consumption of the As contaminated diets. Significant As accumulation occurred in stomach., pyloric caeca, intestine, liver, kidney, and gallbladder, but not in bile or muscle. As exposure did not have a significant effect on hepatic and renal metallothionein concentrations. Concentrations of lipid peroxides were only significantly elevated in the plasma of LT fed the 1000 mug As/g WS food. Liver somatic indices decreased significantly in both species, whereas hematological parameters were not affected in either species. Mstological lesions occurred in gallbladder, liver, kidney, pyloric caeca and intestine from LWF These lesions were not observed in LT, however, gallbladders were not examined in this species. Weight gain was lower in both species fed As contaminated diets, however, condition factors were not affected. (C) 2002 Elsevier Science Inc. All rights reserved.