Accumulation and distribution of dietary uranium in lake whitefish (Coregonus clupeaformis).

We investigated the accumulation and distribution of uranium (U) in adult lake whitefish (Coregonus clupeaformis) fed a commercial diet containing 100, 1000 and 10000 µg U/g for 10, 30, and 100 days. No food avoidance or refusal occurred. The major sites of U accumulation were in the mineralized tissues, bone and scales, and in intestine, liver, kidney, and, in the highest treatment, gonads. Significant accumulation in fish fed 100 µg U/g was observed only in scales. Duration-dependent accumulation was observed in bone, scales, liver, and kidney of fish fed 10000 µg U/g and in scales of fish fed 1000 µg U/g. Dose-dependent accumulation was observed in scales of fish exposed for 100 days. U accumulation in gonads and gill peaked on day 30 when fish gonads were in the most advanced stage of maturation, of the sampling days evaluated. To evaluate the biological availability of U to fish inhabiting contaminated aquatic systems, analyses of U in scales, bone, intestine, kidney, and liver are recommended for biomonitoring programmes. The toxicology of U in these fish is described in the following manuscript (Cooley, H.M., Evans, R.E. Klaverkamp, J.F., 2000. Toxicology of dietary uranium in lake whitefish (coregonus clupeaformis) Aquat. Toxicol., 48, 393-413).