Fluoride accumulation and toxicity in laboratory populations of wild small mammals and white mice

A laboratory experiment was conducted to compare the toxicological response and metabolism of inorganic fluoride by three species of wild mammals and laboratory white mice (Mus musculus L.). The experimental populations of the wild species—the short‐tailed field vole (Microtus agrestis L.), the bank vole (Clethrionomys glareolus L.) and the wood mouse (Apodemus sylvaticus L.)—were laboratory reared from wild stock, and all test animals were exposed to 0, 40 or 80 μg F ml⁻¹ in their drinking water for up to 84 days. The 40 and 80 μg F ml⁻¹ treatments induced premature mortalities in M. agrestis and C. glareolus only. Differential intakes, absorption and retention of fluoride were evident between M. musculus and M. agrestis, the two species subject to cage studies of fluoride metabolism budgets. Interspecific variation in accumulation of fluoride with time was also evident between all four species as regards the femur, molars and incisors. Severe dental lesions were apparent in species surviving the 80 μg ml⁻¹ treatment for 84 days. Overall, however, there were few clear differences in inherent species sensitivity to fluoride, the interspecific variation in metabolism and accumulation rates being attributable mainly to variation in intake.