THE UPTAKE AND EFFECTS OF LEAD IN SMALL MAMMALS AND FROGS AT A TRAP AND SKEET RANGE

This study was performed to evaluate the bioavailability and effects o f lead in wildlife at a trap and skeet range. The total lead concentra tion in a composite soil sample (pellets removed) was 75,000 mu g/g dr y weight. Elevated tissue lead concentrations and depressed ALAD activ ities in small mammals and frogs indicate that some of the lead deposi ted at the site is bioavailable. Mean tissue lead concentrations (mu g /g dry wt.) in white-footed mice (Peromyscus leucopus) at the range li ver = 4.98, kidney = 34.9, femur = 245) were elevated (P < 0.01) 5- to 64-fold relative to concentrations in mice from a control area. Tissu e lead concentrations in the only shorttail shrew (Blarina brevicauda) captured at the range (liver = 34.1, kidney = 1506, femur = 437) were elevated 35- to 1038-fold. Femur lead concentrations in green frogs ( Rana clamitans) at the range (1,728 mu g/g) were elevated nearly 1000- fold, and the lead concentration in a pooled kidney sample (96.2 mu g/ g) was elevated 67-fold. There was significant depression of blood ALA D activity in mice (P = 0.0384) and depression of blood and liver ALAD activity in frogs (P < 0.001). Hematological and histopathological le sions associated with lead toxicosis were observed in some animals. He moglobin concentrations were reduced 6.7% in mice (P = 0.0249), but he matocrit was not significantly affected in mice or frogs. Intranuclear inclusions were present in the renal proximal tubular epithelium of t wo of the mice and the shrew that were captured at the range, and necr osis of the tubular epithelium was also evident in one of the mice. Ki dney:body weight ratios were similar in range and control mice. Soil i ngestion may be a significant route of lead uptake in small mammals at the range. However, the tendency of lead to concentrate in the bones rather than in more by predators, especially raptors thar regurgitate undigestible material.