Metal concentrations in soil may be elevated considerably when metal‐laden sewage sludge is spread on land. Metals in earthworms (Lumbricidae) from agricultural fields amended with sewage sludge and from experimental plots were examined to determine if earthworms are important in transferring metals in soil to wildlife. Earthworms from four sites amended with sludge contained significantly (P < 0.05) more Cd (12 times), Cu (2.4 times), Zn (2.0 times), and Pb (1.2 times) than did earthworms from control sites, but the concentrations detected varied greatly and depended on the particular sludge application. Generally, Cd and Zn were concentrated by earthworms relative to soil, and Cu, Pb, and Ni were not concentrated. Concentrations of Cd, Zn, Cu, and Pb in earthworms were correlated (P < 0.05) with those in soil. The ratio of the concentration of metals in earthworms to the concentration of metals in soil tended to be lower in contaminated soil than in clean soil. Concentrations of Cd as high as 100 ppm (dry wt) were detected in earthworms from soil containing only 2 ppm Cd. These concentrations are considered hazardous to wildlife that eat worms. Liming soil decreased Cd concentrations in earthworms slightly (P < 0.05) but had no discernible effect on concentrations of the other metals studied. High Zn concentrations in soil substantially reduced Cd concentrations in earthworms.
In 1978-81, 293 bald eagles (Haliaeetus leucocephalus) from 32 states were necropsied and analyzed for organochlorine pesticides, polychlorinated biphenyls (PCB), and lead residues. DDE was found in all carcasses; PCB, DDD, trans-nonachlor, dieldrin and oxychlordane were next in order of percent frequency of detection. The median levels of DDE and PCB have declined when compared with previous collections. Five specimens contained high levels of dieldrin in their brains which may have contributed to their deaths. Seventeen eagles contained liver lead residues greater than 10 ppm and probably died of lead poisoning. Trauma and shooting are the most common causes of death.
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