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Pernis apivorus (Lumeij et al. 1985); king vulture, Sarcorhampus papa (Decker et al. 1979); and California condor Gymnogyps californianus (Janssen et al. 1986). The availability of Pb-based paints, discarded oil filters, used crankcase oil, Pb storage batteries, or pastures contaminated by industrial lead operations make Pb one of the most common causes of accidental poisoning in domestic animals (Demayo et al. 1982). Cattle and horses in the vicinity of a Pb smelter in California developed signs of Pb poisoning, and many died between 1880, when the smelter opened, and 1971, when the smelter closed (Burrows 1981). Of the mules used in the early mining of Pb, all died during their first year of service (Burrows 1981). Lead toxicosis has been reported in buffalos and cattle in India after they ate green fodder near a factory that recycled Pb from old batteries (Kwatra et al. 1986). Total milk yield declined sharply, and stillbirths and abortions increased significantly in cattle that ingested Pb-contaminated hay; the field from which the hay had been cut had a history of use for clay pigeon shoots and contained an estimated 3.6 tons of Pb shot pellets (Frape and Pringle 1984). In sheep grazing in areas near Pb mines, the frequency of abortions was high, and the learning behavior of the lambs was impaired (Demayo et al. 1982). Many species of zoo animals, including monkeys, fruit-eating bats, and parrots, have been fatally poisoned from ingestion of flaking Pb-based paint on the walls and bars of their cages (NRCC 1973). Ingestion of Pb-based paint chips was one cause of epizootic mortality of fledgling Laysan albatross, Diomedea immutabilis, at Midway Atoll in 1983 (Sileo and Fefer 1987). At present, there is no known dietary requirement for Pb in domestic animals, nor has it been shown unequivocally that Pb plays any beneficial role (NRCC 1973). On the contrary, Pb demonstrably and adversely affects weight, survival, behavior, litter size, and skeletal development (Tsuchiya 1979), and induces teratogenic and carcinogenic responses in some species of experimental animals (NRCC 1973; EPA 1980). Lead is not essential for plants, and excessive amounts can cause growth inhibition, as well as reduced photosynthesis, mitosis, and water absorption (Demayo et al. 1982). The decline of some European spruce forests has been attributed to excessive concentrations of atmospheric Pb (Backhaus and Backhaus 1986). Lead is toxic to all phyla of aquatic biota, though effects are modified significantly by various biological and abiotic variables (Wong et al. 1978). Wastes from Pb mining activities have severely reduced or eliminated populations of fish and aquatic invertebrates, either directly through lethal toxicity or indirectly through toxicity to prey species (Demayo et al. 1982). Health advisories warning anglers against eating Pb-contaminated fish have been posted in Missouri (Schmitt and Finger 1987). The significant increases in Pb concentration shown by marine corals between 1954 and 1980 were representative of the increases noted in other biota as a direct result of increased global Pb availability during that period (Dodge and Gilbert 1984). 3