Lead in wildlife and domestic animals: sources, risks and pathology
Mark A. Pokras
Tufts University, Cummings School of Veterinary Medicine
Conservation medicine examines linkages among the health of people, other animals and the environment. Few issues illustrate this better than lead (Pb) toxicity.
Lead poisoning is a significant problem for wildlife and domestic animals. We will review the biological and ecological effects of Pb in domestic and wildlife species, from cows to condors to earthworms. We will discuss sources of Pb (including mining, manufacturing, recycling, disposal and sporting and hobby uses). Clinical, subclinical and ecological issues will be addressed.
Lead is cheap and there is a long tradition of its use. But the toxic effects of Pb have been recognized for centuries. As a result, some societies have greatly reduced many uses of Pb, including many paints, gasolines and solders because of threats to the health of humans and the environment.
Despite our concerns, many Pb products are still available. In fact the U.S. uses more Pb today than at the peak of leaded gasoline. In the U.S. hunting, angling and shooting sports deposit more Pb into the environment each year than many industries.
Because of societal concerns, we know the most about Pb poisoning in people. Our knowledge about Pb poisoning in domestic and wild animals is significantly less. From an evolutionary perspective, physiological processes affected by Pb are well conserved. Thus, scientists are able to use rodents and fish to understand how Pb works in people. Similarly, those of us interested in safeguarding animal health should consider humans as excellent models for lead’s chronic and sublethal effects.
Given what we are learning about the many toxic effects of this heavy metal, there is every reason to develop and adopt non-toxic alternatives. To accomplish this, a broad, cross-species ecological vision is important. All interest groups must work together to find safe alternatives, to develop new educational and policy initiatives, to eliminate most current uses of Pb, and to clean up existing problems.
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Scheuhammer, AM and VG Thomas. 2011. Eliminating lead from recreational shooting and angling: relating wildlife science to environmental policy and regulation in North America. In: JE Elliott, et al. Wildlife Ecotoxicology:
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