The toxic properties of cadmium compounds have been well recognized in many species. There is little evidence to suggest a physiologic role for the metal. Rather, because of its long biologic half-life, cadmium acts as a cumulative poison, and even at quite low ambient concentrations, it can accumulate in mammals to values not insignificant in terms of critical toxic levels. The problem of cadmium toxicity has become especially important, as cadmium concentrations in the environment have begun to rise owing to a variety of human activities such as mining, the metallurgical industry, coal...