ABSTRACT
The focus of this chapter is on those elements for which there is limited or no evidence for essentiality and for which there is established or tenta tive evidence of an exposure hazard to one or more population groups in the United States. Aluminum, cadmium, and lead were chosen because they meet these criteria and because each interacts with several essential nutrients. Other toxic elements, such as arsenic, mercury, and tin, are of less practical concern in the United States today. The topics to be con sidered are based on an extensive literature. It is regretted that all relevant papers cannot be cited and that, in addition to recent publications, con siderable reference to reviews has been necessary.
