ABSTRACT
Essential metals can have bene cial in uences on immune activities when present in appropriate concentrations, but can disturb the normal functions of the immune response when present in suboptimal amounts or in excess. Metal toxicants can also alter immune activities, in some cases depressing protective defenses against pathogens and biological toxins and in others producing excessive and damaging immune activities. The consequences of these alterations can be dramatic: conditions that diminish immune capacity can render an individual susceptible to signi cant
14.1 Introduction .......................................................................................................................... 379 14.2 Examples of Essential Metal In uences on Immune Mechanisms ......................................380
