ABSTRACT
There are 72 elements in the periodic table that are clas sified as metals; of these, iron, mercury, lead, arsenic, barium, bismuth, and aluminum are of interest in toxi cology and are discussed in this section. Metals may exist in the elemental, inorganic, and organic forms. Some are essential for life, being vital parts of life processes, and significant disease results when they are deficient from body systems; others have no known bio logic function (1). Many are potent toxins. Metals that are essential nutrients can also exert toxic actions if the homeostatic mechanism maintaining them within phys iologic limits is unbalanced (2).
