ABSTRACT
Trace elements are considered essential if their deficiency consistently results in impairment of function. Trace element deficiency may produce both specific as well as nonspecific effects. Trace element deficiency may produce both specific as well as nonspecific effects. Conversely, an excess of a trace metal, which arises either through a failure of intrinsic control mechanisms or through excessive exposure, may produce toxicity, which is either immediately apparent or latent and, ultimately of potential significance. Iron is known as an important component of porphyrin-based compounds which are bound in protein such as hemoglobin and myoglobin. In smaller amounts within the body tissue, iron is associated with enzymes and mitochondria which have significant metabolic functions. Zinc is a necessary element needed for the function of more than 70 enzymes from different species. The greatest concentrations of copper are in the liver and brain, with smaller amounts in the heart, kidney, spleen, and skeleton.
