摘要：The biochemical approach in analysis of heavy metals toxicity is described in this review. Especially, the toxic actions of tin and zinc, essential metals, are introduced. Tin has some toxic effects on gastrointestinal function, blood cells, hepatic enzymes, endocrine secretion from pancreas, renal calcium metabolism and its related enzymes, bone metabolism, central nervous system, and reproduction function. The toxic studies of inorganic tin on various biochemical indices, however, suggest that the critical organ of tin is bone with a decrease in the femoral calcium content. Zinc has a wide variety of roles in mammalian system. However, the dose of zinc, which stimulates the mitochondrial function in liver cells, nervous function, and the growth and calcification of bone, exerts a porotic effect in bone. This effect on bone results from the decrease in serum calcium levels. On the basis of the sign of this manifestation, the toxic effect level of zinc is estimated to be lower than 1.0 mg Zn/kg. On the other hand, lead, cadmium, aluminium, manganease, and lithium also cause a disorder of calcium metabolism and its related bone metabolism. Accordingly, this review emphasizes that alteration of serum calcium level is important for the manifestation of toxicity of metals in various biochemical indices.
