ABSTRACT
The earth’s crust is the ultimate source of all metallic elements found in the environment. Industrial products and used industrial material may contain high concentrations of toxic metals. For humans, the ingestion of food and food additives may represent the largest source of exposure to metals. In homeothermic, terrestrial vertebrates the effect of temperature variations are mediated by hormonal interactions, while in terrestrial invertebrates and plants it is through an increase in metal assimilation at higher temperature. The diurnal pattern of metabolism depends on light cycles rather than light intensity. Temperature and winds are a major influence on the rate and volume of movement of heavy metals, particulate matter, aerosols, or even vapor in the atmosphere. Anthropogenic sources of metal contamination to the terrestrial environment via the atmosphere includes fuel combustion, metal manufacture, foundries, refuse incineration, and cement production. The major environmental sources of arsenic are pesticides, herbicides, and other agricultural products.
