ABSTRACT
The distribution of Cadmium (Cd) in the natural environment reflects its nature as a lithogenic element and its association with Zinc (Zn). Cadmium has several important applications and is found in a variety of products. Cadmium in contaminated soils and mine wastes is transferred into freshwaters via leaching and runoff. The effects of Cadmium on human health are known from occupational and environmental exposure. Chronic inhalation of particulate Cadmium in the workplace has been suspected of causing lung disease. Cadmium uptake by rice was enhanced by the low pH of the contaminated paddy soils. The ecotoxicity of Cadmium is an additional cause for concern; for example, in some parts of Europe, environmental concentrations exceed estimated adverse effect thresholds for terrestrial and aquatic ecosystems. Excess Cadmium uptake can affect respiration, transpiration and photosynthesis, with visible symptoms of leaf chlorosis and retarded growth. Some algal species bioaccumulate Cadmium.
