Metabolism reactions chromium toxicity

Chromium in the +3 oxidation state is an essential trace element (see Section 10.3) required for glucose and lipid metabolism in mammals, and a deficiency of it gives symptoms of diabetes mellitus. However, chromium must also be discussed as a toxicant because of its toxicity in the +6 oxidation state, commonly called chromate. Exposure to chromium(VI) usually involves chromate salts, such as Na2Cr04. These salts tend to be water soluble and readily absorbed into the bloodstream through the lungs. The carcinogenicity of chromate has been demonstrated by studies of exposed workers. Exposure to atmospheric chromate may cause bronchogenic carcinoma with a latent period of 10 to 15 years. In the body, chromium(VI) is readily reduced to chromium(III), as shown in Reaction 10.4.3 however, the reverse reaction does not occur in the body. 

Burrows D, ed. 1983. Adverse chromate reactions on the skin. In Burrows D, ed. Chromium Metabolism and toxicity. Boca Raton, EL CRC Press, Inc., 137-163. 

The behavior of metals as atoms or ions deeply affects the electrochemical reactions they undergo, and similarly affects the metabolism of plants and animals. Iron, copper, cobalt, potassium, and sodium are examples of metals that are essential to biological function. Some metals such as cadmium, mercury, lead, barium, chromium, and beryllium are highly toxic. 

Burgess WA (1981) Potential exposures in industry - their recognition and control. In Clayton GD, Clayton FE (eds) Patty s industrial hygiene and toxicology, 3rd edn, vol 1. John Wiley Sons, New York, pp 1149-221 Burrows D (1983) Adverse chromate reactions on the skin. In Burrows D (ed) Chromium metabolism and toxicity. CRC, Boca Raton, pp 137-163... 

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