Chromium, one of the most common elements in the earth’s exists in several oxidation states (Cieslak-Golonka, 1996). The most important stable states are 0 (elemental metal), +III (trivalent), and +VI (hexavalent). The health effects and toxicity/carcinogenicity of chromium are primarily related to the oxidation state of the metal at the time of exposure. Trivalent (Cr[III]) and hexavalent (Cr[VI]) compounds are thought to be the most biologically significant (US Department of Health, 1993).
Chromium(VI) at high doses is considered to be the greatest health risk (Keegan et al., 2008). Cr(VI) enters the body by all three of routes of exposure: inhalation, ingestion or absorption through the skin.Breathing high levels of chromium(VI) can cause irritation to the nasal cavity, breathing difficulty (asthma and cough). Skin contact with certain chromium(VI) compounds can cause skin ulcers. Allergic symptoms such as redness and swelling of the skin have been reported following contacts with chromium compounds.
Hexavalent chromium is recognized as a human carcinogen via inhalation and known to cause lung cancer in humans (Quievryn et al., 2002). Deficiency of chromium has been associated with disturbed glucose tolerance, fasting hyperglycemia, glucosuria, increased body fat, dyslipidemia and impaired fertility (De Flora et al., 1995).