Chromium Exposure
Hexavalent chromium exposure
A complex and versatile metal, chromium was originally used in chemical production in the 19th century. "Chrome sores" were first noted in 1827 in two dyers who immersed their hands in potassium bichromate solutions. The first report of cancer in a chromate-exposed worker (a turbinate adenocarcinoma) was made in Scotland in 1890. Lung cancer was first reported among chromate workers in 1932 in Germany.
Today, hexavalent chromium compounds are widely used in the chemical industry as ingredients and catalysts, in steel and metal alloy production, in pigments, and in metal plating and chemical synthesis. Hexavalent chromium can also be produced when welding on stainless steel or Cr (VI)-painted surfaces.
The various forms of chromium behave differently in the body. Trivalent chromium is poorly absorbed through the skin, whereas the hexavalent form penetrates easily. Moreover, trivalent chromium is inhibited in passage through cell membranes. And although hexavalent chromium passes through cell membranes readily, it has a short intracellular life and reduces to the trivalent state within minutes to hours.
For these reasons, workers exposed to hexavalent chromium compounds have the most serious health effects. The major health consequences associated with exposure to Cr (VI) include lung cancer, nasal septum ulcerations and perforations, skin ulcerations, and allergic and irritant contact dermatitis. Occupational asthma and hematologic, liver and kidney toxicity may also come into play.
Workers with exposure to hexavalent chromium compounds should be strongly advised not to smoke, as smoking in a Cr (VI) working environment does increase the cancer risk.
