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Hexavalent Chromium

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Hexavalent Chromium Hexavalent Chromium: Summary of Health and Environmental Effects This one-page fact sheet has been developed by TURI to help Chronic (Long-Term) Health Effects Massachusetts companies, community organizations and The International Agency for Research on Cancer residents understand the chemical’s use and health and (IARC) classifies hexavalent chromium compounds in environmental effects. Group 1 (carcinogenic to humans). In contrast, trivalent Overview chromium compounds are Group 3 (not classifiable with regard to carcinogenicity to humans). The hazards of hexavalent chromium compounds are Exposure to hexavalent chromium is associated with significantly different from those of non-hexavalent 2 chromium compounds. Hexavalent chromium lung cancer and nasal and sinus cancer. Exposure can compounds are confirmed human carcinogens, also cause damage to the nasal mucous membrane, mutagens and developmental toxicants and have high perforation of the nasal septum, and asthma. If inhaled acute toxicity. Non-hexavalent chromium compounds through the mouth, it can cause periodontitis and do not pose the same level of concern with regard to gingivitis. either chronic or acute toxicity. Impacts of chronic hexavalent chromium skin exposure Until 2011, all chromium compounds were treated as a include dermatitis, hypersensitivity reactions, eczema, single category under TURA. Starting in reporting year and kidney or liver damage. The characteristic lesions 2012, hexavalent chromium compounds are reportable resulting from hexavalent chromium exposure are referred to as "chrome holes" or "chrome ulcers." as a separate category under TURA. The hexavalent 3 chromium compounds category has been designated as Chronic eye exposure can result in conjunctivitis. a Higher Hazard Substance under TURA, so the Hexavalent chromium is a mutagen, a developmental reporting threshold is 1,000 lb/year. toxicant, and a renal toxicant.4 5 6 Terminology Both hexavalent chromium compounds and non- Chromium exhibits a wide range of possible oxidation hexavalent chromium compounds are recognized by the Association of Occupational and Environmental states (or "valence states"), ranging from chromium(-II) 7 to chromium(VI). Clinics (AOEC) as asthmagens. Chromium compounds are stable in the trivalent state 1Agency for Toxic Substances and Disease Registry (ATSDR), (III or +3) and occur in nature in ores, such as Toxicological Profile for Chromium. ATSDR, September 2012. Available ferrochromite. at http://www.atsdr.cdc.gov/toxprofiles/TP.asp?id=62&tid=17. 2 National Institute for Occupational Safety and Health (NIOSH), Criteria The hexavalent (VI or +6) form is the second most for a Recommended Standard: Occupational Exposure to Hexavalent stable state. Hexavalent chromium rarely occurs Chromium. NIOSH Publication No. 2013 – 128, January 2013. Available at http://www.cdc.gov/niosh/docs/2013-128/pdfs/2013_128.pdf. naturally; it is usually produced from industrial 3 ATSDR 2012. activity. 4 www.expub.com; 6 RTECS citations found under ‘Mutation Data.’ 5California Safe Drinking Water and Toxic Enforcement Act of 1986 Acute (Short-Term) Health Effects (Proposition 65), http://oehha.ca.gov/prop65/prop65_list/newlist.html 6 EPA Toxicological Review of Hexavalent Chromium, (CAS No. 18540- Hexavalent chromium exposure has been documented 29-9), In Support of Summary Information on the Integrated Risk to cause several short-term and intermediate effects Information System (IRIS) August 1998. http://www.epa.gov/iris/toxreviews/0144tr.pdf including, but not limited to, respiratory irritation, 7 Association of Occupational and Environmental Clinics Asthmagen nosebleeds, asthma, sensitization, skin burns and List: http://www.aoecdata.org/ExpCodeLookup.aspx 1 dermatitis. The Toxics Use Reduction Institute is a research, education, and policy center established by the Massachusetts Toxics Use Reduction Act of 1989. University of Massachusetts Lowell 600 Suffolk Street, Suite 501 Lowell, Massachusetts 01854-2866 Ph: (978) 934-3275 Fax: (978) 934-3050 Web: www.turi.org Updated March 2013 .
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