Chromium carcinogenicity; a review of experimental animal data.

Since 1932 exposure to various hexavalent chromium compounds has been known to constitute a cancer hazard to industrial workers. A number of animal studies have been performed and chromates have been administered by inhalation, intratracheally, by intravenous and subcutaneous injection, intraperitoneally and orally. The human epidemiological studies have provided convincing evidence that zinc chromate is a potent carcinogen and there is some evidence that calcium chromate and chromium trioxide also constitute a cancer hazard in humans. The human studies have not selectively confirmed carcinogenic potency for other chromium compounds. The animal studies confirm the carcinogenic potency of calcium chromate and zinc potassium chromate and present strong evidence that chromates of lead and strontium are carcinogenic in animals. The significance of the water solubility for the carcinogenic potency of the chromates has not been clarified by animal studies.