ROLE OF CHEMICAL-SPECIES AND EXPOSURE CHARACTERISTICS IN CANCER AMONGPERSONS OCCUPATIONALLY EXPOSED TO CHROMIUM COMPOUNDS

Epidemiologic studies on chromate workers are considered with special reference to the valency of chromium compounds, carcinogenic potency, and water solubility. It is assumed that all hexavalent chromium compo unds are carcinogenic to humans when inhaled but that there is no evid ence that trivalent compounds are carcinogenic. It is suggested that z inc chromate is a highly potent carcinogen and also that calcium chrom ate may be carcinogenic. There are indications that chromates of low w ater solubility may be less potent carcinogens than compounds of great er solubility. Evidence is also presented for possible interactions wi th smoking and other factors involved in work-related cancers.