Beryllium is a probable human carcinogen, classified as weight-of-evidence Group B2 under the EPA Guidelines for Carcinogen Risk Assessment. Evidence on potential carcinogenicity from animal studies is 'Sufficient,' and the evidence from human studies is 'Inadequate.' It is considered highly likely that all soluble forms of beryllium including beryllium chloride, beryllium, fluoride and beryllium nitrate are carcinogenic in animals. These three soluble beryllium compounds are therefore assigned to weight of evidence Group B2. The potency factor (F) for beryllium is estimated to be 79.70 (mg/kg/day)(-1), placing it in potency group 2 according to the CAG's methodology for evaluating potential carcinogens. The bioassay used to calculate the potency factor for beryllium chloride, beryllium fluoride and beryllium nitrate suggests that these substances are highly carcinogenic (i.e., all treated animals developed tumors), but because there are no dose groups where the incidence is less than 100 percent there is no basis for calculating a specific potency factor.

Cover title. "June 1988." Includes bibliographical references. Microfiche.