Toxicology and Carcinogenesis Studies of Chlorinated Paraffins (C12, 60% Chlorine) (CAS No. 63449-39-8) in F344/N Rats and B6C3F1 Mice (Gavage Studies)

摘要

Toxicology and carcinogenesis assessments of chlorinated paraffins (C12, 60% chlorine), a material widely used as a flame retardant and extreme-pressure lubricant, were conducted in male and female F344/N rats and male and female B6C3F1 mice in single-administration, 16-day, 13-week, and 2-year studies. Doses used in the 2-year studies were 0, 312, or 625 mg/kg body weight per day administered by gavage in corn oil five times per week to groups of 70 male and female rats and 0, 125, or 250 mg/kg administered to groups of 50 male and female mice. Ten male and 10 female rats were killed after 6 and 12 months of dosing and examined for toxicity. Under the conditions of the 2-year gavage studies, there was clear evidence of carcinogenicity of chlorinated paraffins (C12, 60% chlorine) for F344/N rats based on increased incidences of hepatocellular neoplasms (primarily neoplastic nodules) in male and female rats, of adenomas or adenocarcinomas(combined) of the kidney tubular cells in male rats, and of follicular cell adenomas or carcinomas(combined) of the thyroid gland in female rats. Mononuclear cell leukemia in dosed male rats may have been related to administration of chlorinated paraffins (C12, 60% chlorine).