Inhalation Toxicity of an Isomeric Mixture of Hydrochlorofluorocarbon (HCFC) 225 in Male Rats

A blend of the hydrochiorofluorocarbon isomers HCFC-225ca andHCFC-225cb has been proposed as a potential substitute for CFC-113,an important solvent and cleaning agent. The toxicity followingrepeated inhalation of an HCFC-225 isomer mixture was assessedin male Crl:CDBR rats. Three groups of 10 male rats were exposedto the test compound in air at design concentrations of 500,5000,and 13,000 ppm. Rats were exposed 6 hr/day, 5 days/week for2 weeks. A control group of 10 male rats was exposed to aironly. Decreased serum cholesterol, triglycerides, and glucose;dose-related increased mean absolute and relative liver weights;and microscopic hepatocellular hy pertrophy were present atall exposure concentrations. Hepatocellular hypertrophy correlatedultrastructurally to proliferation of peroxisomes. Clinicalchemical parameters and organ weight and morphologic changesin the liver were reversible following 14 days of recovery.