90-Day Oral Gavage Toxicity Study of 8-2 Fluorotelomer Alcohol in Rats

8-2 fluorotelomer alcohol is a fluorinated chemical intermediate used to manufacture specialty polymers and surfactants. The potential subchronic toxicity and the reversibility of the effects of this chemical were evaluated following approximately 90 days of oral gavage dosing to Crl:CD®(SD)IGS BR rats. A complete toxicological profile, including neurobehavioral assessments and hepatic β-oxidation, were conducted at selected intervals and a group of rats was included for a 90-day postdosing recovery period. Dose levels tested were 0 (control), 1, 5, 25, and 125 mg kg. No test-substance-related mortality occurred at any dose level. Rats at 125 mg kg developed striated teeth, such that these animals were switched to ground chow at 77 days. No treatment-related alterations in body weight, food consumption, neurobehavioral parameters, or hematology clinical chemistry were found. Hepatic β-oxidation was increased in males at 125 mg kg and in females at 25 and 125 mg kg. In both males and females, plasma fluorine levels were increased at 125 mg kg and urinary fluorine was elevated at ≥5 mg kg. Degeneration disorganization of enamel organ ameloblast cells was observed at 125 mg kg in males, but not females. Liver weight increases accompanied by focal hepatic necrosis were observed at both 25 and 125 mg kg, and chronic progressive nephrotoxicity occurred in female rats at 125 mg kg. With the exception of hepatocellular necrosis in males at 125 mg kg and the increased incidence and severity of chronic progressive nephropathy in females at 125 mg kg, all other changes showed evidence of reversibility. The no-observed-adverse-effect level was 5 mg kg.