Evaluation of the chronic toxicity and carcinogenicity of perfluorohexanoic acid (PFHxA) in Sprague-Dawley rats.
Perfluorohexanoic acid (PFHxA), a 6-carbon perfluoroalkyl (C6; CAS # 307-24-4), has been proposed as a replacement for the commonly used 8-carbon perfluoroalkyls: perfluorooctanoic acid and perfluorooctane sulfonate. PFHxA is not currently a commercial product but rather the ultimate degradation product of C6 fluorotelomer used to make C6 fluorotelomer acrylate polymers. It can be expected that, to a greater or lesser extent, the environmental loading of PFHxA will increase, as C6 fluorotelomer acrylate treatments are used and waste is generated. This article reports on a chronic study (duration 104 weeks) that was performed to evaluate the possible toxicologic and carcinogenic effects of PFHxA in gavage (daily gavage, 7 days per week) treated male and female Sprague-Dawley (SD) rats. In the current study, dosage levels of 0, 2.5, 15, and 100 mg/kg/day of PFHxA (males) and 5, 30, and 200 mg/kg/day of PFHxA (females) were selected based on a previous subchronic investigation. No effects on body weights, food consumption, a functional observational battery, or motor activity were observed after exposure to PFHxA. While no difference in survival rates in males was seen, a dose-dependent decrease in survival in PFHxA-treated female rats was observed. Hematology and serum chemistry were unaffected by PFHxA. PFHxA-related histologic changes were noted in the kidneys of the 200-mg/kg/day group females. Finally, there was no evidence that PFHxA was tumorigenic in male or female SD rats at any of the dosage levels examined.
Department of Environmental Health, Indiana University, Bloomington, Indiana, USA jklauni@indiana.edu.
James E
JE
Klaunig
AGC Chemicals, Asahi Glass Com., Ltd., Ichihara-shi, Chiba, Japan.
Motoki
M
Shinohara
Daikin Industries, Ltd. Chemicals Division EHS Department, Settsu, Osaka, Japan.
Hiroyuki
H
Iwai
WIL Research, Ashland, Ohio, USA.
Christopher P
CP
Chengelis
WIL Research, Ashland, Ohio, USA.
Jeannie B
JB
Kirkpatrick
Department of Environmental Health, Indiana University, Bloomington, Indiana, USA.
Zemin
Z
Wang
Research Pathology Associates, LLC, Clemson, South Carolina, USA.
Richard H
RH
Bruner
D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002208:Caproates / Q000633:toxicity*; D015197:Carcinogenicity Tests; D002273:Carcinogens / Q000633:toxicity*; D004435:Eating / Q000187:drug effects; D005128:Eye Diseases / Q000139:chemically induced / Q000473:pathology; D005260:Female; D005466:Fluorocarbons / Q000633:toxicity*; D053208:Kaplan-Meier Estimate; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D016019:Survival Analysis
D002208:Caproates; D002273:Carcinogens; D005466:Fluorocarbons; C479228:perfluorohexanoic acid
fluorocompounds; perfluorohexanoic acid (PFHxA); rat chronic exposure