Evaluation of the chronic toxicity and carcinogenicity of perfluorohexanoic acid (PFHxA) in Sprague-Dawley rats

Toxicol Pathol. 2015 Feb;43(2):209-20. doi: 10.1177/0192623314530532. Epub 2014 May 28.


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.

Keywords: fluorocompounds; perfluorohexanoic acid (PFHxA); rat chronic exposure.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Body Weight / drug effects
  • Caproates / toxicity*
  • Carcinogenicity Tests
  • Carcinogens / toxicity*
  • Eating / drug effects
  • Eye Diseases / chemically induced
  • Eye Diseases / pathology
  • Female
  • Fluorocarbons / toxicity*
  • Kaplan-Meier Estimate
  • Male
  • Motor Activity / drug effects
  • Rats
  • Rats, Sprague-Dawley
  • Survival Analysis


  • Caproates
  • Carcinogens
  • Fluorocarbons
  • perfluorohexanoic acid