Perfluoroctan-Säure
Toxicity
and Toxicokinetics of Perfluorooctanoic Acid in Humans and Animals
Naomi Kudo and Yoichi Kawashima
Department of
Toxicology and Applied Pharmacology, Faculty of Pharmaceutical Sciences
Josai University,
1-1 Keyakidai, Sakado, Saitama 350-0295,Japan
Abstract -
Perfluorooctanoic acid (PFOA) is an octanoic acid derivative to which all
aliphatic hydrocarbons are substituted by fluorine. PFOA and its salts are
commercially used in various industrial processes. The chemical is persistent
in the environment and does not undergo biotransformation. It was reported that
PFOA ist found not only in the serum of occupationally exposed workers but also
general populations. Recent studies have suggested that the biological
half-life of PFOA in humans is 4,37 years based on study of occupationally
exposed workers. It is increasingly suspect that PFOA accumulates and affects
human health, although the toxicokinetics of PFOA in humans remains unclear. In
experimental animals, PFOA seems low in toxicity. PFOA is well-absorbed
following oral and inhalation exposure, and to a lesser extent following dermal
exposure. Once absorbed in the body, it distributes predominantly to the liver
and plasma, and to a lesser extent the kidney and lungs. PFOA is excreted in
both urine and feces. Biological half-life of PFOA is quite different between
species and sexes and the difference is due mainly to the difference in renal
clearance. In rats, renal clearance of PFOA is regulated by sex hormones,
especially testosterone. PFOA is excreted into urine by active tubular
secretion, and certain organic anion transporters are thought to be responsible
for the secretion. Fecal excretion is also important in the elimination of
PFOA. There is evidence that PFOA undergoes enterohepatic circulation resulting
in reduced amounts of fecal excretion. Elucidation of the mechanisms of
transport in biological systems lead to elimination and detoxification of this
chemical in the human body.