A fourteen-day repeated dose oral toxicity study of APFO in rats.

Ammonium perfluoroocanoate (APFO) was repeatedly administered orally to male Crj:CD(SD)IGS rats for 14 days. Doses of APFO were 0, 0.5, 5, and 50 mg/kg. Significant increases and increasing tendencies in absolute/relative weight of the liver and no change in weight of the spleen were observed in all groups. Although inductions of mitochondrion- and peroxisome-specific enzymes were increased, no decrease was seen in any hematological parameter of lipid metabolism. Red blood cell count, hemoglobin concentration, and hematocrit or these tendencies showed a significant decrease or a tendency to decrease, but no influence on lymphocyte subsets was noted. Secondary inhibition of immunocompetent cells, previously reported for mice, was not seen in this study of rats.