Quantitative aspects of spermatogenesis in rats and dogs after repeated hexachlorophene treatment

Hexachlorophene was administered orally, at subneurotoxic doses, to rats (5 mg/kg/day) and dogs (3 mg/kg/day) for 9 weeks: some of the rats and dogs were observed for a further 13 weeks. The serum concentrations of pituitary gonadotrophin and testosterone were unaffected in either species. No changes were induced in the testicular dimensions or semen characteristics of dogs and no macroscopic post mortem abnormalities, organ weight differences or lesions detectable by conventional light microscopy were found in their testes, pituitaries or secondary sex organs. A transient reduction in the number of germ cells counted in cross-sections of seminiferous tubules was seen in rats after 4 weeks treatment. After 9 weeks treatment, reduced spermatogonial counts were recorded in canine seminiferous tubules; in other respects spermatogenesis was proceeding normally. No delayed effects were apparent in eith species. It is concluded that repeated administration of hexachlorophene at subneurotoxic levels did not induce significant impairment of spermatogenesis in rats or dogs.