Results of Two-Year Toxicity and Reproduction Studies on Pentachlorophenol in Rats

Abstract

Male and female Sprague-Dawley rats were maintained on diets containing pentachlorophenol (PCP), characterized by a low content of nonphenolic impurities, for up to 24 months. Pentachlorophenol (PCP) was not found to be carcinogenic when administered to rats in their diet on a chronic basis at dose levels sufficiently high to cause mild signs of toxicity (1, 3, 10, or 30 mg/kg/day). Effects at the high dose level included decreased body weight gain (females), increased serum glutamic pyruvic transaminase activity (males and females), and increased urine specific gravity (females). An accumulation of pigment was observed in the livers and kidneys of females at 30 and 10 mg PCP/kg/day and males at 30 mg/kg/day. Ingestion of 3 mg PCP/kg/day or less by females and 10 mg/kg/day or less by males was not associated with significant toxicologic effects. To evaluate the effects on reproduction, rats were fed 3 or 30 mg PCP/kg/day for 62 days prior to mating, during 15 days of mating, and subsequently throughout gestation and lactation. A reduction in the mean body weight was observed among the adult rats at the highest dose level. Except for a significant decrease in neonatal survival and growth among litters of females ingesting 30 mg PCP/kg/day, measures of reproductive capacity were unaffected at both dose levels of pentachlorophenol. Ingestion of 3 mg PCP/kg/day had no effect on reproduction or neonatal growth, survival, or development.