Excretion of benzo[ a]pyrene and metabolites in urine and feces of rats: influence of route of administration, sex and long-term ethanol treatment

Abstract

The urinary and fecal excretion of benzo[ a]pyrene (B[ a]P) and its main metabolites were studied after oral and intraperitoneal administration of B[ a]P to male and female ethanol-treated and non-ethanol- treated rats. After oral administration of B[ a]P more mutagenic compounds as well as B[ a]P metabolites were found in feces than after intraperitoneal administration. The excretion of B[ a]P metabolites in urine and feces after oral administration were maximal at days 1 and 2 whereas after intraperitoneal administration excretion was maximal at days 2 and 3. In males, the amounts of excreted phenolic metabolites in urine and feces were generally higher than in females. The amounts of mutagenic products in urine and feces of males were also higher than in females after intraperitoneal and oral administration of B[ a]P. In urine of female rats that received B[ a]P intraperitoneally, a decreased excretion of phenolic metabolites was found after ethanol treatment. In feces of both male and female rats, a decreased excretion of 3-OH-B[ a]P was found after ethanol treatment. In this study, the influence of sex and administration route on the excretion of B[ a]P metabolites was more pronounced than the effect of ethanol treatment.