Species Differences in Effect of Ethanol to Urinary Metabolites Excretion of Trichloroethylene in Mice and Rats

Kang, Eun Yong; Park, Jung Duck; Hong, Yeon Pye; Chang, Im Won

Abstract

This study was conducted to examine the species differences in the urinary excretion of trichloroethanol(TCE-OH) and trichloroacetic acid(TCA) of trichloroethylene(TCE) metabolites and the effect of ethanol on these metabolites in mice and rats. TCE administered to Male Sprague Dawley rats and ICR mice as a single oral dose(100, 200, 500, 1,000 or 2,000 mg/kg body weight) and ethanol(3.0 g/kg body weight) was taken orally 12 hours before TCE administration. The metabolites in urine were measured 0, 12, 24, 36 and 48 hours after TCE administration. The results of metabolite excretion were as follows; Total trichlorocompounds(TTC) in urine increased with TCE dose in mice while increased only below dose of 1,000 mg/kg TCE in rats. The net excretion of TCE metabolites was significantly greater in mice than rats, although the proportion of TCE-OH to TCA was not different between mice and rats. These findings indicate that mice were internally exposed to significantly higher concentration of TCE metabolites than rats and this trend appeared to be more prominent with the increase of TCE dose. Ethanol increased significantly TCE-OH in urine of rats while the increase of TCE-OH induced by ethanol was not significant in mice, and didn't increase TCA of urine in both of rats and mice. This result suggests that the effect of ethanol on TCE metabolism may be due to the increase of TCE-OH.