Deposition of ethyl glucuronide in WHP rat hair after chronic ethanol intake.

This study investigated the relationship between ethanol intake in rats and the resulting level of ethyl glucuronide (EtG) in rat hair. Rats (n = 50) consumed a 10% ethanol solution for 4 weeks, then EtG was extracted from samples of their hair using a novel extraction procedure involving freezing and thawing. The EtG concentration was measured using gas chromatography and mass spectrometry. The animals voluntarily drank ethanol, with daily consumption in most rats exceeding 5 g/kg b.w. The silylated EtG was stable for at least 28 h. The limit of detection was 0.03 ng/mg, and the limit of quantification was 0.1 ng/mg. Hair samples from rats that consumed ethanol had EtG levels ranging from 0.17-20.72 ng/mg in female rats and 0.15-13.72 ng/mg in males. There was a correlation between the amount of alcohol consumed and the EtG levels in hair from female (p < 0.01), but not male, rats. The method presented allows detection and quantification of EtG in rat hair. We also observed differences in EtG deposition in male and female rats.