1-Phenylethanol

1-Phenylethanol has a nongenotoxic mode of action responsible for the lung and liver tumors observed in mice following 2 years of inhalation exposure to ethylbenzene.1-Phenylethanol is one of the major primary phase-I metabolites of ethylbenzene. In principle it may yield an electrophilic intermediate by phase-II metabolism. Because of the extensive use of ethylbenzene as a solvent, 2-year carcinogenicity inhalation studies were carried out leading to renal hyperplasia and tubular neoplasms both in male and female rats and alveolar/bronchiolar neoplasms in male mice and hepatocellular neoplasms in female mice. Whereas the mechanism underlying the increased renal tumor incidences in rats has been clarified, the mechanism of tumor formation (genotoxic or nongenotoxic mode of action) in the lung and liver of mice is still unclear.