INCREASED FREQUENCY OF ACETALDEHYDE-INDUCED SISTER-CHROMATID EXCHANGES IN HUMAN-LYMPHOCYTES TREATED WITH AN ALDEHYDE DEHYDROGENASE INHIBITOR

Acetaldehyde, the first metabolite of ethanol oxidation, in concentrations ranging from 100-mu-M to 400-mu-M caused a dose-dependent linear increase in the frequency of sister-chromatid exchanges (SCE) in cultured human peripheral lymphocytes. The SCE frequency was on an average 2-fold higher when the cells were exposed to the acetaldehyde after 24 h incubation instead of at the time of mitogen stimulation (0 h). When acetaldehyde was added together with the potent aldehyde dehydrogenase inhibitor 1-aminocyclopropanol (0.1 mM), the SCE response was significantly (p < 0.05) increased. The present results indicate that acetaldehyde is metabolized within human lymphocytes, and, moreover, that alcohol consumption during treatment with drugs that inactivate aldehyde dehydrogenase may cause a further increased incidence of acetaldehyde-induced SCE and concomitant lesions.