Combined effects of xylene and alcohol on the central nervous system.

Ten healthy male students were exposed to m-xylene alone at concentrations of about 6 and 11.5 mumol/l and given a single dose of alcohol (0.4 and 0.8 g/kg) prior to exposure. The effects of these xylene concentrations and alcohol doses, as well as the combined effects of the two xylene concentrations with the higher alcohol dose on psychophysiological functions, such as body balance and reaction time, were assessed. Xylene alone did not significantly impair these functions, although there was a tendency towards impairment by the exposure to the higher xylene concentration. The impairment caused by alcohol alone was dose-dependent and exceeded that caused by xylene alone. The deleterious effects of xylene combined with alcohol were usually additive, although antagonism of alcohol effects on body balance by the higher xylene concentration was observed. The effects were pharmacodynamic rather than pharmacokinetic in nature.