Measurement of free and bound alcohol metabolites and methanol in human biological samples--free and bound alcohol metabolites and methanol in acute alcohol administration.

There are almost no studies on the in vivo distribution kinetics of free and bound ethanol, alcohol metabolites (acetaldehyde and acetate) or the related substance, methanol, during alcohol oxidation. Thus, an acute alcohol administration experiment (alcohol consumption experiment) was carried out using volunteers (five healthy adult males; 2 flushers, 3 non-flushers), and distribution kinetics were investigated in biological samples (blood and urine). The levels of alcohol metabolites and methanol were measured as free compounds in blood samples and bound and free compounds in urine samples. The results showed an increase over time of free alcohol metabolites in both the flusher and non-flusher groups, followed by a subsequent decrease. In addition, free methanol increased over time. Both bound alcohol metabolites and bound methanol were found to increase over time. Based on these findings, levels of free and bound alcohol metabolites and methanol in the biological samples were found to increase relative to levels before consumption in both the flusher and non-flusher groups. This is thought to be due to the binding of alcohol metabolites and methanol to biological components and increases during ethanol oxidation. It was concluded that this is the mechanism by which ethanol, alcohol metabolites and methanol accumulate in the body as a result of chronic alcohol consumption, suggesting that it may be possible to use these compounds as markers of consumption by measuring these compounds in biological samples taken from alcohol abusers or alcoholics.