Human blood acetaldehyde concentration during ethanol oxidation (update 1982).

A wide variety of levels of human blood acetaldehyde have been reported in the past. During the last few years, however, it has become increasingly evident that most, if not all, of the previously observed acetaldehyde concentrations during normal (i.e., no deficiency in, or inhibition of, aldehyde dehydrogenase activity) ethanol oxidation merely reflected artefactual acetaldehyde formed during the analytical procedures. The artefactual acetaldehyde formation, which occurs mainly during blood protein precipitation, is effectively minimized by the recently improved PCA method in which blood is immediately mixed with a perchloric acid-saline solution, and by the semicarbazide method in which blood is treated with a fresh isotonic semicarbazide solution before removal of the plasma. Nevertheless, a procedure involving control blood with ethanol added should be employed to control for any artefactual acetaldehyde still produced. Based on the improved analytical procedures, no detectable acetaldehyde was found in the venous blood of Caucasian subjects after acute ethanol intake.