Disappearance rate of ethanol from the blood of human subjects: implications in forensic toxicology

This article outlines major developments in knowledge about the human metabolism of ethanol. The results of a large number of controlled experiments aimed at measuring the rate of ethanol elimination from the blood are reported. The factors that influence the rate of ethanol elimination from blood, such as the amount of ethanol ingested, the drinking habits of the subjects, and the effect of food taken together with, or before, drinking were investigated. The slowest rate of ethanol disappearance was observed in a healthy male subject who ingested 0.68 g ethanol/kg body weight after an overnight (8 h) fast; the beta-slope was 9 mg/dL/h. The fastest rate of ethanol disappearance was observed in a male chronic alcoholic during detoxification; the beta-slope was 36 mg/dL/h. This four-fold difference in the rate of ethanol disposal should be considered when the pharmacokinetics of ethanol become an issue in drinking and driving trials, for example, when retrograde estimations are attempted.