Estimated lethal ethanol concentrations in relation to age, aspiration, and drugs.

In 98 deaths certified to be due to accidental alcohol poisoning, maximum antemortal blood ethanol concentrations were estimated as the sum of postmortal concentration and the product of blood ethanol elimination rate (0.258 g/liter/hr) and the time interval between the discontinuation of drinking and death. The estimated mean maximum concentration (g/liter) was 4.63 for uncomplicated cases, 4.26 for cases with heart disease, 3.98 for cases in which aspiration of stomach contents had contributed to death, 3.59 for ethanol-barbiturate poisonings, and 3.11 for combinations of ethanol and other psychotropic drugs. The mean for this last group was significantly lower than that for the first or the second group (p less than .001). The mean concentration for ethanol-barbiturate poisonings was signicantly lower than the mean for the uncomplicated cases (p = .01). In the two first groups combined, the higher the age, the lower the ethanol concentration (r = -.27; p = .02). Likewise, the postmortal blood ethanol concentration correlated negatively with age (r = -.26; p = .02), after controlling for the time interval. The lethal ethanol concentration for the aged seems to be lower than that for young people. A possible explanation for this phenomenon is the loss of ethanol tolerance.