The decrease of blood alcohol concentration in drinking experiments and in double-sampling in forensic cases

The elimination of alcohol in man can be estimated by drinking experiments. From the experiments, described in the literature, a mean value of the decrease in blood alcohol concentration of about 0.15(per mille)/hr was calculated. In some forensic cases two blood samples are taken after an event. From these cases the mean value of decrease is computed by many authors at 0.18(per mille)/hr. This paper deals with the difference. The statistic evaluation of 466 alcohol curvatures of drinking experiments in man with short drinking times showed that in the 2nd and 3nd hours after the end of drinking the diminution in blood alcohol concentration during a period of about 1 hour was greater than in the time thereafter. This increased diminution has a mean value of about 0.18(per mille)/hr hr and can explain the difference in the results of drinking experiments and forensic cases, because the blood samples in forensic cases in question are normally taken during the 2nd and 3rd hours after the end of alcohol intake.