Experimental Estimation of Widmark Factor in A Korean Male Population

Yoo, Seong Ho; Lee, Yoon Seong; Lee, Soong Deok

Abstract

The Widmark formula has been widely used in forensic fields since the early decades of 20 the century. When the calculation of blood-alcohol concentrations (BAC) from given quantities of alcoholic beverages consumed was required, Widmark equation has been applied. However, some modern experimental results have reported that the Widmark factor, r showed discrepancy between individuals. Furthermore, Widmark equation was derived from Caucasian to the calculation of blood alcohol concentration. To estimate and compare Widmark factor of blood with breath ethanol metabolism in Koreans, we performed the controlled drinking study for 50 healthy male. All subjects are classified into three groups considering alcohol-drinking history (frequency and quantity in the past year). Group A subjects (n=20) consumed 0.5 g ethanol per kilogram of body weight, group B subjects (n=18) 0.8 g, and group C subjects (n=12) 1.0 g in fast state, respectively. Biological specimens of blood and breath were obtained for alcohol experiment from 60 minutes to 6 hour every 30-60 minutes after the alcohol intake. Concentration-time profiles of alcohol were plotted for each subject and the Widmark values (C0 and r0) from blood and breath were extrapolated using linear regression analysis. We determined the practical factors, rpeak at peak blood alcohol concentration. The evaluated data of Widmark factor for Korean male are 1.19 (group A), 1.06 (group B), and 0.75 (group C), respectively, showing the unreliability and inaccuracy of Widmark formula to the male Korean population. Our findings suggest that Widmark equation could be applied only for gross approximation, and no accuracy must be offered.