RESUMEN
AIMS: To determine the breath alcohol elimination rate (AER) and Widmark factor derived from the maximum breath alcohol concentration (r(peak BrAC)) in Chinese and Indians in Singapore, and to evaluate the contribution of genetic and non-genetic factors to variability of AER and r(peak BrAC). METHODS: A total of 180 subjects ingested a vodka-orange juice mixture, together with a standardized meal and underwent a series of BrAC measurements. RESULTS: Significant inter-ethnic differences in AER and r(peak BrAC) were observed in females and males, respectively. Alcohol dehydrogenase 1B (ADH1B) and acetaldehyde dehydrogenase (ALDH2) genotypes were identified as significant predictors for AER among males, accounting for 8.5% (P = 0.048) and 23.4% (P < 0.001) of the variance, respectively. ADH1B genotype was identified as a significant predictor for r(peak BrAC) among males, accounting for 17.1% of the variance (P = 0.001). In females, however, none of the genotypes were found to be significant predictors for breath AER, and r(peak BrAC). CONCLUSION: ALDH2 and/or ADH1B genotypes in males, but not in females, appear to contribute, albeit modestly, to variability in AER and r(peak BrAC). The median AER in Chinese males, Indian males, Chinese females and Indian females is 6.6 µg dl(-1) h(-1) [99% confidence interval (CI), 5.6-7.5 µg dl(-1) h(-1)], 6.2 µg dl(-1) h(-1) (99% CI, 5.5-7.0 µg dl(-1) h(-1)), 8.6 µg dl(-1) h(-1) (99% CI, 7.4-9.7 µg dl(-1) h(-1)) and 7.4 µg dl(-1 )h(-1) (99% CI, 6.2-8.4 µg dl(-1) h(-1)), respectively. The median r(peak BrAC) in Chinese males, Indian males, Chinese females and Indian females is 0.0229 (99% CI, 0.0216-0.0268), 0.0209 (99% CI, 0.0190-0.0237), 0.0214 (99% CI, 0.0185-0.0254) and 0.0199 (99% CI, 0.0187-0.0227), respectively.