Alcohol, Traffic, and Chemical Testing in the United States: A Résumé and Some Remaining Problems

Abstract

We give a résumé of "chemical testing" for alcohol in the United States in connection with traffic-law enforcement. Recent procedural and instrumental developments are briefly reviewed. Various factors involved in discrepancies between the results of analyses of near-simultaneous venous blood and breath specimens from the same subject are examined. Because the causes of these discrepancies cannot adequately be controlled in law-enforcement practice, we suggest that calculation of a blood-alcohol concentration based on the result of a breath analysis be abandoned. We recommend that when breath analysis is performed for law-enforcement purposes, the interpretation of the result should be statutorily based on the amount of alcohol found per unit volume of alveolar ("deep-lung") air. Serum or plasma of capillary blood is recommended as the sample when blood is to be analyzed.