Abstinence monitoring of suspected drinking drivers: ethyl glucuronide in hair versus CDT.

OBJECTIVE Ethyl glucuronide (EtG) determinations in the hair of self-reported teetotalers were reviewed and compared with carbohydrate-deficient transferrin (CDT) blood tests (by immunochemistry and high-performance liquid chromatography [HPLC]). METHODS A retrospective study was carried out on 154 people whose fitness to drive had to be assessed because of the suspicion of relevant alcohol problems. RESULTS EtG was detected in 55 percent of the hair samples and abstinence thus disproved. In two thirds (67%) of these cases, alcohol consumption was even shown to be excessive (EtG values > 30 pg/mg). Of the EtG-positive subjects 54 and 82 percent had CDT values within the reference range by immunochemistry and HPLC, respectively. Thirty-nine percent of the EtG-negative subjects had increased immunochemical CDT values; in contrast, 96 percent had HPLC CDT values within the normal range. CONCLUSIONS EtG analysis in hair is a useful tool for assessing fitness to drive in suspected drinking drivers; compared to CDT values it provides a direct and unequivocal marker for reliable abstinence monitoring over a period of several months, depending on the length of the hair.