Utility of Commercial Ethyl Glucuronide (EtG) and Ethyl Sulfate (EtS) Testing for Detection of Lighter Drinking Among Women of Childbearing Years.

ABSTRACT

OBJECTIVE: Even moderate alcohol consumption during pregnancy can pose risks to the fetus, making reliable and consistent detection of drinking in pregnancy critical. Ethyl glucuronide (EtG) and ethyl sulfate (EtS) have shown some ability to detect lower levels of drinking, but the sensitivity of commercial EtG/EtS testing to lower levels of drinking among women of childbearing age is unknown. This study sought to determine the ability of an EtG/EtS algorithm, as well as EtG alone, to detect alcohol consumption in women of childbearing age using commercial testing and cutoffs. METHOD: Ten women (ages 21-39 years of age) were administered one, two, or three standard drinks in separate sessions. Urinary EtG/EtS was measured at baseline and again at five timed intervals for 72 hours following each session. Samples from the first five participants used a commercial algorithm in which a positive test was EtG > 100 ng/ml and EtS > 25 ng/ml; samples from the next five participants were considered positive if only EtG was >100 ng/ml. RESULTS: All samples were positive at the 12-hour follow-up. By 24 hours, sensitivity for one standard drink was poor for the combined EtG/EtS assay as well as for EtG alone (20% detection) and modest for two standard drinks (40% detection). There were no positive EtG results after 36 hours. CONCLUSIONS: The EtG/EtS cutoffs used in the present study, which are representative of those used by commercial laboratories, were not sensitive enough to reliably detect light to moderate drinking beyond a 12-hour window among women of childbearing age.