Excretion Profiles of Ethyl Glucuronide in Human Urine after Internal Dilution

Abstract

Ethyl glucuronide (EG) is a useful marker of alcohol consumption because its presence in urine can be detected up to five days. We investigated the impact of diuresis on the urinary excretion of EG, a minor ethanol metabolite. Seven healthy volunteers drank 250 mL of wine (25 g ethanol) in 15 min and, 240 min later, ingested 1 L of water within 15 min. Urine was voided before the drinking started and every 30-60 min for 400-550 min thereafter. Urinary ethyl glucuronide (UEG), creatinine, and ethanol were determined using liquid chromatography-tandem mass spectrometry, Jaffé's method, and the enzymatic ADH method, respectively. The maximum diuresis coincided with the lowest values of the UEG concentrations of 2 mg/L and the lowest creatinine values of 10 mg/dL 250-400 min after drinking. After drinking the wine, the urinary creatinine decreased slowly. After a short period of increasing, it decreased to minimum values caused by the water intake. After the intake of 1 L water, the diuresis increased within 60 min to its maximum. The amount of ethyl glucuronide excreted in urine was 10 mg (SD 5 mg) corresponding to 0.04% (SD 0.02%) of the dose administered. In successive voids during the elimination phase, the UEG and the diuresis were influenced after the subjects drank 1 L of water. Minimum UEG values of 0.5 mg/L could still be measured. Measuring UEG provides a reliable way to monitor recent drinking of alcohol. However, urinary creatinine needs to be measured additionally. Establishing a cutoff value of 25 mg/dL for urinary creatinine in diluted samples, like for the analysis of illicit drugs, is recommended. If the creatinine value is too low, the analyst has to decide about the further procedure.

A study of ethyl glucuronide in post-mortem blood as a marker of ante-mortem ingestion of alcohol

“…This was in accordance with an earlier study after the same dose of ethanol (n=6) (49), but lower than another study at a lower dose (n=7) (55). We further showed that somewhat less of the ingested ethanol was excreted as EtS (61) (not included in this thesis).…”

Stability of ethyl glucuronide in urine, post-mortem tissue and blood samples

“…Normalisation of urinary EtG concentrations to a 100-mg/dl creatinine concentration was useful in an earlier work to compensate for urine dilution [19][20][21] and is commonly used for EtG concentrations in urine. In this study, the creatinine concentrations of every fresh urine sample at the beginning of the storage experiment (t 0 ) were measured.…”

Involvement of UDP-Glucuronosyltransferases UGT1A9 and UGT2B7 in Ethanol Glucuronidation, and Interactions with Common Drugs of Abuse

“…Ethanol metabolism occurs primarily in the liver, mainly through oxidation catalyzed by alcohol dehydrogenases, aldehyde dehydrogenases, cytochrome P450 2E1, and catalase (Agarwal, 2001;Zakhari, 2006). Besides these pathways, glucuronidation by UDP-glucuronosyltransferases (UGTs) represents a minor detoxifying pathway for ethanol (,0.1% of complete alcohol elimination) (Jaakonmaki et al, 1967;Dahl et al, 2002;Goll et al, 2002). Ethanol itself is a good marker of alcohol consumption.…”