Alcohol Metabolites, Quantitative, Urine

Ethyl glucuronide (EtG) and ethyl sulfate (EtS) are the alcohol (ie, ethyl alcohol, ethanol) metabolites measured in this test.

EtG and EtS measurements are typically used to determine whether an individual has been exposed to alcohol (ethanol).

Accuracy of the test for alcohol metabolites detection purposes is greater when both EtG and EtS are included. EtG may be produced in vitro when ethanol-producing bacteria are present in the urine specimen. Conversely, we are not aware of published reports of in vitro production of EtS, even in the presence of ethanol-producing bacteria. So detection of EtS indicates in vivo alcohol presence, thereby improving the specificity of the test. We do not report a positive EtG result unless the EtS concentration is ≥100 ng/mL.

An EtG concentration <500 ng/mL is considered a negative result for alcohol metabolite. A concentration of ≥500 ng/mL is considered positive for alcohol presence only if the EtS concentration is ≥100 ng/mL. An EtS concentration <100 ng/mL is considered a negative result.

Yes, incidental exposure can cause a positive result. This LC/MS/MS method detects EtG and EtS regardless of the source (eg, alcohol consumption, medication patch containing a high concentration of ethanol, etc.). Therefore, we encourage you to interpret alcohol metabolite test results in light of the clinical picture.

EtG may be present in the urine for up to 80 hours after ethanol ingestion. EtS may be detectable for 24 hours or more after ingestion. These times depend on the cutoff used for the test and the patient’s metabolic rate and the time and duration of alcohol exposure.

Specimens are tested upon arrival at the laboratory and reported within 1 to 3 days.

Please refer to the Quest Diagnostics Test Center for the most recent information.

If you have any questions regarding this information or require assistance with interpreting these drug test results, please contact a Quest Diagnostics toxicology specialist at 1-877-40-RX TOX (1-877-407-9869). Specialists are available to assist you Monday through Friday from 8am to 6pm EST.