EtG Alcohol Test: What It Is and What It Detects
An EtG alcohol test is a urine test that looks for ethyl glucuronide (EtG), a byproduct the body produces when it processes alcohol. Because EtG stays in urine long after ethanol itself has cleared, it can show alcohol use from roughly the past one to three days, and after heavy drinking sometimes longer.
For clinics, treatment centers, courts, probation offices and employers, that longer window is the reason EtG is used for abstinence monitoring. A breath test only shows whether alcohol is in the body right now. An EtG urine test can show whether someone drank since the last check-in.
What Is EtG on a Drug Test?
When you see EtG on a drug test panel, it is an alcohol biomarker, not a drug. A small fraction of the ethanol a person drinks is converted in the liver into ethyl glucuronide and a related marker, ethyl sulfate (EtS), and both are excreted in urine. Standard drug panels do not include alcohol, so EtG is usually added as a separate line or run as its own test.
The key point for program managers is that EtG is a direct metabolite of alcohol. It is more specific than older indirect markers, and it is not affected by how quickly a particular person clears ethanol from the bloodstream.
How Long Does Alcohol Stay in Urine?
It depends on what you test for. Ethanol itself usually clears from urine within about a day or less, so a standard alcohol urine test has a short window. EtG extends that window considerably.
- Ethanol in urine: typically hours, often up to about 12 hours after the last drink, depending on the amount consumed.
- EtG in urine: commonly 24 to 72 hours after moderate drinking. SAMHSA's clinical advisory notes that EtG can be detected up to about 80 hours after heavy drinking.
Body size, kidney function, hydration, the amount consumed and the test cutoff all affect these windows. Treat them as ranges, not guarantees. Lower cutoffs lengthen the detection window and raise the chance of picking up incidental exposure.
EtG Urine Test Cutoffs Compared
The cutoff is the most important setting in an EtG test. SAMHSA's advisory on alcohol biomarkers describes how results at different concentrations are commonly interpreted. Your medical director, legal counsel or program policy should decide which cutoff applies.
| Cutoff (ng/mL) | Sensitivity | General interpretation | Typical fit |
|---|---|---|---|
| 100 | Highest | Very low positive. May reflect drinking in the past 1 to 3 days, or recent incidental exposure. | Strict abstinence programs that can confirm and review results individually |
| 500 | Moderate | Low positive. Suggests drinking or significant exposure, and is less likely to reflect trace contact. | Treatment, probation and monitoring programs that want fewer incidental positives |
| 1,000 | Lower | High positive. Consistent with heavy drinking the previous day or lighter drinking the same day. | Programs that prioritize avoiding disputed results over catching light use |
Limits of an EtG Test Buyers Should Know
EtG is useful, but a positive result is not proof of intentional drinking on its own. Incidental exposure to ethanol in products such as alcohol-based hand sanitizers, some mouthwashes and certain foods or medications can produce low-level positives, particularly at the 100 ng/mL cutoff. SAMHSA's advisory cautions against using EtG results alone for punitive decisions.
Other limitations to plan around:
- Dilute urine can lower the concentration and produce a false negative.
- Bacterial contamination of a urine sample, for example in a urinary tract infection, can affect EtG levels, so sample integrity matters.
- Instant tests are screens. A presumptive positive should be confirmed by a laboratory method, such as LC-MS/MS, before any action is taken.
- EtG is not a DOT alcohol test. Under 49 CFR Part 40, DOT-regulated alcohol testing uses breath or saliva devices, not urine EtG. Do not substitute EtG in a federally regulated program.
Buyer's Checklist: Adding EtG to a Testing Program
- Define the purpose: abstinence monitoring, treatment compliance, court-ordered testing or a non-regulated workplace policy.
- Choose the cutoff in writing, and have the medical or legal reviewer approve it.
- Decide whether you need an instant screen, lab testing, or both, and set a confirmation protocol for every presumptive positive.
- Write a donor-instruction policy that addresses sanitizer, mouthwash and other incidental sources.
- Use a collection process with temperature and integrity checks to catch dilution or tampering.
- Document chain of custody if results could be used in a legal or employment decision.
- Confirm that your policy complies with applicable federal, state and local rules before rollout.
Sourcing EtG Testing Supplies
American Screening Corp supplies drug and alcohol testing products wholesale to clinics, hospitals, addiction-treatment centers, courts and probation departments, labs, staffing firms and employers. If your program pairs alcohol monitoring with a broader panel, you can review our urine drug test cups for multi-panel screening. Because EtG availability, formats and cutoffs vary, contact our team to confirm what fits your protocol, including lab confirmation options.
Frequently Asked Questions
What is EtG on a drug test?
EtG is ethyl glucuronide, a direct metabolite of alcohol that appears in urine after drinking. It is not a drug. It is added to or run alongside a drug panel to show recent alcohol use.
How long does alcohol stay in urine?
Ethanol itself usually clears within about 12 hours or less. EtG typically remains detectable for 24 to 72 hours, and up to about 80 hours after heavy drinking, depending on the individual and the cutoff.
Can hand sanitizer or mouthwash cause a positive EtG result?
Heavy or repeated incidental exposure can produce low-level positives, mainly at the 100 ng/mL cutoff. Higher cutoffs, donor instructions and review of low positives help reduce disputed results.
Is an EtG urine test accepted for DOT testing?
No. DOT alcohol testing under 49 CFR Part 40 uses breath or saliva testing, so urine EtG should not replace it in regulated programs. It may still be used in non-regulated programs where policy and law allow.
Sources
- SAMHSA: The Role of Biomarkers in the Treatment of Alcohol Use Disorders, 2012 Revision
- eCFR: 49 CFR Part 40, Procedures for Transportation Workplace Drug and Alcohol Testing Programs
- NIAAA: Alcohol Alert No. 72, Alcohol Metabolism: An Update
This article is general information only and is not legal or medical advice.