ETG (Ethyl Glucuronide) urine testing is widely used to detect recent alcohol exposure. If you face testing for work, probation, or health programs, this guide explains how ETG tests work, what affects results, how to prepare ethically and safely, and how to interpret outcomes.
What an ETG Test Measures
ETG is a direct metabolite formed when the body processes ethanol. It is detected in urine as nanograms per milliliter (ng/mL). ETG testing looks for presence and concentration — not intoxication — and can detect alcohol exposure long after blood alcohol concentration (BAC) returns to zero.
Common ETG Cutoffs Explained
| Cutoff | Typical use | Interpretation |
|---|---|---|
| 100 ng/mL | Highly sensitive monitoring (recovery programs, some clinics) | Detects small/exposure-level traces; longer window |
| 200–300 ng/mL | Moderate sensitivity (some workplace programs) | Balanced sensitivity vs false positives |
| 500 ng/mL | Standard/probation screening | Less sensitive; indicates more recent/heavier use |
Factors Affecting ETG Detection Time
- Amount & pattern of drinking: More alcohol = higher ETG and longer detection.
- Time since last drink: ETG declines with time; hours matter.
- Individual biology: body weight, metabolic rate, liver function.
- Hydration & urine concentration: dilution affects measured concentration (labs check creatinine).
- Medications and exposures: some products contain alcohol traces — labs and programs consider context.
What to Do Before an ETG Test (Safe & Ethical)
- Don’t attempt to cheat or adulterate samples. Tests often include validity checks (creatinine, specific gravity) and tampering attempts are detectable and can have legal consequences.
- Stop drinking immediately. The only reliable way to reduce ETG is time and abstinence.
- Tell the testing authority about medications and exposures. If you used mouthwash, certain medicines, or had extreme environmental exposure, disclose it — labs and clinicians can interpret results in context.
- Hydrate sensibly. Drinking water is fine for health; do not over-dilute or falsify samples. Labs may flag dilute samples and require re-testing.
- Seek medical help if you have a medical condition. Conditions (e.g., auto-brewery syndrome) or liver disease can alter results and should be medically evaluated.
- Consult legal counsel if you’re on probation. If a test may have legal consequences, ask your lawyer or probation officer about proper disclosure and next steps.
How to Interpret ETG Test Results
Typical interpretation ranges:
- Negative: below lab cutoff; not detected.
- Low positive: above cutoff but low concentration — may indicate light/older exposure or environmental contact.
- High positive: higher concentrations consistent with recent or heavy drinking.
Only a lab report with numerical values and a qualified clinician or testing authority can provide definitive interpretation relevant to your program or case.
When to Seek Medical or Legal Help
If you test positive and believe the result is incorrect, contact a healthcare provider and, if needed, a lawyer. A confirmatory lab (GC-MS or LC-MS/MS) can quantify ETG precisely; policies vary whether confirmatory testing is available or required.
ETG Decline Chart Example
Below is an illustrative decline curve you can embed on your page to show typical ETG reduction after a heavy drinking session.
Useful ETG Tools & Internal Links
Final Notes on ETG Testing
ETG tests are powerful tools for monitoring recent alcohol exposure. The safest, most responsible approach is to be transparent with testing authorities, stop drinking if required, and seek medical or legal counsel when appropriate. Use calculators and charts for education — not as legal proof.