How High May the EtG Level Be?

Alongside FAEE, EtG is one of the most important alcohol markers for reliably detecting previous alcohol consumption. Most is excreted in urine within hours to days, but a small proportion becomes permanently incorporated into hair.

This incorporation makes EtG particularly informative for MPU assessments. But how high may the EtG level be, and what do different measurements mean? This guide explains how EtG forms, how it enters hair, how soon it becomes detectable and which thresholds apply.

Key points

• EtG reliably indicates previous alcohol consumption: briefly in urine and over the longer term in hair.
• Values up to 5 pg/mg are considered indicative of abstinence.
• Values between 5 and 30 pg/mg suggest moderate consumption.
• Values above 30 pg/mg indicate significantly increased drinking.
• Hair analysis is reliable only on untreated hair.

How high may the EtG level be?

The EtG level must be no higher than 5 pg/mg to count as proof of abstinence. Values between 5 and 30 pg/mg suggest moderate consumption; anything above this indicates excessive alcohol consumption.

EtG as an alcohol marker and its significance

EtG is considered one of the two main markers of previous alcohol consumption. It forms when the body breaks down alcohol. Most EtG is quickly excreted in urine, enabling short-term testing. A smaller proportion reaches the hair roots and becomes incorporated into the hair structure, remaining detectable for months.

Even completely abstinent people rarely have entirely EtG-free hair because minor environmental influences can cause minimal exposure. Established thresholds therefore allow clear classification and form the basis of proof of abstinence for an MPU.

How high may the EtG level be?

The EtG level provides important information about the drinking behaviour of the person tested. A value up to 5 pg/mg is considered unremarkable and corresponds to the international abstinence standard. Values between 5 and 30 pg/mg indicate occasional or moderate consumption.

A value above 30 pg/mg suggests significantly increased, problematic drinking. Because even minor environmental influences can cause small EtG traces, the threshold is deliberately not zero. Results should therefore be interpreted in relation to hair length, haircare habits and history.

Table: interpreting EtG levels in hair

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How quickly does EtG become incorporated into hair?

EtG incorporation depends strongly on the amount and frequency of consumption. EtG is often detectable in urine within hours, but takes longer in hair. Initial measurable incorporation is generally present after about three days. This delay occurs because EtG must first enter the bloodstream before being transported to the hair roots.

Because even abstinent people cannot avoid minimal environmental exposure, completely EtG-free hair is rare. In people who resume drinking after abstinence, consumption can be clearly identified in newer hair sections. Changes in drinking behaviour over several months can therefore also become visible.

How does EtG enter hair?

EtG forms as a breakdown product when the body processes alcohol. Most leaves the body in urine, while a smaller amount travels through the blood to the hair roots. There, it becomes incorporated into the developing hair structure and remains stored over the long term. Each millimetre of growth thus creates a kind of consumption timeline.

However, some EtG washes out over the months because it is water-soluble. Haircare plays an important role. Frequent washing can reduce the level somewhat, but cannot make EtG disappear completely. Experts therefore point out that hair analysis is reliable only on untreated hair.

How informative is hair analysis?

Hair analysis is considered a particularly reliable method for assessing long-term alcohol consumption. It not only indicates consumption but also allows conclusions about patterns and changes in drinking behaviour. Older and newer hair growth can be clearly distinguished.

There are limitations, however. Chemical treatments such as dyeing, tinting or bleaching can distort measurements. Very intensive haircare can also slightly reduce EtG levels. Hair analysis is therefore performed only on untreated, natural hair. Nevertheless, it remains one of the most important tools for proof of abstinence and MPU assessments.

Can the EtG level be influenced?

It is difficult to actively change EtG levels. Drinking plenty of water may accelerate urinary EtG excretion but does not affect incorporation into hair. Intensive washing is also often assumed to significantly lower the level. In reality, it can wash out a small proportion of EtG, but most remains firmly bound in the hair.

Dyeing, bleaching or tinting can cause greater changes, which is why such treatments are excluded before hair analysis. Consistent abstinence throughout the entire monitoring period is therefore the only way to provide genuine proof of abstinence.

Conclusion

EtG is a highly sensitive marker that reliably reveals alcohol consumption over months. Hair analysis in particular provides precise information about drinking behaviour and periods of abstinence. Anyone hoping to pass an MPU should understand the applicable thresholds and that EtG levels are practically impossible to manipulate.

Only genuine abstinence leads to values below 5 pg/mg. For those seeking certainty, hair analysis offers a powerful tool and clear guidance for a fresh start.

Sources:

• Labor Enders: Hair Analysis Thresholds and Interpretation
• Health Portal: Ethyl Glucuronide in Urine – Reference Values and Significance
• Swiss Society of Legal Medicine: Determining Ethyl Glucuronide (EtG) in Hair Samples (PDF)

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FAQ

What is the threshold for EtG in urine?

The common urine EtG cut-off is 100 ng/mL (nanograms per millilitre). Values below this threshold are considered negative, providing evidence of short-term abstinence.

Which hair EtG value demonstrates abstinence?

To demonstrate alcohol abstinence through hair analysis, EtG must be below 5 pg/mg (picograms per milligram). This threshold is established internationally by the Society of Hair Testing (SoHT).

At what level is someone considered a regular drinker?

A hair EtG level between 5 and 30 pg/mg suggests moderate to social alcohol consumption. Values above 30 pg/mg are interpreted as indicating regular or excessive consumption.

Can alcohol-free beer increase EtG levels?

Yes. Because “alcohol-free” beer may legally contain up to 0.5% alcohol, consuming larger quantities can measurably increase EtG levels. It should therefore also be avoided during an abstinence programme.

How long can a single episode of intoxication be detected?

EtG is detectable in urine for up to 72 hours, or three days, after a single episode of consumption. In hair, EtG grows into the structure and remains detectable for months depending on hair length, provided consumption was sufficient to exceed the 5 pg/mg threshold.

Do medicines affect EtG levels?

Certain medicines containing ethanol as a solvent, such as cough syrups or drops, can significantly raise EtG levels. Inform your laboratory beforehand about every medicine you take.

What does a value of 0 pg/mg mean?

A value of 0 pg/mg is technically difficult to measure because a detection limit always exists. A result of “not detectable”, below the cut-off, is the best possible result. It confirms that no relevant alcohol consumption occurred during the period examined.

Can drinking a lot of water lower the value?

In urine testing, drinking large quantities of water can dilute the concentration. However, the laboratory identifies this as attempted manipulation through dilution by measuring creatinine at the same time. Drinking does not influence the hair value.

Are EtG thresholds the same for men and women?

EtG cut-offs are identical for men and women. Alcohol breakdown and incorporation into hair do not differ physiologically enough to justify different thresholds.

What is the difference between EtG and PEth?

EtG (ethyl glucuronide) is a breakdown product readily detectable in urine and hair, whereas PEth (phosphatidylethanol) is a direct alcohol marker in blood. PEth is particularly suitable for retrospectively assessing drinking behaviour over the previous two to four weeks.