Court-ready hair alcohol testing

A hair follicle alcohol test is the test described on this page — the same appointment, the same certificate. It is the name most people search for, and you are in the right place.

Two other names attach to it. The laboratory analyses the hair shaft, the strand itself, rather than the follicle — the living root beneath the skin. And what it measures is ethyl glucuronide, or EtG, which the body produces only when it processes alcohol. Neither name changes what you book or what you receive.

Because it is produced only when the liver metabolises ethanol, EtG separates actual consumption from external contact with alcohol far more reliably than the alternatives.

That cuts both ways, which is the point — it is as useful for clearing someone wrongly accused of heavy drinking as for establishing that the drinking occurred.

Fatty acid ethyl esters (FAEEs) are not included. The Society of Hair Testing — the international body that sets these standards — dropped them from its Consensus on Alcohol Markers in the 2019 revision, for lack of uniformity in how FAEE results were analysed and interpreted.

Hair treatments. EtG is water-soluble and more vulnerable than most analytes to harsh chemical treatment. Laboratory tests on hair samples show some loss after aggressive relaxers or thermal straightening — but there are no controlled studies in living people showing it reliably drops a result below threshold, and attempting it risks both the hair and the credibility of the sample.

Alcohol-containing hair products. Not a factor. EtG is formed in the liver, so topical ethanol does not produce it.

Liver disease. Can in principle affect how ethanol is metabolised, and is one of the factors a forensic interpretation would consider.

Sample length. International guidelines recommend a minimum of 3 cm, which is what puts an EtG interpretation on firm footing. If your hair is shorter than that, call us before booking and we will talk through the options.

A shorter sample can produce a laboratory result. What it does not have is a yardstick: there are no equivalent internationally recognised EtG reference thresholds for samples shorter than 3 cm, so a figure from one cannot be read against the bands above.

At least 3 cm — roughly three months of growth — is what lets a result be considered against the recognised international guidelines, which is what makes it worth having in front of a court. If a court or agency has asked for a shorter period, tell us before you book and we will talk through what the laboratory can report.

Routine work for us — child welfare assessments, custody disputes, employment matters and criminal proceedings. Every case is handled with the same confidentiality, whichever party arranged it.