Alcohol hair testing involves testing a section of an individual’s head hair for biological markers (biomarkers) of alcohol consumption. The level of biomarker found in the hair can help determine if a person has been drinking chronically and excessively. Hair alcohol testing is unable to determine exactly when alcohol has been consumed as the results obtained are an overview for the whole approximate time period covered by the hair section analysed. This overview can be for 3 or 6 months, depending on the length of hair analysed.

As head hair grows at an approximate rate of 1 cm each month, the minimum length of hair needed is a 3 cm section to provide a 3-month overview. Sample collectors ensure that the hair strands collected are taken from a discreet section nearest the scalp. Around 200 individual strands are required for each sample, which is about the width of a pencil.

How does alcohol hair testing work?

Hair alcohol testing works by assessing the amount of alcohol biomarker in the hair sample. AlphaBiolabs analyses two markers in its alcohol hair tests: ethyl glucuronide (EtG) and a fatty acid ethyl ester (FAEE) called ethyl palmitate (EtPa). Both of these are specific long-term markers of ethanol and their levels can assist in assessing excessive alcohol use by an individual

As hair grows, EtG and EtPa are absorbed and bound into the hair strand via different routes.  Both markers are analysed because they are affected by external factors in different ways. EtG is produced by the liver and incorporated into the hair, mainly through sweat. It is hydrophilic, meaning that it is water soluble. As such, some EtG may be lost through the use of hair dye, bleach, perm solution and excessive hair washing.

EtPa is produced in the blood and incorporated into hair via sebum (an oily substance secreted by glands in the skin). EtPa is lipophilic and therefore not water soluble, so although not affected by hair washing, the amount detected could be increased by the use of hairsprays, gels and wax if they contain alcohol.

Accurate alcohol hair testing

The accuracy of its alcohol hair testing is assured because AlphaBiolabs is an accredited laboratory that follows the consensus on hair alcohol testing for chronic excessive alcohol consumption published by the Society of Hair Testing (SoHT). The amount of EtG and EtPa recorded will be considered either above or below the recommended SoHT cut-off levels. Because of the respective strengths and weaknesses of EtG and EtPa, both biomarkers are tested and their findings should support each other in order to determine chronic excessive consumption of alcohol. A recent directive from the SoHT allows a positive EtG result to be reported as chronic and excessive consumption of alcohol without the support of a positive EtPa result but it is desirable that the two results concur.

As well as hair alcohol tests, AlphaBiolabs provides breath, blood and nail alcohol testing. We also offer round-the-clock testing via SCRAM Continuous Alcohol Monitoring®. For expert advice or further information, please call 0333 600 1300 or email us at