Legal Hair Alcohol Test
Ensuring the most accurate test
With alcohol abuse costing the UK over £23 billion per year and being a significant factor in over 1/3 of domestic violence cases, as well as more than 63% of care proceedings, it is essential that alcohol testing is carried out in a way that accurately and truthfully supports your clients.
Around 15 – 20% of hair alcohol testing is incorrectly ordered or reported, which means that alcohol consumption can be falsely assessed as excessive, which may not be the case. Incorrect reporting of alcohol testing – with no consideration of other factors through toxicological analysis – can therefore lead to court delays, overages, and miscarriage of justice.
DNA Legal advise that the outcomes of these tests can lose your client a custody case, not to mention wasted costs and the miscarriage of justice.
Three critical alcohol testing points
- The primary hair strand testing marker for alcohol, Ethyl glucuronide (EtG), should be supported with Fatty Acid Ethyl Ester (FAEE) testing if chemical treatment of the hair is evident. This permits mutual exclusion of false positives or negatives.
- FAEE testing should never be used in isolation, due to the potential for contamination by innocuous hair and body products.
- Hair strand alcohol testing is best used to complement blood testing (CDT, LFT, FBC, PEth).
Hair Alcohol Testing Explained
Hair strand alcohol testing assesses EtG and FAEEs biomarkers.
These biomarkers are incorporated in the hair through deposition via blood vessels or via sebum secreted from the sebaceous glands. Unlike drug testing, due to the degree of metabolite migration in the hair it is only possible to perform segmentation in an EtG test to two 3-month periods. Hair tested for FAEE cannot be segmented at all.
The alcohol markers (EtG and FAEE) are absorbed into the hair via sweat and diffusion. Unlike drug testing where the metabolites are absorbed through the root of the hair, when a client consumes alcohol the entire length of the hair will be contaminated with alcohol. Therefore it is not possible to segment the hair.
Free Case Review
It is estimated that 15-20% of testing is ordered or reported incorrectly – meaning thousands of clients may have been affected by an erroneous overestimation of alcohol consumption.
If a previous case has involved results that you or your client are adamant do not correlate with your expectations, we will provide free-of-charge consultation and a case review to determine whether important factors have been overlooked.
Hair Products & Chemical Treatments
Hair alcohol testing must be interpreted with caution. This is especially true for clients who use chemical treatments.
Recent studies have shown that around 30% of hair strand alcohol testing produces contradictory results (negative EtG and positive FAEEs) attributable to alcohol-containing hair products causing false positives. At DNA Legal, we assess all underlying factors when interpreting these results.
Alcohol Test Detection Periods
Hair strand alcohol testing can assess consumption over a period of 6 months – as opposed to the one month maximum assessed by alcohol blood tests, or the approximate 4-day detection window provided by urine.
DNA Legal recommend combining hair strand and blood testing to provide the most accurate assessment of consumption over a proximal, and extended period. Our testing can distinguish between abstinence, regular ‘social drinking’ and excessive alcohol consumption. We are one of the only toxicology testing providers who can ascertain total abstinence through PEth testing.
Through analysis of hair samples, the testable time period for assessing alcohol consumption is either 3 or 6 months – depending on the length of the donor’s hair.
The hair is collected from the vertex region of the scalp, in accordance with standard methodology. Approximately 100 hairs per sample are collected.
As an alternative sample, body hair can also be used to assess alcohol consumption. However, important consideration must be made of the differences in physiology, development rates and growth patterns.
Hair Alcohol Testing Facts
- Hair strand alcohol testing allows assessment of up to 6 months of consumption – compared with approximately 80 hours in a urine test, or one month in blood testing
- FAEEs are additional alcohol biomarkers that can be assessed alongside EtG to permit mutual exclusion of false positive/negatives. It is recommended to perform both tests. Like EtG testing, FAEE testing permits assessment of varying degrees of consumption.