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Hair Testing Finds the Root Cause

Avi Lasarow, Managing Director of Trimega Laboratories, sets out the principles and uses of hair testing in family proceedings

image of avi lasarow trimega labs

Avi Lasarow, managing director of London-based Trimega Laboratories

Hundreds of thousands of hair tests are performed every year throughout the world by a small number of forensic toxicology laboratories to identify drug and alcohol misuse. Although this is a field not without its controversy, hair test results are now widely accepted in criminal and civil courts.

In the UK the majority of hair tests are performed in support of divorce and child custody litigation and so are typically requested by social services, family law specialists and by the courts themselves. Elsewhere, other common applications include those to do with employment, professional sports and medical screening.

Not long after the technology was developed to a sufficiently high standard and low enough cost, the UK’s Public Law Outline reforms identified that children placed in temporary care for long periods are considerably more likely to end up in prison, on drugs and/or pregnant. The reforms recommended that cases involving child custody are fast-tracked, putting heavy emphasis on the need for rapid assessment of parental alcohol & drug abuse. Hair tests were immediately identified as an ideal solution to the problem and have since been described by the UK Office of Science & Technology as the Gold Standard for diagnosing dependency (UK Office of Science and Technology Post Note Number 228).

Statistics on the total number of hair tests on parents that are requested are not published but we estimate the figures to be between 5-6,000 a year for alcohol and slighter more for drugs, with around one-in-three testing positive to substance abuse.

Replacing Blood & Urine
The conventional approach to alcohol and drug testing involves taking blood or urine and submitting these liquid samples for forensic tests. However, even when accurate, these traditional tests only relate to recent consumption: approximately 24 hours in blood and approximately three to five days in urine. This short-term window of detection puts children at risk in relation to parental care, public safety at risk in relation to workplace testing and patients at risk from themselves if being treated for alcoholism. Furthermore addicts are more often than not in denial, embarrassed or simply lie when asked to self-report their substance abuse (we find, for example, that over half of heavy drinkers underestimate their consumption of alcohol). As such, it has long been acknowledged by the medical profession that a reliable test to detect alcohol and drug consumption is required and hair is fast-becoming their preferred method.

Whilst hair testing is not intended to replace ‘under the influence’ impairment type tests taken at the time of a particular incident, its real value is in differentiating between social and excessive drinkers - or recreational and habitual drug users. Samples can be collected non-invasively and will provide an accurate record of any alcohol or drugs dependency over a three to 12 month period. From a practical point of view, hair is much easier to handle in the ‘chain of custody’ than blood or urine as it does not need to be stored under any special conditions. It also avoids the embarrassment of chaperones ‘observing’ urine collection. Plus, if a urine sample is in any doubt, it is always possible to take a fresh, identical hair sample and eliminate any false positives or false negatives. A significant breakthrough came earlier this year when Trimega Laboratories combined the two most common types of tests - known as FAEE (fatty acid ethyl esters) and EtG (ethyl glucuronide) - to provide ‘Gold Standard’ results for any case requiring unequivocal evidence. The same sample collection methods are used for both tests and so the combined test costs less than having two tests conducted in isolation.

How It Works
Since hair growth is fed by the bloodstream, the ingestion of drugs or excess alcohol in the blood is revealed by analysing chemical markers absorbed by the hair. As the hair grows, it absorbs these markers into its structure, which remain in the hair. These markers are only produced when there is alcohol or drugs in the bloodstream. The more markers there are, the more has been consumed. A tuft of hair about the diameter of a pencil is required and the industry standard is to test a length of 1.5 inches, which provides a 90 day history. If no head hair is available, body hair can be used instead. Samples must be taken by a trained collector (usually a visiting nurse) on behalf of clients. Results are generally available in seven to 10 working days from receipt of the sample and can be provided in a standard expert witness legal statement. This is accepted, if required, by all UK courts - although in some cases it may be necessary to also provide ‘expert witness evidence’ to support the results.

image of hair folicle structure

Cut-Off Levels
Guidelines from the World Health Organisation are that excessive alcohol drinking corresponds to consumption higher than 60 grams of pure ethanol per day over several months. In the UK, alcohol is based on units to allow drinkers to establish their alcohol consumption. One unit is 8 grams of pure alcohol. However, the amount of drink that equates to 60 grams depends on how strong the drink is. On average, one small pub measure of wine, one half of average strength beer, and one measure of spirit are all one unit. So seven of these units provides 7 x 8 = 56 grams of alcohol. A 750ml bottle of wine with 13% alcohol by volume would contain 9.75 units.

Case Study
Merseyside law firm, Burd Ward Solicitors, has used hair alcohol tests in a successful bid to reunite children with their parents. In early January, hair samples were collected from both parents who had admitted excessive use of alcohol. Both adults reported abstinence in the four day period prior to hair samples being collected, but it was too short a timeframe for the hair alcohol test to yield a negative result. Further testing one month later did however give a negative result, showing that the donors had significantly reduced their alcohol intake. A third and final hair alcohol test carried out one month after that yielded a negative result of less than 4ng/mg, which is typical of teetotallers. This clearly showed that the parents had abstained from drinking in the three month period covered by all three tests.

UK Substance Abuse
In the biggest study of its kind, Trimega Laboratories has released the findings from over 1,500 hair alcohol tests and nearly 2,000 hair drug tests conducted throughout the UK over the past twelve months. It shows there has been a significant increase in the percentage of parents testing positive to drugs when required to undergo a hair test in child custody cases. In the worst affected parts of the UK - London and the South West - around half of hair samples tested showed signs of drug abuse with a year-on-year rise of 13%. Cocaine is most commonly found drug with an average of one in five samples (20%) testing positive, rising to 25.5% in London. Its growing popularity means Cannabis is now the second drug of choice, which was found in an average of 16.5% of samples tested nationwide, led by the West Midlands which recorded 22.5%.

image of Trimage surevey results on drug and alcohol testing

About Trimega Laboratories
Established in London in 2005, Trimega Laboratories has developed a range of innovative techniques for testing substances of abuse. Its core business over the past three years has been laboratory-based analysis of hair samples which, together with its blood results and the largest commercial database of self donor drinking information, has become the basis of underpinning results in court.

For more information on our CPD courses or for copies of a 24-page guide entitled ‘Substance Misuse Testing’, contact Trimega Laboratories on 0845 388 0124 / www.trimegalabs.com.