Is Hair Drug Testing Accurate?

image of how accurate are hair drug tests 1Medical and work experts show the contrary.

Just recently, the Department of Transportation has started to make efforts to get a bill passed regarding the introduction of hair testing instead of urine testing for drug use in drivers. However, there are studies that show that the decision may not render the required results since it is not as accurate as it is popularly known.

According to the new bill, transport carriers can test their operators using hair drug testing, instead of asking for an urine sample to detect the use of drugs, under certain conditions. These include testing for new employees and random situations, but only if the same type of test was used when the operator was hired. Many transport carriers are supporting the bill.

Nonetheless, there are scientific sources that consider hair testing to be inferior in the quality of results to urine testing, because it can provide skewed results depending on certain categories of persons being tested.

What happens in the human body when illegal substances are being used is that interactions happen with the drugs, and certain markers appear in the hair follicles. Nonetheless, this does not happen overnight and there is a time frame within such tests cannot be relevant. This is said by Dr. Kent Peterson, a prominent figure in the medical world, involved in many organizations regarding this type of testing, including the American College of Occupational and Environmental Medicine.

image of should employers hair drug test employeesWhat Dr. Peterson adds is that basically, if someone is tested for drug use, the only thing the test can say is that the person has used (or not) drugs sometime during the last three months, without saying anything about the person’s state under the current circumstances. That is why, hair testing is recommended, at best, when hiring new employees.

Another major issue Dr. Peterson has with this type of testing is that people with low pigmentation in their hair are less likely to show the metabolites that are produced by the interaction with the drugs the body naturally produces. On the other hand, people with darker, curlier and thicker hair are more likely to preserve the presence of these metabolites for longer periods of time. Without a doubt, introducing this type of testing as a common rule may work against certain categories of employees, based on how their hair reacts. Seeing that Dr. Peterson has been involved in educating thousands of experts in drug testing, his words should really weigh in on the matter.

A well known case that also contributes to the controversy was the one regarding a group of officers working for the Boston law enforcement. These officers were laid off after their tests came back positive for cocaine. In regards to the case, the Massachusetts Civil Service Commission spoke about the lack of reliability in the case of hair testing, and about the fact that its results should not be used for putting people out of their jobs, as long as their recent impairment could not be proven.

The above-cited sources are not the only ones against hair testing as a common method to identify drug use. The Substance Abuse and Mental Health Services Administration has not, so far, recommended this method because of its lack of accuracy and reliability.

Among the issues mentioned by this organization regarding the controversy surrounding hair testing, a few should not be overlooked: bias against people with certain hair characteristics, lack of reliable information on how long drug markers remain in someone’s hair, the possibility of external contaminations that cannot be controlled by the people being tested, and the different response triggered by the use of different drugs.

Scholarly studies regarding the exact efficiency and accuracy of hair testing are lacking, which is another sign that this type of drug use verification should not be employed as a common and widespread procedure. Hair testing companies seem to be involved in exercising pressure on the admission of this type of test on a national scale, but no support from scientific groups has been provided so far to verify their claims.

Another prominent figure interested in the accuracy of these tests is Lewis Maltby. In his position as the head of the National Workrights Institute from Princeton, he considers that one of the major issues to be noted is the hair’s sensitivity to external factors. If, for instance, someone has to stay in a room filled with weed smoke, their hair sample may test positive for marijuana consumption, despite them not even smoking at all.

The National Institute on Drug Abuse has been reluctant for years to accept hair testing, as Lewis Maltby also points out. Passing the bill mentioned in the beginning of this article will only be the result of the pressures put by companies directly involved in this matter that want their line of work to become a very productive one in the future.

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