Hair Follicle Test: What It Is and the Procedure

Alcohol and drug testing has become commonplace to help ensure safety and identify those with substance use disorders. A hair follicle test is one of the methods workplaces, law enforcement agencies, and health professionals use. It involves the collection of about 90 to 120 hair strands that are at least 1.5 inches. Afterwards, these samples are taken into a lab for analysis. Then, the report will state the substances tested for and if they were positive or negative.

The misuse of alcohol and drugs is a prevalent issue and results in many consequences. It affects the physical and mental health of the concerned individuals. Moreover, it endangers the community due to the higher risks of accidents. Fortunately, testing is an effective deterrent for misusing substances. In particular, hair follicle screening provides a lengthy detection period helpful for acquiring a substance use history. This article will present the definition, procedures, and detection window of a hair test.

What is a Hair Follicle Test?

A hair follicle test is a method used for detecting drug and alcohol use over a long period of time. This typically involves collecting samples of hair from the individual and analysing them in a laboratory. It is a highly accurate method that detects illicit drug and alcohol misuse. In particular, it is effective for identifying long-term or chronic drug and alcohol abuse.

The results of a hair test can provide information about the substances used, the frequency of usage, and an approximate timeline of use. This is useful for workplace, legal, and medical purposes since it can help monitor the abstinence or lack thereof of the individual. However, it can be more expensive compared to other alcohol and drug testing methods because it requires laboratory analysis.

Nevertheless, this is helpful for pre-employment testing as a requirement for an employment contract. It is also helpful for legal testing for court proceedings. Lastly, it works for monitoring those in substance abuse treatment programs.

Advantages Over the Other Testing Methods

• Hair follicle screening has a significantly lengthier detection window compared to blood, oral fluid, breath, and urine tests.
• The sample collection is non-invasive, making it more comfortable and convenient than other screening methods.
• It can provide information about the alcohol and drug use history of the individual months before the time of collection. It can also help professionals identify patterns of drug use.
• It is difficult to tamper or contaminate the samples, increasing the reliability and accuracy of the results. This is because the collection can be done under supervision without violating the privacy of the person.

Procedure in a Hair Follicle Test

The process of a hair follicle test starts with gathering about 50-100mg or 90-120 hair strands. Typically, collectors will take about 1.5 inches of scalp hair to cover about three months of substance use. However, they may also use body hair samples as an alternative to head hair. This includes beard hair, armpit hair, and leg hair.

Once the collector gathers an adequate amount of hair specimens, these will be brought into a laboratory for analysis. There, the lab technicians will first wash the hair specimen to prepare it. This step removes some external contaminants that may hinder accurate analysis. After washing, they will submerge the hair in a solution to dissolve the outer layer and expose the inner core.

For hair analysis, a common method during hair sample testing is Gas Chromatography-mass Spectrometry (GC-MS). Gas chromatography involves using a gas carrier medium to separate the compounds. Then, mass spectrometry classified the ions based on their mass-to-charge ratio. Accredited laboratories may also opt for liquid chromatography-mass spectrometry (LC-MS), which works similarly to GC-MS but with a liquid mobile phase.

Detectable Substances

Hair testing can trace a wide range of substances. This includes illegal drugs, such as cocaine, marijuana, opiates, and phencyclidine (PCP). It can also detect amphetamines, methamphetamines, opioids, and benzodiazepines. Hence, hair follicle testing is a comprehensive method of tracing substances when using the correct panels.

In addition, there are laboratory methods that they can use to distinguish between actual substance use and contamination from external contaminants. This can help ensure accurate results and prevent false reports. This enables it to be a reliable method for tracing the misuse of prescription medications, illicit drugs, and alcohol.

Window of Detection in Hair Follicle Tests

Generally, the window of detection of hair follicle tests is up to 90 days. The longer period is attributed to the nature of hair growth since the substances and their metabolites become trapped in the hair follicle as it grows. This allows for a more comprehensive and accurate assessment of the history of drug use of the individual.

However, the detection window may vary depending on certain factors. Moreover, it is important to note that body hair may offer a longer detection period because of its slower growth rate. In some cases, it can trace substances for up to 12 months. In addition, hair screening also does not detect the substances consumed about seven days before the time of collection.

Furthermore, several factors can impact the results. Firstly, genetic variables such as hair type can affect the test. Secondly, some cosmetic hair treatments may also damage the hair and render the test invalid. One example of this is bleaching since it can alter the hair matrix. Lastly, environmental factors such as exposure to drugs or secondhand smoke can potentially affect the result.

Factors Affecting the Detection Window

Several factors may affect the detection window of hair strand testing. One of them is the rate of hair growth. This can vary from person to person. Hence, it is also important to ensure that scalp hair and body hair specimens do not get mixed up.

Another factor that can impact the detection window is the length of the hair. Generally, a longer hair strand will enable the tracing of longer periods. This is why it is crucial to get at least 1.5 inches of hair specimen for testing. Lastly, the type of substance consumed may also affect the detection window of a hair screen.

Conclusion

A hair follicle test is a method of testing that various organisations use to detect the misuse of prescription medications, alcohol, and illegal drugs. It helps acquire a history of substance use, which can help prove abstinence for various purposes. It generally has a detection window of 90 days. But this can vary depending on several factors. It can detect a wide range of substances, including cocaine, marijuana, PCP, amphetamines, methamphetamines, opioids, and benzodiazepines.

The procedure starts with the collection of about 90 to 120 strands of scalp hair. Alternatively, they may use body hair like armpit or leg hair if needed. Afterwards, these samples are brought into a lab for analysis. The lab technician will wash the specimens to minimise contaminants that may interfere with the results. Then, they may use specialised techniques, such as GC-MS and LC-MS, to analyse the samples.