Hair Follicle Test – What Is It and What Can It Detect?
07 November, 2023
A hair follicle test is a type of drug test that is used to detect the presence of drugs or alcohol in the hair of a person. The test works by looking for traces of drug molecules in the hair strands that have been exposed for a certain timeframe. In addition, it can detect a wide range of substances, commonly illegal drugs, prescription medications, and alcohol. This method is helpful for employers and healthcare institutions.
Drug testing has become increasingly common in various industries and organisations. It helps determine if a person abuses substances, which can compromise workplace safety. Additionally, regular testing helps deter illicit substance use and prevent accidents. A hair drug test is one of the methods that can detect drug usage. In this article, we will provide an overview of what a hair test is, what it can detect, and other related factors.
What is a Hair Follicle Test
A hair follicle test is a method of drug and alcohol detection through hair analysis. It uses a small sample of hair to determine past consumption of drugs and alcohol. This type of test is suitable in situations to see if a person has substance abuse problems. It can help healthcare professionals in diagnosing potential health risks and developing an appropriate treatment method.
Hair testing is a non-invasive method as it requires no blood or urine sample. The test is usually painless, and the sample can be taken from any part of the body, particularly head hair. It is also relatively resistant to tampering and cannot be manipulated by adulterating the sample.
Hair testing kits are available for personal or professional use. However, it necessitates sending it to a laboratory for analysis. The process also takes longer than standard saliva and urine screening. Thus, it can be more expensive than other types of drug testing. Due to these limitations, it is often used after an accident, pre-employment, and other legal cases.
Sample Collection Procedure
- Collecting hair samples does not require preparations on the part of the individual.
- The collection procedure involves cutting a small amount of hair at the back of the head, close to the scalp.
- The standard sample is approximately 100 mg of 1.5 inches of hair. This is around 100 to 200 strands of hair.
- Body hair can be a substitute if head hair is not available.
- Store the collected sample in a storage container and seal it to maintain its integrity during transportation to the testing facility.
- Label the root ends properly with an arrow or other identifiable marker.
What Substances a Hair Follicle Test Can Detect
A hair follicle test can detect a wide range of substances. Firstly, it looks for common drugs of abuse, such as cocaine, marijuana, opiates, amphetamines, and phencyclidine (PCP). These substances have highly addictive properties and can cause significant health issues. Secondly, it can also trace prescription drugs and determine potential abuse.
Additionally, hair specimens can identify significant alcohol use. Alcohol is a volatile compound that readily absorbs into various body parts. The metabolites of ethanol, such as ethyl glucuronide (EtG) and ethyl sulphate (EtS), are also detectable in urine and saliva. However, they stay the longest in hair. This makes the hair strand drug test difficult to manipulate or cheat.
After a person consumes drugs or alcohol, the body breaks them down into byproducts. These drug metabolites enter the bloodstream into different organs, including the hair follicles. They deposit in the hair shaft and remain there as the hair grows. Thus, it can provide a comprehensive picture of the substance use history or periods of alcohol abstinence of a person.
Accuracy and Detection Window
The hair strand drug test provides one of the most accurate and reliable detection methods. Once the metabolite is deposited in the hair shaft core, it cannot be externally washed or flushed out. Moreover, the test uses the Enzyme-Linked Immunosorbent Assay (ELISA) method. This advanced procedure eliminates any chances of external contamination.
The window of detection of hair is 90 days. This means it can trace substances for several months from the date of last use. However, it is determined by the half-life of the drug or the time it takes for the body to eliminate half of the substance from the bloodstream.
Interpretation of Results from a Hair Follicle Test
The results from a hair follicle test can provide valuable information about the drug and alcohol use history of a person. However, it requires a careful interpretation of results to reach a conclusion. A qualified medical professional can determine the implications of the tests. Generally, the test is positive if it reaches the cut-off level for each drug type.
The cut-off levels determine the concentration of endogenous metabolites in the hair samples. However, different laboratories may have different cut-off levels. Setting a threshold is vital to avoid false positives due to minimal exposure. Thus, it is crucial to understand the specific guidelines for the test. Moreover, it can detect a drug within a timeframe but not the exact period.
A positive test result means a person has ingested the substance within the detection window. However, it does not signify the individual is currently impaired. Furthermore, it can help determine if a person has drug and alcohol abuse problems. A healthcare provider can look for patterns that can be useful for treatment.
Factors that Can Affect the Results
Several factors can come into play and affect the results of hair drug testing. Firstly, hair growth varies with each person. This may affect the detection time of an illicit drug. Secondly, genetic variables can have an impact on the test, such as the type of hair.
Additionally, extreme treatments or the use of strong products can alter the hair matrix. This may interfere with the results of the test or render the test invalid. Thus, testing officers may use hair samples from other body parts. Likewise, a combination of test methods can help ensure the accuracy of the results.
A hair follicle test is one of the most reliable and accurate testing methods for drugs and alcohol. It can provide a comprehensive picture of substance use history over the last 90 days. This test works by detecting metabolites present in the hair shaft. Furthermore, it involves the cutting of a few strands of hair from the back of the hair. Then, the samples are sent to a laboratory for analysis.
Different laboratories may have different cut-off levels. Therefore, it is advisable to refer to a medical professional for an accurate interpretation of the test results. It is also important to be aware of the factors that can affect the test. It includes hair growth, genetic variables, and extreme treatments. Nevertheless, hair analysis can help identify if a person has substance abuse problems. This enables employers or healthcare providers to offer the necessary intervention or treatment.