EtG Hair Follicle Test: The Need To Know
14 November, 2023
The Ethyl Glucuronide or EtG hair follicle test is a type of assessment that detects substances in the hair sample. EtG tests monitor the metabolite of alcohol that remains in the hair for an extended period. Accordingly, the procedure of hair testing is simple. One needs to provide a sample of hair and forward it to a laboratory for EtG analysis. External exposure, the hair sample, and hair products are some crucial factors that may affect the result.
Alcohol testing has become increasingly common in various settings. This includes forensic purposes, legal proceedings, medico-legal purposes, and other pertinent factors. While urine tests and blood tests are common, hair tests offer a unique advantage in terms of their ability to detect substances for up to 90 days. As a result, it is an accurate and reliable method. This article will present the hair analysis, its procedure, and the factors that may affect EtG test results.
What is an EtG Hair Follicle Test
An EtG hair follicle test is a method of substance testing that examines the head hair of a person. It checks for the presence of EtG, a metabolite of ethanol that is produced by the body after the consumption of alcohol. Hence, a hair follicle alcohol test is beneficial in monitoring alcohol metabolites over a period of months.
The testing is typically valuable in situations where there is a need to determine whether someone has excessive drinking over an approximate time period. It can be particularly useful in cases where a person claims that they have been doing alcohol abstinence, but there is suspicion about drinking patterns. Suitably, it is common for testing programs, monitoring, and even in family court cases.
While EtG testing using hair samples can be effective, there are some limitations to consider. The test is unable to provide a precise period of time of when the alcohol was consumed. It can only provide a general timeframe of up to three months. Additionally, the EtG in head hair cannot detect illicit drugs or substances. Its sole purpose is to determine excessive alcohol consumption.
Advantages of the Test Over Other Methods
- Detection period – unlike other tests, this method can provide a timeframe for excessive consumption of liquor that goes back up to 90 days. This longer detection window allows for a more comprehensive understanding of drinking habits.
- Accuracy – the presence of EtG in the hair serves as a reliable marker for excessive alcohol intake.
- Non-invasive – collecting a hair sample is a simple and painless procedure that can be done quickly.
- Objective evidence – it is highly valuable in legal matters, workplace-related cases, or crucial monitoring.
The Procedure of an EtG Hair Follicle Test
The procedure of an EtG hair follicle test involves several steps to ensure accuracy. To begin the test, the candidate needs to provide a small sample of hair. Typically, the hair is from the back of the head, close to the scalp. This area of the hair represents the most recent hair growth. The length of the hair is usually 1.5 inches, providing a timeline of alcohol usage over the past 90 days.
Once there is a hair sample, it undergoes laboratory testing. The laboratory employs techniques to extract and analyse the hair follicle for the presence of EtG. In the lab, the hair sample undergoes a thorough washing process to remove any external contaminants. This ensures that the results focus on the presence of EtG and not on external factors.
Consequently, the specimen is subjected to an initial screening known as immunoassay. This step helps determine which samples need further confirmation using more sensitive testing methods. If the immunoassay produces positive results, the hair sample undergoes confirmatory testing. This assessment may be Gas Chromatography-Mass Spectrometry (GC-MS) or Liquid Chromatography-Tandem Mass Spectrometry (LC-MS-MS).
Interpretation of the Results
Interpreting the results of the test requires understanding the meaning behind reported findings. A negative result means that no traces of EtG is present in the hair sample. This suggests that the individual has not consumed alcohol within the detection window. Meanwhile, a positive result indicates the presence of EtG. As such, the person has alcohol markers during the detection window.
EtG hair tests often have cut-off levels. Different organisations or agencies may have different cut-off levels, depending on specific requirements. It is essential to consider these limits when interpreting the results. This is to determine if an individual exceeds the threshold.
Factors that May Affect the EtG Hair Follicle Test Result
The accuracy of an EtG hair follicle test can be influenced by several factors. Firstly, the exposure to alcohol in the environment, such as in bars, clubs, or gatherings. This exposure can potentially contaminate the hair and cause false-positive results. Secondly, hair treatments or cosmetic treatments, such as dyes, shampoos, and bleaching agents, can interfere with the results.
According to studies, hair colour can also impact the results. Dark-coloured hair tends to retain more EtG than lighter hair. Another consideration is the length of the hair sample. Typically, hair grows at a rate of approximately half an inch per month. Therefore, a longer hair sample allows for a longer detection window. If the hair sample is too short, it may limit the accuracy and reliability of the results.
Different laboratories may employ different testing methodologies, which may differ in accuracy and sensitivity. It is essential to ensure that the laboratory conducting the test follows protocols and procedures for hair analysis. Also, the metabolism and hair characteristics of a person can impact or influence the result of hair testing.
Is there a Possibility for a False Positive
The method of testing is a common method for detecting alcohol consumption over an extended period. While it is highly accurate, false positives can occur. Factors such as environmental exposure to alcohol, the use of certain hair products or treatments, and even certain medical conditions can potentially lead to inaccurate results.
Additionally, the improper handling, length, and dark colour of the hair sample can contribute to a false positive result. Also, the chosen laboratory holds crucial value in determining accurate results. It is important to note that if a false positive does occur, further confirmatory testing can be done to verify the results.
The EtG hair follicle test is a highly accurate method for detecting alcohol consumption over a longer period of time. This test measures the presence of EtG, a metabolite of alcohol, in the hair follicles. Unlike other types of tests, the method can monitor alcohol use up to 90 days after consumption. It makes it an effective tool for monitoring long-term alcohol abstinence or identifying chronic alcohol intake.
The procedure of the test is simple, as long as there is a reliable laboratory. A person will just need a hair sample, and the professionals in the laboratory will do the analysis. In the lab, the hair sample undergoes initial screening and further confirmatory testing if it holds a positive result. Nevertheless, it is crucial to know the factors that can influence the result. This can include external exposure, hair products, the hair length sample, and testing methodologies.