Hair Follicle Drug Tests on the Rise

Hair follicle drug tests are growing in popularity for two main reasons – the inability to cheat the test and the longer term detection window provided by such a test. In addition to standard hair follicle tests, some labs are also now offering environmental exposure testing using hair samples.

1. Inability to cheat the test

Hair follicle tests involve a directly observed hair collection by a trained specimen collector. Unlike urine specimen testing, where a donor is behind closed doors, this specimen collection process cannot be subverted or hidden in any manner. A quick “clean up” fix like those offered online are great money makers for those selling the products, but they have no effect on hair follicle testing results. The excuse that you were exposed to drug smoke does not hold any water either as a standard hair follicle test involves special processes to clean the hair prior to testing and the matter being tested is the inside of the hair itself.   If an environmental exposure test is ordered, the test result will clearly identify the positive reading as exposure and not use. More on exposure testing later in this article.

2. Longer detection window

Unlike urine testing which detects usage for the past 2-7 days (longer for marijuana users), hair testing typically provides a window of detection for 90 days or more. When drugs are taken, the metabolites go into the hair follicle, and then into the strands themselves, where they stay, pretty much forever. Hair on your head typically grows at a rate of approximately .5 inches per month. In this case, if your hair was 18 inches long, and you tested the entire length of hair, they could find drugs consumed more than 3 years ago! There is no reason to worry about this in most cases, because the standard hair follicle test only tests 1.5 inches from the root end of the hair strands.

If head hair is not available to collect, body hair may be collected. Body hair collection can be done from facial hair, arms, legs, chest or underarms. The detection window for body hair is estimated by some labs to be up to one year, but this has yet to be scientifically verified. A good rule of thumb, regardless of where the hair was collected from is that the detection window will reflect the past 90 days of use. There is no way to determine from test results when the drug use occurred, only that drug use did occur.

3. Types of Tests

The two primary types of hair follicle tests include standard hair testing and exposure testing.

For standard hair follicle tests, the number of drugs being tested for can be any number of combinations from 5 panel, 10 panel, 17 panel or more. Tests can also determine alcohol usage as well as drug usage. This type of testing only determines consumption/use of the substance being tested for.

For exposure tests, also known as environmental exposure tests, the hair strands are not washed prior to testing and the outer shell of the hair is tested for the presence of drugs. Exposure testing is most commonly combined with hair follicle testing which tests for exposure to drugs as well as ingestion of drugs. If exposure to drugs is detected, the test results will clearly indicate that the specimen tested positive for exposure to drugs.   Exposure to drugs does not indicate ingestion or use of drugs. It simply indicates that the person was in the presence of drug use. This is a popular test in child welfare situations and is used to determine if a child has been exposed to drug use in addition to the possibility of ingesting drugs. This test, offered by Carolina Testing is known as the Child Guard Test.

In closing, hair follicle testing offers a fool proof way to test for a wide range of testing possibilities over an extended period of time. Depending on your exact needs, the costs of hair follicle testing can typically range from $120 to over $500. Please contact your Carolina Testing professionals for assistance in choosing the right test for your needs.