Understanding nail and body hair drug testing
Any drug that is consumed circulates in the bloodstream and a proportion of it and its metabolites become incorporated into the keratin that make up nails and hair. This tough, fibrous protein traps any drugs and their biomarkers ready for detection. Therefore, both hair and nail testing can detect the same drugs. In addition, the turnaround times for both testing methods are similar.
Nail drug testing
Nail analysis can provide detailed information about drug consumption and is a highly stable, simple-to-collect and easy-to-transport sample.
The clippings need to be taken as near to the nail bed as possible. Approximately 10 mg of nail is required for the test. If the nail is long (5 mm or above) then only one would be required. If the nails are short then it may be best to take clippings from several nails. Toe nails as well as finger nails can be used, but not a mixture of both. The advantages of using toe nails is that there is less potential for environmental exposure.
Acrylic nails, Shellac and other forms of nail varnish would need to be removed as this may damage the surface of the nail and impact on the drug results.
Nail drug testing can provide up to a 12-month overview and is useful when hair drug testing is not available.
Body hair drug testing
Hair is also a strong, stable matrix that can be easily collected and transported. Drugs remain relatively stable in hair and can thus be stored indefinitely. Head hair strand testing is preferred as this can effectively confirm long-term exposure to drugs over a defined period depending on the length of hair collected. This is because head hair grows at a rate of 1 cm a month.
If head hair is not available alternative collection sites on the body could be considered including chest, back, arm, underarm and leg hair. The growth rate of hair from these alternate sites differs from head hair and as such cannot be used to determine a specific timeframe of drug use (up to 12-month overview). Beard hair grows at a rate of 0.7 cm a month, so analysis of this type of hair can provide a more specific timeframe.
Hair strand samples are normally collected by a trained sample collector. Different types of body hair cannot be combined in one sample. Approximately 20–30 mg of sample needs to be collected.
Each body hair sample is chemically washed three times to remove or reduce any drug present prior to analysis. This is to avoid any false positive results from direct transfer (such as by hands), or due to your client being in an environment heavily laden with smoke.
What drugs can be detected?
Both body hair and nail clippings can be used to test for the following drugs:
- Ecstasy (MDMA)
- Phencyclidine (PCP)
Body hair can also detect Buprenorphine and Mephedrone. We can also test for non-standard drugs such as steroids and spice.