Hair follicle tests determine if individuals use illegal substances or performance enhancing medications. These tests prove useful for testing employees, athletes and students. Hair follicle tests can detect substances used for a longer time frame than blood or urine tests. These tests can also analyze nutrient and mineral levels in the body.
Uses
Hair follicle tests can determine the use of illegal substances such as alcohol, nicotine, cocaine, Ecstasy and marijuana in a time frame of months and even up to a year. Athletes can also receive testing for performance enhancing steroids and other drugs. The tests analyze long-term mineral and nutrient deficiencies in the body or if there are toxic minerals present.
Method
A hair sample is usually taken from the top or the back of the head. Body hair can also be used. Samples include hair roots for analysis to determine the genetic identity of the person, in the case of drug testing. The hair follicle sample is then broken down and analyzed in a lab. Molecules of drugs and minerals in the body for the past three to 12 months can still remain in the hair.
Comparison
Drug testing typically uses blood or urine samples. However, these samples can become susceptible to tampering and may not as prove effective as hair follicle tests. The body filters out drugs and other substances and it may not show in the blood by the time blood samples receive testing. Urine samples show evidence of drugs and illegal substances longer than blood tests but this also may not prove an ideal method, as the body soon metabolizes the substances and they will not show up in the urine. According to the Journal of Analytical Toxicology, in hair follicle tests the presence of a drug can be detected for three months or longer and it prove less likely that a hair sample can be replaced or altered.
Disadvantages
According to David L. Watts, Ph.D., Director of Research at Trace Elements Laboratories, as hair grows slowly; it may not accurately reflect current concentrations of drugs or nutrients in the body. For this reason it hair follicle tests prove better for providing data on time and degree of exposure unlike blood and urine samples which give immediate status readings only. A study published in the Journal of the American Medical Association also advised in 2001 that hair mineral and nutrient analysis from many private, mail-in laboratories were unregulated and unreliable.
Legal Uses
Hair follicle tests are used in some legal proceedings along with blood and urine tests because they can provide evidence and amounts of substances used in a longer time frame. Other legal uses for hair follicles include paternity testing and genetic identification.
References
- Trace Elements: Hair Analysis, Fact or Fiction
- Journal of Analytical Toxicology: Testing Human Hair for Drugs of Abuse. I. Individual Dose and Time Profiles of Morphine and Codeine in Plasma, Saliva, Urine, and Beard Compared to Drug-Induced Effects on Pupils and Behavior
- Journal of the American Association of Medicine: Assessment of Commercial Laboratories Performing Hair Mineral Analysis
