Hair Testing For Drugs
If you are not already aware, or are considering an alternative testing methodology, you might be interested to know that hair testing for drugs is another service we offer. Hair can be tested to reveal 90 day drug use history.
There are a number of advantages that hair testing offers over alternative testing methods:
This testing method finds its niche in a testing setting where long-term use and dependency are in question. Hair testing will not, however, detect new or infrequent use as it does take time for testable levels of the drug to enter the hair specimen.
Hair follicles underneath the scalp are surrounded by a dense network of capillary blood vessels. Drugs in the bloodstream are able to incorporate and bind to the hair follicles underneath the scalp. It takes approximately 3-10 days for hair containing drug to reach the outer environment on top of the scalp to be collected based on the average rate of head hair growth. Head hair grows approximately 1.3 cm or ~1/2-inch per month. The standard length of hair tested by the laboratory is the first 3.9 cm or ~1 1/2 inches from the root end. Therefore, a hair analysis of 3.9 cm covers a time span of approximately 90 days and detects a pattern of drug use over this time-frame. Many employers find it useful to test both hair and urine for pre-employment purposes. Urine is useful for detecting recent or new drug use (last 1-3 days except Marijuana which is longer) and hair for providing an approximate three-month drug history.