Hair Testing Facts

This testing method provides highly accurate, quantitative data on long term drug use for up to 90 days prior to the test date.  Hair testing will yield up to three times as many positive users than urine, making it a proven alternative testing method.  In addition, sample adulteration concerns are greatly reduced, as with the theory of washing hair will “dilute” the sample.

In most cases, hair testing would not be appropriate for post accident or reasonable suspicion testing.  Current use of illegal drugs will not show up in hair until after about seven days.  For pre-employment and random testing, use of hair as the specimen to be tested will yield results as to the donor’s history of drug use going back about 90 days.  Experts now believe that the ultimate drug test is a combination of hair testing and a urine test. 

With hair testing the donor goes into a collection site, provides a hair specimen, which goes out to a lab, and the results are then reported by a certified Medical Review Officer (MRO).  A small amount of hair is taken and no visible sign of the cut hair remains.  Those with less than one inch of head can provide body hair.  The lab performs an initial screen on the specimen and a GC/MS confirmation test if non-negative.  Turnaround time is 2-3 business days for negative and 5-6 business days for non-negatives.  Turnaround time is 2-3 days for negatives and 5-6 business days for non-negatives.  With hair testing, typically five panel of drugs of abuse will be tested. 

Like urine testing, hair testing does not provide evidence of current impairment, only past use of specific drug.  Hair testing cannot be used to detect alcohol.  Again the main advantage of hair testing is prevention of adulteration, ease of collection and hair analysis can detect drug use for approximately the previous 90 days.  The disadvantage is that it is more expensive, about twice the cost of lab based urine testing.