What Causes False Positive Hair Follicle Test Result?
failed for meth and marijuana and what levels are acceptable ?
External contamination/adulteration might cause this!
Detailed Answer:
Hi!Thanks for writing to HCM!
Now-a-days, hair follicle/hair testing is an important tool in forensic/toxicology medicine as drugs stay in the hair! So detection is dependent on the length submitted for testing. A standard hair drug test is 1 ½” and detected up to 90 days of exposure and earliest by 7 days!
Following drugs are tested in 5 panel hair test: Marijuana (THC), Amphetamine, Cocaine, Opiates and Phencyclidine (PCP).
False positive results might come if External contamination/adulteration occurs to the sample before processing or before reaching to the laboratory!
Hope this answers your question.
If you need any further clarification please write to me.
Regards,