How Can a Drug Test Come Back Positive for Cocaine?
Question by Laurel: How can a drug test come back positive for cocaine?
How much is 624pg/mg of cocaine on a drug test. What can make.a drug test come back positive for cocaine but not conaine its safe?
Best answer:
Answer by djp245
pg/mg (picograms per milligram) is used to describe a quantitative range in hair analysis drug screening. A positive is confirmed for ranges at or above 500pg/mg. Low-dose usage is indicated between 500-2500pg/mg.
It is possible to have a false positive for cocaine use, but only from urine-based testing:
“Urine based tests have been upheld in most courts for more than 30 years, however, urinalysis conducted by the Department of Defense has been challenged for reliability of testing the metabolite of cocaine. There are two associated metabolites of cocaine, benzoylecgonine (BZ) and ecgonine methyl ester (EME), the first (BZ) is created by the presence of cocaine in an aqeous solution with a pH greater than 7.0, while the second (EME) results from the actual human metabolic process. The presence of EME confirms actual ingestion of cocaine by a human being, while the presence of BZ is indicative only. BZ without EME is evidence of sample contamination, however, the US Department of Defense has chosen not to test for EME in its urinalysis program.” – (taken from wikipedia)
I am not sure whether a false positive for cocaine is possible in hair tests, but I do know that it can be detected in hair for up to a year after previous exposure.