Frequently Asked Questions

  • Q: What is a preliminary test?

    A: A preliminary test is a single test result based on an initial screen.

  • Q: What is a confirmation test?

    A: A confirmation test is a second test which offers a more specific chemical method for the detection of the desired substance. The preferred confirmation method is gas chromatography/mass spectrometry (GC/MS)

  • Q: Why is a confirmation test necessary?

    A: The purpose of a confirmation test is to eliminate any false positive results that may have originated from an initial screening.

  • Q: What is adulteration?

    A: Attempts to adulterate urine drug tests can occur in three ways: dilution, substitution, or interference.

  • Q: Can eating poppy seeds cause a false positive drug test for heroin?

    A: Eating poppy seeds cannot turn a drug test positive for heroin. However, poppy seeds do contain morphine. Therefore, eating poppy seeds (e.g., a poppy seed bagel) can result in a “true” positive result for opiates, more specifically, morphine. Testing for opiates and the subsequent search for a metabolite that is exclusive to heroin called 6-acetylmorphine (6-AM) during the confirmation testing phase, it is very unlikely a false positive for heroin will occur.

  • Q: Can passive inhalation of marijuana cause a false positive drug test?

    A: Sometimes employees who test positive for marijuana will claim it was the result of passive inhalation – “I was at a party last night and other people were smoking dope, not me. But I think I inhaled some of the smoke.” The likelihood that an individual would inhale enough marijuana smoke to produce a positive drug test result at the cut-off levels currently observed by most drug testing labs (50 ng/mL) is virtually nonexistent. The person may have some traces of the drug in his system but not enough to register positive at a cutoff level of 50 ng/mL

  • Q: Can over-the-counter cold medications cause false positives?

    A: Here’s another reason why companies should only test with labs that guarantee the use of GC/MS confirmation. Some over-the-counter (OTC) medications can turn an initial screen for amphetamine positive because of the structural similarities between the various OTC drugs and amphetamine. However, these OTC drugs will not interfere with the GC/MS confirmation.

  • Q: What is Ecstasy?

    A: MDMA, often known on the streets as “ecstasy” or “Adam,” is structurally similar to methamphetamine. MDMA stimulates the central nervous system and produces hallucinogenic effects. In order for a drug test to detect ecstasy, it must be able to detect MDMA.

  • Q: What can an employer do if an employee tests positive?

    A: An employer can offer treatment assistance to an employee who tests positive. This can be as simple as a listing of local or national providers or as comprehensive as an employee assistance program (EAP) or health care benefits that offer drug treatment.

  • Q: What are drug detection periods?

    A: The average amount of time that certain drugs tend to stay in a person’s system is referred to as the drug detection period. Refer to Approximate duration of detect ability of selected drugs in urine for some examples of approximate guidelines