Drug Test Inaccuracies:

Lucy in the sky with a bladder infection

By Dr. Dean Edell

You've heard me speak out against drug testing. The most basic reason - even if we get past the privacy issues and issues about whether it has any effect on discouraging drug use - is that many of them are just plain inaccurate. Yet, people have lost their jobs due to false positives that turn up in a drug screen. And incidentally, they might never find out why.

The latest example comes from the Forensic Drug Abuse Advisor, and it concerns how one common test can give a false positive for the hallucinogen LSD. In fact, over an 18-month period when 1,256 urine samples were tested for drugs from the Wyoming Reproductive Health Study Program, 39 were found to be positive for LSD. Upon reevaluation, it was found that 38 of these were false positives.

While reanalyzing the samples, Microgenics Corp. discovered that women with bladder infections could end up with false positive results. The manufacturer realized this after E. coli bacteria grew out of two of the disputed urine samples.

It turns out a false positive reading can occur anytime a beta-galactosidase is in a sample. The problem is, this is an enzyme found in bacteria that frequently infect women's genitourinary tracts.

What I don't understand is why spend all this money and time to test women of child-bearing age for LSD when there's such a low rate of abuse of the hallucinagenic. Such programs keep women who need help for drug problems from seeking it for fear of retribution.