Positive Drug Tests of US Workers at Highest Level in a Decade

Author: David B. Weisenfeld, XpertHR Legal Editor

September 21, 2016

The percentage of employees testing positive for illegal drug use has reached a 10-year high, according to an analysis by Quest Diagnostics of nearly 11 million workforce drug test results. According to this annual survey, positive drug tests for marijuana, amphetamines and heroin have increased every year for the past five years.

One significant finding was the marked increase in heroin detection. While positive heroin tests accounted for less than one-tenth of 1% of all drug tests, they have increased overall by 146% since 2011, and by 84% in safety-sensitive positions.

Other notable results include:

  • Rising positivity rate for post-accident urine drug testing (up 30% since 2011);
  • Overall positivity in the US workforce was highest in hair drug tests (10.3%);
  • 45% of all workers who tested positive in 2015 did so for marijuana use; and
  • Marijuana positivity has increased 26% since 2011.

In speaking about the survey, Dr. Barry Sample, Quest's senior director of science and technology, said "Our nationally representative analysis clearly shows that drug use by the American workforce is on the rise, and this trend extends to several different classes of drugs and categories of drug tests."

The rise in positive marijuana tests mirrors the growth of marijuana legalization laws across the US. In all, 26 states have legalized medical marijuana use. Four of the states on that list - Alaska, Colorado, Oregon and Washington - plus the District of Columbia, also have legalized recreational marijuana use in limited quantities.

Nonetheless, employers generally remain free to discipline employees who fail drug tests because of medical marijuana use. Only three states offer protections to employees who fail drug tests because of such usage:

  • Arizona;
  • Delaware: and
  • Minnesota.

However, the issue remains one to watch as eight states will vote on a variety of marijuana legalization ballot measures this November.