Marijuana use among workers increasing, opioids decreasing

Due to the rise in marijuana use, the rate of workforce drug positivity hit a 14-year high in 2018, logging in at 4.4%.

Among the general workforce screening for opiates, positivity declined nearly 21 percent from a year earlier, the largest drop in three years and a nearly 37 percent decrease since the peak in 2015. (Photo: Shutterstock)

While the number of workers testing positive for use of opiates, heroin and cocaine has declined, positive tests for marijuana use are on the upswing—even for those in “safety-sensitive” occupations such as truck drivers and construction workers.

Indeed, due to the rise in marijuana use, the rate of workforce drug positivity hit a 14-year high in 2018, logging in at 4.4 percent, according to the latest Quest Diagnostics Drug Testing Index.

For all U.S. workers, marijuana positivity in urine testing rose nearly 8 percent from a year earlier, to 2.8 percent in 2018, an almost 17 percent rise since 2014. For the federally mandated, safety-sensitive workforce, which utilizes only urine testing, marijuana positivity rose nearly 5 percent from a year earlier, to 0.88 percent in 2018 a nearly 24 percent rise since 2014.

Related: Medical marijuana: A boon for older workers?

“Our in-depth analysis shows that marijuana is not only present in our workforce, but use continues to increase,” says Barry Sample, Quest Diagnostics’ senior director, science and technology. “As marijuana policy changes, and employers consider strategies to protect their employees, customers and general public, employers should weigh the risks that drug use, including marijuana, poses to their business.”

In the general U.S. workforce, the positivity rate for opiates in urine drug testing declined across all opiate categories. Among the general workforce screening for opiates (mostly codeine and morphine), positivity declined nearly 21 percent from a year earlier, to 0.31 percent in 2018—the largest drop in three years and a nearly 37 percent decrease since the peak in 2015.

Among the more specific tests for other prescription opiates, the positivity for the semi-synthetic opiates (hydrocodone and/or hydromorphone) declined from a year earlier, to 0.50 percent in 2018, a 43 percent drop since the five-year high in 2014. Similarly, the positivity for oxycodones (oxycodone and/or oxymorphone) declined more than 29 percent from a year earlier, to 0.43 percent in 2018, a more than 46 percent decline since the five-year high in 2014.

Urine drug test results for the general U.S. workforce for heroin, indicated by the presence of the 6-acetylmorphine (6-AM) metabolite, declined 6 percent from a year earlier, to 0.031 percent in 2018, a more than 16 percent drop since its peak in 2015 and 2016. Cocaine positivity declined nearly seven percent in urine and more than 19 percent in oral fluid testing, but increased slightly year-over-year (6.3 percent) in hair testing.

Both heroin and cocaine positivity in the federally mandated, safety-sensitive workforce showed large declines between 2017 and 2018. Heroin positivity declined nearly 32 percent from a year earlier, to 0.013 percent in 2018, a more than 43 percent drop since 2015. Positivity for cocaine declined nearly 10 percent from a year earlier — when the positivity rate was the highest in more than five years — to 0.28 percent in 2018.

However, the number of people testing positive for illicit drug use after accidents jumped – but that was due mainly by the addition of prescription opiates to the panel, according to Quest.

In the federally mandated, safety-sensitive workforce, positivity for post-accident urine testing jumped more than 51 percent from a year earlier, 4.7 percent in 2018, and by nearly 81 percent from 2014. Post-accident positivity in the general U.S. workforce rose 9 percent from a year earlier, 8.4 percent in 2018, a 29 percent rise over five years.

“Increases in post-accident positivity among safety-sensitive workers should serve as a warning to employers that employee drug use may increase the risk of workforce accidents or injuries” says Quest Diagnostics’ scientific director Kimberly Samano. “Our analysis suggests that employers committed to creating a safe, drug-free work environment should incorporate strategies that monitor drug use above and beyond pre-employment drug screening.”

Indeed, more workers are trying to “cheat the test,” as evidenced by a rise in urine specimens reported as invalid due to specimen adulteration or substitution. The percentage of invalid results in the federally mandated, safety-sensitive workforce jumped 80 percent from a year earlier, to 0.27 percent in 2018, and 40 percent in the general U.S. workforce, to 0.21 percent.

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