Workforce Drug Use Hits 14-Year High in 2018

Workforce Drug Use Hits 14-Year High in 2018

Marijuana use continues to increase, according to new analysis.

Workforce drug use continues to rise with positive drug tests hitting a 14-year high, according to new analysis from Quest Diagnostics.

The diagnostic information services company released its report which details how rapid legalization efforts are impacting positivity rates.

“Our in-depth analysis shows that marijuana is not only present in our workforce, but use continues to increase,” said Barry Sample, PhD, senior director, science and technology, Quest Diagnostics. “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.”

Positivity rates in the combined U.S. workforce in 2018 increased nearly 5% in urine drug tests, which is more than 25% higher than the 30-year low of 3.5% recorded between 2010 and 2012.

Marijuana continues to top the list of the most commonly-detected illicit substances across all workforce categories (general U.S. workforce; federally mandated, safety-sensitive workforce; and combined U.S. workforce, which includes the prior two populations) and specimen types (urine, oral fluid, and hair).

In the general U.S. workforce, marijuana positivity increased nearly 8% in urine testing (2.6% in 2017 versus 2.8% in 2018) and almost 17 percent since 2014 (2.4%).For the federally mandated, safety-sensitive workforce, which utilizes only urine testing, marijuana positivity grew nearly five percent between 2017 (0.84%) and 2018 (0.88%) and nearly 24 percent since 2014 (0.71%).

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% between 2017 and 2018 (0.39% versus 0.31%), the largest drop in three years and nearly 37% decrease since the peak in 2015 (0.49%). 

Urine drug test results for the general U.S. workforce for heroin, indicated by the presence of the 6-acetylmorphine (6-AM) metabolite, declined six percent (0.033% in 2017 versus 0.031% in 2018) and more than 16 percent since its peak in 2015 and 2016 (0.037%).

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%) 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% between 2017 and 2018 (0.019% versus 0.013%), with a decrease of more than 43% since 2015 (0.023%). 2018 positivity for cocaine declined nearly 10% compared with 2017 (0.31% versus 0.28%), when the positivity rate was the highest in more than five years.

In the federally mandated, safety-sensitive workforce, positivity for post-accident urine testing jumped more than 51% year-over-year (3.1% in 2017 versus 4.7% in 2018) and increased by nearly 81% between 2014 and 2018.

“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” said Kimberly Samano, PhD, scientific director, Quest Diagnostics. “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.”

Post-accident positivity in the general U.S. workforce climbed 9% year-over-year (7.7% in 2017 versus 8.4% in 2018), and 29% over five years. The post-accident positivity rate has risen annually since 2011 in the general U.S. workforce and since 2010 in the federally mandated, safety-sensitive workforce.

For an interactive map with positivity rates and trend lies by three-digit zip code in the United States, visit

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