Positive drug tests in U.S. workforce rise to 20-year high as marijuana is legalized

As some states have moved to legalize recreational marijuana, the overall workforce drug test positivity rate has climbed to a narrow, two-decade high across workers in all sectors, according to an analysis by Quest Diagnostics.

Broken out by industry, retail trade had the highest count of positive tests for all drugs—not just marijuana—in 2022 with 7.7%, followed by accommodation and food services (7.0%) and transportation and warehousing (5.3%). They were trailed by construction (4.7%), manufacturing (4.5%), and finance and insurance (3.6%).

Positivity rates for marijuana in the general U.S. workforce, based on more than 6.3 million urine tests, continued an upward climb, increasing to 4.3% in 2022—the highest positivity rate ever reported in the study—over 3.9% in 2021 and 2.8% in 2018.

The numbers come from the latest Quest Diagnostics Drug Testing Index (DTI) report. It covers the combined U.S. workforce, which includes both the general U.S. workforce of mostly company-policy testing by private employers and also the federally mandated, safety-sensitive workforce. Those covered under mandatory testing rules include federal employees and the transportation and nuclear power industries, spanning workers such as pilots, truck drivers, and train conductors.

However, marijuana testing rates were higher for those involved in accidents, the Secaucus, New Jersey company said. In 2022, post-accident marijuana positivity of urine drug tests in the general U.S. workforce was 7.3%, compared to 6.7% in 2021. That follows a steady increase in post-accident marijuana positivity every year from 2012 to 2022, doubling over that 10-year time frame.

These increases in post-accident marijuana positivity correspond with legalization of marijuana in certain states, Quest said. In 2012, Colorado and Washington became the first states to legalize marijuana for recreational use. Since then, 19 additional states and the District of Columbia have legalized the recreational use of marijuana and 38 states (plus the District of Columbia) have legalized medical use, although either kind of use remains illegal under federal law.

Looking at a wider spectrum of drug use, the combined U.S. workforce urine drug positivity in 2022 for all drugs persisted at 4.6% – the highest level in two decades. The 2021 and 2022 positivity rates were the highest since 2001, up more than 30% from an all-time low in 2010-2012.

While marijuana was the main driver of workforce positivity increases in the general U.S. workforce, amphetamines positivity also contributed to the increase. Positivity for marijuana in the general U.S. workforce increased by 10.3% (to 4.3% in 2022 versus 3.9% in 2021) and amphetamines positivity increased by 15.4% (1.5% in 2022 versus 1.3% in 2021). While that amphetamines data does not differentiate between prescribed medications and illicit drug use, the increase correlates with other data suggesting that the use of amphetamines, prescribed or illicit, has grown in recent years in the U.S., Quest said.