Record number of workers test positive for marijuana: study

9 to 5? More like 9 to 4:20.

Marijuana use among US workers reached “historic” highs in 2022, according to study findings released Thursday by Quest Diagnostics.

The lab company analyzed over 6 million general workforce urine tests in 2022, determining 4.3% were positive for cannabis, up from 3.9% in 2021.

That represents the highest number of marijuana-positive test results ever recorded by Quest, which began analyzing workplace drug-testing data in 1988.

Quest also found that 7.3% of workers who had suffered a workplace injury tested positive for marijuana in 2022, up from 6.7% in 2021 — marking the highest positivity rate in 25 years.


Man smoking weed wearing headphones.
Marijuana use among US workers reached “historic” highs in 2022, according to study findings released Thursday by Quest Diagnostics.
Getty Images/iStockphoto

“This historic rise seems to correspond with sharp increases in positivity for marijuana in both pre-employment and post-accident drug tests, suggesting that changing societal attitudes about marijuana may be impacting workplace behaviors,” Keith Ward, general manager and vice president for employer solutions at Quest, said in a statement. 

According to Quest, the industries that saw the greatest increase in their positivity rates over the past five years are: hospitality and food services (up 42.9%); retail (42.6%); and finance/insurance (38.5%).

And while marijuana was the drug most often discovered in the drug tests, tests also came back positive for amphetamines — rising from 1.3% in 2021 to 1.5% last year.

“The increase in amphetamines positivity is also notable, given the addictive potential and health risks associated with this class of drugs,” Ward said, pointing out that the company’s amphetamines data does not differentiate between prescribed medications and illicit drug use.


Graph from Quest Diagnostics.
Quest began analyzing annual workplace drug testing data in 1988. 
Quest Diagnostics

Dr. Suhash Harwani, senior director of science for employer solutions at Quest, noted the correlation between the positivity rates and states that have legalized recreational and medical marijuana.

Twenty-two states, two territories and the District of Columbia have enacted measures to regulate cannabis for adult non-medical use, while 38 states, three territories and DC allow the medical use of cannabis products, according to the National Conference of State Legislatures.

“In the general U.S. workforce, states that have legalized recreational and medical marijuana use exhibit higher positivity rates than the national average. States that have not legalized marijuana appear to have positivity rates below the national averages,” Harwani said in a statement.