Post-Accident Marijuana Testing Update—Positivity Rate Skyrockets Over 200%

Some bad news has come in from Quest Diagnostics. The company conducts a large proportion of U.S. drug testing. They compile, track, and release population-level results to supply insights on Americans’ drug use and possible workplace impacts.

As the most recent report demonstrates, there is a clear trend toward more cannabis use across the country and potentially more consequences on the job.

The Findings: More Workers Test Positive for Cannabis

This one may not come as a surprise. As more and more states have legalized marijuana—for medicinal use, recreational use, or both—cannabis use is showing up on more drug tests. Of particular concern are post-accident drug tests, where employers are striving to determine if impairment contributed to a safety incident.

Sadly, post-accident workforce drug positivity for marijuana has reached a 25-year high. Specifically, positive urine tests following an accident increased 9% between 2021 and 2022. Today, 7.3% of these tests return positive.

The change is even more alarming when considered over the ten-year timeframe from 2012, when the first states legalized marijuana, and 2022, the most recent full-year data. Over the course of a decade, post-accident marijuana positivity rates increased 204.2%.

The shift extends beyond post-accident testing as well. The general U.S. workforce positivity rate also reached its highest level in 20 years. As one might expect, positive rates are not increasing as quickly (although they are increasing) in states where neither medical nor recreational cannabis is legal.

Some Perspective: Testing Doesn’t Provide the Complete Picture (Yet)

First, we should note that across the entire U.S. workforce, positive rates on cannabis testing reached 4.3%, still a small minority of employees. For post-accident tests, 7.3% return a positive reading for marijuana. The vast majority of safety incidents are not accompanied by a positive cannabis test, but employers should still be concerned about the upward trend.

Additionally, results are open to some interpretation. On the one hand, as Katie Mueller from the National Safety Council points out in the Quest article linked above, "Intoxicating cannabis products, including marijuana, can have a major impact on safety at work and have been proven to slow reaction time, impact memory and impair skills essential to driving.”

But are more employees using at work or immediately before, or are they using during their time off in ways that don’t affect their jobs? Are employees more likely to be working in an impaired state, or do these tests reflect societal acceptance of cannabis use during leisure hours? The situation remains unclear.

That’s because the Quest statistics are based on urine tests for THC metabolites, which are present within a few hours of use, not immediately upon use, and may persist for about a month. The year-over-year comparisons, therefore, tell us a lot about cannabis use as a lifestyle choice but less about precisely when workers are using and how their choice is affecting on-the-job performance and safety. Additional research would be needed to determine actual use patterns and correlate them with workplace safety and employee productivity effects.

Even with these caveats, a steep rise in post-accident positivity rate compels a serious look from employers interested in risk mitigation. At Asurint, we’ve been tracking advances in drug testing tools, regulations, and expert recommendations to help make employers aware of their options and the considerations that surround them.

Asurint Resources For You

We would highly recommend Marijuana & Beyond and The Advantages of Breath Testing for Recent Cannabis Use, two webinars that together cover marijuana-related topics in comprehensive detail. And definitely grab our 50 State Guide: Drug Testing Laws to identify legal and regulatory changes in jurisdictions where you operate, recruit, or maintain remote employees.

None of these tools should be considered legal counsel—you should obtain your own legal advice when setting policies and procedures—but we hope they help illuminate some of the issues involved in the very confusing topic of cannabis and workplace safety.