Cannabis is widely legalized, but it’s still controversial. Studies continue to show it offers benefits and downsides. Recent research finds workers that who use cannabis are more likely to be injured on the job.

But the findings are only relevant to workers who consume during work hours. They do not apply to those who consume after work and on days off.
About the Study Regarding Workers Who Use Cannabis
The study, which was published in the Canadian Journal of Public Health, focused on 2745 Canadian workers in safety-sensitive and non-safety-sensitive positions over the course of two years. 11.3% were injured during the study.
Research revealed that 10.2% of injured participants identified as nonusers. 11.14% used only after work or on days off. 20.13% of workers who use cannabis consumed it shortly before starting their workday or during their workday.
The study further broke down the results of safety-sensitive and non-safety-sensitive workers. Findings showed that 20.14% of safety-sensitive workers who were injured were non-users, 23.3% consumed marijuana during non-work hours only, and 31.35% consumed shortly before or during work hours.
4.27% of injured participants in non-safety sensitive jobs were non-users, 4.19% used during non-work hours, and 12.3% of workers who use cannabis consumed during work hours.
Timing Matters
The authors of the study on workers who use cannabis state their findings “bring greater clarity to the question of whether cannabis use increases the risk of experiencing a workplace injury, an issue that the conflicting findings of previous studies have hampered”. They referred to prior research which was limited by a failure to account for timing in relation to consumption and workplace injuries.
“Findings suggest that, when thinking about the potential occupational safety impacts of a worker’s cannabis use, it is important to consider when that use is taking place,” it says. “More specifically, only use in close temporal proximity to work appears to be a risk factor for workplace injuries, not use away from work,” the study went on to state.
Summing Up
The authors of the study on workers who use cannabis summed up their findings with the following statements.
“Compared to no past-year use, the risk of experiencing a workplace injury was 19.7 times higher among workers reporting workplace use. No statistically elevated association was seen for non-workplace use,” the study said.
“Results of this novel study suggest workplace cannabis use, not outside of work, is a risk factor for workplace injuries,” the authors concluded.
They also stated that “only workplace cannabis use poses a risk to future workplace safety,” whether the job is safety-sensitive or not.
What the Study Means for Mandates on Marijuana Use in the Workplace

Cannabis legalization has caused many businesses and workers to question mandates that exist regarding cannabis testing and use in the workplace. Does this new study on workers who use cannabis shed light on the matter?
“The findings also do not diminish employers’ legitimate concerns regarding workplace impairment. Nonetheless, zero-tolerance policies that prohibit cannabis use entirely, including use outside of work, may be overly broad and are incompatible with the results of this study.
“An increasingly legalized environment, more nuanced approaches to workplace policies around cannabis use may be warranted and could include employing minimum waiting periods after cannabis consumption when impairment is most likely present,” the study states.
Other Studies
Recent research shows that workers who use cannabis during work hours are more likely to incur work-related injuries. But other studies show cannabis use can be beneficial in the workplace.
A 2021 study published by the National Bureau of Economic Research found that cannabis use was associated with a decrease in work-related injuries and an increase in productivity.
A 2019 study shows that cannabis use resulted in fewer workers’ compensation claims thereby saving businesses money.
Businesses Scale Back on Cannabis Testing
Cannabis was once a no-no for many employers. Businesses saw it as a threat to safety and productivity. But now, many businesses are loosening up on rules concerning workers who use cannabis.
A Bloomberg Law article states that many companies are seeking legal advice to find a solution that balances workplace safety without letting weed get in the way of finding the best talent for a position.
The number of workers who use cannabis went up by 10.3% from 2021 to 2022 thanks to increasing legalization measures. The rising numbers make it more difficult for companies that test to find qualified employees.
Employers are dropping pre-employment testing to make it easier to recruit for certain positions. Notable companies that have no longer require cannabis testing include Amazon, Auto Nation, and Cesar’s Entertainment.
The shift has also been seen in professional sports. The Major Basketball League and National Hockey League have removed marijuana from their prohibited substances list.
Safety is a Concern
Employers don’t want drug testing to interfere with finding the best talent. But safety remains a concern among workers who use cannabis.
Alexa Miller, a partner at Faegre Drinker Biddle & Reath, LLC recommends that employers in non-safety-sensitive industries move away from drug testing and only employ it after an accident occurs or if there is suspicion of drug use.
A Move to Saliva Testing

Employers have also moved away from blood, urine, and follicle testing which tests for long-term use. Instead, they are focusing on saliva testing which determines if marijuana has been used in the last 24 hours. The new method will show companies whether their employees were high on the job.
Saliva testing helps enforce new laws that will take effect in California and Washington next year that prohibit businesses from firing workers who use cannabis if they can’t prove the employee was high on the job.
The U.S. Department of Transportation has adopted a new rule to use saliva testing for pre-employment, post-accident, and before returning to duty. The rule is on hold pending government testing.