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The Worker Institute brings together researchers, educators and students with practitioners in labor, business and policymaking to address issues related to confronting systemic inequality and building a fair economy, robust democracy and just society. We will share opinion, analysis, research, data, insights and training from our faculty and staff.

Marijuana and the Workplace

Federal and State Laws

As states legalize medical or recreational marijuana, employers, employees and unions are asking how to keep people safe in the workplace.

Some of them, including the Center for Occupational & Environmental Medicine in Western New York, are turning to ILR’s Nellie Brown.

“When I started looking at this, several things really jumped out at me,” said Brown, a certified industrial hygienist and lead programs manager at The Worker Institute at Cornell.

Marijuana use can cause drowsiness, lack of concentration and impaired learning and memory, but these effects wear off 48 hours after use, she said. About two million people in the United States have marijuana prescriptions.

Maryland is in the midst of determining workplace guidelines for legalized marijuana use; other states have established rules and a number of states are unclear about workplace implications around the drug, according to The Baltimore Sun.

Brown said that the drug tests most employers relay on only detects the compound in marijuana that remains in the liver a month after use. A test for more recent use would be much more expensive.

“You could have a medical marijuana user on family medical leave urine tested upon return to work who could be terminated,” she said, even though the worker hadn’t used marijuana recently enough to be impaired.

Employers are beginning to request training in how to recognize impairment, similar to the way many managers now look for signs of alcohol impairment, Brown said.

“Employers have been very interested in the issue of impairment and liability,” she said. Insurance is an issue, as well as Workers Compensation, which doesn’t cover impaired workers. Not only are there safety questions, but productivity issues.

In many cases, employers could address safety concerns by consistent scheduling, Brown said.

Much of the confusion in the United States occurs because the issue is addressed by both states and the federal government, versus in other countries, where the question is exclusively a national one, Brown said.

Plus, she said, Attorney General Jeff Sessions reversed an Obama directive that had prevented the federal government from pursuing marijuana cases in states that have legalized it. “We really have an actual, serious mess,” Brown said.

Brown recently gave a presentation to the Center for Occupational & Environmental Medicine’s advisory board, and she will give a similar presentation to an area labor union.

Among the issues are whether marijuana is ingested, such as when it is eaten in brownies or smoked, she said.

The effect peaks slower but lasts longer when eaten, Brown said. Also, marijuana grown today is more potent. “People are afraid of passive exposure now,” she said. “Passive inhalation may be a real danger. It’s a bit of an open question.”

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