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Teen Weed Use Has Declined Since Washington Legalized Adult-Use Cannabis

The worry that legalization would increase underage use has generally proved unfounded.

Opinions expressed by Entrepreneur contributors are their own.

After cannabis became legal for recreational use in Washington state, use of weed dropped in among almost all groups of high schoolers and middle schoolers, according to a study from Washington State University.

David Ryder | Getty Images

Washington became one of the first states to approve adult-use marijuana sales, with the first dispensaries opening in 2014. Then, as now, one of the arguments against legalization was that it would lead to increased use by teenagers.

The study, published in the Journal of Adolescent Health, found just the opposite happened with most teens. Led by Washington State University College of Nursing Assistant Professor Janessa Graves, the study found only one group of teens increased marijuana use: 12th graders who work.

Related: New Poll Finds Highest Support Ever for Weed Legalization

Working teens and marijuana.

Graves was joined on the project by researchers from the University of Massachusetts - Amherst, University of Colorado and the Oregon Health Authority. The researchers found use went down among teens in the 8th and 10th grades, as well as with 12th graders who didn’t work.

For 12th graders who worked less than 11 hours a week, cannabis used remained about the same. However, for 12th graders who worked more than 11 hours per week, use increased. Also, across all age groups, those who worked reported using cannabis more than those in their peer group who did not work.

The researchers classified work as jobs other than babysitting, yardwork or household chores. Researchers used information from the 2010 and 2016 Healthy Youth Survey conducted in Washington.

Related: Managing Medical Marijuana in the Workplace

Why the exception?

Clearly, the numbers are encouraging for those concerned about legalization leading to increased teen marijuana use. Graves told Science Daily that the numbers reflect common sense. Working teens are exposed earlier than their peers to both the positive and negative influences of adults.

Graves said, "Kids learn a lot by working, in terms of responsibility. But there are also pretty good data showing that kids who work engage in adult-like behaviors earlier. I would say this for any parent of working kids: It's important to know the quality of management and supervision at your child's job. Be thoughtful about the quality of a particular workplace."

As the study shows, the issue with legal marijuana isn’t so much with teens as it might be with adults, including those who supervise and work with teens on the job. The study writers recommend that employers consider advertising and enforcing zero-tolerance policies toward any adult workers who endorse or provide marijuana or any other substances to underage workers.

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