CORVALLIS, Ore. – A statewide study of more than 60,000 adult Oregonians shows that living near cannabis retail stores is associated with a greater tendency toward frequent cannabis use but a lower likelihood of heavy alcohol consumption.

The research led by Oregon State University scientist David Kerr looked at nine years of data from an ongoing telephone survey, the Behavioral Risk Factor Surveillance System directed by the Oregon Health Authority.

Participants in the survey didn’t need to know the locations of cannabis stores around them; that information was determined by linking participants’ ZIP codes with addresses of licensed retailers.

“The bottom line is that Oregonians who lived near more licensed cannabis retailers, and in closer proximity to them, were more likely to use cannabis 10 or more days per month than people living in areas with fewer retailers,” said Kerr, a professor of psychological science in OSU’s College of Liberal Arts. “Another key finding was that adults living closer to cannabis retailers were less likely to report heavy drinking.”

The U.S. Centers for Disease Control and Prevention define heavy drinking as eight or more drinks per week for women and 15 or more for men.

Kerr, who collaborated with OSU graduate student Haley Hummel and Multnomah County’s Julia Dilley and Erik Everson, noted that both effects – more cannabis and less alcohol – were most pronounced in two age groups: people ages 21-24 and those 65 and over.

In the younger age group, Kerr said, the brain is still developing, including parts of the brain sensitive to the toxic effects of cannabis. He notes ages 21-24 is the peak onset period for cannabis use disorder, which involves the continued use of cannabis despite negative consequences such as social or interpersonal problems, failure to fulfill obligations at home, school or work, and using cannabis under physically dangerous circumstances such as while operating a motor vehicle.

“These and other findings suggest that age-informed, multilevel prevention efforts are needed,” Kerr said. “Communities would benefit from a range of policies that respond to the growing evidence that cannabis products and retail stores are marketed in ways that are appealing to young adults, many of whom live in areas with lots of retail access and who are more apt to buy high-potency products.”

At the other end of the age spectrum, he said, perceptions about the risk of regular cannabis use have decreased in recent years, especially among people with chronic diseases who may use cannabis for medicinal purposes in ways that aren’t evidence based or that introduce new health risks.

“It’s a complicated picture,” Kerr said, “because cannabis is considered effective for certain conditions like chronic pain, it poses less risk than opioids, and less drinking is better for your health than more drinking.”

Kerr doubts people are choosing where they live based on the number of cannabis retailers nearby but rather that increased access to retailers may influence residents’ behavior.

Retail sales of recreational cannabis products in Oregon began in 2015. State law allows counties and cities to ban retail cannabis operations, but county bans apply only to unincorporated areas.

“Retail access to cannabis products can be regulated through an array of approaches and enacted at different levels of government,” Kerr said. “Careful consideration should be given to policies and prevention efforts that balance the goals of cannabis legalization against potential harms.”

This research was supported by the National Institute on Drug Abuse of the National Institutes of Health.

Findings, now available in preprint form, will be published in the American Journal of Preventive Medicine.

College of Liberal Arts

About the OSU College of Liberal Arts: The College of Liberal Arts encompasses seven distinct schools, as well as several interdisciplinary initiatives, that focus on humanities, social sciences, and fine and performing arts. Curriculum developed by the college’s nationally and internationally-renowned faculty prepares students to approach the complex problems of the world ethically and thoughtfully, contributing to a student’s academic foundation and helping to build real-world skills for a 21st century career and a purposeful life.