Newswise — As of March 2022, 18 states and the District of Columbia allow recreational use of marijuana among adults 21 years and older, and recreational marijuana sales is legal in 14 of these states. A new study of the commercial availability of alcohol and marijuana in California, and the likelihood of alcohol and marijuana co-use among 9th and 11th grade students, has found increased co-use among the general high school population. These results and others will be shared at the 45th annual scientific meeting of the Research Society on Alcoholism (RSA) in Orlando, Florida.

“In November 2016, the voters of California approved adult recreational use of cannabis, which allowed adults aged 21 years or older to possess and use marijuana for recreational purposes,” explained Sharon O’Hara, a postdoctoral research fellow at the Pacific Institute for Research and Evaluation. “We were concerned about the increasing use of marijuana among underage youth, and its use in combination with other substances like alcohol. There is evidence that alcohol and marijuana co-use may increase the risk of adverse outcomes beyond using either substance alone.”

The study focused on not only the effects of the “normalization of marijuana use,” but also the increased commercial and social availability of marijuana at state and local levels. O’Hara and her colleagues will discuss these findings at the RSA meeting on Monday, 27 June 2022.

This study used data from ninth and 11th-grade students who participated in the California Healthy Kids Survey (CHKS), a statewide biennial, anonymous, and confidential survey of health-related behaviors, including alcohol, tobacco, marijuana, and other drug use. Researchers computed on- and off-premise alcohol and marijuana outlet densities for 38 California cities. Analyses were conducted to examine relationships among local alcohol and marijuana outlet density, students’ perceived availability of alcohol and marijuana, and the likelihood of their co-use of alcohol and marijuana after passage of the state law allowing recreational marijuana use.

“It appears that recreational marijuana legalization is having an effect on the perceived availability of marijuana among high school students in California,” said O’Hara. “Legalization and greater retail availability seem to be having some effect on increased co-use in the general high school population, with significant effects on co-use among subgroups of youth who are at least occasional or heavy drinkers.” O’Hara believes that a more permissive state and local cannabis environment can lead to an increased acceptability of cannabis use and greater access to cannabis for underage youth.

“Even if recreational marijuana is legalized at the state level, both state and local policies can focus on how accessible marijuana is to youth in their communities,” added O’Hara. “Local jurisdictions and the public can consider what they can do to make it harder for underage youth to get marijuana. For example, some local jurisdictions in California are using land use/zoning authority to limit the number, type, location, and operating conditions of retail cannabis businesses, in order to limit youth exposure and access.”



Meeting Link: RSA 2022 meeting