A new study by researchers at Dartmouth has found that adolescents living in medical marijuana states with a plethora of dispensaries are more likely to have tried new methods of cannabis use, such as edibles and vaping, at a younger age than those living in states with fewer dispensaries. The study will appear in the August issue of Drug and Alcohol Dependence.

"This study was driven by two motivations -- the need to understand if and how the shifting legal landscape of cannabis may affect kids, and the potential utility of social media as an epidemiological sampling method," says Jacob Borodovsky, a PhD candidate at The Dartmouth Institute for Health Policy and Clinical Practice and the Center for Technology and Behavioral Health, and the lead author of the study. "If it is true that certain components of legalization change the way young people use cannabis, then we need to devote more resources to understanding the important consequences (good or bad) of the specific provisions included in the diverse cannabis laws that are emerging across the country."

Borodovsky and colleagues examined associations between provisions of legal cannabis laws (such as allowing dispensaries, home cultivation, etc.) and cannabis consumption patterns among youth using online surveys distributed through Facebook, which proved to be a reliable method for generating geographically diverse samples of specific subgroups of cannabis-using youth.

"Our data suggest a relationship between the degree of regulatory oversight of legal cannabis and kids' propensity for trying new ways of using cannabis," Borodovsky says. "I think we need to start having a broader national conversation about how best to design the production and distribution regulations for legal cannabis to mitigate potential public health harms."

As cannabis legalization rapidly evolves, in both medical and recreational usage, understanding the laws' effect on young people is crucial because this group is particularly vulnerable to the adverse effects of marijuana and possesses an inherent elevated risk of developing a cannabis disorder.

"Using social media to disseminate web surveys is a useful epidemiological research method. It allows us to quickly collect geographically diverse data on cannabis-related questions that aren't asked in the traditional federally-sponsored drug use surveys," Borodovsky says. "My hope is that we can use these and other types of results to create rational legal cannabis laws that are based on data rather than anecdotes."