Cannabis advertising impacts on youth cannabis use intentions following recreational legalization in Canada: An Ecological Momentary Assessment (EMA) study.

Objective: In 2018, Canada's Cannabis Act legalized adult recreational cannabis use and limited cannabis product advertising to adults. Cannabis product advertising to youth remains illegal. The extent to which adult-targeted, or illicit youth-targeted cannabis advertisements is reaching and impacting Canadian youth is unknown. We used Ecological Momentary Assessment (EMA) to describe how often and how much exposures to cannabis advertising influence Canadian youths' real-world, real-time intentions to use cannabis.

Methods: 120 Ontario, Canada youths ages 14-18, took photos of cannabis advertising that they encountered in their natural environments over a period of nine consecutive days. Following each exposure and twice daily device-issued random prompts, they also rated their intentions to use cannabis.

Results: Many participating youth (n = 85; 70.83 %) reported at least one cannabis advertising exposure during the study (range 1-30, M = 4.02). Exposures occurred through a range of advertising channels (e.g., internet ads, billboards). Multilevel modeling showed that youth advertising exposure increased cannabis use intentions in vivo (β = 0.06,SE = 0.03;t = 1.98;p =.04;n = 1,348).

Conclusion: Data from this study shows that cannabis advertisements are regularly reaching Canadian youth and increasing their intentions to use cannabis. This suggests that current Canadian prohibitions on cannabis advertising to youth are ineffective and/or ineffectively enforced, and that the Canadian government needs additional or enhanced prohibitions on cannabis promotion to protect youth from harms associated with increased advertisement exposure, such as increased cannabis use.