A new study tracking hospitalizations for poisonings in children aged nine and under suggests the rate of pediatric hospitalizations caused by cannabis more than doubled in provinces that permitted the sale of cannabis edibles.
In Ontario, Alberta and B.C., around one-third of all pediatric hospitalizations for poisoning were due to cannabis, the study found.
The study, published in the peer-reviewed journal JAMA Health Forum, looked at not only the rate of hospitalizations before legalization, but also during the period of time in which cannabis was legalized but regulated edible cannabis products had not yet hit the shelves, a distinction which allowed researchers to compare the impact of the legalization of dried cannabis with the legalization of edibles.
Its findings echo earlier research from August that found that provinces that legalized cannabis edibles in early 2020 saw an increase in accidental cannabis poisonings among children – more than double that of Quebec, where the sale of edibles is prohibited.
Cannabis was legalized across Canada in 2018, but at that time, regulations did not include the sale of edibles. Only the dried cannabis flower was permitted to be sold, with the federal government later allowing provinces the option to permit the sale of other cannabis products, including edibles, or not.
Starting in January 2020, Ontario, Alberta and B.C. legalized the sale of cannabis edibles, including gummies, candies, chocolates and baked goods. Quebec's provincial government decided to prohibit the sale of these products, allowing only the sale of tetrahydrocannabinol-infused beverages.
The decision provided an opportunity for researchers to compare the provincial data in the same time period to see if the legalization of edibles made a clear difference.
For this study, researchers looked at hospitalizations of children aged zero to nine in Ontario, Alberta, B.C. and Quebec between January 2015 and the end of September 2021, a period of time spanning the pre-legalization period, the period in which cannabis products other than edibles were legalized, and the period in which edibles were legal in some provinces.
The records of more than 3.4 million children were included in the research.
Across the entire study period, there were 4,406 hospitalizations for all-cause poisonings in children aged nine and under, 581 of which were for cannabis poisoning.
The average age of child brought to the hospital with cannabis poisoning was three to four years old. Tetrahydrocannabinol, or THC, is the main psychoactive ingredient in cannabis.
Prior to any cannabis legalization, around 57 out of 1,000 pediatric hospitalizations for poisoning was due to cannabis in Ontario, Alberta and B.C. The rate was 38.5 out of 1,000 in Quebec.
After cannabis was legalized in 2018, the rate increased for all four, with Ontario, Alberta and B.C. seeing the rate increase to 150 per 1,000 and Quebec seeing it increase to 117.5 out of 1,000.
Once edibles were legalized in Ontario, Alberta and B.C., the rate of hospitalizations due to cannabis poisoning more than doubled, based on the data, with cannabis registered as the cause behind 318 out of 1,000 pediatric hospitalizations for poisoning.
During the same time period, the rate of cannabis poisonings out of all poisonings only increased slightly in Quebec, to 138 out of 1,000.
The vast difference between the three provinces that did legalize cannabis edibles and the one that did not suggests that policy may play a role in these accidental poisonings.
Regulators have long been concerned about the idea of edibles — which don’t look any different from regular chocolate or candies once outside of their packaging — accidentally being picked up by young children, with Health Canada stipulating a maximum of 10 milligrams of THC per edible package and requiring packaging to be designed in a way that wasn’t appealing to children.
Previous studies have looked at the rate of cannabis poisonings in children before and after legalization, but researchers noted that they wanted to look at cannabis poisonings among all-cause poisonings in order to remove the confounder of the pandemic itself; since many children were at home more during the early days of the pandemic due to school closures, it’s possible that all poisonings were increasing.
However, the increase in the rate of cannabis poisonings compared to all-cause poisonings seems to suggest that the issue cannot be fully explained just by the pandemic.
“Our findings suggest that placing restrictions on the sale of visually attractive and palatable commercial cannabis edibles is a key strategy and policy consideration for preventing unintentional pediatric cannabis poisonings for the U.S. and other countries considering legalization of recreational cannabis,” the study author’s stated in its conclusion.
