Dias Argandykov, MD, a surgical resident at Massachusetts General Hospital, is lead author of a new study in the journal Injury Prevention, Recreational Cannabis Legalization and Pediatric Exposures in Massachusetts, United States. Michael Flaherty, DO, a pediatric critical care physician at Mass General for Children, is senior author, and Toby Raybould, Trauma Prevention Manager at Mass General, is among the authors.

What was the question you set out to answer with this study?

We were interested in finding out if the legalization of recreational cannabis (RCL) in Massachusetts impacted the number and rate of ED and in-patient hospitalizations of unintentional cannabis ingestion among people ages 0-19.

In other words, did the legalization of recreational marijuana lead to unintentional use by children and adolescents?

What Methods or Approach Did You Use?

To compare the incidences before and after RCL in Massachusetts, US, we queried the data on pediatric cannabis exposure cases in 2016–2021 from the Center for Healthcare and Analysis and Injury Surveillance Program provided by the Massachusetts Department of Public Health.

The pre-and post-legalization phases comprised the periods between 2016–2018 and 2019–2021, respectively.

Cannabis-related exposure cases included ED visits and hospitalizations among children and young adolescents of 0–19 years old.

What Did You Find?

Cannabis-related ED visits and hospitalizations among children and teenagers increased from 18.5 per 100,000 people to 31.0 per 100,000 people during the six-year period after recreational cannabis became legal in Massachusetts.

Children in the age groups 0-5 and 6-12 years experienced the highest rates in cannabis-related ED visits.

The most significant increase in ED visits related to cannabis exposure was observed among children aged 6–12 years—more than seven times higher than in the pre-legalization period.

The incidence rate in the youngest group of patients (0–5 years) increased by more than four times following the policy implementation.

There were zero cannabis intoxication or poisoning-associated deaths reported between FFY 2016–2021.

The incidence of cannabis-related hospitalizations increased from 3.5 per 100 000 population to 7.9 per 100,000 population, a 126% increase.


Our study demonstrates increases in the incidences of ED visits and hospitalizations among children and young adolescents due to cannabis exposures following the recreational cannabis policy implementation (2019–2021) in Massachusetts. Our findings contribute to the growing body of evidence linking the availability of recreational cannabis products and increased pediatric cannabis exposures.

These findings suggest that commercially available cannabis products, while not intended for use by children, are being unintentionally consumed by the youngest children.

While our study lacks data on the types and appearance of cannabis products, the resemblance of manufactured edible cannabis products to commercially available candy has been previously highlighted as a public health concern.

Our analysis also extends the existing evidence from other US states and Canada, indicating the increased burden associated with cannabis exposure among children after recreational cannabis legalization and implementation.

These trends of unintentional pediatric cannabis exposures persist despite strict regulations, including child-resistant packaging, warning labels, and attempts at minimizing the appealing resemblance to commercially available products.


Paper cited:

Argandykov, D., Raybould, T. A., Gervasini, A., Hwabejire, J., & Flaherty, M. R. (2024). Recreational cannabis legalization and pediatric exposures in Massachusetts, United States. Injury prevention : journal of the International Society for Child and Adolescent Injury Prevention, ip-2023-045052. Advance online publication. https://doi.org/10.1136/ip-2023-045052

About the Massachusetts General Hospital

Massachusetts General Hospital, founded in 1811, is the original and largest teaching hospital of Harvard Medical School. The Mass General Research Institute conducts the largest hospital-based research program in the nation, with annual research operations of more than $1 billion and comprises more than 9,500 researchers working across more than 30 institutes, centers and departments. In August 2023, Mass General was named to U.S. News & World Report’s list of "America’s Best Hospitals." MGH is a founding member of the Mass General Brigham healthcare system.