Pediatric Marijuana Exposures in Colorado Increased Significantly After Recreational Legalization | Research

The takeaway

After Colorado legalized recreational marijuana, pediatric marijuana exposures at a children's hospital nearly doubled, poison center cases increased five-fold from 2009 to 2015, and edibles were responsible for about half of all exposures.

Read this if you have children and live in a state with legal cannabis, or if you work in pediatric health or cannabis policy.

Pediatric marijuana poison center cases rose from 9 (2009) to 47 (2015) after Colorado legalization.

What the researchers found

Researchers examined unintentional marijuana exposures in children under 10 at Children's Hospital Colorado and the regional poison center from 2009 to 2015, spanning the periods before and after recreational marijuana legalization.

The rate of marijuana-related visits to the children's hospital nearly doubled, from 1.2 per 100,000 to 2.3 per 100,000 in the two years before versus after legalization. Annual poison center cases increased more than five-fold, from 9 in 2009 to 47 in 2015.

Colorado's increase (34% per year) outpaced the rest of the United States (19% per year), though both were increasing. The median age of affected children was about 2 years.

Edible products were responsible for roughly half of all exposures. Child-resistant containers were absent in 9% of known scenarios, and poor supervision or storage was reported in 34%. Almost half of children's hospital patients in the two years after legalization were exposed to recreational (not medical) marijuana.

Why it matters

This is one of the most cited studies on the unintended pediatric consequences of marijuana legalization. It demonstrated that legalization led to more children accidentally ingesting marijuana, particularly edible products that can look like candy or treats. The findings influenced child-resistant packaging and dosage labeling regulations in multiple states.

The numbers in context

81 children's hospital patients. 163 RPC cases. Median age: ~2 years. Hospital visit rate: 1.2 to 2.3 per 100,000 (p = 0.02). RPC cases: 9 (2009) to 47 (2015), 5-fold increase. Colorado increase: 34%/year vs US: 19%/year. Edibles: ~48-52% of exposures. Median hospital stay: 11 hours (26 hours if admitted).

How the study worked

Retrospective cohort study of marijuana exposures in children 0-9 years at Children's Hospital Colorado (81 patients) and Colorado Regional Poison Center (163 cases) from January 2009 through December 2015. Rates were compared between the 2-year periods before and after recreational legalization. RPC trends were compared with the rest of the United States.

What this study cannot tell us

Retrospective design relies on cases that were brought to medical attention. Less severe exposures may not have resulted in hospital visits or poison center calls. The study cannot definitively attribute all increases to legalization, as other factors (increased awareness, changing reporting practices) may contribute. The study covers only one state and one children's hospital.

How to read the evidence

Strong evidence from a well-designed retrospective study with clear temporal comparisons, published in JAMA Pediatrics with robust methodology.

When this study was published

Published in 2016. Subsequent studies have shown similar patterns in other states, and packaging regulations have been strengthened in response.

The bigger picture

As more states legalize marijuana, the Colorado experience serves as a case study for pediatric safety. The prominence of edibles in these exposures led to reforms in product packaging, labeling, and dosage limits. States that legalized later incorporated many of these lessons into their initial regulations.

Questions still open

Have child-resistant packaging regulations reduced pediatric exposures in states that implemented them? How do pediatric exposure rates compare in states that legalized later with stronger regulations? What are the long-term health consequences, if any, of early childhood marijuana exposure?

Common questions

Are children at risk from marijuana edibles?

Yes. This study found edibles were responsible for about half of unintentional pediatric marijuana exposures. Children as young as 1-2 years were affected, and some required hospitalization averaging 26 hours. Edibles can look like candy or snacks, making them attractive to young children.

Did legalization cause more kids to be exposed to marijuana?

In Colorado, pediatric exposures nearly doubled at the children's hospital and increased five-fold at the poison center after recreational legalization. Colorado's increase also outpaced the national trend, suggesting legalization contributed to the rise.

Read the original research

Unintentional Pediatric Exposures to Marijuana in Colorado, 2009-2015.

JAMA pediatrics, 170(9), e160971

View on PubMed ↗Publisher’s paper ↗

Citation

Wang, George Sam; Le Lait, Marie-Claire; Deakyne, Sara J; Bronstein, Alvin C; Bajaj, Lalit; Roosevelt, Genie. (2016). Unintentional Pediatric Exposures to Marijuana in Colorado, 2009-2015.. JAMA pediatrics, 170(9), e160971. https://doi.org/10.1001/jamapediatrics.2016.0971