Pediatric Marijuana Exposures in Colorado Increased Significantly After Recreational Legalization

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.

Wang, George Sam et al.·JAMA pediatrics·2016·Strong EvidenceRetrospective Cohort
RTHC-01294Retrospective CohortStrong Evidence2016RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Retrospective Cohort
Evidence
Strong Evidence
Sample
N=81

What This Study 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.

Key Numbers

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 They Did This

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.

Why This Research 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 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.

What This Study Doesn't 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.

Questions This Raises

  • ?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?

Trust & Context

Key Stat:
Pediatric marijuana poison center cases rose from 9 (2009) to 47 (2015) after Colorado legalization.
Evidence Grade:
Strong evidence from a well-designed retrospective study with clear temporal comparisons, published in JAMA Pediatrics with robust methodology.
Study Age:
Published in 2016. Subsequent studies have shown similar patterns in other states, and packaging regulations have been strengthened in response.
Original Title:
Unintentional Pediatric Exposures to Marijuana in Colorado, 2009-2015.
Published In:
JAMA pediatrics, 170(9), e160971 (2016)
Database ID:
RTHC-01294

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-ControlFollows or compares groups over time
This study
Cross-Sectional / Observational
Case Report / Animal Study

Looks back at existing records to find patterns.

What do these levels mean? →

Frequently Asked 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 More on RethinkTHC

Cite This Study

RTHC-01294·https://rethinkthc.com/research/RTHC-01294

APA

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

MLA

Wang, George Sam, et al. "Unintentional Pediatric Exposures to Marijuana in Colorado, 2009-2015.." JAMA pediatrics, 2016. https://doi.org/10.1001/jamapediatrics.2016.0971

RethinkTHC

RethinkTHC Research Database. "Unintentional Pediatric Exposures to Marijuana in Colorado, ..." RTHC-01294. Retrieved from https://rethinkthc.com/research/wang-2016-unintentional-pediatric-exposures-to

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.