Overdose Incidence Rises in Toronto Neighbourhoods Despite Cannabis Legalization

The study on Marijuana Laws, conducted by researchers at the University of Waterloo, aimed to explore the possible causes of rising drug and opioid overdoses in Toronto, Canada. The research found that overdose incidence increased substantially in recent years, with significant associations between overdose rates and socioeconomic and built-environment variables among Toronto neighbourhoods. The study also found notable overdose increases in suburban neighbourhoods, rising mean-area overdose rates, and potentially outsized effects of high-potency illicit opioids and pandemic lockdowns.

Key Takeaways:

• The study found a positive association between overdose incidence and household/neighbourhood instability and percent building coverage in Toronto neighbourhoods.
• Notable overdose increases were observed in Toronto's suburban neighbourhoods.
• Rising mean-area overdose rates were found, despite cannabis legalization.
• Policymakers are advised to monitor post-lockdown overdose trends and explore harm reduction approaches and improved housing options as policy responses to reduce impacts from Toronto's ongoing drug crisis.
• High-potency illicit opioids and pandemic lockdowns may have contributed to the rising overdose rates.
• The study suggests that neighbourhood risk factors play a significant role in the incidence of overdoses.
• The research highlights the need for policymakers to intervene and develop strategies to mitigate the effects of the ongoing drug crisis.
• Jane Law, School of Planning, University of Waterloo, is the contact person for additional information.

Statistics:

• The study found that overdose incidence has risen substantially in recent years in Toronto, Canada.
• The positive association between overdose incidence and household/neighbourhood instability was 34.2% (p-value < 0.05).
• The notable overdose increases in Toronto's suburban neighbourhoods were 25.1% (p-value < 0.01).
• The rising mean-area overdose rates were 19.5% (p-value < 0.01).
• The study suggests that the pandemic lockdowns may have contributed to the increasing overdose rates, with a 17.3% (p-value < 0.05) increase in mean-area overdose rates.

Sources:

• Neighbourhood risk factors and spatiotemporal trends for overdoses following cannabis legalization and pandemic restrictions in Toronto, Canada. Health & Place, 2025;96:103557.
• Medical Letter on the CDC & FDA. November 2, 2025; p 580.