Skip to main content

Potential harms from legalization of recreational cannabis use in Canada


With the recent legalization of recreational cannabis use in Canada, questions remain concerning optimal regulation to minimize harms and ensure public health and safety. Patterns of use are subject to change following legalization, and it is important to consider the potential adverse effects that this may have on public health. Important areas of consideration are methods of consumption (e.g., vaping, edibles) and product proliferation; acute and long-term health and behavioural effects (including impaired driving); and use in vulnerable groups, such as children and youth, pregnant women, individuals with mental illness, individuals with low socio-economic status, and Indigenous populations. To support harm reduction measures and evidence-based policy, there is a need to anticipate the potential ramifications that legalization of recreational cannabis use may have on public health in Canada.


L’usage récréatif du cannabis a été légalisé récemment au Canada, mais des questions demeurent sur la réglementation optimale pour réduire les préjudices et assurer la santé et la sécurité du public. Comme les tendances de consommation pourraient changer après la légalisation, il importe de tenir compte des éventuels effets indésirables que cela pourrait avoir sur la santé publique. Il faudra notamment considérer les méthodes de consommation (p. ex. vapotage, ingestion) et la prolifération des produits; les effets immédiats et à long terme sur la santé et les comportements (dont la conduite avec facultés affaiblies); ainsi que la consommation dans les groupes vulnérables comme les enfants et les jeunes, les femmes enceintes, les personnes atteintes de maladies mentales, les personnes de faible statut socioéconomique et les populations autochtones. Pour soutenir les mesures de réduction des méfaits et l’élaboration de politiques fondées sur les données probantes, il est nécessaire de prévoir les ramifications possibles de la légalisation de l’usage récréatif du cannabis sur la santé publique au Canada.

This is a preview of subscription content, access via your institution.


  • Ashton, C. H. (2001). Pharmacology and effects of cannabis: a brief review. The British Journal of Psychiatry : the Journal of Mental Science, 178, 101–106.

    CAS  Article  Google Scholar 

  • Carliner, H., Brown, Q. L., Sarvet, A. L., & Hasin, D. S. (2017). Cannabis use, attitudes, and legal status in the U.S.: a review. Preventive Medicine.

  • Colorado Department of Public Health & Environment. (2016). Monitoring Health Concerns Related to Marijuana in Colorado: 2016. Accessed July 31, 2017 from:

  • Degenhardt, L., Ferrari, A. J., Calabria, B., Hall, W. D., Norman, R. E., McGrath, J., et al. (2013). The global epidemiology and contribution of cannabis use and dependence to the global burden of disease: results from the GBD 2010 study. PLoS One, 8(10), e76635.

    CAS  Article  Google Scholar 

  • Dickson, B., Mansfield, C., Guiahi, M., Allshouse, A. A., Borgelt, L. M., Sheeder, J., et al. (2018). Recommendations from cannabis dispensaries about first-trimester cannabis use. Obstetrics and Gynecology, 131(6), 1031–1038.

    Article  Google Scholar 

  • Fergusson, D. M., Horwood, L. J., & Swain-Campbell, N. (2002). Cannabis use and psychosocial adjustment in adolescence and young adulthood. Addiction, 97(9), 1123–1135.

    Article  Google Scholar 

  • First Nations Information Governance Centre. (2010). Regional Health Survey 2008/10. Retrieved August 14, 2017 from:

  • Foulds, J., Veldheer, S., & Berg, A. (2011). Electronic cigarettes (e-cigs): views of aficionados and clinical/public health perspectives. International Journal of Clinical Practice, 65(10), 1037–1042.

    CAS  Article  Google Scholar 

  • Hall, W., & Degenhardt, L. (2009). Adverse health effects of non-medical cannabis use. Lancet, 374(9698), 1383–1391.

    CAS  Article  Google Scholar 

  • Hall, W., & Solowij, N. (1998). Adverse effects of cannabis. Lancet, 352(9140), 1611–1616.

    CAS  Article  Google Scholar 

  • Hartman, R. L., & Huestis, M. A. (2013). Cannabis effects on driving skills. Clinical Chemistry, 59(3), 478–492.

    CAS  Article  Google Scholar 

  • Investing News Network. (2017). Health Canada Gets New Funding for Cannabis Campaign. Retrieved March 23, 2018 from:

  • Khalsa, J. H., Genser, S., Francis, H., & Martin, B. (2002). Clinical consequences of marijuana. Journal of Clinical Pharmacology, 42(11 Suppl), 7s–10s.

    CAS  Article  Google Scholar 

  • Lev-Ran, S., Le Foll, B., McKenzie, K., George, T. P., & Rehm, J. (2013). Cannabis use and cannabis use disorders among individuals with mental illness. Comprehensive Psychiatry, 54(6), 589–598.

    Article  Google Scholar 

  • Meier, M. H., Caspi, A., Ambler, A., Harrington, H., Houts, R., Keefe, R. S., et al. (2012). Persistent cannabis users show neuropsychological decline from childhood to midlife. Proceedings of the National Academy of Sciences of the United States of America, 109(40), E2657–E2664.

    CAS  Article  Google Scholar 

  • Metz, T. D., & Stickrath, E. H. (2015). Marijuana use in pregnancy and lactation: a review of the evidence. American Journal of Obstetrics and Gynecology, 213(6), 761–778.

    Article  Google Scholar 

  • Moir, D., Rickert, W. S., Levasseur, G., Larose, Y., Maertens, R., White, P., et al. (2008). A comparison of mainstream and sidestream marijuana and tobacco cigarette smoke produced under two machine smoking conditions. Chemical Research in Toxicology, 21(2), 494–502.

    CAS  Article  Google Scholar 

  • National Academies of Sciences, Engineering, and Medicine. (2017). The health effects of cannabis and cannabinoids: The current state of evidence and recommendations for research. Washington, DC: The National Academies Press.

    Book  Google Scholar 

  • O'Connor, M. (2018). Medicinal cannabis in pregnancy - panacea or noxious weed? Journal of Law and Medicine, 25(3), 634–646.

    PubMed  Google Scholar 

  • O'Kane, C. J., Tutt, D. C., & Bauer, L. A. (2002). Cannabis and driving: a new perspective. Emergency Medicine (Fremantle, WA), 14(3), 296–303.

    Article  Google Scholar 

  • Ramaekers, J. G., Berghaus, G., van Laar, M., & Drummer, O. H. (2004). Dose related risk of motor vehicle crashes after cannabis use. Drug and Alcohol Dependence, 73(2), 109–119.

    CAS  Article  Google Scholar 

  • Schauer, G. L., King, B. A., Bunnell, R. E., Promoff, G., & McAfee, T. A. (2016). Toking, vaping, and eating for health or fun: marijuana use patterns in adults, U.S, 2014. American Journal of Preventive Medicine, 50(1), 1–8.

    Article  Google Scholar 

  • Statistics Canada. (2018). National Cannabis Survey, first quarter 2018. Retrieved October 29, 2018 from:

  • Substance Abuse and Mental Health Services Administration. (2016). Comparison of 2008–2009 and 2015–2016 NSDUH State Prevalence Estimates. Retrieved October 29, 2018 from:

  • The Society of Obstetricians and Gynaecologists of Canada (SOGC). (2018). The SOGC Urges Canadians to Avoid Cannabis Use During Pregnancy and Breastfeeding. Retrieved April 30, 2018 from:

  • United Nations Office on Drugs and Crime. (2006). Review of the world cannabis situation. Bulletin on Narcotics; LVIII (1–2).

Download references

Author information

Authors and Affiliations


Corresponding author

Correspondence to Mark J. Eisenberg.

Additional information

Publisher’s note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Windle, S.B., Wade, K., Filion, K.B. et al. Potential harms from legalization of recreational cannabis use in Canada. Can J Public Health 110, 222–226 (2019).

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI:


  • Cannabis
  • Health legislation
  • Public health
  • Vulnerable populations


  • Cannabis
  • Législation sanitaire
  • Santé publique
  • Populations vulnérables