{"id":22924,"date":"2025-11-25T10:20:08","date_gmt":"2025-11-25T15:20:08","guid":{"rendered":"https:\/\/www.ices.on.ca\/?post_type=journal_article&#038;p=22924"},"modified":"2025-11-28T10:27:06","modified_gmt":"2025-11-28T15:27:06","slug":"effect-of-nonmedical-cannabis-legalization-and-exposure-to-retail-stores-on-cannabis-harms","status":"publish","type":"journal_article","link":"https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/effect-of-nonmedical-cannabis-legalization-and-exposure-to-retail-stores-on-cannabis-harms\/","title":{"rendered":"Effect of nonmedical cannabis legalization and exposure to retail stores on cannabis harms: a quasi-experimental study"},"content":{"rendered":"<p><strong>Background<\/strong> \u2014 In 2018, Canada became the second country to legalize nonmedical cannabis and the first to allow a commercial retail market. Limiting the density of stores selling other legal substances is associated with reductions in use and harms; however, similar associations for cannabis are not well established.<\/p>\n<p><strong>Objective<\/strong> \u2014 To examine the association between exposure to cannabis retail stores and cannabis-related harms.<\/p>\n<p><strong>Design<\/strong> \u2014 Population-based natural experiment examining cannabis-attributable emergency department (ED) visits between 2017 and 2022.<\/p>\n<p><strong>Setting<\/strong> \u2014 Ontario, Canada.<\/p>\n<p><strong>Participants<\/strong> \u2014 10\u2009574 neighborhoods containing 6\u2009140\u2009595 persons aged 15 to 105 years.<\/p>\n<p><strong>Measurements<\/strong> \u2014 The opening of all cannabis stores in Ontario was tracked to identify neighborhoods that became exposed (cannabis store within 1000 m) over time. Absolute and relative changes in rates of cannabis-attributable ED visits were compared in neighborhoods after they became exposed with matched neighborhoods that remained unexposed.<\/p>\n<p><strong>Results<\/strong> \u2014 Cannabis-attributable ED visits were increasing over time before retail store openings. In neighborhoods that became exposed to a cannabis store, the rate of cannabis-attributable ED visits remained constant after stores opened. In contrast, in matched unexposed neighborhoods, the rate of ED visits decreased. Collectively, neighborhoods that were exposed to retail stores had a monthly increase of 1.30 cannabis-attributable ED visits per 100\u2009000 persons (95% CI, 0.51 to 2.09; P\u2009&lt;\u20090.001) compared with unexposed neighborhoods, which was equivalent to a 12% (CI, 6% to 19%) relative increase in the monthly rate of visits.<\/p>\n<p><strong>Limitation<\/strong> \u2014 Findings may be influenced by unmeasured confounding between exposed and unexposed neighborhoods.<\/p>\n<p><strong>Conclusion<\/strong> \u2014 Findings suggest that prohibiting stores in certain areas, limiting store density, or placing restrictions on the overall number of stores may offer public health benefits in countries pursuing legalization.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Background \u2014 In 2018, Canada became the second country to legalize nonmedical cannabis and the first to allow a commercial retail market. Limiting the density of stores selling other legal substances is associated with reductions in use and harms; however, similar associations for cannabis are not well established. Objective \u2014 To examine the association between [&hellip;]<\/p>\n","protected":false},"template":"","migration-helper-automated":[],"migration-manual":[],"topic":[56,60,35],"migration-helper-qa-sample-set":[],"class_list":["post-22924","journal_article","type-journal_article","status-publish","hentry","topic-pharmacoepidemiology-and-drug-safety","topic-policy-and-program-evaluation","topic-public-health"],"acf":{"citation":"Friesen EL, Pugliese M, MacDonald-Spracklin R, Manuel D, Wilson K, Hobin E, Pinto AD, Myran DT. <em>Ann Intern Med<\/em>. 2025; Nov 25 [Epub ahead of print].","source_url":"https:\/\/doi.org\/10.7326\/annals-25-01960","ices_scientist":[1323,17551],"site":[6734],"research_program":[6740],"news_release":"","journal_article":"","atlas":"","research_report":"","infographic":"","video":"","downloads":null,"links":null,"sitecore_item_id":"","sitecore_item_name":"","sitecore_field_values":"","previous_url":""},"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.4 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>ICES | Effect of nonmedical cannabis legalization and exposure to retail stores on cannabis harms: a quasi-experimental study<\/title>\n<meta name=\"description\" content=\"Background \u2014 In 2018, Canada became the second country to legalize nonmedical cannabis and the first to allow a commercial retail market. Limiting the\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/effect-of-nonmedical-cannabis-legalization-and-exposure-to-retail-stores-on-cannabis-harms\/\" \/>\n<meta property=\"og:locale\" content=\"fr_FR\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"ICES | Effect of nonmedical cannabis legalization and exposure to retail stores on cannabis harms: a quasi-experimental study\" \/>\n<meta property=\"og:description\" content=\"Background \u2014 In 2018, Canada became the second country to legalize nonmedical cannabis and the first to allow a commercial retail market. Limiting the\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/effect-of-nonmedical-cannabis-legalization-and-exposure-to-retail-stores-on-cannabis-harms\/\" \/>\n<meta property=\"og:site_name\" content=\"ICES\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/ICESOntario\/\" \/>\n<meta property=\"article:modified_time\" content=\"2025-11-28T15:27:06+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.ices.on.ca\/wp-content\/uploads\/2024\/11\/ic-es-data-discovery-better-health-logo.jpg\" \/>\n\t<meta property=\"og:image:width\" content=\"1200\" \/>\n\t<meta property=\"og:image:height\" content=\"675\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/jpeg\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/publications\\\/journal-articles\\\/effect-of-nonmedical-cannabis-legalization-and-exposure-to-retail-stores-on-cannabis-harms\\\/\",\"url\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/publications\\\/journal-articles\\\/effect-of-nonmedical-cannabis-legalization-and-exposure-to-retail-stores-on-cannabis-harms\\\/\",\"name\":\"ICES | Effect of nonmedical cannabis legalization and exposure to retail stores on cannabis harms: a quasi-experimental study\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/#website\"},\"datePublished\":\"2025-11-25T15:20:08+00:00\",\"dateModified\":\"2025-11-28T15:27:06+00:00\",\"description\":\"Background \u2014 In 2018, Canada became the second country to legalize nonmedical cannabis and the first to allow a commercial retail market. Limiting the\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/publications\\\/journal-articles\\\/effect-of-nonmedical-cannabis-legalization-and-exposure-to-retail-stores-on-cannabis-harms\\\/#breadcrumb\"},\"inLanguage\":\"fr-FR\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/publications\\\/journal-articles\\\/effect-of-nonmedical-cannabis-legalization-and-exposure-to-retail-stores-on-cannabis-harms\\\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/publications\\\/journal-articles\\\/effect-of-nonmedical-cannabis-legalization-and-exposure-to-retail-stores-on-cannabis-harms\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Journal Articles\",\"item\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/publications\\\/journal-articles\\\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"Effect of nonmedical cannabis legalization and exposure to retail stores on cannabis harms: a quasi-experimental study\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/#website\",\"url\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/\",\"name\":\"ICES\",\"description\":\"POPULATION-BASED HEALTH RESEARCH THAT MAKES A DIFFERENCE\",\"publisher\":{\"@id\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/#organization\"},\"alternateName\":\"Institute for Clinical Evaluative Sciences\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"fr-FR\"},{\"@type\":\"Organization\",\"@id\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/#organization\",\"name\":\"ICES\",\"alternateName\":\"Institute for Clinical Evaluative Sciences\",\"url\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"fr-FR\",\"@id\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/#\\\/schema\\\/logo\\\/image\\\/\",\"url\":\"https:\\\/\\\/www.ices.on.ca\\\/wp-content\\\/uploads\\\/2023\\\/04\\\/ices-logo.png\",\"contentUrl\":\"https:\\\/\\\/www.ices.on.ca\\\/wp-content\\\/uploads\\\/2023\\\/04\\\/ices-logo.png\",\"width\":\"676\",\"height\":\"618\",\"caption\":\"ICES\"},\"image\":{\"@id\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/#\\\/schema\\\/logo\\\/image\\\/\"},\"sameAs\":[\"https:\\\/\\\/www.facebook.com\\\/ICESOntario\\\/\",\"https:\\\/\\\/www.linkedin.com\\\/company\\\/ices-research-institute\\\/\"]}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"ICES | Effect of nonmedical cannabis legalization and exposure to retail stores on cannabis harms: a quasi-experimental study","description":"Background \u2014 In 2018, Canada became the second country to legalize nonmedical cannabis and the first to allow a commercial retail market. Limiting the","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/effect-of-nonmedical-cannabis-legalization-and-exposure-to-retail-stores-on-cannabis-harms\/","og_locale":"fr_FR","og_type":"article","og_title":"ICES | Effect of nonmedical cannabis legalization and exposure to retail stores on cannabis harms: a quasi-experimental study","og_description":"Background \u2014 In 2018, Canada became the second country to legalize nonmedical cannabis and the first to allow a commercial retail market. Limiting the","og_url":"https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/effect-of-nonmedical-cannabis-legalization-and-exposure-to-retail-stores-on-cannabis-harms\/","og_site_name":"ICES","article_publisher":"https:\/\/www.facebook.com\/ICESOntario\/","article_modified_time":"2025-11-28T15:27:06+00:00","og_image":[{"width":1200,"height":675,"url":"https:\/\/www.ices.on.ca\/wp-content\/uploads\/2024\/11\/ic-es-data-discovery-better-health-logo.jpg","type":"image\/jpeg"}],"twitter_card":"summary_large_image","schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/effect-of-nonmedical-cannabis-legalization-and-exposure-to-retail-stores-on-cannabis-harms\/","url":"https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/effect-of-nonmedical-cannabis-legalization-and-exposure-to-retail-stores-on-cannabis-harms\/","name":"ICES | Effect of nonmedical cannabis legalization and exposure to retail stores on cannabis harms: a quasi-experimental study","isPartOf":{"@id":"https:\/\/www.ices.on.ca\/fr\/#website"},"datePublished":"2025-11-25T15:20:08+00:00","dateModified":"2025-11-28T15:27:06+00:00","description":"Background \u2014 In 2018, Canada became the second country to legalize nonmedical cannabis and the first to allow a commercial retail market. Limiting the","breadcrumb":{"@id":"https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/effect-of-nonmedical-cannabis-legalization-and-exposure-to-retail-stores-on-cannabis-harms\/#breadcrumb"},"inLanguage":"fr-FR","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/effect-of-nonmedical-cannabis-legalization-and-exposure-to-retail-stores-on-cannabis-harms\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/effect-of-nonmedical-cannabis-legalization-and-exposure-to-retail-stores-on-cannabis-harms\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.ices.on.ca\/fr\/"},{"@type":"ListItem","position":2,"name":"Journal Articles","item":"https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/"},{"@type":"ListItem","position":3,"name":"Effect of nonmedical cannabis legalization and exposure to retail stores on cannabis harms: a quasi-experimental study"}]},{"@type":"WebSite","@id":"https:\/\/www.ices.on.ca\/fr\/#website","url":"https:\/\/www.ices.on.ca\/fr\/","name":"ICES","description":"POPULATION-BASED HEALTH RESEARCH THAT MAKES A DIFFERENCE","publisher":{"@id":"https:\/\/www.ices.on.ca\/fr\/#organization"},"alternateName":"Institute for Clinical Evaluative Sciences","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.ices.on.ca\/fr\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"fr-FR"},{"@type":"Organization","@id":"https:\/\/www.ices.on.ca\/fr\/#organization","name":"ICES","alternateName":"Institute for Clinical Evaluative Sciences","url":"https:\/\/www.ices.on.ca\/fr\/","logo":{"@type":"ImageObject","inLanguage":"fr-FR","@id":"https:\/\/www.ices.on.ca\/fr\/#\/schema\/logo\/image\/","url":"https:\/\/www.ices.on.ca\/wp-content\/uploads\/2023\/04\/ices-logo.png","contentUrl":"https:\/\/www.ices.on.ca\/wp-content\/uploads\/2023\/04\/ices-logo.png","width":"676","height":"618","caption":"ICES"},"image":{"@id":"https:\/\/www.ices.on.ca\/fr\/#\/schema\/logo\/image\/"},"sameAs":["https:\/\/www.facebook.com\/ICESOntario\/","https:\/\/www.linkedin.com\/company\/ices-research-institute\/"]}]}},"_links":{"self":[{"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/journal_article\/22924","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/journal_article"}],"about":[{"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/types\/journal_article"}],"acf:post":[{"embeddable":true,"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/research_program\/6740"},{"embeddable":true,"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/site\/6734"},{"embeddable":true,"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/ices_scientist\/17551"},{"embeddable":true,"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/ices_scientist\/1323"}],"wp:attachment":[{"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/media?parent=22924"}],"wp:term":[{"taxonomy":"migration-helper-automated","embeddable":true,"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/migration-helper-automated?post=22924"},{"taxonomy":"migration-manual","embeddable":true,"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/migration-manual?post=22924"},{"taxonomy":"topic","embeddable":true,"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/topic?post=22924"},{"taxonomy":"migration-helper-qa-sample-set","embeddable":true,"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/migration-helper-qa-sample-set?post=22924"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}