{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T12:26:51Z","timestamp":1776169611145,"version":"3.50.1"},"reference-count":54,"publisher":"Public Library of Science (PLoS)","issue":"5","license":[{"start":{"date-parts":[[2025,5,23]],"date-time":"2025-05-23T00:00:00Z","timestamp":1747958400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the Public Health Agency of Canada, Substance-Related Harms Division, and grants from the Canadian Institutes of Health Research","award":["#153070"],"award-info":[{"award-number":["#153070"]}]},{"name":"the Public Health Agency of Canada, Substance-Related Harms Division, and grants from the Canadian Institutes of Health Research","award":["#178163"],"award-info":[{"award-number":["#178163"]}]},{"name":"the Network for Improving Health Systems Trainee Award"},{"name":"Banting postdoctoral fellowship from the Canadian Institutes of Health Research."},{"name":"Tier 2 Canada Research Chair"},{"name":"Ontario Ministry of Health, Canada\u2019s Drug Agency, and Indigenous Services Canada"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:sec id=\"sec017\">\n<jats:title>Objective<\/jats:title>\n<jats:p>To investigate trends and the circumstances surrounding fatal substance-related toxicities directly attributed to alcohol, stimulants, benzodiazepines or opioids and combinations of substances in Ontario, Canada.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec018\">\n<jats:title>Methods<\/jats:title>\n<jats:p>We conducted a population-based cross-sectional study of all accidental substance-related toxicity deaths in Ontario, Canada from January 1, 2018 to June 30, 2022. We reported monthly rates of substance-related toxicity deaths and investigated the combination of substances most commonly involved in deaths. Demographic characteristics, location of incident, and prior healthcare encounters for non-fatal toxicities and substance use disorders were examined.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec019\">\n<jats:title>Results<\/jats:title>\n<jats:p>Overall, 10,022 accidental substance-related toxicity deaths occurred, with the annual number of deaths nearly doubling between the first and last 12 months of the study period (N\u2009=\u20091,570\u20132,702). Opioids were directly involved in the majority of deaths (84.1%; N\u2009=\u20098,431), followed by stimulants (60.9%; N\u2009=\u20096,108), alcohol (13.4%; N\u2009=\u20091,346) and benzodiazepines (7.8%; N\u2009=\u2009782). In total, 56.9% (N\u2009=\u20095,698) of deaths involved combinations of substances. Approximately one-fifth of individuals were treated in a hospital setting for a substance-related toxicity in the past year, with the majority being opioid-related (17.4%; N\u2009=\u20091,748). Finally, 60.9% (N\u2009=\u20096,098) of people had a substance use disorder diagnosis at time of death.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec020\">\n<jats:title>Conclusions<\/jats:title>\n<jats:p>Our study shows not only the enormous loss of life from substance-related toxicities but also the growing importance of combinations of substances in these deaths. A large proportion of people had previously interacted within an hospital setting for prior substance-related toxicity events or related to a substance use disorder, representing important missed intervention points in providing appropriate care.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pone.0324732","type":"journal-article","created":{"date-parts":[[2025,5,23]],"date-time":"2025-05-23T17:54:38Z","timestamp":1748022878000},"page":"e0324732","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":4,"title":["The changing role of substances: trends, characteristics of individuals and prior healthcare utilization among individuals with accidental substance-related toxicity deaths in Ontario 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