{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T03:16:59Z","timestamp":1792725419563,"version":"4.5.0"},"reference-count":30,"publisher":"Springer Science and Business Media LLC","issue":"3","license":[{"start":{"date-parts":[[2025,2,24]],"date-time":"2025-02-24T00:00:00Z","timestamp":1740355200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2025,2,24]],"date-time":"2025-02-24T00:00:00Z","timestamp":1740355200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/100000026","name":"National Institute on Drug Abuse","doi-asserted-by":"publisher","award":["R01DA052381"],"award-info":[{"award-number":["R01DA052381"]}],"id":[{"id":"10.13039\/100000026","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Can J Public Health"],"published-print":{"date-parts":[[2025,6]]},"abstract":"<jats:title>Abstract<\/jats:title>\n          <jats:sec>\n            <jats:title>Objective<\/jats:title>\n            <jats:p>In recent years, Canada\u2019s unregulated drug supply has become permeated by novel adulterants (e.g., fentanyl analogues, benzodiazepines, xylazine). While fentanyl has been shown to be associated with overdose mortality and other non-fatal health outcomes, adverse events (AE) associated with these adulterants remain poorly described. This study seeks to identify whether common adulterants identified through drug checking services are associated with increased prevalence of specific adverse events reportedly experienced by people who use drugs.<\/jats:p>\n          <\/jats:sec>\n          <jats:sec>\n            <jats:title>Methods<\/jats:title>\n            <jats:p>Drug checking samples were analyzed using Fourier-transform infrared spectroscopy and immunoassay strips at harm reduction sites in British Columbia. Self-reported AE (e.g., non-fatal overdose, prolonged sedation, seizures) were recorded from individuals who checked opioids post-consumption. Adjusted prevalence ratios (aPR) and 95% confidence intervals (95% CI) of AE among common adulterants were calculated using generalized linear models with a Poisson distribution, controlled for presence of other adulterants, expected drug, geographic location, and month.<\/jats:p>\n          <\/jats:sec>\n          <jats:sec>\n            <jats:title>Results<\/jats:title>\n            <jats:p>Between February 2022 and May 2024, 80,415 samples were analyzed at community sites. Among eligible samples, 36.1% were expected opioids, 42.2% of which were checked post-consumption. AE were noted among 10.7% of post-consumption opioid drug checks. After adjustment, the presence of benzodiazepines in opioid samples was associated with increased prevalence of any AE (aPR 1.97; 95% CI 1.70\u20132.27), as was the presence of xylazine (aPR 1.50; 95% CI 1.09\u20132.07). Considering specific AE, benzodiazepines were associated with increased prevalence of overdose (aPR 2.05; 95% CI 1.68\u20132.51) and prolonged sedation (aPR 3.35; 95% CI 2.54\u20134.43).<\/jats:p>\n          <\/jats:sec>\n          <jats:sec>\n            <jats:title>Conclusion<\/jats:title>\n            <jats:p>Non-fatal AE associated with unregulated opioids have been largely undescribed. Our findings report specific AE associated with different adulterants in the unregulated opioid supply. With this information, tailored public health interventions and services focused on these adulterants can be developed.<\/jats:p>\n          <\/jats:sec>","DOI":"10.17269\/s41997-024-00990-7","type":"journal-article","created":{"date-parts":[[2025,2,24]],"date-time":"2025-02-24T12:27:18Z","timestamp":1740400038000},"page":"356-363","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Novel adulterants in unregulated opioids and their associations with adverse events"],"prefix":"10.17269","volume":"116","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6051-8950","authenticated-orcid":false,"given":"Samuel","family":"Tobias","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jennifer","family":"Angelucci","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9412-6699","authenticated-orcid":false,"given":"Evan","family":"Wood","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2295-393X","authenticated-orcid":false,"given":"Jane A.","family":"Buxton","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2470-438X","authenticated-orcid":false,"given":"Lianping","family":"Ti","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2025,2,24]]},"reference":[{"key":"990_CR1","doi-asserted-by":"publisher","DOI":"10.1007\/978-3-642-04898-2_110","volume-title":"International Encyclopedia of Statistical Science","author":"H Akaike","year":"2011","unstructured":"Akaike, H. 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He is also a professor of medicine based at the University of British Columbia (UBC), a position supported by a Canadian Institutes of Health Research (CIHR) Tier 1 Canada Research Chair, and has received salary support from an R01 from the US National Institute on Drug Abuse, paid to UBC. Wood\u2019s research lab is further supported by CIHR grants to the Canadian Research Initiative in Substance Misuse. Wood has also undertaken consulting work in legal matters related to substance use disorders and formerly for a mental health company called Numinus Wellness, where he was previously the chief medical officer; he has also received compensation in the form of equity in Numinus. Wood reports receiving honoraria for non-industry-related academic lectures and conference presentations. He has also received payment for expert reports and expert testimony in legal matters pertaining to substance use disorder, including from the Canadian Medical Protective Association and from trade unions representing workers with possible substance use disorder. Wood has received travel support from CIHR. All other authors declare no conflicts of interest.","order":5,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflict of interest"}}]}}