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The Synthetic Opioid ProjectPharmacology, toxicology, and causation — sourced to primary literature.

Every figure in The Synthetic Opioid Project, traced to its source

28 primary sources. Each URL was checked before publication and is rechecked whenever a page in The Synthetic Opioid Project is revised.

The numbered markers throughout the Center overview and the standards link to the matching entry below. Where a source has been superseded or withdrawn, the entry is corrected on the page rather than quietly removed — the editorial policy explains how.

  1. 1.Fentanyl — Drug & Chemical Evaluation (December 2025): pharmacology, control status, 2024 seizure and NFLIS figures. https://www.deadiversion.usdoj.gov/drug_chem_info/fentanyl.pdfU.S. Drug Enforcement Administration, Diversion Control Division
  2. 2.Fentanyl — StatPearls: mu-selective agonist, 50–100x morphine potency, 3–7 hour half-life, repeat naloxone dosing. https://www.ncbi.nlm.nih.gov/books/NBK459275/NCBI Bookshelf, National Library of Medicine
  3. 3.Gill H, Kelly E, Henderson G. How the complex pharmacology of the fentanyls contributes to their lethality. Addiction. 2019;114(9):1524–1525. https://pmc.ncbi.nlm.nih.gov/articles/PMC6767370/Addiction / PubMed Central
  4. 4.Fentanyl — research topic page: 2 mg can be fatal; naloxone may require a second or high-strength dose. https://nida.nih.gov/research-topics/fentanylNational Institute on Drug Abuse (NIH)
  5. 5.Naloxone — StatPearls: 30–80 minute adult half-life; monitor responders 6–12 hours because some opioids outlast naloxone. https://www.ncbi.nlm.nih.gov/books/NBK441910/NCBI Bookshelf, National Library of Medicine
  6. 6.Opioid Toxicity — StatPearls: tolerance to euphoria develops faster than tolerance to respiratory depression; return-to-use risk. https://www.ncbi.nlm.nih.gov/books/NBK470415/NCBI Bookshelf, National Library of Medicine
  7. 7.Xylazine — research topic page: not an opioid; naloxone and nalmefene do not reverse its effects; 276% rise in xylazine-detected fentanyl deaths, Jan 2019–Jun 2022. https://nida.nih.gov/research-topics/xylazineNational Institute on Drug Abuse (NIH)
  8. 8.Sandhu KS, et al. The xylazine-fentanyl nexus: A public health emergency. SAGE Open Medicine. 2025;13:20503121251348068. https://pmc.ncbi.nlm.nih.gov/articles/PMC12179442/SAGE Open Medicine / PubMed Central
  9. 9.Huo S, London K, Murphy L, et al. Notes from the Field: Suspected Medetomidine Withdrawal Syndrome Among Fentanyl-Exposed Patients — Philadelphia, Pennsylvania, September 2024–January 2025. MMWR Morb Mortal Wkly Rep. 2025;74(15):266–268. https://pmc.ncbi.nlm.nih.gov/articles/PMC12045483/CDC Morbidity and Mortality Weekly Report / PubMed Central
  10. 10.Pereira JRP, Quintas A, Neng NR. Nitazenes: The Emergence of a Potent Synthetic Opioid Threat. Molecules. 2025. https://pmc.ncbi.nlm.nih.gov/articles/PMC12526229/Molecules (MDPI) / PubMed Central
  11. 11.Abdelaal GMM, Hegazy NI, Etewa RL, Elmesallamy GEA. Postmortem redistribution of drugs: a literature review. Forensic Sci Med Pathol. 2023;20(4):1483–1490. https://pmc.ncbi.nlm.nih.gov/articles/PMC11790690/Forensic Science, Medicine and Pathology / PubMed Central
  12. 12.Andresen H, Gullans A, Veselinovic M, et al. Fentanyl: toxic or therapeutic? Postmortem and antemortem blood concentrations after transdermal fentanyl application. J Anal Toxicol. 2012;36(3):182–194. https://pubmed.ncbi.nlm.nih.gov/22417834/Journal of Analytical Toxicology / PubMed
  13. 13.Havro V, Casassa N, Andera K, Mata D. A Two-Year Review of Fentanyl in Driving under the Influence and Postmortem Cases in Orange County, CA, USA. J Anal Toxicol. 2022;46(8):875–881. https://pubmed.ncbi.nlm.nih.gov/35639867/Journal of Analytical Toxicology / PubMed
  14. 14.Burrage v. United States, 571 U.S. 204 (2014) — full opinion and syllabus (Scalia, J.); but-for causation holding on the § 841(b)(1)(C) death-results enhancement. https://www.law.cornell.edu/supremecourt/text/12-7515Legal Information Institute, Cornell Law School
  15. 15.United States Reports, Volume 571 — official bound volume containing Burrage v. United States, 571 U.S. 204 (2014). https://www.supremecourt.gov/opinions/boundvolumes/571bv.pdfSupreme Court of the United States
  16. 16.21 U.S.C. § 841 — Prohibited acts A; death-or-serious-bodily-injury enhancement and fentanyl quantity thresholds (400 g / 40 g mixture; 100 g / 10 g analogue). https://uscode.house.gov/view.xhtml?req=granuleid:USC-prelim-title21-section841&num=0&edition=prelimOffice of the Law Revision Counsel, U.S. House of Representatives
  17. 17.Alleyne v. United States, 570 U.S. 99 (2013) — any fact increasing a mandatory minimum is an element for the jury, beyond a reasonable doubt. https://www.law.cornell.edu/supremecourt/text/11-9335Legal Information Institute, Cornell Law School
  18. 18.Federal Rule of Evidence 702, as amended effective December 1, 2023 — preponderance showing to the court and the Rule 702(d) reliable-application requirement. https://www.law.cornell.edu/rules/fre/rule_702Legal Information Institute, Cornell Law School
  19. 19.Two-Thirds of US States Now Have Laws Governing the Prosecution of Drug-Related Deaths as Criminal Killings (January 16, 2025) — 31 states plus D.C. as of May 1, 2024, up 33% from 24 in 2018. https://phlr.temple.edu/news/2025/01/two-thirds-us-states-now-have-laws-governing-prosecution-drug-related-deaths-criminal-killingsCenter for Public Health Law Research, Temple University Beasley School of Law
  20. 20.Drug Induced Homicide Laws — longitudinal 50-state legal dataset (Prescription Drug Abuse Policy System / LawAtlas). https://pdaps.org/datasets/drug-induced-homicide-1529945480-1549313265-1559075032Center for Public Health Law Research, Temple University Beasley School of Law
  21. 21.VSRR Provisional Drug Overdose Death Counts — 12-month-ending national counts by drug category (dataset last updated July 15, 2026; figures cited are the 12 months ending January 2026 and January 2023). https://data.cdc.gov/National-Center-for-Health-Statistics/VSRR-Provisional-Drug-Overdose-Death-Counts/xkb8-kh2aNational Center for Health Statistics, CDC (data.cdc.gov)
  22. 22.Quick Facts: Fentanyl Trafficking, Fiscal Year 2025 (PDF) — 3,605 offenses in FY2025, up 135% since FY2021; average sentence 79 months. https://www.ussc.gov/sites/default/files/pdf/research-and-publications/quick-facts/Fentanyl_FY25.pdfUnited States Sentencing Commission
  23. 23.Quick Facts: Fentanyl Trafficking — publication landing page and series index. https://www.ussc.gov/research/quick-facts/fentanyl-traffickingUnited States Sentencing Commission
  24. 24.MDL Statistics Report — Distribution of Pending MDL Dockets by Actions Pending, report date July 1, 2026 (MDL 2804 National Prescription Opiate Litigation: 2,927 pending / 3,182 historical; MDL 2996 McKinsey: 235 pending). https://www.jpml.uscourts.gov/sites/jpml/files/Pending_MDL_Dockets_By_Actions_Pending-July-1-2026.pdfUnited States Judicial Panel on Multidistrict Litigation
  25. 25.Purdue/Sackler $7.4 Billion National Opioid Settlement Goes into Effect. https://www.attorneygeneral.gov/taking-action/attorney-general-sunday-purdue-sackler-7-4-billion-national-opioid-settlement-goes-into-effect/Pennsylvania Office of Attorney General
  26. 26.New York State Opioid Settlements — company-by-company settlement allocations (Purdue/Sackler, Teva, CVS, Walgreens, Walmart, J&J, distributors, Allergan, Mallinckrodt, Publicis, Endo, McKinsey). https://ag.ny.gov/nys-opioid-settlementOffice of the New York State Attorney General
  27. 27.Becoming a Medical Toxicologist — two-year ACGME-accredited fellowship and ABMS subspecialty certification pathway. https://www.acmt.net/becoming-med-tox/American College of Medical Toxicology
  28. 28.Specialty and Subspecialty Certificates — the recognized ABMS member-board certification structure, including medical toxicology. https://www.abms.org/member-boards/specialty-subspecialty-certificates/American Board of Medical Specialties

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