Heroin and fentanyl in Dallas County: A 5-year retrospective review of toxicological, seized drug, and demographical data

Research output: Contribution to journalArticlepeer-review


The opioid epidemic resulted in an increase in identifications of fentanyl, fentanyl analogs, and heroin, among other opioids, in the toxicology and seized drug analysis fields over the past several years. The Dallas County Southwestern Institute of Forensic Sciences, comprised of the Toxicology Laboratory and Drug Analysis Laboratory, observed a rise in fentanyl-positive analyses in both laboratories. Fentanyl positivity increased from 1.1% to 3.4% in the Toxicology Laboratory over the five years of this study, whereas 6-monoacetylmorphine (6-MAM) positivity remained relatively stable at approximately 2%. Similarly, in the Drug Analysis Laboratory, the fentanyl positivity rate changed from 0.03% to 0.60%, whereas heroin identification remained stable at approximately 8–9%. Based on data obtained from toxicology submissions, a typical fentanyl or heroin user was a white male in their late 30s. The average concentration of fentanyl in postmortem cases, antemortem cases, and 6-MAM in postmortem specimens was 9.7 ng/ml, 5.5 ng/ml, and 68.4 ng/ml, respectively. Poly-drug use was evident, with benzodiazepines being the most commonly co-administered drug with fentanyl (49.4%). Multiple drugs were identified via analysis of clandestine tablets submitted to the Drug Analysis Laboratory, including fentanyl and/or heroin in combination with compounds such as cocaine, etizolam, and acetaminophen. The most frequently identified clandestine tablet was “M367,” typically manufactured to contain acetaminophen and hydrocodone, but was found to contain fentanyl or heroin. The results from this study aid in the understanding of the current opioid trends in Dallas County and provides an opportunity for comparison to other populations and geographical regions.

Original languageEnglish (US)
Pages (from-to)222-232
Number of pages11
JournalJournal of Forensic Sciences
Issue number1
StatePublished - Jan 2023
Externally publishedYes


  • 6-monoacetylmorphine
  • clandestine tablet
  • fentanyl
  • heroin
  • opioid
  • toxicology

ASJC Scopus subject areas

  • Pathology and Forensic Medicine
  • Genetics


Dive into the research topics of 'Heroin and fentanyl in Dallas County: A 5-year retrospective review of toxicological, seized drug, and demographical data'. Together they form a unique fingerprint.

Cite this