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Cited by 19Forensic Toxicology and Drug AnalysisCrime, Illicit Activities, and GovernanceYouth, Drugs, and Violence

Synthetic Illicit Opioids in Brazil: Nitazenes Arrival

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Gonçalves de Araújo, Karen Rafaela, Fabris, André Luis, Junior, Luiz Ferreira Neves, Soares, Alexandre Learth, Costa, Jose Luiz, Yonamine, Mauricio·2024·Forensic Science International Reports
DOI 10.1016/j.fsir.2024.100375
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Abstract

While illicit opioids have not been historically significant in Brazil, these numbers have increased in the last few years. This change in the drug scenario is mainly associated with synthetic opioids, a class of new psychoactive substances (NPS). In this context, the present article describes detailed information about the recent cases of synthetic opioids seized in Brazil, especially the nitazenes group. All the analyses were carried out by the Superintendence of the Technical-Scientific Police - Narcotics Control Center (STSP-NCC) in São Paulo, between July 2022 and April 2023. The synthetic opioids were mainly found in herbal fragments. Nitazenes, were the most frequent drugs detected in the seizures that took place in the State of São Paulo. There was a total of 140 cases of opioids seizures and 95 % out of those belonging to the nitazene group, while only 5 % consisted of other opioids (morphine and fentanyl). Nitazenes were found 28.6 % isolated and 71.4 % mixed with other active compounds, being MDMB-4en-PINACA the most prevalent (30 % of the samples). Non-nitazenes were found 27.1 % mixed and 72.9 % isolated. Nitazenes and non-nitazene opioids were not found in association in any sample. This is the first consistent report of nitazene opioids apprehensions in Brazil. Also, as far as we know, it is the first report in which nitazenes were detected in the form of herbal fragments. The effect of smoking a potent opioid together with synthetic cannabinoids is unpredictable and most users cannot be aware of what they are using.

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  • Nitazenes were detected in 95% of total opioid related state seizures in São Paulo, Brazil, between July 2022 and April 2023.

    “This recent shift in the drug market has also been reported in São Paulo, Brazil, where nitazenes were detected in 95% of total opioid related state seizures between July 2022 and April 2023 [35].”

    From Early identification of the use of potent benzylbenzimidazoles (nitazenes) through wastewater analysis: Two years of data from 22 countries (2025) · cites this paper as [35]

  • Following international scheduling in 2021, a rapid proliferation of other nitazene analogues has emerged worldwide, with dozens reported in toxicology investigations and seized-drug casework.

    “Following its international scheduling in 2021, a rapid proliferation of other nitazene analogues has emerged worldwide, with dozens of different nitazene analogues now reported in both toxicology investigations and seized-drug casework [6,7,8,9].”

    From Nitazenes: The Emergence of a Potent Synthetic Opioid Threat (2025) · cites this paper as [8]

  • The first nitazene widely identified in the recreational drug market was isotonitazene, in 2019, in Europe, Canada, and the United States.

    “The first nitazene to be widely identified in the recreational drug market was isotonitazene, in 2019, in Europe, Canada, and the United States.”

    From Nitazenes: The Emergence of a Potent Synthetic Opioid Threat (2025) · cites this paper as [8]

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Authors
Gonçalves de Araújo, K. R., Fabris, A. L., Junior, L. F. N., Soares, A. L., Costa, J. L., & Yonamine, M.
Venue
Forensic Science International Reports
Publisher
Elsevier BV
Published
2024-12
Volume
10
Pages
100375
ISSN
2665-9107 (ISSN-L)
DOI
10.1016/j.fsir.2024.100375
OpenAlex
W4399753981
Cited by
19
References
16
Citations by year
2026: 8 · 2025: 9 · 2024: 2
FWCI
4.53
Type
journal article
Language
en
Open access
Licence
Locations
  • Forensic Science International Reports (publishedVersion, cc-by-nc-nd)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Funders
  • FAPESP (2021/09857-8)
  • CNPq
  • Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (16/2020)
Topics
  • Life Sciences › Pharmacology, Toxicology and Pharmaceutics › Toxicology › Forensic Toxicology and Drug Analysis
  • Social Sciences › Sociology and Political Science › Crime, Illicit Activities, and Governance
  • Social Sciences › Demography › Youth, Drugs, and Violence
Keywords
synthetic opioids, nitazenes, new psychoactive substances, drug seizures, MDMB-4en-PINACA, synthetic cannabinoids, drug mixing, opioid-related deaths, São Paulo, Brazil

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