High variation in purity of consumer-level illicit fentanyl samples in Los Angeles, September 2023–April 2025

IF 4.4 2区医学 Q1 SUBSTANCE ABUSE

International Journal of Drug Policy Pub Date : 2025-08-30 DOI:10.1016/j.drugpo.2025.104977

Chelsea L. Shover , Adam J. Koncsol , Morgan E. Godvin , David Goodman-Meza , Bryce Pardo , Michelle Poimboeuf , Caitlin A. Molina , Ruby Romero , Jasmine Feng , Joseph R. Friedman

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引用次数: 0

Abstract

Background

The illicit manufacture of fentanyl results in product of unknown purity, contributing to overdose risk. However, data on the purity of illicitly manufactured fentanyl (IMF) in the United States typically comes from law enforcement sources and almost no information relevant to retail-level product is made available. We aim to quantify IMF purity among samples from a community-based drug checking program operating at four geographic sites in Los Angeles, California.

Methods

Drug samples (n = 1763) were obtained from participants who also answered an anonymous survey about sample characteristics. Qualitative and quantitative analysis were conducted leveraging directly observed mass spectrometry (DART-MS) and liquid chromatography mass spectrometry (LC/MS) respectively. LC/MS quantified a panel of compounds including fentanyl and fluorofentanyl. Composite IMF purity was estimated by adding the percent mass of fentanyl and fluorofentanyl.

Results

A total of 353 samples had either fentanyl, fluorofentanyl, or both quantified between September 2023 and April 2025. Median IMF purity was 5.8 %, mean 10.0 %, SD 11.1 %, range 0.1–64.9 %. Samples expected to be fentanyl (n = 308) had higher median purity (7.0 %) compared to those expected to be heroin (n = 24, median purity 1.4 %) or other drugs (p < 0.001). Powder samples (n = 318) had higher median concentration (6.9 %) compared to pills (n = 11, 0.7 %) or tar (n = 22, 1.4 %) [p < 0.001]. Of expected-fentanyl samples, 42.5 % (n = 131) had an IMF purity of <5 %, while 17.5 % (n = 54) had purity over 20 %.

Conclusions

We found high variation in IMF purity among samples sold as fentanyl, even among samples obtained on the same day, in the same location. This volatility likely plays a role in high overdose risk, even among people with opioid tolerance, in the fentanyl era. Further research is needed to compare these findings to other locations across the United States.

查看原文本刊更多论文

2023年9月至2025年4月，洛杉矶消费级非法芬太尼样品纯度差异很大

非法制造芬太尼会产生纯度未知的产品，增加过量的风险。然而，关于美国非法制造芬太尼纯度的数据通常来自执法部门，几乎没有提供与零售级产品有关的信息。我们的目标是量化来自加利福尼亚州洛杉矶四个地理站点的社区药物检查项目样本中的IMF纯度。方法从参与者中抽取药物样本（n = 1763），并对样本特征进行匿名调查。分别利用直接观察质谱法（DART-MS）和液相色谱质谱法（LC/MS）进行定性和定量分析。LC/MS定量了一组化合物，包括芬太尼和氟芬太尼。通过加入芬太尼和氟芬太尼的质量百分比来估计复合IMF的纯度。结果2023年9月至2025年4月，共有353份样品中芬太尼、氟芬太尼或两者兼有。IMF纯度中位数为5.8%，平均值为10.0%，SD为11.1%，范围为0.1 ~ 64.9%。预期为芬太尼的样品（n = 308）的中位纯度（7.0%）高于预期为海洛因（n = 24，中位纯度1.4%）或其他药物（p < 0.001）。粉末样品（n = 318）的中位浓度（6.9%）高于丸剂（n = 11,0.7 %）或焦油（n = 22,1.4 %） [p < 0.001]。在预期芬太尼样品中，42.5% （n = 131）的IMF纯度为5%，17.5% （n = 54）的纯度超过20%。结论：在芬太尼样品中，即使在同一天、同一地点获得的样品中，IMF的纯度也存在很大差异。在芬太尼时代，这种波动性可能在高过量风险中发挥作用，即使在阿片类药物耐受性的人群中也是如此。需要进一步的研究将这些发现与美国其他地区进行比较。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

International Journal of Drug Policy SUBSTANCE ABUSE-

CiteScore

7.80

自引率

11.40%

发文量

307

审稿时长

62 days

期刊介绍： The International Journal of Drug Policy provides a forum for the dissemination of current research, reviews, debate, and critical analysis on drug use and drug policy in a global context. It seeks to publish material on the social, political, legal, and health contexts of psychoactive substance use, both licit and illicit. The journal is particularly concerned to explore the effects of drug policy and practice on drug-using behaviour and its health and social consequences. It is the policy of the journal to represent a wide range of material on drug-related matters from around the world.