Traces of Use: Uncovering Drug Use Insights From Paraphernalia Analysis.

INTRODUCTION: The residue analysis of disposed paraphernalia from people who inject drugs is a novel way to discern drug taking behaviours. This study aimed to investigate the presence of conventional and novel psychoactive substances (NPS) in drug paraphernalia in South Australia. METHODS: Drug paraphernalia were collected in November and December 2024 from sharps disposal bins at three needle and syringe program locations. A total of 300 items of paraphernalia were taken from bins, including syringes, bags, drug storage vials/containers and filters. The items were rinsed with methanol, the solvent filtered and prepared for analysis using a Sciex 6500 + QTrap liquid chromatography tandem mass spectrometry (LC-MS/MS) and detections confirmed using authentic reference materials. RESULTS: A high proportion of paraphernalia contained methamphetamine (61%) and/or heroin (38%). A majority (57%) of the items analysed contained 2 or more drugs. In total, 14 different NPS were detected across 46 items of paraphernalia. DISCUSSION AND CONCLUSIONS: The large number of paraphernalia items that had multiple drugs detected was likely an indication of polysubstance use. Residue analysis of drug paraphernalia is an objective approach to complement those currently used to ascertain drug trends, which strengthens harm reduction and public health responses to drug use. This study shows that drug residue analysis is feasible, non-invasive and effective, providing a near-real time approach to monitor the appearance of high potency NPS and other drugs being consumed, and determining trends in conventional substance use by people who inject drugs.