ABSTRACT
AIMS: To evaluate the long-term trends of new psychoactive substance (NPS) detection in pooled urine samples collected across a city centre. METHODS: Pooled urine samples from portable stand-alone urinals were collected on a monthly basis over 5.5 years (July 2013-December 2018) across a city centre. These were analysed using a high-performance liquid chromatography system, interfaced to a high-resolution accurate mass spectrometer. Data were processed against a database containing over 2000 drugs/metabolites including over 800 NPS. RESULTS: In total, 44 NPS were detected with variation over time including cathinones (15, 34.1%), synthetic cannabinoids (8, 18.2%) and 21 (47.7%) other NPS. Since the introduction of the UK Psychoactive Substances Act (May 2016) cathinone detection has decreased with minimal detection over the last 4 months of the study. Synthetic cannabinoids were not detected on a regular basis until July 2016 with a subsequent variable detection frequency. There was a consistent, low level detection frequency of all other NPS throughout the study, but which appears to have increased alongside the decrease in cathinone detection. CONCLUSION: Pooled urine analysis of samples taken from portable urinals in a city centre can be used as an effective monitoring tool to determine long-term trends in the use of NPS. The results of this study demonstrate the impact of the Psychoactive Substances Act and reflect the findings of population surveys and clinical studies. Triangulation of these data with other data sources will enable greater insight into the NPS phenomenon.
