Identification and quantification of THC and the synthetic cannabinoid MDMB-4en-PINACA in edible products seized by UK police in 2024

Aims: To characterise edible products seized in the United Kingdom (UK) illicit market by (1) analysing packaging designs, (2) quantifying tetrahydrocannabinol (THC) content and identifying other psychoactive substances, including synthetic cannabinoids (SCs), and (3) evaluating a field-portable device for rapid drug identification directly from food products with an illicit substance added (edibles). Design: Laboratory-based chemical analysis of seized drug products and evaluation of a point-of-care diagnostic device. Setting: University analytical laboratories in Bath and Manchester, UK. Participants/Materials: A total of 31 edible products (representing 24 unique items), seized by Merseyside Police and Avon & Somerset Constabulary in the UK during 2024. Measurements: Visual inspection of packaging. Quantification of THC and the SC MDMB-4en-PINACA using validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) with isotopic dilution following homogenisation, liquid-phase extraction, and sample preparation. Evaluation of a portable fluorescence and photochemical degradation-based device for detecting THC and SCs directly on edible surfaces. Findings: Of 24 unique edible products, 19 (79%) used packaging mimicking popular confectionery brands. THC was detected in 28/31 (90.3%) products (70/79 individual edibles). Median THC content per edible was 13.28 mg (range 0–91.18 mg). Of edibles labelled with a THC dose, 95% (65/68) contained significantly less (>45%) than stated. Substantial inter-product variability (e.g., 6.07–29.22 mg THC in edibles labelled as 75 mg) and intra-product variability (dose difference >5 mg THC between items in the same pack for 8/25 packs, max difference 51.91 mg) were found. One product contained MDMB-4en-PINACA (mean 11.42 mg/edible) instead of THC. The portable device demonstrated 94% accuracy (100% on solid sweets/chocolates) in identifying THC/SC content compared to LC-MS/MS. Conclusions: Illicit edibles products seized in the UK use misleading packaging attractive to children, exhibit highly variable and inaccurate THC dosing, and can potentially contain dangerous synthetic cannabinoids like MDMB-4en-PINACA instead of THC, posing significant public health risks. Portable detection technology shows promise for rapid, point-of-care identification to support harm reduction efforts.