Review of five years of comprehensive NPS analytics and insights into the substance identification workflow of the ADEBAR project

Abstract

The ADEBAR project aims to comprehensively characterize emerging substances relevant for forensic toxicological casework providing collaborative structure elucidation and instrumental analysis services for forensic science institutes in and around Germany. The ADEBAR project addresses the need of the forensic science community for structural elucidation of novel new psychoactive substances (NPS) and other substances appearing on the illicit market and the digital provision of the analytical datasets. High-quality reference substances as well as court-proof analytical data are required to keep screening methods and databases up to date in a timely and cost-efficient manner. The ADEBAR project represents the competence network of the Federal Criminal Police Office, seven State Bureaus of Criminal Investigation, and the German Customs, co-funded by the EU's Internal Security Fund since July 2017. Additionally, the Universities of Mainz and Freiburg have been involved in the anticipatory synthesis and pharmacological assessment of NPS variants since 2019. Forensic institutes, mostly German police and customs laboratories, submit samples to the ADEBAR consortium. New substances emerging on the drug market (seized or purchased) are elucidated and comprehensively characterized using chromatographic, spectroscopic, and spectrometric techniques [GC-MS, (N)-IR, GC-sIR, NMR, LC-(HR)MS, and Raman spectroscopy]. The workflow chart illustrates the sequence of analytical processes within the ADEBAR project. The results of the analytical characterization are documented in a publishable comprehensive report. The report and the corresponding analytical datasets are published digitally through national and international channels (forum of the GTFCh, EDND of the EMCDDA, and NPS Data Hub) and formal reports are submitted to the early warning system (EWS) of the EMCDDA. Over the period of four and a half years, a total of 549 substances have been analytically characterized, leading to close to 400 reports published. Seized materials, test purchases in online shops, and designer drug derivatives synthesized within the ADEBAR project were analyzed. The minimum requirement of the ADEBAR project for an unequivocal identification is applying two analytical techniques of category A (referring to the SWGDRUG classification scheme) to differentiate structurally related isomers reliably. Synthetic cannabinoids were the largest and (designer) pharmaceuticals the second largest group of substances analyzed so far. Identified opioids shifted from fentanyl analogs like cyclopentanoylfentanyl, 3-methylcrotonylfentanyl, and “U-type” compounds (mainly detected in 2017 to 2018) to buccinazine (AP-237, 2-Me-AP-237, and AP-238) and benzimidazole type opioids like isotonitazene, etonitazene, and etonitazepipne from 2019 onwards. In addition, 106 fully characterized and precisely quantified NPS reference substances have been issued to all German forensic institutes together with a certificate of analysis as a continuous service of the ADEBAR project. The ADEBAR project has been contributing to the availability of analytical data and reference material relevant to the daily work of police and customs laboratories. A total of 3619 mass spectra have been published, together with NMR, IR, GC-sIR, and NIR spectra. The datasets were published worldwide and free of charge and facilitate the identification of these new compounds by other forensic laboratories.