Chiron (Norway)

Per- and polyfluoroalkyl substances (PFAS) form a large chemical group, but routine monitoring targets only a few well-known compounds such as perfluorooctane sulfonic acid (PFOS). To better understand the widespread occurrence of PFAS in Dutch surface waters, we performed target analysis using an expanded list of compounds, combined with extensive suspect and de novo non-target screening (SNTS) to explore unreported PFAS beyond the scope of conventional monitoring. Analyses were performed using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and liquid chromatography-trapped ion-mobility time-of-flight mass spectrometry (LC-timsTOF-MS). Target analysis focused on 24 previously underreported sulfonamide-based PFASs, enabled by newly available analytical standards and 34 common PFASs, representing 58 compounds. Several N-alkyl perfluoroalkane sulfonamidoacetic acids, including MeFBSAA (up to 50ng/L), were found. SPr-FHxSA (N-sulfo propyl perfluorohexane sulfonamide), associated with aqueous film-forming foams (AFFFs), was detected in five samples (0.14-1.99ng/L). In total, 38 PFAS were identified by target analysis. Collision cross-section (CCS) values of analytical standards were measured prior to SNTS. In SNTS, nineteen compounds, mainly fluorinated pharmaceuticals and pesticides, were identified at confidence level 2a using the MassBank library. Another 22 candidates were tentatively classified at levels 2b or 3, including an unsaturated PFOS analogue and a fluazinam transformation product, highlighting the ability of de novo SNTS to uncover unexpected PFAS. Finally, 6:2 fluorotelomer sulfonyl propanoamido-dimethylethyl sulfonate (6:2 FtSO2AoS) was confirmed at level 1a. Overall, integrating new PFAS standards with SNTS provided a far more complete view of PFAS presence in Dutch waters than target monitoring.

Chlorinated paraffins (CPs) are emerging environmental contaminants with limited biotransformation data because of the complexity of CP technical mixtures and the lack of single congener standards. In this study, novel single CP congeners, with similar chlorine patterns to those found in technical mixtures, were incubated for 60 min with rat hepatic subcellular fractions to evaluate their relative biotransformation extent and identify their potential metabolites. Results demonstrated that these CP congeners were metabolized by phenobarbital and 5,6-benzoflavone-induced rat liver S9, following 1st-order kinetics. The 1st-order rate constants were logarithmically inversely related to the chain lengths at a given number of chlorine atoms. In turn, the chlorine positions affected the biotransformation pathways, resulting in the formation of different metabolites. Metabolites identified by high-resolution mass spectrometric analysis included (multi-)hydroxylated, carbonyl, carboxylic, and chain-shortened products. Hydrolytic and oxidative dechlorination, stepwise hydroxylation/oxidation, and C-C bond cleavage were identified as potential biotransformation pathways. A notable transformation of initial hydroxylated metabolites further into aldehydes and carboxylic acids (ω-oxidation) was emphasized. The study's results fill the knowledge gap in CP biotransformation and provide structural information on potentially bioactive CP metabolites for future synthesis and toxicity studies.

Perfluorooctane sulfonamide derivatives have been extensively used by industry for their surfactant properties and as building blocks for other perfluoroalkyl substances (PFAS). Due to their environmental impact and their potential degradation to other harmful PFAS, short-chain sulfonamide derivatives alternatives were introduced. However, these are now also suspected to be present in different environmental matrices and there is a lack of labelled and unlabelled reference standards to perform analyses. To address this gap, 40 native and deuterium labelled short-chain perfluoroalkane sulfonamide derivatives were synthesized, utilizing commercial perfluoroalkane sulfonyl fluoride as starting materials. All products were synthesized and then purified to obtain linear n-isomer reference standards. NMR, GC-FID-MS and LC-MS techniques were used for product identification and purity assessment. Recrystallization method was developed to selectively isolate the n-isomer from the isomer mixtures, thereby providing valuable reference and internal standards for environmental and toxicological investigations.

The emergence of new synthetic cannabinoid receptor agonists (SCRAs) onto the illicit drugs market continues to cause harm, and the overall availability of physicochemical and pharmacokinetic data for new psychoactive substances is lacking. The lipophilicity of 23 SCRAs and the plasma protein binding (PPB) of 11 SCRAs was determined. Lipophilicity was determined using a validated chromatographic hydrophobicity index (CHI) log D method; tested SCRAs showed moderate to high lipophilicity, with experimental log D7.4 ranging from 2.48 (AB-FUBINACA) to 4.95 (4F-ABUTINACA). These results were also compared to in silico predictions generated using seven commercially available software packages and online tools (Canvas; ChemDraw; Gastroplus; MoKa; PreADMET; SwissADME; and XlogP). Licenced, dedicated software packages provided more accurate lipophilicity predictions than those which were free or had prediction as a secondary function; however, the latter still provided competitive estimates in most cases. PPB of tested SCRAs, as determined by equilibrium dialysis, was in the upper range of the lipophilicity scale, ranging from 90.8% (ADB-BUTINACA) to 99.9% (BZO-HEXOXIZID). The high PPB of these drugs may contribute to reduced rate of clearance and extended durations of pharmacological effects compared to lesser-bound SCRAs. The presented data improve understanding of the behaviour of these drugs in the body. Ultimately, similar data and predictions may be used in the prediction of the structure and properties of drugs yet to emerge on the illicit market.

Reference materials (RMs) are vital tools in the validation of methods used to detect environmental pollutants. Microplastics, a relatively new environmental pollutant, require a variety of complex approaches to address their presence in environmental samples. Both interlaboratory comparison (ILC) studies and RMs are essential to support the validation of methods used in microplastic analysis. Presented here are results of quality assurance and quality control (QA/QC) performed on two types of candidate microplastic RMs: dissolvable gelatin capsules and soda tablets. These RMs have been used to support numerous international ILC studies in recent years (2019–2022). Dissolvable capsules containing polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyethylene (PE), and polystyrene (PS), in different size fractions from 50 to 1000 µm, were produced for one ILC study, obtaining relative standard deviation (RSD) from 0 to 24%. The larger size fraction allowed for manual addition of particles to the capsules, yielding 0% error and 100% recovery during QA/QC. Dissolvable capsules were replaced by soda tablets in subsequent ILC studies and recovery test exercises because they were found to be a more reliable carrier for microplastic RMs. Batches of soda tablets were produced containing different single and multiple polymer mixtures, i.e., PE, PET, PS, PVC, polypropylene (PP), and polycarbonate (PC), with RSD ranging from 8 to 21%. Lastly, soda tablets consisting of a mixture of PE, PVC, and PS (125–355 µm) were produced and used for recovery testing during pretreatment of environmental samples. These had an RSD of 9%. Results showed that soda tablets and capsules containing microplastics >50 µm could be produced with sufficient precision for internal recovery tests and external ILC studies. Further work is required to optimize this method for smaller microplastics (< 50 µm) because variation was found to be too large during QA/QC. Nevertheless, this approach represents a valuable solution addressing many of the challenges associated with validating microplastic analytical methods.

Clarification of the Correct Nomenclature of the Amino Metabolite of Clonazolam: 8-Aminoclonazolam Peter D Maskell, Peter D Maskell Forensic Medicine and Science, University of Glasgow, Glasgow G12 8QQ, UK *Author to whom correspondence should be addressed. Email: peter.maskell@glasgow.ac.uk https://orcid.org/0000-0003-3801-9658 Search for other works by this author on: Oxford Academic PubMed Google Scholar Claire Parks, Claire Parks Forensic Medicine and Science, University of Glasgow, Glasgow G12 8QQ, UK Search for other works by this author on: Oxford Academic PubMed Google Scholar Jenny Button, Jenny Button Chiron AS, Stiklestadveien 1, 7041 Trondheim, Norway Search for other works by this author on: Oxford Academic PubMed Google Scholar Huiling Liu, Huiling Liu Chiron AS, Stiklestadveien 1, 7041 Trondheim, Norway Search for other works by this author on: Oxford Academic PubMed Google Scholar Denise A McKeown Denise A McKeown Forensic Medicine and Science, University of Glasgow, Glasgow G12 8QQ, UK Search for other works by this author on: Oxford Academic PubMed Google Scholar Journal of Analytical Toxicology, Volume 45, Issue 2, March 2021, Pages e1–e2, https://doi.org/10.1093/jat/bkaa169 Published: 04 November 2020 Article history Received: 29 September 2020 Revision received: 16 October 2020 Editorial decision: 19 October 2020 Accepted: 26 October 2020 Published: 04 November 2020

Synthetic cannabinoid receptor agonists (SCRAs) are one of the largest groups of new psychoactive substances monitored in Europe. SCRAs are known to typically exert higher cannabinoid activity than tetrahydrocannabinol from cannabis, thereby entailing a greater health risk. Both Cumyl-PEGACLONE and 5F-Cumyl-PEGACLONE were not controlled by the national legislation upon their first detection in Germany in 2016 and 2017, respectively, and have been linked to several fatalities. In this study, the CB1 receptor activity of these compounds, together with two newly synthesized structural isomers (Cumyl-PEGACLONE ethylbenzyl isomer and n-propylphenyl isomer), was assessed using two different in vitro receptor-proximal bioassays, monitoring the recruitment of either β-arrestin2 (β-arr2) or a modified G protein (mini-Gαi ) to the activated CB1 receptor. In terms of both potency and relative efficacy, Cumyl-PEGACLONE and 5F-Cumyl-PEGACLONE were found to exert strong CB1 activation, with sub-nanomolar EC50 values and efficacy values exceeding those of the reference agonist JWH-018 threefold (β-arr2 assay) or almost twofold (mini-Gαi assay). The ethylbenzyl and n-propylphenyl isomers exhibited a strongly reduced CB1 activity (EC50 values >100 nM; efficacy <40% relative to JWH-018), which is hypothesized to originate from steric hindrance in the ligand-binding pocket. None of the evaluated compounds exhibited significant biased agonism. In conclusion, the functional assays applied here allowed us to demonstrate that 5-fluorination of Cumyl-PEGACLONE is not linked to an intrinsically higher CB1 activation potential and that the ethylbenzyl and n-propylphenyl isomers yield a strongly reduced CB1 activation.

(−)-∆9-Tetrahydrocannabinol is the principal psychoactive component of the cannabis plant and also the active ingredient in some prescribed drugs. To detect and control misuse and monitor administration in clinical settings, reference samples of the native drugs and their metabolites are needed. The accuracy of liquid chromatography/mass spectrometric quantification of drugs in biological samples depends among others on ion suppressing/alteration effects. Especially, 13C-labeled drug analogues are useful for minimzing such interferences. Thus, to provide internal standards for more accurate quantification and for identification purpose, synthesis of [13C4]-∆9-tetrahydro-cannabinol and [13C4]-11-nor-9-carboxy-∆9-tetrahydrocannabinol was developed via [13C4]-olivetol. Starting from [13C4]-olivetol the synthesis of [13C4]-11-nor-9-carboxy-∆9-tetrahydrocannabinol was shortened from three to two steps by employing nitromethane as a co-solvent in condensation with (+)-apoverbenone.