Thomas P. Knepper

The established approaches of suspect and nontarget screening (NTS) using liquid chromatography–high‐resolution mass spectrometry (LC‐HRMS) are usually applied in the field of environmental and bioanalytical analysis. Herein, these approaches were employed on a forensic‐toxicological application by analyzing different production waste samples from controlled amphetamine synthesis via Leuckart route to evaluate the suitability of this methodology for identification of route‐specific organic substances in such waste samples. For analysis, two complementary LC techniques were used to cover a broad polarity spectrum. After data processing and peak picking using the enviMass software and further manual data restriction, 17 features were tentatively identified as suspects, three of which were subsequently identified with reference substances. All suspects had been previously identified in studies, in which gas chromatography–mass spectrometry (GC‐MS) was successfully applied for synthesis marker assessment in waste and amphetamine samples. Remaining features with high signal intensity and assigned sum formula were selected for the attempt of structure elucidation. Seven potential synthesis markers were tentatively identified, which were not yet reported, except the sum formula of one compound, and which were partly also detected in real case waste samples afterward. The innovative application of the NTS approach using LC‐HRMS for the analysis of aqueous amphetamine synthesis waste samples showed its suitability as extension to GC‐MS analysis as it was possible to successfully identify seven new potential marker compounds, which are specific either for the conversion of the pre‐precursors α‐phenylacetoacetonitrile and α‐phenylacetoacetamide to benzyl methyl ketone or for the subsequent Leuckart synthesis route after their conversion.

Since their first appearance in 2008, synthetic cannabinoid receptor agonists (SCRAs) remain the most popular new psychoactive substances (NPS) in the EU. Following consumption, these drugs and their metabolites are urinary excreted and enter the sewage system enabling the application of wastewater‐based epidemiology (WBE). Knowing the fate of target analytes in sewage water is essential for successful application of WBE. This study investigates the stability of several chemically diverse SCRAs and selected human metabolites under sewage conditions utilizing a combination of liquid chromatography–tandem mass spectrometry and high‐resolution mass spectrometry (HRMS). Target analytes included SCRAs with indole (5F‐PB‐22, PB‐22 pentanoic acid), indazole (AMB‐FUBINACA, 5F‐ADB, 5F‐ADB dimethylbutanoic acid), carbazole (MDMB‐CHMCZCA, EG‐018), and γ‐carboline (Cumyl‐PeGaClone) chemical core structures representing most of the basic core structures that have occurred up to now. Stability tests were performed using wastewater effluent containing 5% activated sludge as inoculum to monitor degradation processes and formation of transformation products (TPs). The majority of investigated SCRAs, excluding the selected human metabolites, was recalcitrant to microbial degradation in sewage systems over a period of 29 days. Their stability was rather controlled by physico‐chemical processes like sorption and hydrolysis. Considering a typical hydraulic in‐sewer retention time of 24 h, the concentration of AMB‐FUBINACA decreased by 90% thus representing the most unstable SCRA investigated in this study. Among the 10 newly identified TPs, three could be considered as relevant markers and should be included into future WBE studies to gain further insight into use and prevalence of SCRAs on the drug market.

Fragmentation flagging (FF), a high-resolution mass spectrometric screening variant that utilizes intentionally produced indicative in-source fragments, was used to screen for per- and polyfluoroalkyl substances (PFASs) in surface waters. Besides expected legacy PFAS, FF enabled the detection of some rarely investigated representatives, such as trifluoromethanesulfonic acid (TFMSA). Additionally, a novel PFAS was detected and identified as tris(pentafluoroethyl)trifluorophosphate (FAP) via MS/MS experiments and confirmed with a reference standard. The first monitoring of FAP in 20 different surface waters revealed a localized contamination affecting three connected rivers with peak concentrations of up to 3.4 μg/L. To the best of our knowledge, this is the first time FAP has been detected in environmental water samples. The detection of FAP, which is exclusively used as a constituent of ionic liquids (ILs), raises questions about the environmental relevance of ILs in general and particularly fluorinated ILs. A following comprehensive literature search revealed that ILs have already been intensely discussed as potential environmental contaminants, but findings reporting ILs in environmental (water) samples are almost non-existent. Furthermore, we address the relevance of ILs in the context of persistent, mobile, and toxic chemicals, which are at present gaining increasing scientific and regulatory interest, and as part of the PFAS “dark matter” that represents the gap between the amount of fluorine originating from known PFAS and the total adsorbable organically bound fluorine. Graphical abstract

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are applied during the production of various consumer and industrial goods. As a consequence of their use in building materials and fabrics, unreacted nonpolymeric PFASs might enter the environment by evaporation or urban run-off. Since the PFAS content of building materials and industrial fabrics is hardly investigated, studies have to be performed in order to assess their total PFAS load. Building material samples (n = 23) and fabric samples (n = 28) were collected and their PFAS content was investigated. A total of 29 PFASs were analyzed (chain length in the range of C₄–C₁₄). PFASs of diverse chain lengths were detected in 53% of the analyzed samples. The sum of PFASs for awning materials and coating samples were amongst the highest. Furthermore, PFASs were detected in the majority of fabrics for maritime applications, public transport seat covers and fluoropolymer facade materials. To the best of our knowledge, this study was the first to investigate the PFAS concentrations in fabrics for maritime applications, fluoropolymer facade materials and coatings for architectural purposes. Thus, new sources of PFASs were identified that might lead to release of PFASs into the environment.

There is a high demand for easy, cheap, comparable, and robust methods for microplastic (MP) analysis, due to the ever-increasing public and scientific interest in (micro-) plastic pollution in the environment. Today, a multitude of methodologies for sampling, sample preparation, and analysis of MPs are in use. This feature article deals with the most prominent detection methods as well as with sampling strategies and sample preparation techniques. Special emphasis is on their benefits and challenges. Thus, spectroscopic methods, coupled with microscopy, require time-consuming sample preparation and extended measurement times, whereas thermo-analytical methods are faster but lack the ability to determine the size distribution in samples. To that effect, most of the described methods are applicable depending on the defined analytical question.