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Major public health concern is raised by the evidence that common drugs like heroin are now frequently laced or replaced with highly potent novel synthetic opioids (NSOs). The objective of this study was to explore the prevalence and patterns of NSOs in a cohort of Swiss opioid users by hair analysis. Hair analysis is considered an ideal tool for retrospective consumption monitoring. Hair samples from 439 opioid users in Zurich were analyzed. Study inclusion required a previous positive hair test result for heroin metabolites, oxycodone, fentanyl, methadone, or tramadol. The samples were extracted with a two‐step extraction procedure, followed by a targeted LC–MS/MS (QTRAP® 6500+) analysis in multiple reaction monitoring mode for a total of 25 NSOs. The method underwent full validation and demonstrated good selectivity and sensitivity with limits of detection (LOD) as low as 0.1 pg/mg. The analyzed sample cohort demonstrated a positivity rate for NSOs of 2.5%, including the following NSOs: butyrylfentanyl, acrylfentanyl, furanylfentanyl, methoxyacetylfentanyl, ocfentanil, U‐47700, isobutyrylfentanyl and benzylfentanyl. Furthermore, we were able to identify specific consumption patterns among drug users. The results indicate that hair analysis is a valuable tool for investigating the prevalence of NSOs in drug‐using populations, which seems to be low in the case of Swiss opioid users. Nevertheless, the results highlight the need for sensitive analytical detection methods in forensic toxicology to identify and monitor substance distribution in different populations.

Chlorinated paraffins (CPs) are high production volume chemicals. Their analysis is demanding and becomes even more challenging in presence of CP transformation products. Chlorinated olefins (COs) are expected thermal CP transformation products that are present in technical CP products and in the environment. Thus, a specific analysis of CPs and COs is important. Commonly, CPs are analysed by gas chromatography electron capture negative ionisation mass spectrometry (GC-ECNI-MS). It was shown that GC-ECNI-MS suffers from in-source formation of COs. Further, selected ion monitoring can lead to false quantification of COs as CPs. Alternative methods based on liquid chromatography and soft ionisation techniques can solve the CP/CO problem. Non-interfered CP data is inevitable for CP transformation studies and non-biased degradation kinetics. Data about CP transformation is urgently needed, but respective studies are challenging. In here, we provided an analytical guide to deal with severe mass interferences of CPs and their transformation products.

Chlorinated paraffins (CPs) are high production volume chemicals and ubiquitous environmental pollutants. In particular, data about the environmental fate of medium-chain (MCCPs, C14–C17) and long-chain (LCCPs, C≥18) CPs are urgently needed. Their analysis requires elaborate analytical methods and representative analytical standards. Complex mixtures that contain CPs of different carbon chain lengths and degrees of chlorination are currently used for quantification but are impractical when chain length distributions substantially differ between samples and standards. Single-chain CP mixtures of only one carbon chain length but varying degrees of chlorination are more suitable for accurate quantification but are not available for MCCPs and LCCPs. Such standards are useful for homologue pattern deconvolution and response factor calculations. Toxicity and transformation studies on MCCPs and LCCPs are scarce. Respective studies would also benefit from less complex CP standards, e.g., single-chain mixtures or even constitutionally defined CPs. Currently available analytical standards are inadequate for the demanding task of quantifying MCCPs and LCCPs. Improved standards are required. This review provides an overview of the available analytical CP materials, discusses their advantages and disadvantages for accurate CP analysis, and gives a recommendation for improvements. Recommendations for improved analytical standards include (A) complex CP mixtures that better resemble technical CP mixtures, (B) single-chain CP mixtures of different carbon chain lengths (C10–C30) and varying degrees of chlorination (40–70 wt%Cl), (C) constitutionally defined CPs with representative chlorination patterns, and (D) isotopically labeled CP isomers that represent a broad range of CPs.

Accurate quantification of short-chain chlorinated paraffins (SCCPs) poses an exceptional challenge to analytical chemists. SCCPs are complex mixtures of chlorinated alkanes with variable chain length and chlorination level; congeners with a fixed chain length (n) and number of chlorines (m) are referred to as a congener group CnClm Recently, we resolved individual CnClm by mathematically deconvolving soft ionization high-resolution mass spectra of SCCP mixtures. Here we extend the method to quantifying CnClm by introducing CnClm specific response factors (RFs) that are calculated from 17 SCCP chain-length standards with a single carbon chain length and variable chlorination level. The signal pattern of each standard is measured on APCI-QTOF-MS. RFs of each CnClm are obtained by pairwise optimization of the normal distribution's fit to the signal patterns of the 17 chain-length standards. The method was verified by quantifying SCCP technical mixtures and spiked environmental samples with accuracies of 82-123% and 76-109%, respectively. The absolute differences between calculated and manufacturer-reported chlorination degrees were 0.9 to 1.0%Cl for SCCP mixtures of 49-71%Cl. The quantification method has been replicated with ECNI magnetic sector MS and ECNI-Q:Orbitrap-MS. CnClm concentrations determined with the three instruments were highly correlated (R-2 > 0.90) with each other.

We describe and illustrate a three-step data-processing approach that enables individual congener groups of chlorinated-paraffins (CPs) to be resolved in mass spectra obtained from either-of two soft ionization methods: electron capture negative-ionization mass spectrometry (ECNI-MS) or atmospheric pressure chemical ionization mass spectrometry (APCI-MS). In the first step, general fragmentation pathways of CPs are deduced from analysis of mass spectra of individual CP congeners. In the-Second step, all possible fragment ions in the general fragmentation pathways of CPs with 10 to 20 carbon atoms are enumerated and compared to mass spectra of CP mixture standards, and a deconvolution algorithm is applied to identify fragment ions that are actually observed. In the third step, isotope permutations of the observed fragment ions are calculated and used to identify isobaric overlaps, so that mass intensities of indivichial CP congener groups can be deconvolved from the unresolved isobaric ion signal intensities in mass spectra. For a specific instrument; the three steps only need to be done once to enable deconvolution of CPs in unknown samples. This approach enables congener group-level resolution of CP mixtures in environmental samples, and: it opens up the possibility, for quantification of congener group.

More than a decade ago, the Stockholm Convention on Persistent Organic Pollutants (POPs), one of the multilateral environmental agreements administered by the United Nations Environment Programme (UNEP), entered into force. The objective of this Convention is to protect human health and the environment by controlling the releases of POPs. According to its Article 16, the effectiveness of the Stockholm Convention shall be evaluated using comparable monitoring data on the presence of POPs as well as their regional and global environmental transport. Here, we present a time series analysis on atmospheric POP concentrations from 15 monitoring stations in North America and Europe that provide long-term data and have started operations between 1990 and 2003. We systematically searched for temporal trends and significant structural changes in temporal trends that might result from the provisions of the Stockholm Convention. We find that such structural changes do occur, but they are related mostly to effects of national regulations enforced prior to the implementation of the Stockholm Convention, rather than to the enforcement of the provisions laid out in the Convention. One example is that concentrations of polychlorinated biphenyls, many of which started to decrease rapidly during the 1990s. Also effects of chemical transport and fate, for instance the re-volatilization of POPs from secondary sources, are thought to be a cause of some of the observed structural changes. We conclude that a decade of air monitoring data has not been sufficient for detecting general and statistically significant effects of the Stockholm Convention. Based on these lessons, we present recommendations for the future operation of existing monitoring programs and advocate for a stricter enforcement of the provisions of the Stockholm Convention, in the current absence of proof for its effectiveness., Funding Agencies:U.S. Environmental Protection Agency's Great Lakes National Program Office GL 00E01422Environment and Climate Change Canada's Chemicals Management Plan (CMP)UNEP Chemicals BranchGovernment of Norway 52-P5Global Environment Facility (GEF) 4B97AMAPEMEPNorwegian Environmental Directorate 15078042

Chlorinated paraffins (CPs) are high production volume chemicals, but data about their environmental fate are scarce. CP mixtures composed of thousands of isomers represent a major challenge for quantification at low levels in environmental samples. Here, we present a novel analytical method for analysis of short-chain, medium-chain, and long-chain CPs in a single injection, that also yields information about congener group pattern. Our detection method is based on direct injection into an atmospheric pressure chemical ionization source operated in negative ion mode under chlorine-enhanced conditions, followed by quadrupole time-of-flight high-resolution mass spectrometry (APCI-qTOF-HRMS) operated in full-scan mode. A mathematical algorithm is applied to deconvolute the CP patterns in the analyzed samples into a linear combination of patterns of technical CP mixtures and to quantify CPs using technical mixtures as external calibration standards. For CP mixtures with known composition, the new method provided concentrations that were within a factor of 1.2 of the target value. Accuracies for CPs spiked to sediment and fish extracts were between 91% and 123%. Concentrations determined in unspiked field samples were within a factor of 5 for short-chain CPs and a factor of 16 for medium-chain CPs of results obtained with an independent method based on gas chromatography/electron capture negative ionization high-resolution mass spectrometry (GC/ECNI-HRMS). The presented APCI-qTOF-HRMS pattern deconvolution method is an interesting alternative for CP analysis in environmental samples. It is particularly sensitive for medium- and long-chain CPs and has the advantage of being extremely fast (instrumental analysis time, less than 1 min)., AuthorCount:5

Between 60% and 80% of all marine litter is plastic. Leachate from plastics has previously been shown to cause acute toxicity in the freshwater species Daphnia magna. Here, we present an initial screening of the marine environmental hazard properties of leachates from weathering plastics to the marine harpacticoid copepod [Crustacea] Nitocra spinipes. Twenty-one plastic products made of different polymeric materials were leached and irradiated with artificial sunlight. Eight of the twenty-one plastics (38%) produced leachates that caused acute toxicity. Differences in toxicity were seen for different plastic products, and depending on the duration of irradiation. There was no consistent trend in how toxicity of leachate from plastics changed as a function of irradiation time. Leachate from four plastics became significantly more toxic after irradiation, two became significantly less toxic and two did not change significantly. Analysis of leachates from polyvinyl chloride (PVC) by liquid chromatography coupled to a full-scan high-resolution mass spectrometer showed that the leachates were a mixture of substances, but did not show evidence of degradation of the polymer backbone. This screening study demonstrates that leachates from different plastics differ in toxicity to N. spinipes and that the toxicity varies under simulated weathering.