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Previously unknown phenylarsenic chemicals that originated from chemical warfare agents (CWAs) have been detected and identified in sediment samples collected from the vicinity of chemical munition dumpsites. Nontargeted screening by ultrahigh-performance liquid chromatography–high-resolution mass spectrometry (UHPLC-HRMS) was used for detection of 14 unknown CWA-related phenylarsenic chemicals. Methylated forms of Clark I/II, Adamsite, and phenyldichloroarsine were detected in all analyzed sediment samples, and their identification was based on synthesized chemicals. In addition, other previously unknown CWA-related phenylarsenic chemicals were detected, and their structures were elucidated using MS/HRMS technique. On the basis of relative isotope ratios of protonated molecules and measures of exact masses of formed fragment ions, it could be concluded that some of these unknown chemicals contained a sulfur atom attached to an arsenic atom. In addition to that, some of the samples contained chemicals that had formed via addition of an OH group to the aromatic ring. However, it is not possible to say how these chemicals are formed, but the most plausible cause is activities of marine microbes in the sediment. To our knowledge, these chemicals have not been detected from sediment samples previously. Sensitive analytical methods are needed for these novel chemicals to assess the total CWA burden in marine sediments, and this information is essential for the risk assessment.

About 50 000 tons of chemical weapons (CW) were dumped to the Baltic Sea after the Second World War. Munitions are located in the deep areas of the Baltic Sea, and there they act as a point source of contamination to the ecosystem. Corroded munitions release chemical warfare agents (CWAs) to nearby water and sediments. In this study we investigated known dumpsites (Bornholm, Gotland and Gdansk Deep) and dispersed chemical munitions, to evaluate the extent of contamination of nearby sediments, as well as to assess the degradation process of released CWA. It was found that CWA-related phenylarsenic chemicals (Clark I, Clark II and Adamsite) and sulfur mustard are released to the sediments and undergo environmental degradation to chemicals, of which some remain toxic. The extent of pollution of released CWAs and their corresponding degradation products reaches more than 250 m from the CW objects, and seem to follow a power curve decrease of concentration from the source. Bornholm Deep is characterised with the highest concentration of CWAs in sediments, but occasional concentration peaks are also observed in the Gdansk Deep and close to dispersed munitions. Detailed investigation of spreading pattern show that the range of pollution depends on bottom currents and topography.

A new method has been developed to determine oxidation products of three chemical warfare agent (CWA) related phenylarsenic compounds from marine biota samples by a liquid chromatography-heated electrospray ionization/tandem mass spectrometry (LC-HESI/MS/MS). The target chemicals were oxidation products of Adamsite (DM[ox]), Clark I (DPA[ox]), and triphenylarsine (TPA[ox]). Method was validated within the concentration range of 1-5, 0.2-5, and 0.2-5 ng/g for DM[ox], DPA[ox], and TPA[ox], respectively. The method was linear, precise and accurate. Limits of quantification (LOQ) were 2.0, 1.3, and 2.1 ng/g for DM[ox], DPA[ox], and TPA[ox], respectively. A total of ten fish samples and one lobster sample collected from near Swedish coast, Måseskär dumpsite were analyzed. Trace concentrations below LOQ values were detected in three samples and the elemental composition of oxidized form of Clark I and/or II was confirmed by LC-HESI/HRMS. To our knowledge, this is the first study that provides the presence of CWA related chemicals in marine biota samples.

Chemical Munitions Search & Assessment (CHEMSEA) project has performed studies on chemical weapon (CW) detection, sediment pollution and spreading as well as biological effects of chemical warfare agents (CWAs) dumped in the Baltic Sea. Results suggest that munitions containing CWAs are more scattered on the seafloor than suspected, and previously undocumented dumpsite was discovered in Gdansk Deep. Pollution of sediments with CWA degradation products was local and close to the detected objects; however the pollution range was larger than predicted with theoretical models. Bottom currents observed in the dumpsites were strong enough for sediment re-suspension, and contributed to the transport of polluted sediments. Diversity and density of the faunal communities were poor at the dumping sites in comparison to the reference area, although the direct effects of CWA on benthos organisms were difficult to determine due to hypoxic or even anoxic conditions near the bottom. Equally, the low oxygen might have affected the biological effects assessed in cod and caged blue mussels. Nonetheless, both species showed significantly elevated molecular and cellular level responses at contaminated sites compared to reference sites.

Capsaicin and dihydrocapsaicin are the major active components in pepper spray products, which are widely used for law enforcement and self-protection. The use of pepper sprays, due to their irreversible and other health effects has been under a strong debate. In this study, we compared metabolism and cytotoxicity of capsaicin and dihydrocapsaicin using human and pig liver cell fractions and human lung carcinoma cell line (A549) in vitro. Metabolites were screened and identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Using liver cell fractions, a novel aliphatic hydroxylated metabolite (m/z 322) was detected to dihydrocapsaicin but no structure was found corresponding to capsaicin. Instead, a novel phase I metabolite of capsaicin, corresponding to the structure of aliphatic demethylation and dehydrogenation (m/z 294) was identified. In addition, two novel conjugates, glycine conjugates (m/z 363 and m/z 365) and bi-glutathione (GSH) conjugates (m/z 902 and m/z 904), were identified for both capsaicin and dihydrocapsaicin. The medium of the exposed A549 cells contained ω-hydroxylated (m/z 322) and alkyl dehydrogenated (m/z 304) forms, as well as a glycine conjugate of capsaicin. As to dihydrocapsaicin, an alkyl dehydrogenated (m/z 306) form, a novel alkyl hydroxylated form, and a novel glycine conjugate were found. In A549 cells, dihydrocapsaicin evoked vacuolization and decreased cell viability more efficiently than capsaicin. Furthermore, both compounds induced p53 protein and G1 phase cell cycle arrest. Usefulness of the found metabolites as biomarkers for capsaicinoid exposures will need further investigations with additional toxicity endpoints.

We estimate the “macro effect” of an increase in the generosity of unemployment insurance (UI) on unemployment in Sweden using regional data. The national UI benefit formula features a benefit ceiling and a statutory replacement rate, and does not take regional wage differentials into account. Changes in the national rules are useful for identification, since a change in the benefit ceiling, for example, has a greater impact on UI generosity in a high-wage region than in a low-wage region because a greater fraction of the workforce will be affected by the benefit ceiling in the high-wage region. We implement this identification strategy using data for the Swedish municipalities over the time period 1992–2014. Our estimates suggest that the macro elasticity of an increase in UI on unemployment is around 3. This is twice as large as the corresponding “micro elasticity”, which we estimate to 1.4–1.5 using data from the same time period.

A saxitoxin (STX) proficiency test (PT) was organized as part of the Establishment of Quality Assurance for the Detection of Biological Toxins of Potential Bioterrorism Risk (EQuATox) project. The aim of this PT was to provide an evaluation of existing methods and the European laboratories' capabilities for the analysis of STX and some of its analogues in real samples. Homogenized mussel material and algal cell materials containing paralytic shellfish poisoning (PSP) toxins were produced as reference sample matrices. The reference material was characterized using various analytical methods. Acidified algal extract samples at two concentration levels were prepared from a bulk culture of PSP toxins producing dinoflagellate Alexandrium ostenfeldii. The homogeneity and stability of the prepared PT samples were studied and found to be fit-for-purpose. Thereafter, eight STX PT samples were sent to ten participating laboratories from eight countries. The PT offered the participating laboratories the possibility to assess their performance regarding the qualitative and quantitative detection of PSP toxins. Various techniques such as official Association of Official Analytical Chemists (AOAC) methods, immunoassays, and liquid chromatography-mass spectrometry were used for sample analyses.

This chapter summarizes the methods used within the MODUM project for monitoring chemical munition dumpsites. It includes general introduction to monitoring process, listing the requirements that are a basis for the establishment of full scale monitoring programme. It describes survey procedures, for locating dumped munitions, Sampling and analytical procedures for the detection of Chemical Warfare Agents, as well as the usage of fish as bioindicators are described. Modelling of pollutants originating from dumped munitions is presented and discussed. Only methods, which were proven to be most effective within the MODUM projects were selected, also data interpretation methods providing coherent information regarding the environmental risk are explained in details.

MODUM project continued the work on monitoring of the chemical weapons (CW) dumped in the Baltic Sea started in previous projects. As a new aspect, on board analysis methods – headspace gas chromatography-mass spectrometry (GC–MS) and capillary electrophoresis (CE) – were developed and tested in laboratory conditions and during cruises. The GC–MS method could be successfully applied on board to verify that collected sediment samples contained degradation products for sulfur mustard, one of the major chemical warfare agents dumped in Baltic Sea. This method could in future project be used during cruises to redirect sample collection in order to make most of the available ship time. Other part of the analysis task during MODUM project was the work done at the reach back laboratories. These analyses were done to both verify the results obtain on board and to fully identify the chemicals related to the sea-dumped CW agents. Reach back analysis of CW-related chemicals were done on sediment samples collected around a wreck in Bornholm Deep (same samples as analyzed on board) and on monitoring samples collected in Bornholm, Gotland and Gdansk Deeps. The samples from Bornholm and Gotland Deeps are in line with previous findings. Samples from Gdansk Deep are in line with previous findings that this area has been used as a dump site. Additionally, α-chloroacetophenone (CN) was found in the area for the first time. In addition to the analysis of CW-related chemicals, a new method was developed for measurement for arsenic concentrations in sediment samples. A method was also developed for arsenic speciation, which could help in estimation of the source of arsenic in the sediments.

Uropathogenic Escherichia coli often produce the virulence factor α-hemolysin (HlyA), and the more severe the infection, the likelier it is to isolate HlyA-producing E. coli from patients. HlyA forms pores upon receptor-independent insertion of the toxin into biological membranes and it has been substantiated that HlyA-induced hemolysis is amplified by toxin-induced ATP release and activation of P2X receptors. Thus, hemolysis inflicted by HlyA is a protracted process involving signal transduction. It consists of early, marked cell shrinkage followed by swelling and eventually lysis. The initially shrinkage is a consequence of a substantial Ca(2+)-influx and activation of Ca(2+)-sensitive K(+) and Cl(-) channels (KCa3.1/TMEM16A). The shrinkage is followed by gradual cell swelling, which ultimately lyses the cells. These findings clearly show that the HlyA pore provides a substantial volume challenge for the cells, and the fate of the given cell is co-determined by intrinsic erythrocytal volume regulation. We therefore speculated that other mechanisms involved in erythrocyte volume regulation may influence the hemolytic process inflicted by HlyA. Strikingly, HlyA-induced hemolysis is markedly reduced in erythrocytes isolated from NKCC1-deficient (NKCC1(-/-)) mice compared to controls. The NKCC1 inhibitors furosemide and bumetanide concentration-dependently inhibit HlyA-induced lysis of human and murine erythrocytes. However, in high concentrations bumetanide further reduced hemolysis in erythrocytes from NKCC1(-/-) mice and, thus, also exhibit indirect effects on hemolysis. The effect of loop diuretics on the hemolysis is not unique to HlyA but is similarly seen in LtxA- and α-toxin-induced hemolysis. Bumetanide clearly potentiates HlyA-induced volume reduction and delays the following erythrocyte swelling. This allows increased phagocytosis of damaged erythrocytes by THP-1 cell as a result of prolonged cell shrinkage. These data suggest that erythrocyte susceptibility to cytolysins is modified by NKCC1 and signifies intrinsic volume regulators as important determinants of cellular outcome of pore-forming toxins.

The identification of chemicals that pose the greatest threat to human health from incidental releases is a cornerstone in public health preparedness for chemical threats. The present study developed and applied a methodology for the risk analysis and prioritization of industrial chemicals to identify the most significant chemicals that pose a threat to public health in Finland. The prioritization criteria included acute and chronic health hazards, physicochemical and environmental hazards, national production and use quantities, the physicochemical properties of the substances, and the history of substance-related incidents. The presented methodology enabled a systematic review and prioritization of industrial chemicals for the purpose of national public health preparedness for chemical incidents.

Summary Leukotoxin (LtxA) is a virulence factor secreted by the bacterium Aggregatibacter actinomycetemcomitans, which can cause localized aggressive periodontitis and endocarditis. LtxA belongs to the repeat-in-toxin (RTX) family of exotoxins of which other members inflict lysis by formation of membrane pores. Recently, we documented that the haemolytic process induced by another RTX toxin [α-haemolysin (HlyA) from Escherichia coli] requires P2X receptor activation and consists of sequential cell shrinkage and swelling. In contrast, the cellular and molecular mechanisms of LtxA-mediated haemolysis are not fully understood. Here, we investigate the effect of LtxA on erythrocyte volume and whether P2 receptors also play a part in LtxA-mediated haemolysis. We observed that LtxA initially decreases the cell size, followed by a gradual rise in volume until the cell finally lyses. Moreover, LtxA triggers phosphatidylserine (PS) exposure in the erythrocyte membrane and both the shrinkage and the PS-exposure is preceded by increments in the intracellular Ca2+ concentration ([Ca2+]i). Interestingly, LtxA-mediated haemolysis is significantly potentiated by ATP release and P2X receptor activation in human erythrocytes. Furthermore, the LtxA-induced [Ca2+]i increase and following volume changes partially depend on P2 receptor activation. Theseobservations imply that intervention against local P2-mediated auto- and paracrine signalling may prevent LtxA-mediated cell damage.

This paper studies the effects of school choice on segregation. We analyze the effect of a reform in Stockholm that changed the admission system of public upper secondary schools. Before the year 2000, students had priority to the school situated closest to where they lived, but from the fall of 2000 and onwards, admission is based on grades only. We show that the distribution of students over schools changed dramatically as a response to extending school choice. As expected, the new admission policy increased segregation by ability. However, segregation by family background, as well as, segregation between immigrants and natives also increased significantly. Keywords: School choice, Segregation. JEL classification: I21, I28, J24 This paper studies the effects of school choice on segregation. We analyze the effect of a reform in Stockholm that changed the admission system of public upper secondary schools. Before the year 2000, students had priority to the school situated closest to where they lived, but from the fall of 2000 and onwards, admission is based on grades only. We show that the distribution of students over schools changed dramatically as a response to extending school choice. As expected, the new admission policy increased segregation by ability. However, segregation by family background, as well as, segregation between immigrants and natives also increased significantly. Keywords: School choice, Segregation. JEL classification: I21, I28, J24

The wage-setting for Swedish teachers was up and until 1996 characterized by centralized bargaining and wage scales. According to the scales, wages were exclusively determined by teacher type and years in the profession. In 1996, the scale system was replaced by individual wage bargaining. This study uses this change in bargaining structure to examine whether the scale system was a binding constraint on the wage-setting. The results suggest that the scales did impose such a constraint, since the earnings structure changed after the reform. More precisely, entry-wages and earnings dispersion increased.

Near- and supercritical D2O is both a relatively cheap deuterium source and an environmentally benign solvent for batch-wise H/D exchange reactions. In this work, a new continuous flow reactor online-coupled with liquid–liquid extraction was constructed for the selective deuteration of aromatic hydrocarbons in pressurized hot D2O at short contact times. Exchange positions were identified by GC–MS, 1H NMR, and FTIR analysis. Four aromatic hydrocarbons (eugenol, 9-fluorenone, 4-hydroxyacetophenone, and xanthone) were screened for H/D exchange in conventional batch reactors with use of near- and supercritical D2O (p = 300 bar, t = 2 h, T = 250–450 °C) alone and with basic or metal catalyst (Na2CO3, Pd/C). Highest isotopic purities were obtained for deuteration of eugenol (d1 = 59%) and 4-hydroxyacetophenone (d5 = 91%) in the absence of catalyst. 2H-labelling of these two compounds was then investigated in continuous flow experiments (p = 300 bar, T = 250–350 °C, τ = 1–4 min). Under optimized conditions, high isotopic purities were obtained for eugenol (d1 = 61%) and 4-hydroxyacetophenone (d5 = 82%), as before in batch runs, but the contact time, and the probability of decomposition, were significantly reduced. The continuous process developed offers good potential for the deuteration of thermally sensitive substrates.

Ricinus communis intoxications have been known for centuries and were attributed to the toxic protein ricin. Due to its toxicity, availability, ease of preparation, and the lack of medical countermeasures, ricin attracted interest as a potential biological warfare agent. While different technologies for ricin analysis have been established, hardly any universally agreed-upon “gold standards” are available. Expert laboratories currently use differently purified in-house materials, making any comparison of accuracy and sensitivity of different methods nearly impossible. Technically challenging is the discrimination of ricin from R. communis agglutinin (RCA120), a less toxic but highly homologous protein also contained in R. communis. Here, we established both highly pure ricin and RCA120 reference materials which were extensively characterized by gel electrophoresis, liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI MS/MS), and matrix-assisted laser desorption ionization–time of flight approaches as well as immunological and functional techniques. Purity reached &gt, 97% for ricin and &gt, 99% for RCA120. Different isoforms of ricin and RCA120 were identified unambiguously and distinguished by LC-ESI MS/MS. In terms of function, a real-time cytotoxicity assay showed that ricin is approximately 300-fold more toxic than RCA120. The highly pure ricin and RCA120 reference materials were used to conduct an international proficiency test.

A method for detecting mustard gas degradation products thiodiglycol (TDG) and thiodiglycol sulfoxide (TDGO) in water and sediment samples using gas chromatography-tandem mass spectrometry (GC-MS/MS) after derivatization with 1-(trifluoroacetyl)imidazole (TFAI) was described. Selected reaction monitoring mode (SRM) of tandem mass spectrometry was developed for analysis of TDG and TDGO derivatives while analysis by gas chromatography-atomic emission detector (GC-AED) was performed using the 181 nm sulfur canal. TFAI derivatization conditions were optimized and the method validated. Two derivatization agents were compared, TFAI and N,O-bis(trimethylsilyl) trifluoroacetamide (BSTFA), where derivatization using TFAI occurred quicker and under milder conditions than using BSTFA. Water samples containing TDG and TDGO were evaporated to dryness under nitrogen, dissolved in organic solvent followed by reaction with TFAI. The limit of detection (LOD) for TDG and TDGO were 0.01 and 5 ng/mL, respectively. The limit of detection for TDG was decreased by two orders of magnitude if TFAI is used for derivatization rather than silyl derivatizing agents (e.g., BSTFA). TFAI has three major advantages in comparison to BSTFA, the first is much higher sensitvity, the second is a very clean background of chromatograms, and the last one is very mild conditions of derivatization. Moreover, by-products are not formed during derivatization of TDGO by TFAI in comparison to derivatization by silylating agents.

The results of an international trial proficiency testr are described. Compounds relevant to the Chemical Weapons Convention were analyzed in rubber, paint and two soil samples by using GC with selective detectors, GC-MS and GC-FTIR. The analytical strategy is presented both for routine analyses and for spectral interpretation of a compound for which no reference spectra are available. Three examples are given of spectral interpretation of alkylphosphonates.

GC-FTIR spectra of 55 nerve agent homologues and dialkyl methylphosphonates have been analyzed. Infrared spectral library searches together with retention index searches have been used for identification of nerve agent homologues and dialkyl methylphosphonates.

Leukotoxin (LtxA) is a virulence factor secreted by the bacterium Aggregatibacter actinomycetemcomitans, which can cause localized aggressive periodontitis and endocarditis. LtxA belongs to the repeat-in-toxin (RTX) family of exotoxins of which other members inflict lysis by formation of membrane pores. Recently, we documented that the haemolytic process induced by another RTX toxin [α-haemolysin (HlyA) from Escherichia coli] requires P2X receptor activation and consists of sequential cell shrinkage and swelling. In contrast, the cellular and molecular mechanisms of LtxA-mediated haemolysis are not fully understood. Here, we investigate the effect of LtxA on erythrocyte volume and whether P2 receptors also play a part in LtxA-mediated haemolysis. We observed that LtxA initially decreases the cell size, followed by a gradual rise in volume until the cell finally lyses. Moreover, LtxA triggers phosphatidylserine (PS) exposure in the erythrocyte membrane and both the shrinkage and the PS-exposure is preceded by increments in the intracellular Ca(2+) concentration ([Ca(2+)](i)). Interestingly, LtxA-mediated haemolysis is significantly potentiated by ATP release and P2X receptor activation in human erythrocytes. Furthermore, the LtxA-induced [Ca(2+)](i) increase and following volume changes partially depend on P2 receptor activation. Theseobservations imply that intervention against local P2-mediated auto- and paracrine signalling may prevent LtxA-mediated cell damage.

GC-Direct deposition-FTIR spectra of 55 nerve agent homologues and dialkyl methylphosphonates were analysed. Spectral features of these compounds are discussed. A method is proposed for identification of the alkyl and alkoxy groups of compounds belonging to sarin, tabun or dialkyl methylphosphonates families.

We study income responses to income tax changes by using a large panel of Swedish tax payers over the period 1991–2002. Changes in statutory tax rates as well as changes in tax bracket thresholds provide exogenous variations in tax rates that can be used to identify income responses. We estimate dynamic income models which allow us to distinguish between short-run and long-run effects in a straightforward fashion. For men, the estimates of the long-run elasticity of income with respect to the net-of-tax rate hover in a range between 0.10 and 0.30. The estimates for women are statistically insignificant. We simulate the fiscal consequences of a tax reform that reduces the top marginal tax rate by five percentage points. Such a reform may have negligible effects on tax revenues when the interactions between income taxes and other taxes are taken into account.

This paper discusses the results of geophysical and chemical investigations carried out in a chemical munition dumpsite in the southern Baltic Sea, east of the island of Bornholm. After WW2 over 32,000 tons of chemical war material was dumped here including shells and bombs as well as small drums and containers. The geophysical investigations combined very-high-resolution seismics and gradiometric measurements. The results indicate the presence of a large number of objects buried just below the seafloor. The size of the objects and their distribution, with a marked increase in density towards the center of the dumpsite, suggests that we are dealing with dumped war material. Sediment and near-bottom water samples, taken within the dumpsite and in the surrounding area, were analysed for the presence of various chemical warfare agents (CWA) including Adamsite, Clark, sulphur mustard, tabun, chlorobenzene and arsine oil. The results indicate a widespread contamination that reaches far beyond the dumpsite boundary. CWA degradation products were found in most of the sediment samples. The contamination was mostly related to arsenic containing compounds; only one sample indicated the presence of sulfur mustard. Although the correlation between detected objects and CWA concentrations is not always straightforward, the overall results suggest that a lot of the dumped war material is leaking and that over the years the contamination has reached the seafloor sediments.

Fourier transform infrared spectroscopy (FTIR) is an analytical technique, which gives characteristic spectra. The spectra can be used like fingerprints in the identification of chemicals. The chemicals can be identified by comparison with reference data or, in some cases, by interpretation, which can be followed by synthesis for confirmation. When FTIR is connected to a gas chromatograph (GC) and the results are used together with those from mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy, very complex environmental samples containing unknown chemicals can be analyzed reliably.