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Chemical weapons are a diverse range of substances that can be used to cause intentional death or harm through their toxic properties. They include nerve agents, vesicants, lung-damaging agents, cyanide, biological toxins, and riot control agents, as well as emerging threats such as the highly potent opioid carfentanil. Although infrequent, chemical weapons casualties can and have presented to civilian hospitals as the result of terrorist attacks, assassination attempts, and accidental exposure. Recognition of the potential chemical casualty is required to initiate specific treatment and appropriate personal protective measures. However, this is made challenging by a low index of suspicion, unclear history of exposure, limitations of field-testing equipment, and variable presentations that may be confounded by psychological symptoms, physical injuries, hyperthermia from personal protective equipment (PPE), and the side effects of antidotes. This article gives a brief overview of how to identify and manage chemical incidents, the toxicology, symptomatology, and treatment of a selected number of chemical agents. Further detail can be found in the listed references. [ABSTRACT FROM AUTHOR]

In recent years, various poisoning incidents have been reported, involving the alleged use of the so-called Novichok agents, resulting in their addition to the Schedule I list of the Organisation for the Prohibition of Chemical Warfare (OPCW). As the physicochemical properties of these agents are different from the 'classical' nerve agents, such as VX, research is needed to evaluate whether and to what extent existing countermeasures are effective. Here, we evaluated the therapeutic potential of RSDL® (Reactive Skin Decontamination Lotion Kit) for the neutralization of percutaneous toxicity caused by Novichok agents, both in vitro and in vivo. Experiments showed the three selected Novichok agents (A230, A232, A234) could be degraded by RSDL lotion, but at a different rate. The half-life of A234, in the presence of an excess of RSDL lotion, was 36 min, as compared to A230 (<5 min) and A232 (18 min). Following dermal exposure of guinea pigs to A234, application of the RSDL kit was highly effective in preventing intoxication, even when applied up until 30 min following exposure. Delayed use of the RSDL kit until the appearance of clinical signs of intoxication (3–4 h) was not able to prevent intoxication progression and deaths. This study determines RSDL decontamination as an effective treatment strategy for dermal exposure to the Novichok agent A234 and underscores the importance of early, forward use of skin decontamination, as rapidly as possible. • Novichok agents (A230, A232, A234) could be degraded by RSDL lotion, but at a different rate. • RSDL kit was highly effective in preventing intoxication, even when applied up until 30 min following exposure. • Delayed use of the RSDL kit until the appearance of clinical signs of intoxication (3–4 h) was not effective. • Repeat decontamination by RSDL may prevents acetylcholine esterase inhibition. [ABSTRACT FROM AUTHOR]

Since its first employment in World War I, chlorine gas has often been used as chemical warfare agent. Unfortunately, after suspected release, it is difficult to prove the use of chlorine as a chemical weapon and unambiguous verification is still challenging. Furthermore, similar evidence can be found for exposure to chlorine gas and other, less harmful chlorinating agents. Therefore, the current study aims to use untargeted high resolution mass spectrometric analysis of chlorinated biomarkers together with machine learning techniques to be able to differentiate between exposure of plants to various chlorinating agents. Green spire (Euonymus japonicus), stinging nettle (Urtica dioica), and feathergrass (Stipa tenuifolia) were exposed to 1000 and 7500 ppm chlorine gas and household bleach, pool bleach, and concentrated sodium hypochlorite. After sample preparation and digestion, the samples were analyzed by liquid chromatography high resolution tandem mass spectrometry (LC-HRMS/MS) and liquid chromatography tandem mass spectrometry (LC-MS/MS). More than 150 chlorinated compounds including plant fatty acids, proteins, and DNA adducts were tentatively identified. Principal component analysis (PCA) and linear discriminant analysis (LDA) showed clear discrimination between chlorine gas and bleach exposure and grouping of the samples according to chlorine concentration and type of bleach. The identity of a set of novel biomarkers was confirmed using commercially available or synthetic reference standards. Chlorodopamine, dichlorodopamine, and trichlorodopamine were identified as specific markers for chlorine gas exposure. Fenclonine (Cl-Phe), 3-chlorotyrosine (Cl-Tyr), 3,5-dichlorotyrosine (di-Cl-Tyr), and 5-chlorocytosine (Cl-Cyt) were more abundantly present in plants after chlorine contact. In contrast, the DNA adduct 2-amino-6-chloropurine (Cl-Ade) was identified in both types of samples at a similar level. None of these chlorinated biomarkers were observed in untreated samples. The DNA adducts Cl-Cyt and Cl-Ade could clearly be identified even three months after the actual exposure. This study demonstrates the feasibility of forensic biomarker profiling in plants to distinguish between exposure to chlorine gas and bleach. [Display omitted] • Novel chlorinated biomarkers in vegetation were analyzed by LC-HRMS/MS. • LDA facilitated classification of plants exposed to either chlorine gas or bleach. • Chlorinated DNA and protein adducts were identified using reference standards. • DNA adducts in plants could be detected more than three months after exposure. [ABSTRACT FROM AUTHOR]

• Contributes to conceptual understandings of the sociotechnical landscape. • Empirical study of the understudied role of war in sociotechnical transitions. • Novel insights of multi systemic change between food and military systems. • Outlines the implications of these insights for sustainability transitions research. This paper addresses a major gap in sustainability transitions research: the role of shocks in shaping transition dynamics. The papers focuses on shocks with traumatic consequences, in particular World War I and II. The paper revisits discussions on the sociotechnical landscape in the Multi-Level Perspective (MLP) and Deep Transition framework, offering refined versions of the concepts of systemic and landscape imprinting. It proceeds with a case-study analysis focusing on niche developments during WWI in relation to chemicals and the emergence of chemical warfare, and the lasting impact this shock had on interwar developments, WWII and the post-WWII context. The collective memories of the use of chemical weapons during war and expectations around future use of chemical weapons formed a new backdrop that influenced developments in the food system. Here, food became more tightly intertwined with military imperatives related to preparations regarding the use of chemical and biological weapons. This paper contributes to emerging understandings of how landscape shocks influence sociotechnical change, in particular how these shocks can lead to long lasting tight couplings between socio-technical systems. Two broader research recommendations follow from it. First, more work is needed on the neglected role of war and the military in sociotechnical transitions. Second, in terms of contemporary sustainability challenges, research could consider how landscape events - including the coronavirus pandemic, events related to dramatic biodiversity losses and the climate crisis as well as the traumatic experience of poverty traps and steep rising inequality - may produce trauma and new forms of shared meaning and expectations that impinge on sociotechnical change. [ABSTRACT FROM AUTHOR]

[Display omitted] • The new descriptive models are developed to describe various roll-up and stepwise 1.1.1.2-Tetrafluoroethane breakthrough curves. • A new method is built up to predict 1.1.1.2-Tetrafluoroethane breakthrough curves under higher moisture content. Gas mask and filter adsorber designs are mainly determined by the accurate breakthrough time calculated by fitting descriptive models to breakthrough curves in military chemistry. Currently, in most practical environments, the highly toxic fluoride gas/vapor breakthrough curves with roll-up and/or stepwise breakthrough structures in the C / C 0 < 1.0 range usually occur, which is induced by the existence of pre-adsorbed water vapor. Common and easily modified descriptive breakthrough models have a significant shortcoming in that they are not able to simultaneously fit the above complex breakthrough curves and explain gas desorption, enhanced adsorption again, and stepwise adsorption in the competitive adsorption process. This study adapts three modified descriptive models by introducing a dimensionless breakthrough coefficient to fit roll-up and stepwise 1.1.1.2-Tetrafluoroethane (R134a) breakthrough curves under humid conditions. Results reveal that correlation coefficients between the model and R134a breakthrough data are higher than 0.98, demonstrating that the novel adaptation successfully accounted for R134a desorption, enhanced R134a adsorption again, and R134a stepwise adsorption without significantly increasing the complexity of implementing the models. Further, through relationship curves between fitting parameters and moisture contents, R134a breakthrough curves on activated carbons under a wider moisture content range were successfully predicted. It will greatly reduce the cost of toxic experimentation and improve experimental safety factors. [ABSTRACT FROM AUTHOR]

[Display omitted] • ESIPT based fluorescent chemodosimeter for swift detection of triphosgene. • Highly selective fluorescence quenching response with triphosgene in solution and vapour phase. • The response was quick and sensitive with a response time of 20 s and LOD of 1.3 ppb. • Eco-friendly test strips yield reliable detection of phosgene vapour with distinct fluorescence change. • Real-time application demonstrated by monitoring spillage in soil sample by a reliable test strip. We have developed a glowing fluorescent chemodosimeter that utilizes excited-state intramolecular proton transfer (ESIPT) through a one-step synthesis process. This innovative chemodosimeter exhibited remarkable selectivity and sensitivity in detecting triphosgene, achieving a limit of detection (LOD) of 41 nM. The strong fluorescence of this probe at 504 nm was significantly quenched by triphosgene. This phenomenon is attributed to the formation of a new adduct upon the addition of guest, which restricts the ESIPT process and ultimately completely extinguishes the fluorescence. Furthermore, we have successfully extended the utility of this probe to determine trace amounts of triphosgene in soil samples of varying composition in solution and strip-based experiments. Notably, our chemodosimeter demonstrates effectiveness across a spectrum of soil types, detecting micromolar levels of triphosgene in complex soil matrices with a LOD of 1.59 µM. the promising sensing of triphosgene in complex soil system hold potential detection of extremely toxic chemical warfare presence in the environment. [ABSTRACT FROM AUTHOR]

[Display omitted] Lewisite is a chemical warfare agent intended for use in World War and a potential threat to the civilian population due to presence in stockpiles or accidental exposure. Lewisite-mediated skin injury is characterized by acute erythema, pain, and blister formation. N-acetyl cysteine (NAC) is an FDA-approved drug for acetaminophen toxicity, identified as a potential antidote against lewisite. In the present study, we have explored the feasibility of rapid NAC delivery through transdermal route for potentially treating chemical warfare toxicity. NAC is a small, hydrophilic molecule with limited passive delivery through the skin. Using skin microporation with dissolving microneedles significantly enhanced the delivery of NAC into and across dermatomed human skin in our studies. Microporation followed by application of solution (poke-and-solution) resulted in the highest in vitro delivery (509.84 ± 155.04 µg/sq·cm) as compared to poke-and-gel approach (474.91 ± 70.09 µg/sq·cm) and drug-loaded microneedles (226.89 ± 33.41 µg/sq·cm). The lag time for NAC delivery through poke-and-solution approach (0.23 ± 0.04 h) was close to gel application (0.25 ± 0.02 h), with the highest for drug-loaded microneedles (1.27 ± 1.16 h). Thus, we successfully demonstrated the feasibility of rapid NAC delivery using various skin microporation approaches for potential treatment against lewisite-mediated skin toxicity. [ABSTRACT FROM AUTHOR]

Fungus-growing attine ants are under constant threat from fungal pathogens such as the specialized mycoparasite Escovopsis , which uses combined physical and chemical attack strategies to prey on the fungal gardens of the ants. In defence, some species assemble protective microbiomes on their exoskeletons that contain antimicrobial-producing Actinobacteria. Underlying this network of mutualistic and antagonistic interactions are an array of chemical signals. Escovopsis weberi produces the shearinine terpene-indole alkaloids, which affect ant behaviour, diketopiperazines to combat defensive bacteria, and other small molecules that inhibit the fungal cultivar. Pseudonocardia and Streptomyces mutualist bacteria produce depsipeptide and polyene macrolide antifungals active against Escovopsis spp. The ant nest metabolome is further complicated by competition between defensive bacteria, which produce antibacterials active against even closely related species. • Specialist fungal pathogens attack the nests of fungus-growing ants. • Ants form mutualistic relationships with defensive actinomycete bacteria. • Specialised metabolites underpin these mutualistic and antagonistic interactions. [ABSTRACT FROM AUTHOR]

In the long and intensive search for effective treatments to counteract the toxicity of the chemical warfare (CW) agent sulphur mustard (H; bis(2-chloroethyl) sulphide), the most auspicious and consistent results have been obtained with the drug N -acetylcysteine (NAC), particularly with respect to its therapeutic use against the effects of inhaled H. It is a synthetic cysteine derivative that has been used in a wide variety of clinical applications for decades and a wealth of information exists on its safety and protective properties against a broad range of toxicants and disease states. Its primary mechanism of action is as a pro-drug for the synthesis of the antioxidant glutathione (GSH), particularly in those circumstances where oxidative stress has exhausted intracellular GSH stores. It impacts a number of pathways either directly or through its GSH-related antioxidant and anti-inflammatory properties, which make it a prime candidate as a potential treatment for the wide range of deleterious cellular effects that H is acknowledged to cause in exposed individuals. This report reviews the available literature on the protection afforded by NAC against the toxicity of H in a variety of model systems, including its efficacy in treating the long-term chronic lung effects of H that have been demonstrated in Iranian veterans exposed during the Iran-Iraq War (1980–1988). Although there is overwhelming evidence supporting this drug as a potential medical countermeasure against this CW agent, there is a requirement for carefully controlled clinical trials to determine the safety, efficacy and optimal NAC dosage regimens for the treatment of inhaled H. Image 1 • N -Acetylcysteine (NAC) reduces the toxicity of sulphur mustard (H) in multiple cell types. • NAC reduces the toxic effects of H lung exposure in animal models. • Delayed (~18 yrs) NAC treatment improves lung function in individuals exposed to H. • NAC is considered to be a safe and well tolerated medication in humans. [ABSTRACT FROM AUTHOR]

Choking agent exposure, among them chlorine gas, occurs in household or industrial accidents, chemical warfare and terrorist attacks. Review of published animal and human data regarding the history, pathophysiology, clinical effects and management of chlorine exposure. Highly soluble agents cause quick upper respiratory tract symptoms. Chlorine gas has a medium solubility, also causing delayed lower airway symptoms, mainly due to its oxidizing potential by releasing hypochlorous and hydrochloric acid, but also by interacting with Transient Receptor Potential channels. Eyes may show conjunctival injection, abrasions and corrosions. Burns of the oronasal mucosa and trachea can occur. Dyspnea, bronchospasm and possible retrosternal pain occur frequently. Glottis edema or laryngospasm are acute life-threatening emergencies. Chlorine gas can cause toxic pneumonitis, lung edema and acute respiratory distress syndrome (ARDS). General management includes physical examination, pulse oximetry and arterial blood gases. Eyes should be irrigated, humidified oxygen and inhalative bronchodilators administered. An EKG, cardiac enzymes and complete-blood-count should be obtained if there is retrosternal pain. Routine chest x-ray is not recommended – except if pulmonary edema is suspected. Laryngoscopy should be performed if glottis edema is suspected. Sodium bicarbonate inhalation after chlorine gas inhalation is discussed controversially. Mechanical ventilation with continuous-positive-airway-pressure or intubation/tracheotomy with high positive-end-expiratory-pressure may be necessary. Glucocorticoids for prevention of pulmonary edema should be applied restrictively. Prophylactic antibiotics are not recommended. In severe ARDS, extracorporeal membrane oxygenation (ECMO) can be considered. Treatment is mainly symptom oriented. New and promising therapies are in development. [ABSTRACT FROM AUTHOR]

• Whole-body sarin exposure to a low concentration of 0.52 μg/L was sufficient in inducing pin-point pupils. • Whole-body sarin exposure leads to ocular surface histopathological lesions in a dose-response manner. • Topical 1 μg VX exposure induces a corneal histopathological damage while anti-muscarinic treatments alleviate this insult. Eye exposure to organophosphate (OP) chemical warfare irreversible acetylcholinesterase inhibitors, results in long-term miosis and impaired visual function. In contrast to the well-documented miotic and ciliary muscle spasm observed following chemical warfare, OP ocular exposure, little is known regarding the ocular surface histopathological insult. The aim of the present study was to determine the degree of the ocular surface insult following sarin or VX ocular exposure and to evaluate potential anti-cholinergic treatments in counteracting this insult. Rats that were whole body exposed to various sarin concentrations (0.049–43 μg/L; 5 min exposure), showed a dose-dependent miotic response and light reflex impairment. Following whole body sarin exposure, a dose dependent ocular surface histopathological insult was developed. A week following exposure to a low concentration of 0.05 μg/L, conjunctival pathology was observed, while corneal insult was noticed only following exposure to a concentration of 0.5 μg/L and above. Both tissues presented poorer outcomes when exposed to higher sarin concentrations. In contrast, eyes topically exposed to 1 μg sarin demonstrated no ocular insult a week following exposure. On the contrary, topical exposure to 1 μg VX resulted in a significant corneal insult. Anticholinergic treatments such as 0.1% atropine or 2% homatropine, given shortly following VX exposure, counteracted this insult. The results of this study show that not only do anti-cholinergic treatments counteract the miotic response, but also prevent the histopathological insult observed when given shortly following OP exposure. [ABSTRACT FROM AUTHOR]

Since the introduction of a benchtop vacuum ultraviolet (VUV) absorption spectroscope with an increased wavelength range towards to the high energetic ultraviolet radiation, gas chromatography coupled to VUV has been proven a powerful tool in several fields of application such as petroleomics, permanent gas analytic, pesticide analytic and many more. In this study, the potential of GC-VUV for investigations was examined, focusing on drug- and explosive precursors as well as chemical warfare simulants. The ability of VUV absorption spectra to differentiate isomers is presented, among others for nitroaromatics. In addition, the limit of detection for target compounds was determined to 0.7 ng absolute on column. Furthermore, non-negative matrix factorization (NMF) was successfully implemented as alternative deconvolution approach and evaluated for the deconvolution of unknown substances. In comparison, the spectral library-based deconvolution was applied to a standard mixture and a simulated case study. The results reveal that the NMF is a useful additional tool for deconvolution because, unlike library-based deconvolution, it allows to investigate unknown substances as well. Unlabelled Image • Vacuum ultraviolet absorption spectroscopy of drug- and explosive precursors • Deconvolution of co-eluting substances • Evaluation of non-negative matrix factorization for deconvolution • Comparison of spectral-based deconvolution and non-negative matrix factorization [ABSTRACT FROM AUTHOR]

Acetylcholinesterase (AChE) plays an important role in the therapy of Alzheimer's disease and in the detection of pesticides such as organophosphates which are also widely used in chemical warfare. The aim of this study is the physicochemical and kinetic characterization of brain and muscle ChE from Danio rerio (Zebrafish). Optimal activity was found for brain ChE at alkaline pH 9.0 at 30 °C, and for muscle ChE at alkaline pH 8.5 at temperatures between 20 °C and 35 °C. The apparent kinetic constants, K m app and V max app , for brain ChE were determined as 0.191 ± 0.024 mM and 0.566 ± 0.028 U/mg protein, and for muscle ChE as 0.230 ± 0.030 mM and 0.677 ± 0.039 U/mg protein. Both brain and muscle ChE showed inhibition at high substrate concentrations. Brain and muscle ChE showed IC50 values for physostigmine of 0.61 μM and 0.37 μM, respectively. The ChE activity in brain was significantly inhibited by BW254c51 in all concentrations tested, but not by Iso-OMPA, while muscle ChE presented a moderate decrease (13 to 29%) in the activity values, indicating that BuChE is present. Unlabelled Image • Cholinesterases in adult D. rerio are tissue specific. • Adult D. rerio brain/muscle cholinesterases have distinct specificity to inhibitors. • Adult D. rerio muscle shows acetylcholinesterase and butyrilcholinesterase activity. [ABSTRACT FROM AUTHOR]

Chemical warfare (CW) agent simulants are used in laboratory experiments to study the combustion characteristics of CW agents due to their high toxicity. A crucial CW agent simulant with a chemical structure similar to the deadly nerve agent Sarin (GB) is diisopropyl methylphosphonate (DIMP), an organophosphate compound (OPC). In this study, the high-temperature oxidation of DIMP is investigated in a shock tube at temperatures between 1440 K and 1710 K and a pressure of 1–2 atm. The carbon monoxide mole fraction time histories near 4.9 µm were obtained using laser absorption spectroscopy. The rate parameters for DIMP's H-abstraction reactions with O, and OH radicals were determined using molecular simulations. The rates of reactions involving smaller phosphorous species were also calculated at the CBS-QB3 level. These reactions along with the isopropanol sub-mechanism from the literature were added to the LLNL model to obtain an improved chemical kinetic mechanism for DIMP. Since isopropanol was a major intermediate in DIMP decomposition, validations were conducted with CO time histories during the oxidation of isopropanol. The new model predicted CO during isopropanol oxidation reasonably well. Both the LLNL model and the model developed in this work could predict CO time histories during DIMP oxidation satisfactorily. To comprehend the CO formation pathways and sensitive reactions during DIMP oxidation, reaction path analysis and sensitivity analysis were also carried out. The reaction mechanism developed here will help in the design, development, and optimization of efficient, effective and secure CW destruction techniques. [ABSTRACT FROM AUTHOR]

Organophosphates are a worldwide threat because of their presence in agrochemicals and chemical warfare. Situations of misuse, apprehensions of prohibited chemicals (e.g. pesticides), undesired stockpiles and chemical attacks require effective measures for neutralization and removal. Herein, a green approach is shown by functionalizing the agricultural waste rice husk with amidoximes leading to heterogeneous catalysts that were applied in the degradation/scavenging of toxic organophosphates. In aqueous medium, the waste-derived catalyst was efficient in the catalytic neutralization of a phosphotriester (increments up to 1 × 104-fold), while allying important features: selective, recyclable and lead to less toxic products. Curiously, the amidoximated rice husk behaved as a scavenger in the aprotic polar solvents MeCN and acetone by covalently bonding to the phosphoryl moiety. Upon addition of water, this bond is broken and the phosphoryl liberated (hydrolyzed) to the aqueous medium. Thus, the scavenging process is reversible and can be used to remove toxic organophosphates. 31P nuclear magnetic resonance spectroscopy was crucial for confirming the overall mechanisms involved. In summary, a sustainable material was synthetized from a waste source and employed as catalyst and scavenger for eliminating threatening organophosphates. This is promising for assuring chemical security such as in chemical emergencies. [Display omitted] • Functionalization of the waste rice husk leads to a multifunctional material. • Toxic organophosphates can be catalytically neutralized towards less toxic products. • The amidoxime-based scavenger can remove organophosphates and regenerate after. • Cellulose-based biocatalysts present dual function. [ABSTRACT FROM AUTHOR]

The GIFT CBRN project (Generic Integrated Forensic Toolbox for chemical, biological, radiological and nuclear incidents), funded under the Seventh Framework Programme of the European Commission, has been set up to find solutions for investigating incidents involving CBRN agents. Regarding the forensic point of view, specific tools and procedures to assist forensic investigators to perform a crime scene investigation (CSI) and methodologies to enable the subsequent analysis of the evidences (contaminated with CBRN agents) seized at the crime scene have been developed. To validate the procedures and methods developed within this project and to test them, three field-exercises engaged with one type of agent at the time (i.e. a RN-agent, a B-agent or a C-agent) has been held. The Belgian Defence Laboratories (DLD) in collaboration with Royal Military Academy (RMA) and the National Institute of Criminalistics and Criminology (NICC) has organized the chemical field exercise in Belgium. CSI teams of the Belgian Federal Police (experienced in crime scene investigation, fingerprints and digital forensics but at the time of the exercise not trained to perform their activities in CBRN conditions), SIBCRA teams (experienced in the sampling and identification of CBRN agents in hazardous environments) and the Civil Protection (experienced in entering zones with potential chemical hazards in full individual protective equipment) were involved. Since those teams never worked together in CBRN conditions, the exercise was used to establish the first operating procedure for CSI and laboratory analysis for CBRN and forensic materials in Belgium. The main steps of the procedure applied during this filed-exercise are described is this manuscript. The first step was the reconnaissance performed to (i) identify/quantify the threat agent involved, (ii) to document the scene and (iii) to collect priority forensic evidences. The second step focused on the collection of other forensic evidences, the sampling of DNA traces and the revelation of fingerprints at the scene. The collection of CBRN agents was performed during step 3. Step 4 concentrated on the decontamination and transport of evidences and traces sampled in the contaminated zone. The revelation of fingerprints in a glovebox (step 5) was finally demonstrated. In conclusion, this field-exercise was an opportunity for the different Belgium services to work together, to learn from each other, and to work towards the establishment of a national operating procedure to manage investigations in CBRN conditions. [ABSTRACT FROM AUTHOR]

Abstract Sensors in buildings are used for a wide variety of applications such as monitoring air quality, contaminants, indoor temperature, and relative humidity. These are used for accessing and ensuring indoor air quality, and also for ensuring safety in the event of chemical and biological attacks. It follows that optimal placement of sensors become important to accurately monitor contaminant levels in the indoor environment. However, contaminant transport inside the indoor environment is governed by the indoor flow conditions which are affected by various uncertainties associated with the building systems including occupancy and boundary fluxes. Therefore, it is important to account for all associated uncertainties while designing the sensor layout. The transfer operator based framework provides an effective way to identify optimal placement of sensors. Previous work has been limited to sensor placements under deterministic scenarios. In this work we extend the transfer operator based approach for optimal sensor placement while accounting for building systems uncertainties. The methodology provides a probabilistic metric to gauge coverage under uncertain conditions. We illustrate the capabilities of the framework with examples exhibiting boundary flux uncertainty. Highlights • A methodology accounting for building uncertainties during optimal sensor placement is presented. • This is based on contaminant transport analysis using the fast and accurate Perron-Frobenious operator. • The method is illustrated for two and three dimensional building geometries while accounting for various constraints associated with sensor placements. • This framework is useful for applications involving indoor air quality, chemical and biological warfare and transmission of infectious diseases. [ABSTRACT FROM AUTHOR]

Abstract With the tangible threat posed by the release of chemical and biological warfare (CBW) agents, detection of airborne pathogens is a critical military and security concern. Recent air sampling techniques developed for biocollection take advantage of Electrowetting on Dielectric (EWOD) to recover material, producing highly concentrated droplet samples. Bespoke EWOD-based digital microfluidics platforms are very well suited to take full advantage of the microlitre concentrated droplet resulting from this recovery process. In this paper we present a free-standing, fully automated DMF platform for immunoassay. Using this system, we demonstrate the automated detection of four classes of CBW agent simulant biomolecules and organisms each representing credible threat agents. Taking advantage of the full magnetic separation process with antibody-bound microbeads, rapid and complete separation of specific target antigen can be achieved with minimal washing steps allowing for very rapid detection. Here, we report clear detection of four categories of antigens achieved with assay completion times of between six and ten minutes. Detection of HSA, Bacillus atrophaeus (BG spores), MS2 bacteriophage and Escherichia coli are demonstrated with estimated limit of detection of respectively 30 ng ml-1, 4 × 104 cfu ml-1, 106 pfu ml-1 and 2 × 107 cfu ml-1. The fully-integrated portable platform described in this paper is highly compatible with the next generation of electrowetting-coupled air samplers and thus shows strong potential toward future in-field deployable biodetection systems and could have key implication in life-changing sectors such as healthcare, environment or food security. Highlights • Digital microfluidics (DMF) devices are seen as promising candidates to address the detection of aerosolised pathogens. • A free-standing, automated DMF platform for immunoassay was developed for direct detection of biomolecules and organisms. • For the first time using a DMF system, rapid detection of four classes of CBW agent simulants was demonstrated. • Rapid detection has been achieved with assay times between six minutes and ten minutes. Bullet point. • Fully automated detection of E. Coli, BG, MS2 and HSA has been demonstrated as a proof of concept for versatile biodetection. [ABSTRACT FROM AUTHOR]

Abstract Gold nanoparticles (AuNPs)-embedded paper was coupled with ion-transmission mass spectrometry (MS) to enable the highly sensitive detection of chemical warfare agent (CWA) simulants in solutions. With the assistance of a low-temperature plasma (LTP) probe, we found that AuNPs were capable to enhance the ionization efficiencies of target analytes, with MS signal intensities surprisingly undergone an 800-fold increase under optimized conditions. The interaction between AuNPs and the radiofrequency electromagnetic field was believed to promote the desorption/ionization process, resulting in the unusual signal enhancement phenomenon. Based on this finding, we established a method for the rapid analysis of two simulants of nerve agents, dimethyl methylphosphonate (DMMP) and diisopropyl methylphosphonate (DIMP), with a dynamic range from 0.5 ng/mL to 100 ng/mL and detection limits of 0.1 ng/mL and 0.3 ng/mL, respectively. As sample pretreatments have been eliminated, the developed strategy is particularly promising for the on-site detection of CWAs considering its simple and rapid analytical workflow. Graphical abstract fx1 Highlights • AuNPs coupled with a low-temperature plasma could greatly enhance the MS responses of chemical warfare agent simulants. • Activated AuNPs promoted analyte desorption and ionization. • A fast and robust method for quantitation of DMMP and DIMP was developed, with detection limits as low as 0.1 ng/mL obtained. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Two undemanding methods were used to prepare TiO 2 /GO nanocomposites. • GO addition increased adsorption capacity of the composites. • GO addition resulted in an enhanced reactive dissociation of DMMP. • Redox state of GO is crucial parameter for adsorption and degradation. Abstract Two water-based methods were used to produce TiO 2 /graphene oxide (GO) nanocomposites with 1 and 2 wt.% GO. Both procedures exclude the use of organometallic precursors, as well as the high-pressure and high-temperature treatments, which facilitate pure and energy efficient synthesis amenable for larger scale synthesis. Nanocomposites with narrow (<10 nm) and long spindle-like (<100 nm) TiO 2 nanoparticles supported on GO flakes were obtained (TiO 2 /GO), and their properties for reactive destruction of the organophosphorus simile chemical warfare agent (CWA) dimethyl methylphosphonate (DMMP) were investigated by in situ DRIFTS spectroscopy. Both synthesis procedures yielded highly reactive nanocomposites with markedly different properties compared to similarly prepared pure TiO 2 nanoparticles. GO also induced morphology and texture changes, which were observed to have a significant impact on the adsorption and reactivity of the nanocomposites, and which were strongly related to synthesis procedure. In particular, the reduction state of GO, as measured by Raman spectroscopy, was observed to play a major role for the reactivity of the TiO 2 /GO nanocomposites. [ABSTRACT FROM AUTHOR]

The Scientific Advisory Board (SAB) of the Organisation for the Prohibition of Chemical Weapons (OPCW) has provided advice on the long-term storage and stability of samples collected in the context of chemical weapons investigations. The information they compiled and reviewed is beneficial to all laboratories that carry out analysis of samples related to chemical warfare agents and is described herein. The preparation of this report was undertaken on request from the OPCW Director-General. The main degradation products for chemicals on the Schedules in the Annex on Chemicals of the Chemical Weapons Convention are tabulated. The expertise of the 25 scientists comprising the SAB, a review of the scientific literature on environmental and biomedical sample analysis, and answers to a questionnaire from chemists of nine OPCW Designated Laboratories, were drawn upon to provide the advice. Ten recommendations to ensure the long-term storage and stability of samples collected in relation to the potential use of chemical weapons were provided and are repeated here for the consideration of all laboratories worldwide. [ABSTRACT FROM AUTHOR]

Background Sulfur mustard (SM) is a potent blistering chemical warfare agent, which was first used in 1917. Despite the Chemical Weapons Convention, a use was recently reported in Syria in 2015. This emphasizes the importance to develop countermeasures against chemical warfare agents. Despite intensive research, there is still no antidote or prophylaxis available against SM. Methods The newly developed SM-resistant keratinocyte cell line HaCaT/SM was used to identify new target structures for drug development, particularly the adaptations in protective measures against oxidative stress. For this purpose, glutathione (GSH) and NAD(P)H levels, the effect of glutathione S-transferase (GST) inhibition as well as activation and expression of Nrf2, GST, glutamate cysteine ligase (GCL) and glutathione-disulfide reductase (GSR) as well as multi-drug resistance (MDR) proteins 1, 3 and 5 were investigated. Results The HaCaT/SM cells showed not only a better survival after treatment with SM or cytostatic drugs, but also hydrogen peroxide (H 2 O 2 ). They exhibit more GSH even after SM treatment. Nrf2 levels were significantly lower. Inhibition of GST led to significantly decreased, activation to slightly higher IC 50 values after SM treatment and a lower expression of GST was observed. The cells also expressed less GCLC and GSR. Expression of MDR1, MDR3 and MDR5 was higher under control conditions, but less stimulated by SM treatment. An increased NADP + /NADPH ratio as well as higher NAD + levels were shown. Conclusion In summary, an improved response of the resistant cell line to oxidative stress was observed. The underlying mechanisms are elevated GSH levels as well as lower expression of Nrf2 and its targets GCLC and GST as well as GSR and MDR1, MDR3 and MDR5. GST is an especially interesting target because its inhibition already induced a significant SM sensitivity. SM resistance also caused redox equivalent level differences. Taken together, these findings provide further insight into the mechanism of SM resistance and may open a window for novel therapeutic targets in SM therapy. [ABSTRACT FROM AUTHOR]

In August 2003, 44 victims were poisoned by chemical warfare agents (CWAs) leaked from five drums that were excavated at a construction site in Qiqihar, Northeast China. The drums were abandoned by the former Japanese imperial army during World War II and contained a mixture of Sulfur mustard (SM) and Lewisite. We carried out a total of six regular check-ups between 2006 and 2014, and from 2008 we added neurological evaluations including neuropsychological test and autonomic nervous function test in parallel with medical follow-up as much as was possible. Severe autonomic failure, such as hyperhidrosis, pollakiuria, diarrhoea, diminished libido, and asthenia appeared in almost all victims. Polyneuropathy occurred in 35% of the victims and constricted vision occurred in 20% of them. The rates of abnormal response on cold pressor test (CPT), active standing test (AST), Heart rate variability (CV R-R ), performed in 2014, were 63.1%, 31.6%, and 15.9%, respectively. On neuropsychological testing evaluated in 2010, a generalized cognitive decline was observed in 42% of the victims. Memories and visuospatial abilities were affected in the remaining victims. Finally, a 17-item PTSD questionnaire and the Beck Depression Inventory evaluated in 2014 revealed long-lasting severe PTSD symptoms and depression of the victims. Our findings suggest that an SM/Lewisite compound have significant adverse consequences directly in cognitive and emotional network and autonomic nervous systems in the brain. [ABSTRACT FROM AUTHOR]

The skin is highly sensitive to the chemical warfare agent in mustard gas, sulfur mustard (SM) that initiates a delayed injury response characterized by erythema, inflammation and severe vesication (blistering). Although SM poses a continuing threat, used as recently as in the Syrian conflict, no mechanism-based antidotes against SM are available. Recent studies demonstrated that Transient Receptor Potential Ankyrin 1 (TRPA1), a chemosensory cation channel in sensory nerves innervating the skin, is activated by SM and 2‐chloroethyl ethyl sulfide (CEES), an SM analog, in vitro , suggesting it may promote vesicant injury. Here, we investigated the effects of TRPA1 inhibitors, and an inhibitor of Calcitonin Gene Related Peptide (CGRP), a neurogenic inflammatory peptide released upon TRPA1 activation, in a CEES-induced mouse ear vesicant model (CEES-MEVM). TRPA1 inhibitors (HC-030031 and A-967079) and a CGRP inhibitor (MK-8825) reduced skin edema, pro-inflammatory cytokines (IL-1β, CXCL1/KC), MMP-9, a protease implicated in skin damage, and improved histopathological outcomes. These findings suggest that TRPA1 and neurogenic inflammation contribute to the deleterious effects of vesicants in vivo , activated either directly by alkylation, or indirectly, by reactive intermediates or pro-inflammatory mediators. TRPA1 and CGRP inhibitors represent new leads that could be considered for validation and further development in other vesicant injury models. [ABSTRACT FROM AUTHOR]

The chemical warfare agent sulfur mustard (SM) can cause long-term health effects that may occur even years after a single exposure. The underlying pathophysiology is unknown, but epigenetic mechanisms are discussed as feasible explanation. “Epigenetics” depicts regulation of gene function without affecting the DNA sequence itself. DNA-methylation and covalent histone modifications (methylation or acetylation) are regarded as important processes. In the present in vitro study using early endothelial cells (EEC), we analyzed SM-induced DNA methylation over time and compared results to an in vivo skin sample that was obtained approx. one year after an accidental SM exposure. EEC were exposed to low SM concentrations (0.5 and 1.0 μM). DNA methylation and histone acetylation (H3-K9, H3-K27, H4-K8) or histone di-methylation (H3-K9, H3-K27, H3-K36) were investigated 24 h after exposure, and after 2 or 4 additional cell passages. The human skin sample was assessed in parallel. SM had only some minor effects on histone modifications. However, a significant and pronounced increase of DNA methylation was detected in the late cell passages as well as in the skin sample. Our results indicate that SM does indeed cause epigenetic modifications that appear to persist over time. [ABSTRACT FROM AUTHOR]

Synthetic toxic chemicals (toxicants) and biological poisons (toxins) have been developed as chemical warfare agents in the last century. At the time of their initial consideration as chemical weapon, only restricted knowledge existed about their mechanisms of action. There exist two different types of acute toxic action: nonspecific cytotoxic mechanisms with multiple chemo-biological interactions versus specific mechanisms that tend to have just a single or a few target biomolecules. TRPV1- and TRPA-receptors are often involved as chemosensors that induce neurogenic inflammation. The present work briefly surveys classes and toxicologically relevant features of chemical warfare agents and describes mechanisms of toxic action. [ABSTRACT FROM AUTHOR]

Highly sensitive chemical warfare agents (CWAs) detection is demanded against the usage of the CWAs for war or terrorism aims. A dimethyl methylphosphonate (DMMP), simulant for sarin, monitoring sensor based on a homemade wireless-electrodeless quartz crystal microbalance with dissipation (QCM-D) was developed. With this noncontact configuration, deterioration of the sensing ability cause by the electrodes and drilling on the gas chamber for wire lead was avoided. Nano-structured hollow ball-like indium oxide (In 2 O 3 ) was synthesized using a facile hydrothermal method and then decorated with cubic gold particles (In 2 O 3 -Au). Both of them were applied as the sensing films to detect DMMP. The In 2 O 3 -Au based QCM-D sensor exhibited 2.1 Hz/ppm to DMMP range from 5 ppm to 50 ppm, which was 400% higher compared to the undecorated one. Moreover, with the simultaneously monitored dissipation value, desorption processes of DMMP was further investigated and the overshoot that appear in some researches was explained in terms of visco-elastic variations in mechanical stiffness. The results suggest that the wireless-electrodeless QCM-D could be a promising strategy for observation of materials under dynamic conditions. [ABSTRACT FROM AUTHOR]

In recent years, people pay more attention to the protection against chemical warfare agents, due to the increase in the probability of usage of these chemical warfare agents in wars or terrorist attacks. In this work, MgO nanoparticles were in-situ growth on the surface of poly(m-phenylene Isophthalamide) (PMIA) forming a flexible and breathable fabric for the detoxification of mustard gas surrogate. The as-prepared nanofibrous membrane possesses a “flower-like” structure of which endows not only increase the specific surface area of the composite but also prevent the agglomeration of the MgO nanoparticles. The detoxification ability of the PMIA@MgO nanofibrous fabric was demonstrated by gas chromatography-mass spectrometer (GC–MS). It is found that after 20 h of reaction time, 70.56% of the mustard gas surrogate have been decomposed. [ABSTRACT FROM AUTHOR]

The Baltic Sea is a severely disturbed marine ecosystem that has previously been used as a dumping ground for Chemical Warfare Agents (CW). The presence of unexploded underwater ordnance is an additional risk factor for offshore activities and an environmental risk for the natural resources of the sea. In this paper, the focus is on descriptions of the marine habitat based on the observations arising from studies linked to the CHEMSEA, MODUM and DAIMON projects. Investigated areas of Bornholm, Gotland and Gdańsk Deeps are similarly affected by the Baltic Sea eutrophication, however, at depths greater than 70 m several differences in local hydrological regimes and pore-water heavy metal concentrations between those basins were observed. During the lifespan of presented studies, we were able to observe the effects of Major Baltic Inflow, that started in December 2014, on local biota and their habitats, especially in the Bornholm Deep area. Reappearance of several meiofauna taxa and one macrofauna specimen was observed approximately one year after this phenomenon, however it's ecological effects already disappeared in March 2017. According to our findings and to the EUNIS Habitat Classification, the three reviewed areas should be characterized as Deep Sea Muddy Sands, while the presence of suspicious bomb-like objects both beneath and on top of the sediments confirms their CW dumpsite status. [ABSTRACT FROM AUTHOR]

Two highly sensitive probes bearing a nucleophilic imine moiety have been utilized for the selective detection of chemical warfare agent (CWA) mimics. Diethyl chlorophosphate (DCP) was used as mimic CWAs. Both iminocoumarin-benzothiazole-based probes not only demonstrated a remarkable fluorescence ON-OFF response and good recognition, but also exhibited fast response times (10 s) along with color changes upon addition of DCP. Limits of detection for the two sensors 1 and 2 were calculated as 0.065 μ M and 0.21 μ M, respectively, which are much lower than most other reported probes. These two probes not only show high sensitivity and selectivity in solution, but can also be applied for the recognition of DCP in the gas state, with significant color changes easily observed by the naked eye. [ABSTRACT FROM AUTHOR]

We report a novel, simple, and sensitive colorimetric assay by the in situ formation of gold nanoparticles in the presence of acetylcholinesterase and acetylthiocholine for the detection of chemical warfare agent simulant, 1,5-bis(4-allyldimethylammoniumphenyl)pentan-3-one dibromide (BW284c51). In this method, we used a low concentration (7 mM) of sodium borohydride to produce stable gold nanoparticles by the enzymatic hydrolysis of acetylcholinesterase (AChE). The product of enzymatic reaction thiocholine acts as a stabilizing agent. UV–visible spectra and transmission electron microscopy confirmed that the formation of stable gold nanoparticles in the presence of enzymatically produced thiol molecule. The in situ formation of gold nanoparticles was hindered by the addition of AChE inhibitor, BW284c51, which irreversibly blocked the active sites and decreased the production of thiol molecule. This, in turn, caused a decrease in the absorption peak of the nanoparticles at 520 nm. The proposed method achieved a limit of detection of 0.77 × 10 −9 M. The probe was also successfully used for determination of chemical warfare agent simulant, BW284c51 in spiked real water samples. [ABSTRACT FROM AUTHOR]

Because of the highly toxic properties of chemical warfare agents (CWA), an effective technology for the deactivation/detoxification of CWAs is desperately needed. Due to the safety issues involved in treating CWAs, catalytic conversion into (an)other non-toxic or less toxic material is suggested as one of the most favorable routes for their treatment. In this respect, many materials including zeolites, activated carbon, and metal oxides have been used as catalysts for the hydrolysis/methanolysis of the highly toxic organophosphate bonds of CWAs. However, the limited structural flexibility of these catalytic materials has been a hurdle to expanding detoxification on a large scale. A new option of using various porous materials for this application, including metal–organic frameworks (MOFs), has provided the potential for structural tailoring of the deactivation of CWAs. To discuss the potential of MOFs as deactivation/detoxification platforms for CWAs, we have initially described the structural pre-requisites for improving the catalytic activity of the MOF catalysts. A detailed explanation of the MOF catalysis and suitable examples are provided along with future perspectives and recommendations for such applications. We hope that this review will help provide a new roadmap for the scientists who are working in the area of heterogeneous catalytic approaches for the efficient degradation of CWAs. [ABSTRACT FROM AUTHOR]

A novel protocol for hydrolyzing phosphonothioate neurotoxins has been developed that uses a readily available, inexpensive and non-toxic molybdate (MoO 4 2− ). The target organophosphate is O,S -diethylphenyl phosphonothioate ( 1 ), a model compound that has served as an analog of the chemical warfare agent VX. Molybdate-mediated hydrolysis of 1 proceeds at room temperature (pH ∼ 7.5) and yields a relatively safe phosphonate product through P-S specific scission. This is the first report of utilizing the molybdate, MoO 4 2− , to degrade an organophosphate neurotoxin with turnover. A ΔS ‡ of −81.5 J/mol·K (−19.5 cal/mol·K) indicates a bimolecular process, and 18 O-labeling studies show no oxygen exchange of 1 throughout the hydrolysis by MoO 4 2− ( aq ). We hypothesize primarily the monomeric molybdate is the active species at pH 7.5 where a S N 2(P) mechanism takes place. Density functional theory methods suggest the molybdate oxoanion serves as the nucleophile to attack phosphonothioate 1 to form a molybdate-phosphonate anhydride that subsequently hydrolyzes to the starting molybdate and phenylethyl phosphonate. [ABSTRACT FROM AUTHOR]

Organophosphates (OPs) are highly neurotoxic compounds and certain OP-compounds are also exploited as a weapon of mass destruction and chemical warfare in terrorist attacks. Available prophylactic and post-exposure treatments are less effective and also have serious side-effects. Thus, there is a dire need to develop effective and safe prophylactic agent(s) against OP-poisoning. Human Paraoxonase 1 (hPON1) can hydrolyze a wide range of OP molecules and can be developed as an effective and safe prophylactic agent. Thus, there is a dire need in the art to develop variant(s) of rhPON1 that not only possess 'good' OP-hydrolyzing activity but also have improved pharmacokinetic properties. In this report, we describe the characterization of the fused hPON1 (FHP) variant that not only exhibit enhanced in vivo pharmacokinetic properties but also delay / prevent the symptoms of OP-poisoning and prevents OP-induced mortality in rats. • rhPON1 can be developed as prophylactic against OP poisoning. • 3dHSA fused rhPON1 (FHP) is developed with improved half-life. • In vivo pharmacokinetic and prophylactic protection efficacy are determined in rat. • FHP provide prophylactic protection against paraoxon-poisoning. [ABSTRACT FROM AUTHOR]

The associated particle (AP) technique has recently been used with a high-purity germanium γ -ray spectrometer to assess its capability to improve field identification of recovered chemical warfare (CW) materiel through prompt gamma-ray neutron activation analysis (PGNAA) measurements. A particularly challenging pair of CW agents commonly found in recovered munitions are phosgene (CG) and cyanogen chloride (CK), which have two of three elements in common, i.e. chlorine and carbon, but differ in the third being either oxygen or nitrogen. The detection of both latter elements is complicated by high oxygen concentration in the field environment which interferes with the small signal produced from the chemical agents. The matter is further complicated by the precautionary field practice of overpacking recovered munitions with vermiculite in larger steel multiple round containers (MRCs), which places additional oxygen-rich material in contact with the munition while further attenuating an already weak signal emitted from the munition center. This work reports quantitative results from realistic field measurements of CG and CK simulants in mock 4.2-inch (11 cm) mortar rounds overpacked with vermiculite in a large MRC. Results obtained with the AP technique are compared to those obtained with the traditional PGNAA approach for both overpacked- and bare-munition measurements. The AP technique is shown to provide a much more confident discrimination between the two chemicals, particularly for the more challenging field-relevant overpacked measurements, where a significant gain in sensitivity to all the key elements (chlorine, carbon, nitrogen and oxygen) is achieved. • Associated Particle (AP) technique allows better discrimination between phosgene and cyanogen chloride in recovered chemical munitions. • Improved prompt gamma-ray neutron activation analysis (PGNAA) sensitivity to key elements C, N, O, and Cl with AP technique. • Achieved success for field-relevant measurements of overpacked munitions in multiple round containers (MRCs). • Strong suppression of background oxygen enables better discriminability and sensitivity. [ABSTRACT FROM AUTHOR]

Two sets of zinc-iron and copper-iron mixed (hydr)oxides were prepared by a simple co-precipitation method. Either nitrate or chloride was a source of the metals. The decontamination ability of the materials was tested in closed vials saturated with vapors of 2-chloroethyl ethyl sulfide (CEES) or dimethyl chlorophosphate (DMCP), a blister agent and a nerve agent surrogate, respectively. In both cases, the weight uptakes on the mixed oxides were superior to the ones reported for the pure metal oxides or hydroxides. When exposed to CEES for 5 days, zinc-iron (hydr)oxides show much higher activity than the copper-iron ones. The products of reactions in the vessel headspace were investigated by GC/MS and on the surface by FTIR. Ethyl vinylsulfide and chloromethane are the main products of the reactive adsorption of CEES and DMCP, respectively. This indicates that CEES is mainly degraded by dehydrochlorination and DMCP- by hydrolysis. [ABSTRACT FROM AUTHOR]

Prevention of the penetration of toxic agents through the skin is crucial for both military troops and civilian populations. We have developed a novel topical skin protectant (TSP), coded as IB1 and commercially available as Dermostyx protective solution (Rekah Pharm, Israel). The formulation afforded significant protection against chemical warfare agents such as sulfur mustard (SM) and VX (2LD50), pesticides such as parathion and irritants such as acrolein. The efficacy of the protectant was evaluated in the pig model using clinical, histological and biochemical monitoring. A single topical application prior to exposure to the toxic agents reduced significantly the size and severity of skin lesions and ameliorated or prevented systemic clinical symptoms. The barrier properties of IB1 are immediate upon application and remain effective for at least 12 h. It is absorbed into the stratum corneum of the skin and remains there until rinsing with water, yet the ingredients are not absorbed into the body. The formulation is a hydrophilic water-based solution, composed of magnesium sulfate and glycerin that are widely used in cosmetic and medicine, and was shown to be safe in preclinical and in Phase I clinical studies. The suggested mode of action is based on the unique interaction of glycerin with the stratum corneum, changing its properties to hydrophilic and on the “salting out” effect of magnesium sulfate. The expected use of the TSP is by application on exposed skin areas and sensitive skin sites (e.g. armpits, groin, waist), when necessary. A quantity of 10 ml is sufficient for one application covering approximately 20% of the body surface area. The formulation was approved for human use by the Israel Ministry of Health and a CE mark certificate in Europe has been recently issued (Class I). Dermostyx has been adopted by the IDF and first responders as a skin protectant for special needs. [ABSTRACT FROM AUTHOR]

The high number of annual fatalities following suicidal poisoning by organophosphorus (OP) pesticides and the recent homicidal use of the chemical warfare nerve agent sarin against civilian population in Syria underlines the continuous threat by these highly toxic agents. The need for an effective treatment of OP poisoning resulted in the implementation of a combination therapy with the muscarinic receptor antagonist atropine and an oxime for the reactivation of OP-inhibited acetylcholinesterase (AChE). Since the invention of the first clinically used oxime pralidoxime (2-PAM) in the 1950s ongoing research attempted to identify more effective oximes. In fact, several thousand oximes were synthesized in the past six decades. These include charged and non-charged compounds, mono- and bispyridinium oximes, asymmetric oximes, oximes with different substitutes and more recently non-oxime reactivators. Multiple in vitro and in vivo studies investigated the potential of oximes to reactivate OP-inhibited AChE and to reverse OP-induced cholinergic signs. Depending on the experimental model, the investigated species and the tested OP largely variable results were obtained by different laboratories. These findings and the inconsistent effectiveness of oximes in the treatment of OP-pesticide poisoned patients led to a continuous discussion on the value of oximes. In order to provide a forward-looking evaluation of the significance of oximes in OP poisoning multiple aspects, including intrinsic toxicity, in vitro reactivation potency, efficacy and pharmacokinetics, as well as the impact of the causative OP have to be considered. The different influencing factors in order to define the benefit and limitations of oximes in OP poisoning will be discussed. [ABSTRACT FROM AUTHOR]

Nanosized inorganic metal oxides, such as TiO 2 , ZnO, γ -Al 2 O 3 , are proposed as heterogeneous catalysts for the oxidative degradation of chemical warfare agents (CWA), particularly of organosulfur toxic agents, into oxidised products with reduced toxicity. The morphology, structural and textural properties of the catalysts were investigated. Furthermore, their catalytic properties were evaluated in the oxidative abatement of (2-chloroethyl)ethylsulfide, CEES, a simulant of sulfur mustard (blistering CWA). Their performance was also compared to a conventional decontamination powder and a commercial Nb 2 O 5 sample. The metal oxides powders were then employed in the active oxidative decontamination of CEES from a cotton textile substrate, mimicking a real contamination occurrence. Remarkable results in terms of abatement and degradation into desired products were recorded, achieving good conversions and decontamination efficiency with Nb 2 O 5 , TiO 2 and γ -Al 2 O 3 , under very mild conditions, with hydrogen peroxide (as aqueous solution or as urea-hydrogen peroxide adduct), at room temperature and ambient pressure. In the aim of a real on-field use, the potential environmental impact of these solids was also evaluated by bioluminescence toxicity tests on reference bacteria ( Photobacterium leiognathi Sh1), showing a negligible negative impact for TiO 2 , γ -Al 2 O 3 , and Nb 2 O 5 . A major biotoxic effect was only found for ZnO. [ABSTRACT FROM AUTHOR]

Novel Zr 4+ and Ge 4+ co-doped titanium dioxide (Zr–Ge–TiO 2 ) nanoparticles for photocatalytic degradation of Chemical Warfare Agents (CWAs) were prepared via a homogeneous precipitation method. Considering the volatilization of solvents, solubility to CWAs, and compatibility with sensitive equipments, hydrofluoroether (HFE) was first used as the dispersion solvent of suspension decontaminants. Here, Zr (5.02 wt%)–Ge (0.94 wt%)–TiO 2 with the specific surface area of 447.9 m 2 g −1 exhibited the best photocatalytic performance. This was dispersed in HFE-458 (HCF 2 CF 2 CH 2 OCF 2 CF 2 H) and HFE-6512 (HCF 2 CF 2 CF 2 CF 2 CH 2 OCF 2 CF 2 H) respectively. A new gas collection system was designed to study volatilization in the reaction process. As a result, HFE-6512 is more suitable as the dispersion solvent than HFE-458. The suspension prepared with HFE-6512 not only has higher degradation efficiency of HD, GD, VX, 2-CEES and DMMP, but also has fewer volatile agents. Under simulated sunlight irradiation, both the surface removal and the degradation efficiency of HD, GD, VX, 2-CEES and DMMP were over 99.95% after 37 min. The results show that this suspension has potential applications in decontamination of CWAs on sensitive equipment materials. With high absorbing efficiency of CWAs and their simulants, the designed gas collection system is reliable for the selection of solvents and improvement of disinfection effect. [ABSTRACT FROM AUTHOR]

On-spot monitoring of threat agents needs high sensitive instrument. In this study, a low-pressure photoionization mass spectrometer (LPPI-MS) was employed to detect trace amounts of vapor-phase explosives and chemical warfare agent mimetics under ambient conditions. Under 10-s detection time, the limits of detection of 2,4-dinitrotoluene, nitrotoluene, nitrobenzene, and dimethyl methyl phosphonate were 30, 0.5, 4, and 1 parts per trillion by volume, respectively. As compared to those obtained previously with PI mass spectrometric techniques, an improvement of 3–4 orders of magnitude was achieved. This study indicates that LPPI-MS will open new opportunities for the sensitive detection of explosives and chemical warfare agents. [ABSTRACT FROM AUTHOR]

[Display omitted] Organophosphate nerve agents are associated with assassination, terrorism and chemical warfare, but there has been slow progress in developing a broad-spectrum response to poisoning. For some nerve agents the oxime component of the therapy may not be effective, limiting the effectiveness of emergency treatment that is desperately needed. An alternative therapy may be possible based on accelerating enzyme (acetylcholinesterase) catalysis in unaffected adjacent enzymes. Herein we demonstrate a restoration of acetylcholinesterase activity in malathion-inhibited cell membrane preparations by the administration of functional nanoparticles. The molecularly imprinted polymer nanoparticles were designed to bind selectively to designated enzyme epitopes. Enzyme activity of membrane-bound acetylcholinesterase was measured in the presence of the organophosphate malathion and the selected nanoparticles. Enzymatic acceleration of the cholinesterase was observed at 162 ± 17 % the rate of erythrocyte ghosts without bound nanoparticles. This may restore sufficient acetylcholine hydrolysis to mitigate the effects of poisoning, offsetting the acetylcholine accumulation resulting from enzyme inhibition. [ABSTRACT FROM AUTHOR]

Three deep basins in the Baltic Sea were investigated within the framework of the CHEMSEA project (Chemical Munitions Search & Assessment), which aims to evaluate the ecological impact of chemical warfare agents dumped after World War II. Nematode communities, which comprise the most numerous and diverse organisms in the surveyed areas, were investigated as a key group of benthic fauna. One of the most successful nematode species was morphologically identified as Halomonhystera disjuncta (Bastian, 1865). The presence of this species, which is an active coloniser that is highly resistant to disturbed environments, may indicate that the sediments of these disposal sites are characterised by toxic conditions that are unfavourable for other metazoans. Moreover, ovoviviparous reproductive behaviour in which parents carry their brood internally, which is an important adaptation to harsh environmental conditions, was observed for specimens from Gdansk Deep and Gotland Deep. This reproductive strategy, which is uncommon for marine nematodes, has not previously been reported for nematodes from the Baltic Sea sediment. [ABSTRACT FROM AUTHOR]

Selective detection of sulfur mustard simulant, 2-chloroethyl ethyl sulfide ( CEES ) is performed using specifically designed pyridine appended Mg–porphyrazine complex ( 1 ). Interaction of CEES with pyridine units of 1 leads to perturbation/reduction in absorbance of the Q-band of 1 and the process is, thus, monitored using UV–vis spectroscopic method. Interestingly, treating the CEES- 1 solution with KMnO 4 solution results in reappearance of Q-band of 1 and allows reuse of 1 by simple filtration. The alkylating ability of CEES and KMnO 4 oxidation of CEES- 1 appears to be playing an important role in the detection/degradation process, thereby serving the dual purpose. The chemical sensing is then used as a platform for generating different input-based combinatorial and sequential molecular logic gate(s) allowing facile information processing and as an information security system in the form of a keypad lock. [ABSTRACT FROM AUTHOR]

Air quality has been an important issue in public health for many years. Sensing the level and distributions of impurities help in the control of building systems and mitigate long term health risks. Rapid detection of infectious diseases in large public areas like airports and train stations may help limit exposure and aid in reducing the spread of the disease. Complete coverage by sensors to account for any release scenario of chemical or biological warfare agents may provide the opportunity to develop isolation and evacuation plans that mitigate the impact of the attack. All these scenarios involve strategic placement of sensors to promptly detect and rapidly respond. This paper presents a data driven sensor placement algorithm based on a dynamical systems approach. The approach utilizes the finite dimensional Perron-Frobenius (PF) concept. The PF operator (or the Markov matrix) is used to construct an observability gramian that naturally incorporates sensor accuracy, location constraints, and sensing constraints. The algorithm determines the response times, sensor coverage maps, and the number of sensors needed. The utility of the procedure is illustrated using four examples: a literature example of the flow field inside an aircraft cabin and three air flow fields in different geometries. The effect of the constraints on the response times for different sensor placement scenarios is investigated. Knowledge of the response time and coverage of the multiple sensors aides in the design of mechanical systems and response mechanisms. The methodology provides a simple process for place sensors in a building, analyze the sensor coverage maps and response time necessary during extreme events, as well as evaluate indoor air quality. The theory established in this paper also allows for future work in topics related to construction of classical estimator problems for the sensors, real-time contaminant transport, and development of agent dispersion, contaminant isolation/removal, and evacuation strategies. [ABSTRACT FROM AUTHOR]

Magnetic hydrophilic–lipophilic balance (MHLB) hybrid resin was prepared by precipitation polymerization using N -vinylpyrrolidone (PVP) and divinylbenzene (DVB) as monomers and Fe 2 O 3 nanoparticles as magnetic material. These resins were successfully applied for the extraction of chemical warfare agents (CWAs) and their markers from water samples through magnetic dispersive solid-phase extraction (MDSPE). By varying the ratios of monomers, resin with desired hydrophilic–lipophilic balance was prepared for the extraction of CWAs and related esters of varying polarities. Amongst different composites Fe 2 O 3 nanoparticles coated with 10% PVP + 90% DVB exhibited the best recoveries varying between 70.32 and 97.67%. Parameters affecting the extraction efficiencies, such as extraction time, desorption time, nature and volume of desorption solvent, amount of extraction sorbent and the effect of salts on extraction were investigated. Under the optimized conditions, linearity was obtained in the range of 0.5–500 ng mL −1 with correlation ranging from 0.9911–0.9980. Limits of detection and limits of quantification were 0.5–1.0 and 3.0–5.0 ng mL −1 respectively with RSDs varying from 4.88–11.32% for markers of CWAs. Finally, the developed MDSPE method was employed for extraction of analytes from water samples of various sources and the OPCW proficiency test samples. [ABSTRACT FROM AUTHOR]

Children may be inherently more vulnerable than adults to the lethal effects associated with chemical warfare nerve agent (CWNA) exposure because of their closer proximity to the ground, smaller body mass, higher respiratory rate, increased skin permeability and immature metabolic systems. Unfortunately, there have only been a handful of studies on the effects of CWNA in pediatric animal models, and more research is needed to confirm this hypothesis. Using a stagewise, adaptive dose design, we estimated the 24 h median lethal dose for subcutaneous exposure to seven CWNA in both male and female Sprague-Dawley rats at six different developmental times. Perinatal (postnatal day [PND] 7, 14 and 21) and adult (PND 70) rats were more susceptible than pubertal (PND 28 and 42) rats to the lethal effects associated with exposure to tabun, sarin, soman and cyclosarin. Age-related differences in susceptibility were not observed in rats exposed to VM, Russian VX or VX. [ABSTRACT FROM AUTHOR]

We provide the first experimental demonstration of the transmission characteristics of holey and slotted photonic crystal waveguides (PCWs) in silicon-on-sapphire at mid-infrared wavelength of 3.43 μm. Devices are studied as a function of lattice constant to tune the photonic stop band across the single wavelength of the source laser. In the holey PCW, propagation losses less than 20 dB/cm are observed below the light line while more than 400 dB/cm propagation losses are observed above the light line, characteristic of the waveguiding behavior of photonic crystal line defect modes. Comparison between the holey and slotted PCWs with PCWs without low-index inclusions shows the higher sensitivity to refractive index changes in chemical sensing for the holey and slotted PCWs compared to the regular PCWs. Triethylphosphate (TEP), a chemical warfare simulant, was detected down to a concentration of 10 ppm (parts per million) with a 800 μm long holey PCW in gas phase via optical absorbance signature. [ABSTRACT FROM AUTHOR]

Diffusion cells are used to determine the penetration of chemicals through skin in vitro . The cells have a limited surface area defined by the edge of the donor chamber. Should the penetrant spread rapidly to this containment limit the penetration rate can be accurately quantified. For the hazard assessment of small droplets of toxic chemicals, such as cholinesterase inhibitors, limiting skin surface spread in vitro could lead to underestimation of percutaneous penetration and hence underestimation of systemic toxicity in vivo . The current study investigated the dependency of the percutaneous penetration of undiluted radiolabelled nerve agents (VX and soman (GD), 10 μl) on skin surface spread (pig and guinea pig) using Franz-type glass diffusion cells with an area available for diffusion of either 2.54 cm 2 or 14.87 cm 2 . Both VX and GD spread to the edge of the 2.54 cm 2 cells, but, not the 14.87 cm 2 cells over the study duration. Amounts of VX and GD penetrating pig and guinea pig skin in the 2.54 cm 2 cells were less than in the 14.87 cm 2 cells (except for GD under unoccluded conditions); however, penetration rates expressed per unit area were similar. Artificial limitation of skin surface spread in vitro does not impact percutaneous penetration in vitro as long as penetration is expressed in terms of mass per unit area. [ABSTRACT FROM AUTHOR]

The subject of the work is the use of differential mobility spectrometry (DMS) for the detection of chemical warfare agents (CWA). Studies were performed for mustard gas, i.e., bis(2-chloroethyl)sulfide (HD), sarin, i.e., O-isopropyl methylphosphonofluoridate (GB) and methyl salicylate (MS) used as test compounds. Measurements were conducted with two ceramic DMS analyzers of different constructions allowing the generation of an electric field with an intensity of more than 120 Td. Detector signals were measured for positive and negative modes of operation in a temperature range from 0 to 80 °C. Fragmentations of ions containing analyte molecules were observed for all tested compounds. The effective temperatures of fragmentation estimated on the basis of dispersion plots were equal from about 148 °C for GB to 178 °C for MS. It was found that values of separation voltage (SV) and compensation voltage (CV) at which the fragmentation of sample ions is observed may be the parameters improving the certainty of detection for different analytes. The DMS analyzers enabling the observation of ion fragmentation can be successfully used for effective CWA detection. [ABSTRACT FROM AUTHOR]