Reactivity of Dual-Use Decontaminants with Chemical Warfare Agents

Science.gov (United States)

2016-07-01

REACTIVITY OF DUAL-USE DECONTAMINANTS WITH CHEMICAL WARFARE AGENTS ECBC-TR-1384... Decontaminants with Chemical Warfare Agents 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Willis, Matthew P...extraction) of chemical warfare agents from materials. 15. SUBJECT TERMS GD HD Decontamination Hazard mitigation VX Chemical warfare agent Liquid-phase

Characterization of chemical agent transport in paints.

Science.gov (United States)

Willis, Matthew P; Gordon, Wesley; Lalain, Teri; Mantooth, Brent

2013-09-15

A combination of vacuum-based vapor emission measurements with a mass transport model was employed to determine the interaction of chemical warfare agents with various materials, including transport parameters of agents in paints. Accurate determination of mass transport parameters enables the simulation of the chemical agent distribution in a material for decontaminant performance modeling. The evaluation was performed with the chemical warfare agents bis(2-chloroethyl) sulfide (distilled mustard, known as the chemical warfare blister agent HD) and O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate (VX), an organophosphate nerve agent, deposited on to two different types of polyurethane paint coatings. The results demonstrated alignment between the experimentally measured vapor emission flux and the predicted vapor flux. Mass transport modeling demonstrated rapid transport of VX into the coatings; VX penetrated through the aliphatic polyurethane-based coating (100 μm) within approximately 107 min. By comparison, while HD was more soluble in the coatings, the penetration depth in the coatings was approximately 2× lower than VX. Applications of mass transport parameters include the ability to predict agent uptake, and subsequent long-term vapor emission or contact transfer where the agent could present exposure risks. Additionally, these parameters and model enable the ability to perform decontamination modeling to predict how decontaminants remove agent from these materials. Published by Elsevier B.V.

Development of an automated on-line pepsin digestion-liquid chromatography-tandem mass spectrometry configuration for the rapid analysis of protein adducts of chemical warfare agents

NARCIS (Netherlands)

Carol-Visser, J.; van der Schans, M.; Fidder, A.; Huist, A.G.; van Baar, B.L.M.; Irth, H.; Noort, D.

2008-01-01

Rapid monitoring and retrospective verification are key issues in protection against and non-proliferation of chemical warfare agents (CWA). Such monitoring and verification are adequately accomplished by the analysis of persistent protein adducts of these agents. Liquid chromatography-mass

Chemical Agents: Facts about Evacuation

Science.gov (United States)

... What CDC is Doing Blog: Public Health Matters Chemical Agents: Facts About Evacuation Format: Select One PDF [ ... on Facebook Tweet Share Compartir Some kinds of chemical accidents or attacks, such as a train derailment ...

Acute ecological toxicity and environmental persistence of simulants

Energy Technology Data Exchange (ETDEWEB)

Cataldo, D.A.; Ligotke, M.W.; McVeety, B.D.; Fellows, R.J.; Bolton, H. Jr.; Li, S.W.; Van Voris, P.; Wentsel, R.S.

1988-06-01

The objectives of these studies are to establish the comparative environmental behavior and chemical fate of chemical simulants. Laboratory studies were undertaken to establish: (1) deposition efficiency (deposition velocities, Vd) for receptor surfaces including plant foliage and soils; (2) dose/response relationships for important environmental components including plants and soil microflora; and (3) the environmental persistence of the simulants. Chemical agent simulants are employed for a range of testing and training activities where use of chemical agents is less than suitable from a safety and environmental standpoint. A variety of chemical simulant materials are used to simulate either nerve agents or blister agents. The following research describes the environmental effects and persistence of four simulants. These are the nerve agent stimulants diisopropyl methylphosphonate (DIMP), diisopropyl fluorophosphate (DFP), and bis (2-ethylhexyl) phosphonate (BIS), and the mustard stimulant 2-chloroethyl ethyl sulfide (CEES). The vapor pressures for DIMP, DFP, and CEES are relatively high, reported to be 0.17, 0.58 and 3.4 mm Hg, respectively; while that of BIS is substantially less at 5.8 /times/ 10/sup /minus/5/ mm Hg at 25/degree/C. The chemical characteristics of DFP and CEES are very similar to G/VX-agents and mustard, respectively, and are employed for materials evaluation under controlled conditions. However, their toxicity precludes their use in the environment. DIMP and BIS are currently used for testing in the open air. 3 figs., 3 tabs.

Country-specific chemical signatures of persistent environmental compounds in breast milk

DEFF Research Database (Denmark)

Krysiak-Baltyn, Konrad; Toppari, J.; Skakkebaek, N.E.

2010-01-01

for exposure of the foetus to such agents. Therefore, we undertook a comprehensive ecological study of 121 EDCs, including the persistent compounds dioxins, polychlorinated biphenyls (PCBs), pesticides and flame retardants, and non-persistent phthalates, in 68 breast milk samples from Denmark and Finland...

Chemical warfare agents. Classes and targets.

Science.gov (United States)

Schwenk, Michael

2018-09-01

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. Copyright © 2017 Elsevier B.V. All rights reserved.

Twitter web-service for soft agent reporting in persistent surveillance systems

Science.gov (United States)

Rababaah, Haroun; Shirkhodaie, Amir

2010-04-01

Persistent surveillance is an intricate process requiring monitoring, gathering, processing, tracking, and characterization of many spatiotemporal events occurring concurrently. Data associated with events can be readily attained by networking of hard (physical) sensors. Sensors may have homogeneous or heterogeneous (hybrid) sensing modalities with different communication bandwidth requirements. Complimentary to hard sensors are human observers or "soft sensors" that can report occurrences of evolving events via different communication devices (e.g., texting, cell phones, emails, instant messaging, etc.) to the command control center. However, networking of human observers in ad-hoc way is rather a difficult task. In this paper, we present a Twitter web-service for soft agent reporting in persistent surveillance systems (called Web-STARS). The objective of this web-service is to aggregate multi-source human observations in hybrid sensor networks rapidly. With availability of Twitter social network, such a human networking concept can not only be realized for large scale persistent surveillance systems (PSS), but also, it can be employed with proper interfaces to expedite rapid events reporting by human observers. The proposed technique is particularly suitable for large-scale persistent surveillance systems with distributed soft and hard sensor networks. The efficiency and effectiveness of the proposed technique is measured experimentally by conducting several simulated persistent surveillance scenarios. It is demonstrated that by fusion of information from hard and soft agents improves understanding of common operating picture and enhances situational awareness.

New Safety rule for Chemical Agents

CERN Multimedia

Safety Commission

2010-01-01

The following Safety rule has been issued on 08-01-2010: Safety Regulation SR-C Chemical Agents This document applies to all persons under the Director General’s authority. It sets out the minimal requirements for the protection of persons from risks to their safety and health arising, or likely to arise, from the effects of hazardous chemical agents used in any CERN activity. All Safety rules are available on the web pages.

Biomaterials for mediation of chemical and biological warfare agents.

Science.gov (United States)

Russell, Alan J; Berberich, Jason A; Drevon, Geraldine F; Koepsel, Richard R

2003-01-01

Recent events have emphasized the threat from chemical and biological warfare agents. Within the efforts to counter this threat, the biocatalytic destruction and sensing of chemical and biological weapons has become an important area of focus. The specificity and high catalytic rates of biological catalysts make them appropriate for decommissioning nerve agent stockpiles, counteracting nerve agent attacks, and remediation of organophosphate spills. A number of materials have been prepared containing enzymes for the destruction of and protection against organophosphate nerve agents and biological warfare agents. This review discusses the major chemical and biological warfare agents, decontamination methods, and biomaterials that have potential for the preparation of decontamination wipes, gas filters, column packings, protective wear, and self-decontaminating paints and coatings.

An Important Chemical Weapon Group: Nerve Agents

Directory of Open Access Journals (Sweden)

Hakan Yaren

2007-12-01

Full Text Available As a result of developing modern chemistry, nerve agents, which are one of the most important group of efficient chemical warfare agents, were developed just before Second World War. They generate toxic and clinical effects via inhibiting acetylcholinesterase irreversibly and causing excessive amounts of acetylcholine at cholinergic synapses in the body. Clinical symptoms are occurred as a result of affected muscarinic (stimulation of secretuar glands, miosis, breathing problems etc., nicotinic (stimulation of skeletal muscles, paralyse, tremors etc. and central nerve system (convulsions, loss of consciousness, coma etc. areas. In case of a nerve agent exposure, treatment includes the steps of ventilation, decontamination, antidotal treatment (atropine, oximes, diazepam and pyridostigmine bromide and supportive theraphy. Because of arising possibility of using chemical warfare agents due to current conjuncture of the world, medical staff should know about nerve agents, their effects and how to treat the casualties exposured to nerve agents. [TAF Prev Med Bull 2007; 6(6.000: 491-500

An Important Chemical Weapon Group: Nerve Agents

Directory of Open Access Journals (Sweden)

Hakan Yaren

2007-12-01

Full Text Available As a result of developing modern chemistry, nerve agents, which are one of the most important group of efficient chemical warfare agents, were developed just before Second World War. They generate toxic and clinical effects via inhibiting acetylcholinesterase irreversibly and causing excessive amounts of acetylcholine at cholinergic synapses in the body. Clinical symptoms are occurred as a result of affected muscarinic (stimulation of secretuar glands, miosis, breathing problems etc., nicotinic (stimulation of skeletal muscles, paralyse, tremors etc. and central nerve system (convulsions, loss of consciousness, coma etc. areas. In case of a nerve agent exposure, treatment includes the steps of ventilation, decontamination, antidotal treatment (atropine, oximes, diazepam and pyridostigmine bromide and supportive theraphy. Because of arising possibility of using chemical warfare agents due to current conjuncture of the world, medical staff should know about nerve agents, their effects and how to treat the casualties exposured to nerve agents. [TAF Prev Med Bull. 2007; 6(6: 491-500

Identification of chemical warfare agent with radiological measurements

International Nuclear Information System (INIS)

Liu Boxue; Li Yun; Ai Xianyun

2000-01-01

There are three non-destructive radiological methods for identification of warfare agents and TNT. Their principles and problems related were discussed. Portable isotopic neutron spectroscopy is based on the assay of key elemental composition (such as Cl, P, H, As, S, N) in chemical agents by neutron induced prompt gamma ray analysis. Hydrogen concentration measurement by means of using thermal neutron can be employed to identify chemical warfare agents and TNT that contains different hydrogen fraction. The calibration curves of thermal neutron count rate against hydrogen concentration were measured. X ray imagination system can be used to determine the internal structure of chemical bombs, there by to identify them. The radiological methods are very useful for identification of old chemical weapons abandoned by Japan Army during World War 2

Laser-based instrumentation for the detection of chemical agents

International Nuclear Information System (INIS)

Hartford, A. Jr.; Sander, R.K.; Quigley, G.P.; Radziemski, L.J.; Cremers, D.A.

1982-01-01

Several laser-based techniques are being evaluated for the remote, point, and surface detection of chemical agents. Among the methods under investigation are optoacoustic spectroscopy, laser-induced breakdown spectroscopy (LIBS), and synchronous detection of laser-induced fluorescence (SDLIF). Optoacoustic detection has already been shown to be capable of extremely sensitive point detection. Its application to remote sensing of chemical agents is currently being evaluated. Atomic emission from the region of a laser-generated plasma has been used to identify the characteristic elements contained in nerve (P and F) and blister (S and Cl) agents. Employing this LIBS approach, detection of chemical agent simulants dispersed in air and adsorbed on a variety of surfaces has been achieved. Synchronous detection of laser-induced fluorescence provides an attractive alternative to conventional LIF, in that an artificial narrowing of the fluorescence emission is obtained. The application of this technique to chemical agent simulants has been successfully demonstrated. 19 figures

Recent Advances in Decontamination of Chemical Warfare Agents

OpenAIRE

Abdul Wadood Khan; Sabna Kotta; Shahid Husain Ansari; Javed Ali; Rakesh Kumar Sharma

2013-01-01

The recent turmoil and volatile situation in many countries and the increased risk of terrorist activities have raised alarm bells for the field of defense against toxic chemical/materials. These situations poses threats to society as terrorists can take advantage of such situations to strike and cause public mayhem. A number of chemicals have the potential of being used as chemical warfare (CW) agents. CW agents could immediately kill or incapacitate the affected individuals even when they a...

Efficacy of liquid and foam decontamination technologies for chemical warfare agents on indoor surfaces.

Science.gov (United States)

Love, Adam H; Bailey, Christopher G; Hanna, M Leslie; Hok, Saphon; Vu, Alex K; Reutter, Dennis J; Raber, Ellen

2011-11-30

Bench-scale testing was used to evaluate the efficacy of four decontamination formulations on typical indoor surfaces following exposure to the liquid chemical warfare agents sarin (GB), soman (GD), sulfur mustard (HD), and VX. Residual surface contamination on coupons was periodically measured for up to 24h after applying one of four selected decontamination technologies [0.5% bleach solution with trisodium phosphate, Allen Vanguard Surface Decontamination Foam (SDF™), U.S. military Decon Green™, and Modec Inc. and EnviroFoam Technologies Sandia Decontamination Foam (DF-200)]. All decontamination technologies tested, except for the bleach solution, performed well on nonporous and nonpermeable glass and stainless-steel surfaces. However, chemical agent residual contamination typically remained on porous and permeable surfaces, especially for the more persistent agents, HD and VX. Solvent-based Decon Green™ performed better than aqueous-based bleach or foams on polymeric surfaces, possibly because the solvent is able to penetrate the polymer matrix. Bleach and foams out-performed Decon Green for penetrating the highly polar concrete surface. Results suggest that the different characteristics needed for an ideal and universal decontamination technology may be incompatible in a single formulation and a strategy for decontaminating a complex facility will require a range of technologies. Copyright © 2011 Elsevier B.V. All rights reserved.

Chemical Agents: Facts about Sheltering in Place

Science.gov (United States)

... What CDC is Doing Blog: Public Health Matters Chemical Agents: Facts About Sheltering in Place Format: Select ... What “sheltering in place” means Some kinds of chemical accidents or attacks may make going outdoors dangerous. ...

Portable Sensor for Chemical Nerve Agents and Organophosphorus Compounds

Science.gov (United States)

2015-08-18

as pesticides in crop, livestock, and poultry products and as chemical and biological warfare agents. As a result of the high toxicity and the...biomedical applications such as: tissue engineering, wound dressing materials, molecular imprinting, drug delivery, etc. In this experiment the hydrogel...agents have been exploited for use as pesticides in crop, livestock, and poultry products and as chemical and biological warfare agents. As a result of

Biomonitoring of exposure to chemical warfare agents

NARCIS (Netherlands)

Noort, D.; Schans, M.J. van der; Benschop, H.P.

2006-01-01

An overview is presented of the major methods that are presently available for biomonitoring of exposure to chemical warfare agents, i.e., nerve agents and sulfur mustard. These methods can be applied for a variety of purposes such as diagnosis and dosimetry of exposure of casualties, verification

Enzymatic Decontamination of Chemical Warfare Agents

National Research Council Canada - National Science Library

Raushel, Frank

2000-01-01

The primary objective of this research program is the development of a versatile enzyme-based system that is fully optimized for the decontamination, destruction, and detection of know chemical warfare agents...

[Decontamination of chemical and biological warfare agents].

Science.gov (United States)

Seto, Yasuo

2009-01-01

Chemical and biological warfare agents (CBWA's) are diverse in nature; volatile acute low-molecular-weight toxic compounds, chemical warfare agents (CWA's, gaseous choking and blood agents, volatile nerve gases and blister agents, nonvolatile vomit agents and lacrymators), biological toxins (nonvolatile low-molecular-weight toxins, proteinous toxins) and microbes (bacteria, viruses, rickettsiae). In the consequence management against chemical and biological terrorism, speedy decontamination of victims, facilities and equipment is required for the minimization of the damage. In the present situation, washing victims and contaminated materials with large volumes of water is the basic way, and additionally hypochlorite salt solution is used for decomposition of CWA's. However, it still remains unsolved how to dispose large volumes of waste water, and the decontamination reagents have serious limitation of high toxicity, despoiling nature against the environments, long finishing time and non-durability in effective decontamination. Namely, the existing decontamination system is not effective, nonspecifically affecting the surrounding non-target materials. Therefore, it is the urgent matter to build up the usable decontamination system surpassing the present technologies. The symposiast presents the on-going joint project of research and development of the novel decontamination system against CBWA's, in the purpose of realizing nontoxic, fast, specific, effective and economical terrorism on-site decontamination. The projects consists of (1) establishment of the decontamination evaluation methods and verification of the existing technologies and adaptation of bacterial organophosphorus hydrolase, (2) development of adsorptive elimination technologies using molecular recognition tools, and (4) development of deactivation technologies using photocatalysis.

Metal-organic frameworks for the removal of toxic industrial chemicals and chemical warfare agents.

Science.gov (United States)

Bobbitt, N Scott; Mendonca, Matthew L; Howarth, Ashlee J; Islamoglu, Timur; Hupp, Joseph T; Farha, Omar K; Snurr, Randall Q

2017-06-06

Owing to the vast diversity of linkers, nodes, and topologies, metal-organic frameworks can be tailored for specific tasks, such as chemical separations or catalysis. Accordingly, these materials have attracted significant interest for capture and/or detoxification of toxic industrial chemicals and chemical warfare agents. In this paper, we review recent experimental and computational work pertaining to the capture of several industrially-relevant toxic chemicals, including NH 3 , SO 2 , NO 2 , H 2 S, and some volatile organic compounds, with particular emphasis on the challenging issue of designing materials that selectively adsorb these chemicals in the presence of water. We also examine recent research on the capture and catalytic degradation of chemical warfare agents such as sarin and sulfur mustard using metal-organic frameworks.

Military chemical warfare agent human subjects testing: part 1--history of six-decades of military experiments with chemical warfare agents.

Science.gov (United States)

Brown, Mark

2009-10-01

Military chemical warfare agent testing from World War I to 1975 produced thousands of veterans with concerns of possible long-term health consequences. Clinical and research evaluation of potential long-term health effects has been difficult because the exposures occurred decades ago, the identity of troops exposed and exposure magnitudes are uncertain, and acute effects during experiments poorly documented. In contrast, a companion article describes the large amount of information available about the specific agents tested and their long-term health effects. This short history describes U.S. military chemical-agent experiments with human subjects and identifies tested agents. Finally, the demonstrated need to anticipate future health concerns from military personnel involved in such military testing suggests current and future military researchers should be required, by law and regulation, to fully record the identity of those exposed, relevant exposure magnitude, and complete medical information for all subjects. New study protocols and institutional review board approvals for research involving military personnel should reflect this need.

Blaptica dubia as sentinels for exposure to chemical warfare agents - a pilot study.

Science.gov (United States)

Worek, Franz; Seeger, Thomas; Neumaier, Katharina; Wille, Timo; Thiermann, Horst

2016-11-16

The increased interest of terrorist groups in toxic chemicals and chemical warfare agents presents a continuing threat to our societies. Early warning and detection is a key component for effective countermeasures against such deadly agents. Presently available and near term solutions have a number of major drawbacks, e.g. lack of automated, remote warning and detection of primarily low volatile chemical warfare agents. An alternative approach is the use of animals as sentinels for exposure to toxic chemicals. To overcome disadvantages of vertebrates the present pilot study was initiated to investigate the suitability of South American cockroaches (Blaptica dubia) as warning system for exposure to chemical warfare nerve and blister agents. Initial in vitro experiments with nerve agents showed an increasing inhibitory potency in the order tabun - cyclosarin - sarin - soman - VX of cockroach cholinesterase. Exposure of cockroaches to chemical warfare agents resulted in clearly visible and reproducible reactions, the onset being dependent on the agent and dose. With nerve agents the onset was related to the volatility of the agents. The blister agent lewisite induced signs largely comparable to those of nerve agents while sulfur mustard exposed animals exhibited a different sequence of events. In conclusion, this first pilot study indicates that Blaptica dubia could serve as a warning system to exposure of chemical warfare agents. A cockroach-based system will not detect or identify a particular chemical warfare agent but could trigger further actions, e.g. specific detection and increased protective status. By designing appropriate boxes with (IR) motion sensors and remote control (IR) camera automated off-site warning systems could be realized. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Reduced chemical warfare agent sorption in polyurethane-painted surfaces via plasma-enhanced chemical vapor deposition of perfluoroalkanes.

Science.gov (United States)

Gordon, Wesley O; Peterson, Gregory W; Durke, Erin M

2015-04-01

Perfluoralkalation via plasma chemical vapor deposition has been used to improve hydrophobicity of surfaces. We have investigated this technique to improve the resistance of commercial polyurethane coatings to chemicals, such as chemical warfare agents. The reported results indicate the surface treatment minimizes the spread of agent droplets and the sorption of agent into the coating. The improvement in resistance is likely due to reduction of the coating's surface free energy via fluorine incorporation, but may also have contributing effects from surface morphology changes. The data indicates that plasma-based surface modifications may have utility in improving chemical resistance of commercial coatings.

Recent canadian experience in chemical warfare agent destruction. An overview

Energy Technology Data Exchange (ETDEWEB)

McAndless, J.M.

1995-09-01

A Canadian chemical warfare agent destruction project (Swiftsure) was recently completed in which stockpiles of aged mustard, lewisite, nerve agents and contaminated scrap metal were incinerated or chemically neutralized in a safe, environmentally-responsible manner. The project scope, destruction technologies, environmental monitoring and public consultation programs are described.

Military chemical warfare agent human subjects testing: part 2--long-term health effects among participants of U.S. military chemical warfare agent testing.

Science.gov (United States)

Brown, Mark

2009-10-01

Military chemical warfare agent testing from World War I to 1975 produced thousands of veterans with concerns about how their participation affected their health. A companion article describes the history of these experiments, and how the lack of clinical data hampers evaluation of long-term health consequences. Conversely, much information is available about specific agents tested and their long-term health effects in other populations, which may be invaluable for helping clinicians respond effectively to the health care and other needs of affected veterans. The following review describes tested agents and their known long-term health consequences. Although hundreds of chemicals were tested, they fall into only about a half-dozen pharmaceutical classes, including common pharmaceuticals; anticholinesterase agents including military nerve agents and pesticides; anticholinergic glycolic acid esters such as atropine; acetylcholine reactivators such as 2-PAM; psychoactive compounds including cannabinoids, phencyclidine, and LSD; and irritants including tear gas and riot control agents.

Water-driven micromotors for rapid photocatalytic degradation of biological and chemical warfare agents.

Science.gov (United States)

Li, Jinxing; Singh, Virendra V; Sattayasamitsathit, Sirilak; Orozco, Jahir; Kaufmann, Kevin; Dong, Renfeng; Gao, Wei; Jurado-Sanchez, Beatriz; Fedorak, Yuri; Wang, Joseph

2014-11-25

Threats of chemical and biological warfare agents (CBWA) represent a serious global concern and require rapid and efficient neutralization methods. We present a highly effective micromotor strategy for photocatalytic degradation of CBWA based on light-activated TiO2/Au/Mg microspheres that propel autonomously in natural water and obviate the need for external fuel, decontaminating reagent, or mechanical agitation. The activated TiO2/Au/Mg micromotors generate highly reactive oxygen species responsible for the efficient destruction of the cell membranes of the anthrax simulant Bacillus globigii spore, as well as rapid and complete in situ mineralization of the highly persistent organophosphate nerve agents into nonharmful products. The water-driven propulsion of the TiO2/Au/Mg micromotors facilitates efficient fluid transport and dispersion of the photogenerated reactive oxidative species and their interaction with the CBWA. Coupling of the photocatalytic surface of the micromotors and their autonomous water-driven propulsion thus leads to a reagent-free operation which holds a considerable promise for diverse "green" defense and environmental applications.

Metal organic frameworks for the catalytic detoxification of chemical warfare nerve agents

Science.gov (United States)

Hupp, Joseph T.; Farha, Omar K.; Katz, Michael J.; Mondloch, Joseph E.

2017-04-18

A method of using a metal organic framework (MOF) comprising a metal ion and an at least bidendate organic ligand to catalytically detoxify chemical warfare nerve agents including exposing the metal-organic-framework (MOF) to the chemical warfare nerve agent and catalytically decomposing the nerve agent with the MOF.

Diagnosis of exposure to chemical warfare agents: An essential tool to counteract chemical terrorism

NARCIS (Netherlands)

Noort, D.; Schans, M.J. van der; Bikker, F.J.; Benschop, H.P.

2009-01-01

Methods to analyze chemical warfare agents (CW-agents) and their decomposition products in environmental samples were developed over the last decades. In contrast herewith, procedures for analysis in biological samples have only recently been developed. Retrospective detection of exposure to

Chemical Agents: Personal Cleaning and Disposal of Contaminated Clothing

Science.gov (United States)

... What CDC is Doing Blog: Public Health Matters Chemical Agents: Facts About Personal Cleaning and Disposal of ... on Facebook Tweet Share Compartir Some kinds of chemical accidents or attacks may cause you to come ...

Technological advancements for the detection of and protection against biological and chemical warfare agents.

Science.gov (United States)

Eubanks, Lisa M; Dickerson, Tobin J; Janda, Kim D

2007-03-01

There is a growing need for technological advancements to combat agents of chemical and biological warfare, particularly in the context of the deliberate use of a chemical and/or biological warfare agent by a terrorist organization. In this tutorial review, we describe methods that have been developed both for the specific detection of biological and chemical warfare agents in a field setting, as well as potential therapeutic approaches for treating exposure to these toxic species. In particular, nerve agents are described as a typical chemical warfare agent, and the two potent biothreat agents, anthrax and botulinum neurotoxin, are used as illustrative examples of potent weapons for which countermeasures are urgently needed.

Evaluation of Chlamydia pneumoniae and Mycoplasma pneumoniae as etiologic agents of persistent cough in adolescents and adults.

Science.gov (United States)

Wadowsky, Robert M; Castilla, Elias A; Laus, Stella; Kozy, Anita; Atchison, Robert W; Kingsley, Lawrence A; Ward, Joel I; Greenberg, David P

2002-02-01

Chlamydia pneumoniae and Mycoplasma pneumoniae were evaluated as agents of persistent cough in adolescents and adults (n = 491). Tests of 473 respiratory specimens by culture or PCR or both identified four episodes (0.8%) of M. pneumoniae-associated illness and no episodes of C. pneumoniae illness, suggesting that these bacteria do not frequently cause persistent cough.

Insect-gene-activity detection system for chemical and biological warfare agents and toxic industrial chemicals

Science.gov (United States)

Mackie, Ryan S.; Schilling, Amanda S.; Lopez, Arturo M.; Rayms-Keller, Alfredo

2002-02-01

Detection of multiple chemical and biological weapons (CBW) agents and/or complex mixtures of toxic industrial chemicals (TIC) is imperative for both the commercial and military sectors. In a military scenario, a multi-CBW attack would create confusion, thereby delaying decontamination and therapeutic efforts. In the commercial sector, polluted sites invariably contain a mixture of TIC. Novel detection systems capable of detecting CBW and TIC are sorely needed. While it may be impossible to build a detector capable of discriminating all the possible combinations of CBW, a detection system capable of statistically predicting the most likely composition of a given mixture is within the reach of current emerging technologies. Aquatic insect-gene activity may prove to be a sensitive, discriminating, and elegant paradigm for the detection of CBW and TIC. We propose to systematically establish the expression patterns of selected protein markers in insects exposed to specific mixtures of chemical and biological warfare agents to generate a library of biosignatures of exposure. The predicting capabilities of an operational library of biosignatures of exposures will allow the detection of emerging novel or genetically engineered agents, as well as complex mixtures of chemical and biological weapons agents. CBW and TIC are discussed in the context of war, terrorism, and pollution.

Mass spectrometry in identification of ecotoxicants including chemical and biological warfare agents

International Nuclear Information System (INIS)

Lebedev, Albert T.

2005-01-01

Mass spectrometry is a unique tool to detect and identify trace levels of organic and bioorganic compounds as well as microorganisms in the environment. The range of potential chemical warfare (CW) and biological warfare (BW) agents is very broad. An important advantage of mass spectrometry over other techniques involves potential for full spectrum detection of chemical and biological agents including mid-spectrum materials (i.e. bioactive peptides, toxins, etc.) for which biological approaches are inadequate. Being very fast (seconds and minutes), extremely sensitive (zeptomoles 10 -21 ), and informative (detailed qualitative and quantitative composition of mixtures containing hundreds of chemicals), mass spectrometry is a principal analytical tool at the sites of destruction of CW. Due to its unique features, mass spectrometry is applied not only for the detection of CW agents, but for the analysis of products of metabolism and degradation of these agents in organisms or environment as well. The present paper deals with some examples of successful application of mass spectrometry for the analyses of ecotoxicants, chemical warfare agents, explosives, and microorganisms including biology warfare agents

Limitations and challenges in treatment of acute chemical warfare agent poisoning.

Science.gov (United States)

Thiermann, Horst; Worek, Franz; Kehe, Kai

2013-12-05

Recent news from Syria on a possible use of chemical warfare agents made the headlines. Furthermore, the motivation of terrorists to cause maximal harm shifts these agents into the public focus. For incidents with mass casualties appropriate medical countermeasures must be available. At present, the most important threats arise from nerve agents and sulfur mustard. At first, self-protection and protection of medical units from contamination is of utmost importance. Volatile nerve agent exposure, e.g. sarin, results in fast development of cholinergic crisis. Immediate clinical diagnosis can be confirmed on-site by assessment of acetylcholinesterase activity. Treatment with autoinjectors that are filled with 2mg atropine and an oxime (at present obidoxime, pralidoxime, TMB-4 or HI-6) are not effective against all nerve agents. A more aggressive atropinisation has to be considered and more effective oximes (if possible with a broad spectrum or a combination of different oximes) as well as alternative strategies to cope with high acetylcholine levels at synaptic sites should be developed. A further gap exists for the treatment of patients with sustained cholinergic crisis that has to be expected after exposure to persistent nerve agents, e.g. VX. The requirement for long-lasting artificial ventilation can be reduced with an oxime therapy that is optimized by using the cholinesterase status for guidance or by measures (e.g. scavengers) that are able to reduce the poison load substantially in the patients. For sulfur mustard poisoning no specific antidote is available until now. Symptomatic measures as used for treatment of burns are recommended together with surgical or laser debridement. Thus, huge amounts of resources are expected to be consumed as wound healing is impaired. Possible depots of sulfur mustard in tissues may aggravate the situation. More basic knowledge is necessary to improve substantially therapeutic options. The use of stem cells may provide a new

Mustard Group Chemical War Agents from Preventive Medicine Perspective

Directory of Open Access Journals (Sweden)

Muharrem Ucar

2007-06-01

Full Text Available Although many preventive efforts and treaties, chemical warfare agents have still been a severe assault form against both military and civilian individuals. The most important chemical warfare agents sulphur mustard and others are easy to handle and cheap those the important reasons to accept sulphur mustard as a chemical warfare agent. Many individuals attacked by sulphur mustard have severe health problems such as respiratory system diseases. After ten years of sulphur mustard exposure, several health problems such as respiratory tract problems (%42.5, eye problems (%40 and other systemic diseases have been observed to insist on induviduals when examined. Exposure of even single sulphur mustard exposure has been seen to result high level of disability and early deaths. In spite of the fact that there is no available antidote and/or remedy against sulphur mustard exposure, our country has an incremental chemical assault threat for both military personels and civilians because of its jeopolitics position. Experimental studies regarding sulphur mustard toxicity will be helpful for novel preventive strategies and antidot devolepment. [TAF Prev Med Bull 2007; 6(3.000: 209-214

Antidotes and treatments for chemical warfare/terrorism agents: an evidence-based review.

Science.gov (United States)

Rodgers, G C; Condurache, C T

2010-09-01

This article reviews the evidence supporting the efficacy of antidotes used or recommended for the potential chemical warfare agents of most concern. Chemical warfare agents considered include cyanide, vesicants, pulmonary irritants such as chlorine and phosgene, and nerve agents. The strength of evidence for most antidotes is weak, highlighting the need for additional research in this area.

Deactivating Chemical Agents Using Enzyme-Coated Nanofibers Formed by Electrospinning

Science.gov (United States)

2016-01-01

7.3mM/mg). Key words Coaxial electrospinning, DFPase, Enzyme, chemical warfare , nanofiber, decontamination . Introduction Chemical warfare ...Krile, R.; Nishioka, M.; Taylor, M.; Riggs, K.; Stone, H. Decontamination of Toxic Industrial Chemicals and Chemical Warfare Agents On Building...298 (Rev. 8-98) Prescribed by ANSI Std. Z39.18 MATS COATINGS ELECTROSPINNING CHEMICAL WARFARE

Double agents and secret agents: the emerging fields of exogenous chemical exchange saturation transfer and T2-exchange magnetic resonance imaging contrast agents for molecular imaging.

Science.gov (United States)

Daryaei, Iman; Pagel, Mark D

2015-01-01

Two relatively new types of exogenous magnetic resonance imaging contrast agents may provide greater impact for molecular imaging by providing greater specificity for detecting molecular imaging biomarkers. Exogenous chemical exchange saturation transfer (CEST) agents rely on the selective saturation of the magnetization of a proton on an agent, followed by chemical exchange of a proton from the agent to water. The selective detection of a biomarker-responsive CEST signal and an unresponsive CEST signal, followed by the ratiometric comparison of these signals, can improve biomarker specificity. We refer to this improvement as a "double-agent" approach to molecular imaging. Exogenous T 2 -exchange agents also rely on chemical exchange of protons between the agent and water, especially with an intermediate rate that lies between the slow exchange rates of CEST agents and the fast exchange rates of traditional T 1 and T 2 agents. Because of this intermediate exchange rate, these agents have been relatively unknown and have acted as "secret agents" in the contrast agent research field. This review exposes these secret agents and describes the merits of double agents through examples of exogenous agents that detect enzyme activity, nucleic acids and gene expression, metabolites, ions, redox state, temperature, and pH. Future directions are also provided for improving both types of contrast agents for improved molecular imaging and clinical translation. Therefore, this review provides an overview of two new types of exogenous contrast agents that are becoming useful tools within the armamentarium of molecular imaging.

Biomonitoring of exposure to chemical warfare agents: A review

NARCIS (Netherlands)

Noort, D.; Benschop, H.P.; Black, R.M.

2002-01-01

In this report an overview of the methods currently available for detection of exposure to a number of chemical warfare agents (CWA), i.e., sulfur mustard, lewisite and nerve agents, is presented. Such methods can be applied for various purposes, e.g., diagnosis and dosimetry of exposure of

Oxidative decontamination of chemical and biological warfare agents using L-Gel.

Science.gov (United States)

Raber, Ellen; McGuire, Raymond

2002-08-05

A decontamination method has been developed using a single reagent that is effective both against chemical warfare (CW) and biological warfare (BW) agents. The new reagent, "L-Gel", consists of an aqueous solution of a mild commercial oxidizer, Oxone, together with a commercial fumed silica gelling agent, Cab-O-Sil EH-5. L-Gel is non-toxic, environmentally friendly, relatively non-corrosive, maximizes contact time because of its thixotropic nature, clings to walls and ceilings, and does not harm carpets or painted surfaces. The new reagent also addresses the most demanding requirements for decontamination in the civilian sector, including availability, low maintenance, ease of application and deployment by a variety of dispersal mechanisms, minimal training and acceptable expense. Experiments to test the effectiveness of L-Gel were conducted at Lawrence Livermore National Laboratory and independently at four other locations. L-Gel was tested against all classes of chemical warfare agents and against various biological warfare agent surrogates, including spore-forming bacteria and non-virulent strains of real biological agents. Testing showed that L-Gel is as effective against chemical agents and biological materials, including spores, as the best military decontaminants.

IMS software developments for the detection of chemical warfare agent

Science.gov (United States)

Klepel, ST.; Graefenhain, U.; Lippe, R.; Stach, J.; Starrock, V.

1995-01-01

Interference compounds like gasoline, diesel, burning wood or fuel, etc. are presented in common battlefield situations. These compounds can cause detectors to respond as a false positive or interfere with the detector's ability to respond to target compounds such as chemical warfare agents. To ensure proper response of the ion mobility spectrometer to chemical warfare agents, two special software packages were developed and incorporated into the Bruker RAID-1. The programs suppress interferring signals caused by car exhaust or smoke gases resulting from burning materials and correct the influence of variable sample gas humidity which is important for detection and quantification of blister agents like mustard gas or lewisite.

Evaluation of the persistence in the induction of Sister Chromatid Exchanges (SCE) by alkylating agents

International Nuclear Information System (INIS)

Rodriguez R, R.; Huerta V, C.; MOrales R, P.R.

2006-01-01

The persistence in the induction of sister chromatid exchanges (SCE) by the alkylating agents methyl and ethyl-methanesulfonates (MMS and EMS) was evaluated. For it, to groups of mice its were administered a dose of these agents and later its were analyzed the induced SCE's in two periods: early and late. Both agents caused high increments of SCE in the early period and small in the late one; however, the caused lately by EMS was significantly bigger. This late induction of SCE by EMS possibly is associated with an epigenetic change or with the presence of etiladucts in the phosphodiester bonds of the DNA. (Author)

Applicability of federal and state hazardous waste regulatory programs to waste chemical weapons and chemical warfare agents.; TOPICAL

International Nuclear Information System (INIS)

Haffenden, R.; Kimmell, T.

2002-01-01

This report reviews federal and state hazardous waste regulatory programs that govern the management of chemical weapons or chemical warfare agents. It addresses state programs in the eight states with chemical weapon storage facilities managed by the U.S. Army: Alabama, Arkansas, Colorado, Indiana, Kentucky, Maryland, Oregon, and Utah. It also includes discussions on 32 additional states or jurisdictions with known or suspected chemical weapons or chemical warfare agent presence (e.g., disposal sites containing chemical agent identification sets): Alaska, Arizona, California, Florida, Georgia, Hawaii, Idaho, Illinois, Iowa, Kansas, Louisiana, Massachusetts, Michigan, Mississippi, Missouri, Nebraska, Nevada, New Jersey, New Mexico, New York, North Carolina, Ohio, Pennsylvania, South Carolina, South Dakota, Tennessee, Texas, the U.S. Virgin Islands, Virginia, Washington, Washington, D.C., and Wyoming. Resource Conservation and Recovery Act (RCRA) hazardous waste programs are reviewed to determine whether chemical weapons or chemical warfare agents are listed hazardous wastes or otherwise defined or identified as hazardous wastes. Because the U.S. Environmental Protection Agency (EPA) military munitions rule specifically addresses the management of chemical munitions, this report also indicates whether a state has adopted the rule and whether the resulting state regulations have been authorized by EPA. Many states have adopted parts or all of the EPA munitions rule but have not yet received authorization from EPA to implement the rule. In these cases, the states may enforce the adopted munitions rule provisions under state law, but these provisions are not federally enforceable

Bubble Jet agent release cartridge for chemical single cell stimulation.

Science.gov (United States)

Wangler, N; Welsche, M; Blazek, M; Blessing, M; Vervliet-Scheebaum, M; Reski, R; Müller, C; Reinecke, H; Steigert, J; Roth, G; Zengerle, R; Paust, N

2013-02-01

We present a new method for the distinct specific chemical stimulation of single cells and small cell clusters within their natural environment. By single-drop release of chemical agents with droplets in size of typical cell diameters (d agent release cartridge with integrated fluidic structures and integrated agent reservoirs are shown, tested, and compared in this publication. The single channel setup features a fluidic structure fabricated by anisotropic etching of silicon. To allow for simultaneous release of different agents even though maintaining the same device size, the second type comprises a double channel fluidic structure, fabricated by photolithographic patterning of TMMF. Dispensed droplet volumes are V = 15 pl and V = 10 pl for the silicon and the TMMF based setups, respectively. Utilizing the agent release cartridges, the application in biological assays was demonstrated by hormone-stimulated premature bud formation in Physcomitrella patens and the individual staining of one single L 929 cell within a confluent grown cell culture.

Effect of Biological and Chemical Ripening Agents on the Nutritional ...

African Journals Online (AJOL)

Effect of Biological and Chemical Ripening Agents on the Nutritional and Metal Composition of Banana ( Musa spp ) ... Journal Home > Vol 18, No 2 (2014) > ... curcas leaf were used and compared with a control with no ripening agent.

Biodegradation of Organophosphate Chemical Warfare Agents by Activated Sludge

Science.gov (United States)

2012-03-01

bronchoconstriction Bladder (M) Urinary frequency, incontinence Cardiovascular system (M) Bradycardia, hypotension Cardiovascular system (N...conventional weapons: their cost and stability, simplicity of production, pound for pound potency and fear factor (Hill et al., 2008a). Compared to...Chemical agents, especially nerve agents, have a dramatic fear factor due to the symptoms they cause. Witnessing civilians violently convulsing

Destruction and waste treatment methods used in a chemical agent disposal project. Memorandum report

Energy Technology Data Exchange (ETDEWEB)

McAndless, J.; Fedor, V.; Kinderwater, T.

1992-10-01

This report describes the equipment and methods used to thermally decontaminate scrap metal and destroy stockpiles of nerve agents, mustard and lewisite chemical warfare agents. Mustard was destroyed by direct incineration whereas the nerve agents and lewisite were chemically neutralized. The arsenic waste from the lewisite neutralization process was chemically-fixated in concrete for final disposal by landfilling. The scrap metal was incinerated and rendered suitable for recycling into metal feedstock.

Persistence and Effective Half-Life of Chemical Warfare Agent VX on Grass Foliage

Science.gov (United States)

2017-08-01

the plant leaves, including leaf epicuticular waxes and cuticle (Sanyal et al., 2006; Simini et al., 2016). The extent of persistence, penetration...diameter pots had been lined with two pieces of absorbent paper , then filled with 170 g (77.1 g dry mass) of the potting mix. After 7d post...replicate VX-contaminated leaves and respective negative (no VX) control leaves were removed from plants at specified times for analytical determination of

Identifying new persistent and bioaccumulative organics among chemicals in commerce.

Science.gov (United States)

Howard, Philip H; Muir, Derek C G

2010-04-01

The goal of this study was to identify commercial chemicals that might be persistent and bioaccumulative (P&B) and that were not being considered in current Great Lakes, North American, and Arctic contaminant measurement programs. We combined the Canadian Domestic Substance List (DSL), a list of 3059 substances of "unknown or variable composition complex reaction products and biological materials" (UVCBs), and the U.S. Environmental Protection Agency (U.S. EPA) Toxic Substances Control Act (TSCA) Inventory Update Rule (IUR) database for years 1986, 1990, 1994, 1998, 2002, and 2006 yielding a database of 22263 commercial chemicals. From that list, 610 chemicals were identified by estimates from U.S EPA EPISuite software and using expert judgment. This study has yielded some interesting and probable P&B chemicals that should be considered for further study. Recent studies, following up our initial reports and presentations on this work, have confirmed the presence of many of these chemicals in the environment.

Modeling the transport of chemical warfare agents and simulants in polymeric substrates for reactive decontamination

Science.gov (United States)

Pearl, Thomas; Mantooth, Brent; Varady, Mark; Willis, Matthew

2014-03-01

Chemical warfare agent simulants are often used for environmental testing in place of highly toxic agents. This work sets the foundation for modeling decontamination of absorbing polymeric materials with the focus on determining relationships between agents and simulants. The correlations of agents to simulants must consider the three way interactions in the chemical-material-decontaminant system where transport and reaction occur in polymer materials. To this end, diffusion modeling of the subsurface transport of simulants and live chemical warfare agents was conducted for various polymer systems (e.g., paint coatings) with and without reaction pathways with applied decontamination. The models utilized 1D and 2D finite difference diffusion and reaction models to simulate absorption and reaction in the polymers, and subsequent flux of the chemicals out of the polymers. Experimental data including vapor flux measurements and dynamic contact angle measurements were used to determine model input parameters. Through modeling, an understanding of the relationship of simulant to live chemical warfare agent was established, focusing on vapor emission of agents and simulants from materials.

Transport and Reactivity of Decontaminants to Provide Hazard Mitigation of Chemical Warfare Agents from Materials

Science.gov (United States)

2016-06-01

2013 4. TITLE AND SUBTITLE Transport and Reactivity of Decontaminants to Provide Hazard Mitigation of Chemical Warfare Agents from Materials 5a...directions for future decontamination formulation approaches. 15. SUBJECT TERMS GD HD Decontamination Hazard mitigation VX Chemical warfare agent... DECONTAMINANTS TO PROVIDE HAZARD MITIGATION OF CHEMICAL WARFARE AGENTS FROM MATERIALS 1. INTRODUCTION Decontamination of materials is the

Tissue-based standoff biosensors for detecting chemical warfare agents

Science.gov (United States)

Greenbaum, Elias; Sanders, Charlene A.

2003-11-18

A tissue-based, deployable, standoff air quality sensor for detecting the presence of at least one chemical or biological warfare agent, includes: a cell containing entrapped photosynthetic tissue, the cell adapted for analyzing photosynthetic activity of the entrapped photosynthetic tissue; means for introducing an air sample into the cell and contacting the air sample with the entrapped photosynthetic tissue; a fluorometer in operable relationship with the cell for measuring photosynthetic activity of the entrapped photosynthetic tissue; and transmitting means for transmitting analytical data generated by the fluorometer relating to the presence of at least one chemical or biological warfare agent in the air sample, the sensor adapted for deployment into a selected area.

Atmospheric emissions and long-range transport of persistent organic chemicals

Directory of Open Access Journals (Sweden)

Scheringer M.

2010-12-01

Full Text Available Persistent organic chemicals include several groups of halogenated compounds, such as polychlorinated biphenyls (PCBs, polybrominated diphenylethers (PBDEs, and polyfluorinated carboxylic acids (PFCAs. These chemicals remain for long times (years to decades in the environment and cycle between different media (air, water, sediment, soil, vegetation, etc.. The environmental distribution of this type of chemicals can conveniently be analyzed by multimedia models. Multimedia models consist of a set of coupled mass balance equations for the environmental media considered; they can be set up at various scales from local to global. Two applications of multimedia models to airborne chemicals are discussed in detail: the day-night cycle of PCBs measured in air near the surface, and the atmospheric long-range transport of volatile precursors of PFCAs, formation of PFCAs by oxidation of these precursors, and subsequent deposition of PFCAs to the surface in remote regions such as the Arctic.

The Scarlet Letter of Alkylation: A Mini Review of Selective Alkylating Agents

OpenAIRE

Oronsky, Bryan T; Reid, Tony; Knox, Susan J; Scicinski, Jan J

2012-01-01

If there were a stigma scale for chemotherapy, alkylating agents would be ranked at the top of the list. The chemical term alkylation is associated with nonselective toxicity, an association that dates back to the use of nitrogen mustards during World War I as chemical warfare agents. That this stigma persists and extends to compounds that, through selectivity, attempt to “tame” the indiscriminate destructive potential of alkylation is the subject of this review. Selective alkylation, as it i...

Tissue-based water quality biosensors for detecting chemical warfare agents

Science.gov (United States)

Greenbaum, Elias [Oak Ridge, TN; Sanders, Charlene A [Knoxville, TN

2003-05-27

A water quality sensor for detecting the presence of at least one chemical or biological warfare agent includes: a cell; apparatus for introducing water into the cell and discharging water from the cell adapted for analyzing photosynthetic activity of naturally occurring, free-living, indigenous photosynthetic organisms in water; a fluorometer for measuring photosynthetic activity of naturally occurring, free-living, indigenous photosynthetic organisms drawn into the cell; and an electronics package that analyzes raw data from the fluorometer and emits a signal indicating the presence of at least one chemical or biological warfare agent in the water.

Laboratory analysis of chemical warfare agents, adducts, and metabolites in biomedial samples

NARCIS (Netherlands)

Schans, M.J. van der

2015-01-01

Chemical warfare agents (CWAs) are the most toxic compounds ever produced. To develop medical countermeasures against the effects of these agents, analytical procedures to analyze these agents in biological matrices are essential for a better understanding of the toxicological process. The need for

Antioxidants as potential medical countermeasures for chemical warfare agents and toxic industrial chemicals.

Science.gov (United States)

McElroy, Cameron S; Day, Brian J

2016-01-15

The continuing horrors of military conflicts and terrorism often involve the use of chemical warfare agents (CWAs) and toxic industrial chemicals (TICs). Many CWA and TIC exposures are difficult to treat due to the danger they pose to first responders and their rapid onset that can produce death shortly after exposure. While the specific mechanism(s) of toxicity of these agents are diverse, many are associated either directly or indirectly with increased oxidative stress in affected tissues. This has led to the exploration of various antioxidants as potential medical countermeasures for CWA/TIC exposures. Studies have been performed across a wide array of agents, model organisms, exposure systems, and antioxidants, looking at an almost equally diverse set of endpoints. Attempts at treating CWAs/TICs with antioxidants have met with mixed results, ranging from no effect to nearly complete protection. The aim of this commentary is to summarize the literature in each category for evidence of oxidative stress and antioxidant efficacy against CWAs and TICs. While there is great disparity in the data concerning methods, models, and remedies, the outlook on antioxidants as medical countermeasures for CWA/TIC management appears promising. Copyright © 2015 Elsevier Inc. All rights reserved.

Researchers study decontamination of chemical, biological warfare agents

OpenAIRE

Trulove, Susan

2007-01-01

The U.S. Army Research Office has awarded Virginia Tech a $680,000 grant over two years to build an instrument that can be used to study the chemistry of gases that will decompose both chemical and biological warfare agents on surfaces.

Extrudates of starch-xanthan gum mixtures as affected by chemical agents and irradiation

International Nuclear Information System (INIS)

Hanna, M.A.; Chinnaswamy, R.; Gray, D.R.; Miladinov, V.D.

1997-01-01

Mixtures of starch, xanthan gum and either polyvinyl alcohol, epichlorohydrin, valeric acid or adipoyl chloride were extruded. Properties of extrudates including apparent viscosity, water solubility, water absorption indices and extrudate expansion were measured for different proportions of xanthan gum, 70% amylose starch (with or without irradiation) and chemical agents. Extrusion with chemical agents and irradiation changed physical properties of both starch and xanthan gum. Expansions of extrudates were higher than that of starch. Viscosity of extrudates increased with xanthan gum concentration. The addition of 1% (w/w) polyvinyl alcohol had the greatest effect of the chemical agents. Irradiation increased the apparent viscosity of starch-xanthan gum mixtures

Fluorescent discrimination between traces of chemical warfare agents and their mimics.

Science.gov (United States)

Díaz de Greñu, Borja; Moreno, Daniel; Torroba, Tomás; Berg, Alexander; Gunnars, Johan; Nilsson, Tobias; Nyman, Rasmus; Persson, Milton; Pettersson, Johannes; Eklind, Ida; Wästerby, Pär

2014-03-19

An array of fluorogenic probes is able to discriminate between nerve agents, sarin, soman, tabun, VX and their mimics, in water or organic solvent, by qualitative fluorescence patterns and quantitative multivariate analysis, thus making the system suitable for the in-the-field detection of traces of chemical warfare agents as well as to differentiate between the real nerve agents and other related compounds.

Understanding evaporation characteristics of a drop of distilled sulfur mustard (HD) chemical agent from stainless steel and aluminum substrates

Energy Technology Data Exchange (ETDEWEB)

Jung, H., E-mail: junghs@add.re.kr; Lee, H.W.

2014-05-01

Highlights: • Evaporation rates of HD are obtained from stainless steel and aluminum substrates. • The rates increase with temperature and are linearly proportional to drop size. • HD evaporation from stainless steel follows only constant contact area mechanism. • HD evaporation from aluminum proceeds by a combined mechanism. - Abstract: We report herein the evaporation rates and mechanism of a drop of distilled sulfur mustard (HD) agent from stainless steel and aluminum substrates. For systematic analysis, we used a laboratory-sized wind tunnel, thermal desorption (TD) connected to gas chromatograph/mass spectrometry (GC/MS) and drop shape analysis (DSA). We found that the evaporation rates of HD from stainless steel and aluminum increased with temperature. The rates were also linearly proportional to drop size. The time-dependent contact angle measurement showed that the evaporation of the drop of HD proceeded only by constant contact area mechanism from stainless steel surface. On the other hand, the evaporation of HD from aluminum proceeded by a combined mechanism of constant contact area mode and constant contact angle mode. Our experimental data sets and analysis could be used to predict vapor and contact hazard persistence of chemical warfare agents (CWAs) in the air and on exterior surfaces with chemical releases, which assists the military decision influencing personnel safety and decontamination of the site upon a chemical attack event.

Understanding evaporation characteristics of a drop of distilled sulfur mustard (HD) chemical agent from stainless steel and aluminum substrates

International Nuclear Information System (INIS)

Jung, H.; Lee, H.W.

2014-01-01

Highlights: • Evaporation rates of HD are obtained from stainless steel and aluminum substrates. • The rates increase with temperature and are linearly proportional to drop size. • HD evaporation from stainless steel follows only constant contact area mechanism. • HD evaporation from aluminum proceeds by a combined mechanism. - Abstract: We report herein the evaporation rates and mechanism of a drop of distilled sulfur mustard (HD) agent from stainless steel and aluminum substrates. For systematic analysis, we used a laboratory-sized wind tunnel, thermal desorption (TD) connected to gas chromatograph/mass spectrometry (GC/MS) and drop shape analysis (DSA). We found that the evaporation rates of HD from stainless steel and aluminum increased with temperature. The rates were also linearly proportional to drop size. The time-dependent contact angle measurement showed that the evaporation of the drop of HD proceeded only by constant contact area mechanism from stainless steel surface. On the other hand, the evaporation of HD from aluminum proceeded by a combined mechanism of constant contact area mode and constant contact angle mode. Our experimental data sets and analysis could be used to predict vapor and contact hazard persistence of chemical warfare agents (CWAs) in the air and on exterior surfaces with chemical releases, which assists the military decision influencing personnel safety and decontamination of the site upon a chemical attack event

Study on the identification method of chemical warfare agents with spectroscopy of neutron induced γ rays

International Nuclear Information System (INIS)

Liu Boxue; Li Yun; Li Xiangbao

1996-01-01

The paper briefly describes some non-destructive verification technologies of chemical warfare agents in-site, and some application of neutron induced gamma ray analysis, such as multi-elements analysis of coal, hidden explosive detection and identification of chemical agents. It also describes some problems in developing the portable isotopic neutron spectroscopy for non-destructive evaluation of chemical warfare agents

Improving the risk assessment of lipophilic persistent environmental chemicals in breast milk.

Science.gov (United States)

Lehmann, Geniece M; Verner, Marc-André; Luukinen, Bryan; Henning, Cara; Assimon, Sue Anne; LaKind, Judy S; McLanahan, Eva D; Phillips, Linda J; Davis, Matthew H; Powers, Christina M; Hines, Erin P; Haddad, Sami; Longnecker, Matthew P; Poulsen, Michael T; Farrer, David G; Marchitti, Satori A; Tan, Yu-Mei; Swartout, Jeffrey C; Sagiv, Sharon K; Welsh, Clement; Campbell, Jerry L; Foster, Warren G; Yang, Raymond S H; Fenton, Suzanne E; Tornero-Velez, Rogelio; Francis, Bettina M; Barnett, John B; El-Masri, Hisham A; Simmons, Jane Ellen

2014-08-01

Lipophilic persistent environmental chemicals (LPECs) have the potential to accumulate within a woman's body lipids over the course of many years prior to pregnancy, to partition into human milk, and to transfer to infants upon breastfeeding. As a result of this accumulation and partitioning, a breastfeeding infant's intake of these LPECs may be much greater than his/her mother's average daily exposure. Because the developmental period sets the stage for lifelong health, it is important to be able to accurately assess chemical exposures in early life. In many cases, current human health risk assessment methods do not account for differences between maternal and infant exposures to LPECs or for lifestage-specific effects of exposure to these chemicals. Because of their persistence and accumulation in body lipids and partitioning into breast milk, LPECs present unique challenges for each component of the human health risk assessment process, including hazard identification, dose-response assessment, and exposure assessment. Specific biological modeling approaches are available to support both dose-response and exposure assessment for lactational exposures to LPECs. Yet, lack of data limits the application of these approaches. The goal of this review is to outline the available approaches and to identify key issues that, if addressed, could improve efforts to apply these approaches to risk assessment of lactational exposure to these chemicals.

Simulated experiment for elimination of chemical and biological warfare agents by making use of microwave plasma torch

International Nuclear Information System (INIS)

Hong, Yong C.; Kim, Jeong H.; Uhm, Han S.

2004-01-01

The threat of chemical and biological warfare agents in a domestic terrorist attack and in military conflict is increasing worldwide. Elimination and decontamination of chemical and biological warfare (CBW) agents are immediately required after such an attack. Simulated experiment for elimination of CBW agents by making use of atmospheric-pressure microwave plasma torches is carried out. Elimination of biological warfare agents indicated by the vitrification or burnout of sewage sludge powders and decomposition of toluene gas as a chemical agent stimulant are presented. A detailed characterization for the elimination of the simulant chemicals using Fourier transform infrared and gas chromatography is also presented

Simulated experiment for elimination of chemical and biological warfare agents by making use of microwave plasma torch

Science.gov (United States)

Hong, Yong C.; Kim, Jeong H.; Uhm, Han S.

2004-02-01

The threat of chemical and biological warfare agents in a domestic terrorist attack and in military conflict is increasing worldwide. Elimination and decontamination of chemical and biological warfare (CBW) agents are immediately required after such an attack. Simulated experiment for elimination of CBW agents by making use of atmospheric-pressure microwave plasma torches is carried out. Elimination of biological warfare agents indicated by the vitrification or burnout of sewage sludge powders and decomposition of toluene gas as a chemical agent stimulant are presented. A detailed characterization for the elimination of the simulant chemicals using Fourier transform infrared and gas chromatography is also presented.

Using cheminformatics to find simulants for chemical warfare agents

Energy Technology Data Exchange (ETDEWEB)

Lavoie, J.; Srinivasan, Sree [Molecular Sciences and Engineering Team, U.S. Army Natick Soldier Research, Development and Engineering Center, 15 Kansas Street, Natick, MA 01760 (United States); Nagarajan, R., E-mail: Ramanathan.Nagarajan@us.army.mil [Molecular Sciences and Engineering Team, U.S. Army Natick Soldier Research, Development and Engineering Center, 15 Kansas Street, Natick, MA 01760 (United States)

2011-10-30

Highlights: {yields} Summary of chemical warfare agent (CWA) simulants in current use. {yields} Application of method of molecular similarity to CWA and simulants. {yields} Quantitative metric for CWA-simulant similarity. {yields} Rank ordering of simulants in current use. {yields} Potential of method to identify simulants for emerging agents. - Abstract: Direct experimentation with chemical warfare agents (CWA) to study important problems such as their permeation across protective barrier materials, decontamination of equipment and facilities, or the environmental transport and fate of CWAs is not feasible because of the obvious toxicity of the CWAs and associated restrictions on their laboratory use. The common practice is to use 'simulants,' namely, analogous chemicals that closely resemble the CWAs but are less toxic, with the expectation that the results attained for simulants can be correlated to how the CWAs would perform. Simulants have been traditionally chosen by experts, by means of intuition, using similarity in one or more physical properties (such as vapor pressure or aqueous solubility) or in the molecular structural features (such as functional groups) between the stimulant and the CWA. This work is designed to automate the simulant identification process backed by quantitative metrics, by means of chemical similarity search software routinely used in pharmaceutical drug discovery. The question addressed here is: By the metrics of such software, how similar are traditional simulants to CWAs? That is, what is the numerical 'distance' between each CWA and its customary simulants in the quantitative space of molecular descriptors? The answers show promise for finding close but less toxic simulants for the ever-increasing numbers of CWAs objectively and fast.

Using cheminformatics to find simulants for chemical warfare agents

International Nuclear Information System (INIS)

Lavoie, J.; Srinivasan, Sree; Nagarajan, R.

2011-01-01

Highlights: → Summary of chemical warfare agent (CWA) simulants in current use. → Application of method of molecular similarity to CWA and simulants. → Quantitative metric for CWA-simulant similarity. → Rank ordering of simulants in current use. → Potential of method to identify simulants for emerging agents. - Abstract: Direct experimentation with chemical warfare agents (CWA) to study important problems such as their permeation across protective barrier materials, decontamination of equipment and facilities, or the environmental transport and fate of CWAs is not feasible because of the obvious toxicity of the CWAs and associated restrictions on their laboratory use. The common practice is to use 'simulants,' namely, analogous chemicals that closely resemble the CWAs but are less toxic, with the expectation that the results attained for simulants can be correlated to how the CWAs would perform. Simulants have been traditionally chosen by experts, by means of intuition, using similarity in one or more physical properties (such as vapor pressure or aqueous solubility) or in the molecular structural features (such as functional groups) between the stimulant and the CWA. This work is designed to automate the simulant identification process backed by quantitative metrics, by means of chemical similarity search software routinely used in pharmaceutical drug discovery. The question addressed here is: By the metrics of such software, how similar are traditional simulants to CWAs? That is, what is the numerical 'distance' between each CWA and its customary simulants in the quantitative space of molecular descriptors? The answers show promise for finding close but less toxic simulants for the ever-increasing numbers of CWAs objectively and fast.

Sea-dumped chemical weapons: environmental risk, occupational hazard.

Science.gov (United States)

Greenberg, M I; Sexton, K J; Vearrier, D

2016-01-01

Chemical weapons dumped into the ocean for disposal in the twentieth century pose a continuing environmental and human health risk. In this review we discuss locations, quantity, and types of sea-dumped chemical weapons, related environmental concerns, and human encounters with sea-dumped chemical weapons. We utilized the Ovid (http://ovidsp.tx.ovid.com) and PubMed (http://www.pubmed.org) search engines to perform MEDLINE searches for the terms 'sea-dumped chemical weapons', 'chemical warfare agents', and 'chemical munitions'. The searches returned 5863 articles. Irrelevant and non-English articles were excluded. A review of the references for these articles yielded additional relevant sources, with a total of 64 peer-reviewed articles cited in this paper. History and geography of chemical weapons dumping at sea: Hundreds of thousands of tons of chemical munitions were disposed off at sea following World War II. European, Russian, Japanese, and United States coasts are the areas most affected worldwide. Several areas in the Baltic and North Seas suffered concentrated large levels of dumping, and these appear to be the world's most studied chemical warfare agent marine dumping areas. Chemical warfare agents: Sulfur mustard, Lewisite, and the nerve agents appear to be the chemical warfare agents most frequently disposed off at sea. Multiple other type of agents including organoarsenicals, blood agents, choking agents, and lacrimators were dumped at sea, although in lesser volumes. Environmental concerns: Numerous geohydrologic variables contribute to the rate of release of chemical agents from their original casings, leading to difficult and inexact modeling of risk of release into seawater. Sulfur mustard and the organoarsenicals are the most environmentally persistent dumped chemical agents. Sulfur mustard in particular has a propensity to form a solid or semi-solid lump with a polymer coating of breakdown products, and can persist in this state on the ocean floor

Effects of anticaking agents and relative humidity on the physical and chemical stability of powdered vitamin C.

Science.gov (United States)

Lipasek, Rebecca A; Taylor, Lynne S; Mauer, Lisa J

2011-09-01

Vitamin C is an essential nutrient that is widely used by the food industry in the powder form for both its nutritional and functional properties. However, vitamin C is deliquescent, and deliquescence has been linked to physical and chemical instabilities. Anticaking agents are often added to powder systems to delay or prevent caking, but little is known about their effect on the chemical stability of powders. In this study, various anticaking agents (calcium phosphate, calcium silicate, calcium stearate, corn starch, and silicon dioxide) were combined with sodium ascorbate at 2% and 50% w/w ratios and stored at various relative humidities (23%, 43%, 64%, 75%, 85%, and 98% RHs). Chemical and physical stability and moisture sorption were monitored over time. Additionally, saturated solution samples were stored at various pHs to determine the effect of surface pH and dissolution on the vitamin degradation rate. Storage RH, time, and anticaking agent type and ratio all significantly affected (P vitamin C stability. Silicon dioxide and calcium silicate (50% w/w) and calcium stearate (at both ratios) were the only anticaking agents to improve the physical stability of powdered sodium ascorbate while none of the anticaking agents improved its chemical stability. However, corn starch and calcium stearate had the least adverse effect on chemical stability. Dissolution rate and pH were also important factors affecting the chemical and physical stability of the powders. Therefore, monitoring storage environmental conditions and anticaking agent usage are important for understanding the stability of vitamin C. Anticaking agent type and ratio significantly affected the physical and chemical stability of vitamin C over time and over a range of RHs. No anticaking agent improved the chemical stability of the vitamin, and most caused an increase in chemical degradation even if physical stability was improved. It is possible that anticaking agents would greatly affect other

Towards decomposition of live chemical agents by pyrotechnic mixtures

NARCIS (Netherlands)

Bouma, R.H.B.; Noort, D.

2012-01-01

The aim of this study is to contribute to improved EOD neutralisation techniques against improvised explosive devices (IEDs) containing chemical agents. The decomposition of dimethyl methylphosphonate (DMMP) when exposed to a burning aluminum/potassium nitrate pyrotechnic mixture is studied

[Persistent diarrhea

Science.gov (United States)

Andrade, J A; Moreira, C; Fagundes Neto, U

2000-07-01

INTRODUCTION: Persistent diarrhea has high impact on infantile morbidity and mortality rates in developing countries. Several studies have shown that 3 to 20% of acute diarrheal episodes in children under 5 years of age become persistent. DEFINITION: Persistent diarrhea is defined as an episode that lasts more than 14 days. ETIOLOGY: The most important agents isolated in persistent diarrhea are: Enteropathogenic E. coli (EPEC), Salmonella, Enteroaggregative E. coli (EAEC), Klebisiella and Cryptosporidium. CLINICAL ASPECTS: In general, the clinical characteristics of patients with persistent diarrhea do not change with the pathogenic agent. Persistent diarrhea seems to represent the final result of a several insults a infant suffers that predisposes to a more severe episode of diarrhea due to a combination of host factors and high rates of enviromental contamination. Therefore, efforts should be made to promptly treat all episodes of diarrhea with apropriate follow-up. THERAPY: The aim of the treatment is to restore hydroelectrolytic deficits and to replace losses until the diarrheal ceases. It is possible in the majority of the cases, using oral rehydration therapy and erly an appropriate type of diet. PREVENTION: It is imperative that management strategies also focus on preventive aspects. The most effective diarrheal prevention strategy in young infants worldwide is promotion of exclusive breast feeding.

Interspecific variation in persistence of buried weed seeds follows trade-offs among physiological, chemical, and physical seed defenses.

Science.gov (United States)

Davis, Adam S; Fu, Xianhui; Schutte, Brian J; Berhow, Mark A; Dalling, James W

2016-10-01

Soil seedbanks drive infestations of annual weeds, yet weed management focuses largely on seedling mortality. As weed seedbanks increasingly become reservoirs of herbicide resistance, species-specific seedbank management approaches will be essential to weed control. However, the development of seedbank management strategies can only develop from an understanding of how seed traits affect persistence.We quantified interspecific trade-offs among physiological, chemical, and physical traits of weed seeds and their persistence in the soil seedbank in a common garden study. Seeds of 11 annual weed species were buried in Savoy, IL, from 2007 through 2012. Seedling recruitment was measured weekly and seed viability measured annually. Seed physiological (dormancy), chemical (phenolic compound diversity and concentration; invertebrate toxicity), and physical traits (seed coat mass, thickness, and rupture resistance) were measured.Seed half-life in the soil ( t 0.5 ) showed strong interspecific variation ( F 10,30  = 15, p  central role of seed dormancy in controlling seed persistence.A quantitative comparison between our results and other published work indicated that weed seed dormancy and seedbank persistence are linked across diverse environments and agroecosystems. Moreover, among seedbank-forming early successional plant species, relative investment in chemical and physical seed defense varies with seedbank persistence. Synthesis and applications . Strong covariance among weed seed traits and persistence in the soil seedbank indicates potential for seedbank management practices tailored to specific weed species. In particular, species with high t 0.5 values tend to invest less in chemical defenses. This makes them highly vulnerable to physical harvest weed seed control strategies, with small amounts of damage resulting in their full decay.

Second NATO/SIBCA Exercise on Sampling of Chemical Warfare Agents

National Research Council Canada - National Science Library

Wils, E

1999-01-01

In order to practise the sampling of chemical warfare agents under realistic conditions, the Netherlands participated successfully in the second NATO/SIBCA sampling exercise conducted in Poland on 1-3...

Reevaluation of 1999 Health-Based Environmental Screening Levels (HBESLs) for Chemical Warfare Agents

Energy Technology Data Exchange (ETDEWEB)

Watson, Annetta Paule [ORNL; Dolislager, Fredrick G [ORNL

2007-05-01

This report evaluates whether new information and updated scientific models require that changes be made to previously published health-based environmental soil screening levels (HBESLs) and associated environmental fate/breakdown information for chemical warfare agents (USACHPPM 1999). Specifically, the present evaluation describes and compares changes that have been made since 1999 to U.S. Environmental Protection Agency (EPA) risk assessment models, EPA exposure assumptions, as well as to specific chemical warfare agent parameters (e.g., toxicity values). Comparison was made between screening value estimates recalculated with current assumptions and earlier health-based environmental screening levels presented in 1999. The chemical warfare agents evaluated include the G-series and VX nerve agents and the vesicants sulfur mustard (agent HD) and Lewisite (agent L). In addition, key degradation products of these agents were also evaluated. Study findings indicate that the combined effect of updates and/or changes to EPA risk models, EPA default exposure parameters, and certain chemical warfare agent toxicity criteria does not result in significant alteration to the USACHPPM (1999) health-based environmental screening level estimates for the G-series and VX nerve agents or the vesicant agents HD and L. Given that EPA's final position on separate Tier 1 screening levels for indoor and outdoor worker screening assessments has not yet been released as of May 2007, the study authors find that the 1999 screening level estimates (see Table ES.1) are still appropriate and protective for screening residential as well as nonresidential sites. As such, risk management decisions made on the basis of USACHPPM (1999) recommendations do not require reconsideration. While the 1999 HBESL values are appropriate for continued use as general screening criteria, the updated '2007' estimates (presented below) that follow the new EPA protocols currently under development

Evaluation of Chemical Warfare Agent Percutaneous Vapor Toxicity: Derivation of Toxicity Guidelines for Assessing Chemical Protective Ensembles.

Energy Technology Data Exchange (ETDEWEB)

Watson, A.P.

2003-07-24

Percutaneous vapor toxicity guidelines are provided for assessment and selection of chemical protective ensembles (CPEs) to be used by civilian and military first responders operating in a chemical warfare agent vapor environment. The agents evaluated include the G-series and VX nerve agents, the vesicant sulfur mustard (agent HD) and, to a lesser extent, the vesicant Lewisite (agent L). The focus of this evaluation is percutaneous vapor permeation of CPEs and the resulting skin absorption, as inhalation and ocular exposures are assumed to be largely eliminated through use of SCBA and full-face protective masks. Selection of appropriately protective CPE designs and materials incorporates a variety of test parameters to ensure operability, practicality, and adequacy. One aspect of adequacy assessment should be based on systems tests, which focus on effective protection of the most vulnerable body regions (e.g., the groin area), as identified in this analysis. The toxicity range of agent-specific cumulative exposures (Cts) derived in this analysis can be used as decision guidelines for CPE acceptance, in conjunction with weighting consideration towards more susceptible body regions. This toxicity range is bounded by the percutaneous vapor estimated minimal effect (EME{sub pv}) Ct (as the lower end) and the 1% population threshold effect (ECt{sub 01}) estimate. Assumptions of exposure duration used in CPE certification should consider that each agent-specific percutaneous vapor cumulative exposure Ct for a given endpoint is a constant for exposure durations between 30 min and 2 hours.

Modeling Dispersion of Chemical-Biological Agents in Three Dimensional Living Space

International Nuclear Information System (INIS)

William S. Winters

2002-01-01

This report documents a series of calculations designed to demonstrate Sandia's capability in modeling the dispersal of chemical and biological agents in complex three-dimensional spaces. The transport of particles representing biological agents is modeled in a single room and in several connected rooms. The influence of particle size, particle weight and injection method are studied

Biological and environmental hazards associated with exposure to chemical warfare agents: arsenicals.

Science.gov (United States)

Li, Changzhao; Srivastava, Ritesh K; Athar, Mohammad

2016-08-01

Arsenicals are highly reactive inorganic and organic derivatives of arsenic. These chemicals are very toxic and produce both acute and chronic tissue damage. On the basis of these observations, and considering the low cost and simple methods of their bulk syntheses, these agents were thought to be appropriate for chemical warfare. Among these, the best-known agent that was synthesized and weaponized during World War I (WWI) is Lewisite. Exposure to Lewisite causes painful inflammatory and blistering responses in the skin, lung, and eye. These chemicals also manifest systemic tissue injury following their cutaneous exposure. Although largely discontinued after WWI, stockpiles are still known to exist in the former Soviet Union, Germany, Italy, the United States, and Asia. Thus, access by terrorists or accidental exposure could be highly dangerous for humans and the environment. This review summarizes studies that describe the biological, pathophysiological, toxicological, and environmental effects of exposure to arsenicals, with a major focus on cutaneous injury. Studies related to the development of novel molecular pathobiology-based antidotes against these agents are also described. © 2016 New York Academy of Sciences.

Biological and environmental hazards associated with exposure to chemical warfare agents: arsenicals

Science.gov (United States)

Li, Changzhao; Srivastava, Ritesh K.; Athar, Mohammad

2016-01-01

Arsenicals are highly reactive inorganic and organic derivatives of arsenic. These chemicals are very toxic and produce both acute and chronic tissue damage. Based on these observations, and considering the low cost and simple methods of their bulk syntheses, these agents were thought to be appropriate for chemical warfare. Among these, the most known agent synthesized and weaponized during World War I (WWI) is Lewisite. Exposure to Lewisite causes painful inflammatory and blistering responses in the skin, lung, and eye. These chemicals also manifest systemic tissue injury following their cutaneous exposure. Although largely discontinued after WWI, their stockpiles are still known to exist in the former Soviet Union, Germany, Italy, the United States, and Asia. Thus, their access by terrorists or accidental exposure could be highly dangerous for humans and the environment. This review summarizes studies which describe the biological, pathophysiological, toxicological, and environmental effects of exposure to arsenicals, with a major focus on cutaneous injury. Studies related to the development of novel molecular pathobiology–based antidotes against these agents are also described. PMID:27636894

Decontamination and Detoxification of Toxic Chemical Warfare Agents Using Polyurethane Sponges

National Research Council Canada - National Science Library

Gordon, Richard K; Gunduz, Alper T; Askins, LaTawnya Y; Strating, Simon J; Doctor, Bhupendra P; Clarkson, Edward D; Mitchelree, Larry W; Lukey, Brian; Railer, Roy; Schulz, Susan

2003-01-01

.... Another serious problem that may be encountered while caring for personnel contaminated with organophosphorus chemical warfare nerve agents is the possibility that there will be cross-contamination...

Acute environmental toxicity and persistence of DEM, a chemical agent simulant: Diethyl malonate. [Diethyl malonate

Energy Technology Data Exchange (ETDEWEB)

Cataldo, D.A.; Ligotke, M.W.; Harvey, S.D.; Fellows, R.J.; Li, Shu-mei W.; Van Voris, P.; Wentsel, R.S.

1990-05-01

The purpose of the following chemical simulant studies is to assess the potential acute environmental effects and persistence of diethyl malonate (DEM). Deposition velocities for DEM to soil surfaces ranged from 0.04 to 0.2 cm/sec. For foliar surfaces, deposition velocities ranged from 0.0002 cm/sec at low air concentrations to 0.05 cm/sec for high dose levels. The residence times or half-lives of DEM deposited to soils was 2 h for the fast component and 5 to 16 h for the residual material. DEM deposited to foliar surfaces also exhibited biphasic depuration. The half-life of the short residence time component ranged from 1 to 3 h, while the longer time component had half-times of 16 to 242 h. Volatilization and other depuration mechanisms reduce surface contaminant levels in both soils and foliage to less than 1% of initial dose within 96 h. DEM is not phytotoxic at foliar mass loading levels of less than 10 {mu}m/cm{sup 2}. However, severe damage is evident at mass loading levels in excess of 17 {mu}g/cm{sup 2}. Tall fescue and sagebrush were more affected than was short-needle pine, however, mass loading levels were markedly different. Regrowth of tall fescue indicated that the effects of DEM are residual, and growth rates are affected only at higher mass loadings through the second harvest. Results from in vitro testing of DEM indicated concentrations below 500 {mu}g/g dry soil generally did not negatively impact soil microbial activity. Short-term effects of DEM were more profound on soil dehydrogenase activity than on soil phosphatase activity. No enzyme inhibition or enhancement was observed after 28 days in incubation. Results of the earthworm bioassay indicate survival to be 86 and 66% at soil doses of 107 and 204 {mu}g DEM/cm{sup 2}, respectively. At higher dose level, activity or mobility was judged to be affected in over 50% of the individuals. 21 refs., 10 figs., 15 tabs.

Sensitive and comprehensive detection of chemical warfare agents in air by atmospheric pressure chemical ionization ion trap tandem mass spectrometry with counterflow introduction.

Science.gov (United States)

Seto, Yasuo; Sekiguchi, Hiroshi; Maruko, Hisashi; Yamashiro, Shigeharu; Sano, Yasuhiro; Takayama, Yasuo; Sekioka, Ryoji; Yamaguchi, Shintaro; Kishi, Shintaro; Satoh, Takafumi; Sekiguchi, Hiroyuki; Iura, Kazumitsu; Nagashima, Hisayuki; Nagoya, Tomoki; Tsuge, Kouichiro; Ohsawa, Isaac; Okumura, Akihiko; Takada, Yasuaki; Ezawa, Naoya; Watanabe, Susumu; Hashimoto, Hiroaki

2014-05-06

A highly sensitive and specific real-time field-deployable detection technology, based on counterflow air introduction atmospheric pressure chemical ionization, has been developed for a wide range of chemical warfare agents (CWAs) comprising gaseous (two blood agents, three choking agents), volatile (six nerve gases and one precursor agent, five blister agents), and nonvolatile (three lachrymators, three vomiting agents) agents in air. The approach can afford effective chemical ionization, in both positive and negative ion modes, for ion trap multiple-stage mass spectrometry (MS(n)). The volatile and nonvolatile CWAs tested provided characteristic ions, which were fragmented into MS(3) product ions in positive and negative ion modes. Portions of the fragment ions were assigned by laboratory hybrid mass spectrometry (MS) composed of linear ion trap and high-resolution mass spectrometers. Gaseous agents were detected by MS or MS(2) in negative ion mode. The limits of detection for a 1 s measurement were typically at or below the microgram per cubic meter level except for chloropicrin (submilligram per cubic meter). Matrix effects by gasoline vapor resulted in minimal false-positive signals for all the CWAs and some signal suppression in the case of mustard gas. The moisture level did influence the measurement of the CWAs.

Using Benchmarking To Strengthen the Assessment of Persistence.

Science.gov (United States)

McLachlan, Michael S; Zou, Hongyan; Gouin, Todd

2017-01-03

Chemical persistence is a key property for assessing chemical risk and chemical hazard. Current methods for evaluating persistence are based on laboratory tests. The relationship between the laboratory based estimates and persistence in the environment is often unclear, in which case the current methods for evaluating persistence can be questioned. Chemical benchmarking opens new possibilities to measure persistence in the field. In this paper we explore how the benchmarking approach can be applied in both the laboratory and the field to deepen our understanding of chemical persistence in the environment and create a firmer scientific basis for laboratory to field extrapolation of persistence test results.

Identification system for chemical warfare agents with PGNAA method

International Nuclear Information System (INIS)

Wang Bairong; Yin Guanghua; Yang Zhongpin

2007-01-01

The principle and the experimental commanding of Chemical warfare Agents Identification with PGNAA method are discussed in this paper. The choosing of detector, neutron source and the data processing method are detailed. Finally, a set of experimental instruments composed of Cf-232 and BGO detector is developed based on this theory discussed above. (authors)

Alpha-hydroxyacid chemical peeling agents: case studies and rationale for safe and effective use.

Science.gov (United States)

Briden, M Elizabeth

2004-02-01

Chemical peeling is an in-office procedure that involves the application of a chemical agent to the skin to induce controlled destruction or exfoliation of old skin and stimulation of new epidermal growth with more evenly distributed melanin. When peel agents reach the dermal layer, important wound-healing activities occur that cause skin remodeling and skin smoothing, both antiaging benefits. There are a number of key factors in selecting a peeling agent and procedure, and each is discussed. Variables to consider are the peeling agent and its formulation, the concentration of the agent, the patient's skin type, the site to be peeled, the skin preparation procedure prior to and immediately preceding the application of the agent, the application method, the duration of contact, and the patient's medical history and lifestyle. Various types of peels are discussed. Of particular interest are superficial chemical peels, which offer great flexibility over a range of skin types and conditions with minimal to no "downtime." Alpha-hydroxyacid (AHA) peels are superficial and can be combined with other cosmetic procedures in the office to maximize benefits. In addition, AHA peels work well when combined with supportive homecare products including AHAs or polyhydroxy acids (PHAs), topical retinoids, and antiacne/antirosacea treatments. Case studies are presented of patients using AHA peels for the treatment of acne and hyperpigmentation in a variety of skin types, including Asian skin.

Sample Preparation and Identification of Biological, Chemical and Mid-Spectrum Agents

National Research Council Canada - National Science Library

Hancock, J. R; Dragon, D. C

2005-01-01

A general survey of sample preparation and identification techniques for biological, chemical and mid-spectrum agents was conducted as part of Canada's contribution to a joint NATO Allied Engineering Publication (AEP) handbook...

Neutralization of Aerosolized Bio-Agents by Filled Nanocomposite Materials through Thermal and Chemical Inactivation Mechanisms

Science.gov (United States)

2016-06-01

Bio -agents by Filled Nanocomposite Materials through Thermal and Chemical Inactivation Mechanisms Distribution Statement A. Approved for public...of Cincinnati Project Title: Neutralization of Aerosolized Bio -agents by Filled Nanocomposite Materials through Thermal and Chemical Inactivation...fire ball, where they will not effectively interact with any viable bio -aerosol. 1.1.4. Conclusions Cryo-milling is necessary to achieve a

PERMANENCE OF BIOLOGICAL AND CHEMICAL WARFARE AGENTS IN MUNICIPAL SOLID WASTE LANDFILL LEACHATES

Science.gov (United States)

The objective of this work is to permit EPA/ORD's National Homeland Security Research Center (NHSRC) and Edgewood Chemical Biological Center to collaborate together to test the permanence of biological and chemical warfare agents in municipal solid waste landfills. Research into ...

Persistence and concomitant medication in patients with overactive bladder treated with antimuscarinic agents in primary care. An observational baseline study.

Science.gov (United States)

Sicras-Mainar, A; Navarro-Artieda, R; Ruiz-Torrejón, A; Sáez-Zafra, M; Coll-de Tuero, G

2016-03-01

To assess therapeutic persistence and its relationship with concomitant medication in patients treated with fesoterodine versus tolterodine and solifenacin for overactive bladder (OAB) in standard clinical practice conditions. An observational, multicentre retrospective study was performed based on medical registries of patients followed-up in primary care (PC). Three study groups were analysed. Persistence was defined as the time (in months) without withdrawing from the initial therapy or without changing to another medication for at least 30 days after the initial prescription. The concomitant medications were antidepressants, anxiolytic/hypnotic agents, antibiotics, antiseptic agents, laxatives and skin products. We employed the SPSSWIN program version 17 (statistical significance, P<.05). We selected 3094 patients for the study. The median age was 54.0 years and 62.2% were women. The patients treated with fesoterodine shown greater treatment persistence (12 months) when compared with those who took solifenacin and tolterodine (40.2% vs. 34.7% and 33.6%, respectively; P=.008). They also showed a lower use of concomitant medication (1.1 vs. 1.2 and 1.2 drugs, respectively; percentages: 61.6% vs. 67.1% and 70.1%, respectively; P<.03). The patients undergoing OAB treatment with fesoterodine, when compared with those taking solifenacin and tolterodine, were associated with greater treatment persistence and a reduced use of concomitant medication. Copyright © 2015 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

A PMMA coated PMN–PT single crystal resonator for sensing chemical agents

International Nuclear Information System (INIS)

Frank, Michael; Kassegne, Sam; Moon, Kee S

2010-01-01

A highly sensitive lead magnesium niobate–lead titanate (PMN–PT) single crystal resonator coated with a thin film of polymethylmethacrylate (PMMA) useful for detecting chemical agents such as acetone, methanol, and isopropyl alcohol is presented. Swelling of the cured PMMA polymer layer in the presence of acetone, methanol, and isopropyl alcohol vapors is sensed as a mass change transduced to an electrical signal by the PMN–PT thickness shear mode sensor. Frequency change in the PMN–PT sensor is demonstrated to vary according to the concentration of the chemical vapor present within the sensing chamber. For acetone, the results indicate a frequency change more than 6000 times greater than that which would be expected from a quartz crystal microbalance coated with PMMA. This study is the first of its kind to demonstrate vapor loading of adsorbed chemical agents onto a polymer coated PMN–PT resonator

DRES Database of Methods for the Analysis of Chemical Warfare Agents

National Research Council Canada - National Science Library

D'Agostino, Paul

1997-01-01

.... Update of the database continues as an ongoing effort and the DRES Database of Methods for the Analysis of Chemical Warfare Agents is available panel in hardcopy form or as a softcopy Procite or Wordperfect file...

Chemical Agents

Science.gov (United States)

... CR) see Riot Control Agents Digitalis Distilled mustard (HD) see Sulfur mustard E Ethylene glycol F Fentanyls and other opioids H Hydrazine Hydrofluoric acid (hydrogen fluoride) Hydrogen chloride Hydrogen cyanide (AC) Hydrogen ...

Biodegradation of HT Agent from an Assembled Chemical Weapons Assessment (ACWA) Projectile Washout Study

National Research Council Canada - National Science Library

Guelta, Mark A

2006-01-01

In this study, HT agent, removed from a chemical round similar to the current stockpile stored at Pueblo Chemical Depot, was neutralized and the hydrolysate treated in a laboratory scale Immobilized Cell Bioreactor (ICB...

Audit Report. Johnston Atoll Chemical Agent Disposal System Preparation for Year 2000

National Research Council Canada - National Science Library

1998-01-01

.... The overall audit objective was to determine whether the Johnston Atoll Chemical Agent Disposal System was adequately preparing its information technology systems to resolve date-processing issues...

The efficacy of chemical agents in cleaning and disinfection programs

Directory of Open Access Journals (Sweden)

Silva Martins Alzira

2001-09-01

Full Text Available Abstract Background Due to the growing number of outbreaks of infection in hospital nurseries, it becomes essential to set up a sanitation program that indicates that the appropriate chemical agent was chosen for application in the most effective way. Method For the purpose of evaluating the efficacy of a chemical agent, the minimum inhibitory concentration (MIC was reached by the classic method of successive broth dilutions. The reference bacteria utilized were Bacillus subtilis var. globigii ATCC 9372, Bacillus stearothermophilus ATCC 7953, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923. The strains of Enterobacter cloacae IAL 1976 (Adolfo Lutz Institute, Serratia marcescens IAL 1478 and Acinetobactev calcoaceticus IAL 124 (ATCC 19606, were isolated from material collected from babies involved in outbreaks of infection in hospital nurseries. Results The MIC intervals, which reduced bacteria populations over 08 log10, were: 59 to 156 mg/L of quaternarium ammonium compounds (QACs; 63 to 10000 mg/L of chlorhexidine digluconate; 1375 to 3250 mg/L of glutaraldehyde; 39 to 246 mg/L of formaldehyde; 43750 to 87500 mg/L of isopropanol or ethanol; 1250 to 6250 mg/L of iodine in polyvinyl-pyrolidone complexes, 150 to 4491 mg/L of chlorine-releasing-agents (CRAs; 469 to 2500 mg/L of hydrogen peroxide; and, 2310 to 18500 mg/L of peracetic acid. Conclusions Chlorhexidine showed non inhibitory activity over germinating spores. A. calcoaceticus, was observed to show resistance to the majority of the agents tested, followed by E. cloacae and S. marcescens.

Modeling exposure to persistent chemicals in hazard and risk assessment.

Science.gov (United States)

Cowan-Ellsberry, Christina E; McLachlan, Michael S; Arnot, Jon A; Macleod, Matthew; McKone, Thomas E; Wania, Frank

2009-10-01

Fate and exposure modeling has not, thus far, been explicitly used in the risk profile documents prepared for evaluating the significant adverse effect of candidate chemicals for either the Stockholm Convention or the Convention on Long-Range Transboundary Air Pollution. However, we believe models have considerable potential to improve the risk profiles. Fate and exposure models are already used routinely in other similar regulatory applications to inform decisions, and they have been instrumental in building our current understanding of the fate of persistent organic pollutants (POP) and persistent, bioaccumulative, and toxic (PBT) chemicals in the environment. The goal of this publication is to motivate the use of fate and exposure models in preparing risk profiles in the POP assessment procedure by providing strategies for incorporating and using models. The ways that fate and exposure models can be used to improve and inform the development of risk profiles include 1) benchmarking the ratio of exposure and emissions of candidate chemicals to the same ratio for known POPs, thereby opening the possibility of combining this ratio with the relative emissions and relative toxicity to arrive at a measure of relative risk; 2) directly estimating the exposure of the environment, biota, and humans to provide information to complement measurements or where measurements are not available or are limited; 3) to identify the key processes and chemical or environmental parameters that determine the exposure, thereby allowing the effective prioritization of research or measurements to improve the risk profile; and 4) forecasting future time trends, including how quickly exposure levels in remote areas would respond to reductions in emissions. Currently there is no standardized consensus model for use in the risk profile context. Therefore, to choose the appropriate model the risk profile developer must evaluate how appropriate an existing model is for a specific setting and

Mutagenic effect of ionizing radiation and chemical and environmental agents in Tradescantia

International Nuclear Information System (INIS)

Cebulska-Wasilewska, A.

1988-01-01

The studies covered the following problems: an influence of some environmental agents on the mutagenic effectiveness of ionizing radiation, interaction between ionizing radiation and chemical mutagens in the induction of somatic mutations and also an application of Tradescantia model system for biological monitoring. The studies showed that the pretreatment of Tradescantia plants with sodium fluoride or the modification of the soil composition with dolomite admixture, visibly influences plants radiosensitivity. The analysis of the changes in the dose-response curves suggested that the employed agents were influencing in different ways the repair processes of the DNA. The studies on the interaction between agents proved that the synergistic effect occurs in case of combined action of ionizing radiation with such chemical mutagens as ethyl methansulfonate or 1,2 dibromomethane. It was also discovered that in the range of low doses the effect was proportional to radiation dose and total exposition to chemical mutagen. The field application of Tradescantia method defined the mutagenicity of air pollution in the Cracow area. The highest frequencies of mutations were detected after the Chernobyl accident and after the damage of the filters in the Pharmaceutical Plant. The applied method was evaluated in respect of its usefulness for biological monitoring of environmental pollution. 163 refs. (author)

Reactive skin decontamination lotion (RSDL) for the decontamination of chemical warfare agent (CWA) dermal exposure.

Science.gov (United States)

Schwartz, M D; Hurst, C G; Kirk, M A; Reedy, S J D; Braue, E H

2012-08-01

Rapid decontamination of the skin is the single most important action to prevent dermal absorption of chemical contaminants in persons exposed to chemical warfare agents (CWA) and toxic industrial chemicals (TICs) as a result of accidental or intentional release. Chemicals on the skin may be removed by mechanical means through the use of dry sorbents or water. Recent interest in decontamination systems which both partition contaminants away from the skin and actively neutralize the chemical has led to the development of several reactive decontamination solutions. This article will review the recently FDA-approved Reactive Skin Decontamination Lotion (RSDL) and will summarize the toxicity and efficacy studies conducted to date. Evidence of RSDL's superior performance against vesicant and organophosphorus chemical warfare agents compared to water, bleach, and dry sorbents, suggests that RSDL may have a role in mass human exposure chemical decontamination in both the military and civilian arenas.

Detection of Chemical/Biological Agents and Stimulants using Quadrupole Ion Trap Mass Spectrometry

International Nuclear Information System (INIS)

Harmon, S.H.; Hart, K.J.; Vass, A.A.; Wise, M.B.; Wolf, D.A.

1999-01-01

Detection of Chemical/Biological Agents and Simulants A new detector for chemical and biological agents is being developed for the U. S. Army under the Chemical and Biological Mass Spectrometer Block II program. The CBMS Block II is designed to optimize detection of both chemical and biological agents through the use of direct sampling inlets[I], a multi- ported sampling valve and a turbo- based vacuum system to support chemical ionization. Unit mass resolution using air as the buffer gas[2] has been obtained using this design. Software to control the instrument and to analyze the data generated from the instrument has also been newly developed. Detection of chemical agents can be accomplished. using the CBMS Block II design via one of two inlets - a l/ I 6'' stainless steel sample line -Chemical Warfare Air (CW Air) or a ground probe with enclosed capillary currently in use by the US Army - CW Ground. The Block II design is capable of both electron ionization and chemical ionization. Ethanol is being used as the Cl reagent based on a study indicating best performance for the Biological Warfare (BW) detection task (31). Data showing good signal to noise for 500 pg of methyl salicylate injected into the CW Air inlet, 50 ng of dimethylmethylphosphonate exposed to the CW Ground probe and 5 ng of methyl stearate analyzed using the pyrolyzer inlet were presented. Biological agents are sampled using a ''bio-concentrator'' unit that is designed to concentrate particles in the low micron range. Particles are collected in the bottom of a quartz pyrolyzer tube. An automated injector is being developed to deliver approximately 2 pL of a methylating reagent, tetramethylamonium- hydroxide to 'the collected particles. Pyrolysis occurs by rapid heating to ca. 55OOC. Biological agents are then characterized by their fatty acid methyl ester profiles and by other biomarkers. A library of ETOH- Cl/ pyrolysis MS data of microorganisms used for a recently published study[3] has been

Testing Dust Control Preparation with Respect to Mine Employee Exposure to Inhalling Chemical Agents

Directory of Open Access Journals (Sweden)

Eugeniusz Orszulik

2013-01-01

Full Text Available This paper presents the results of tests used in dust hazard prevention for air-water spraying devices in collieries. The purpose of the tests was to evaluate mine employees’ exposure to inhalling chemical agents when the ZWILKOP ZW-10 preparation is used. The paper presents the results of the measurements of concentration, in a mine atmosphere, of the following chemical agents: hazardous substances 2-(2-butoxyethoxyethanol and 2-ethylhexan-1-ol, constituting ingredients of the preparation at mine employees’ workstations. The tests were performed during work related to the mining of coal in inclined drift C31, seam 415/1-2 on the premises of “Borynia-Zofiówka-Jastrzębie” Hard Coal Mine, Jastrzębie-Zdrój, Poland, using the TELESTO mist systems. Using aqueous solutions for the preparation at concentrations of 15 and 20‰ causes no exceedance of the allowable mine air concentrations for the chemical agents tested.

Rain-Induced Wash-Off of Chemical Warfare Agent (VX) from Foliar Surfaces of Living Plants Maintained in a Surety Hood

Science.gov (United States)

2016-09-01

RAIN-INDUCED WASH-OFF OF CHEMICAL WARFARE AGENT (VX) FROM FOLIAR SURFACES OF LIVING PLANTS MAINTAINED IN A...Final 3. DATES COVERED (From - To) May 2014 – Sep 2015 4. TITLE AND SUBTITLE Rain-Induced Wash-Off of Chemical Warfare Agent (VX) from Foliar...galli Foliage Chemical warfare agent (CWA) O-ethyl-S-(2

Accelerating the degradation of green plant waste with chemical decomposition agents.

Science.gov (United States)

Kejun, Sun; Juntao, Zhang; Ying, Chen; Zongwen, Liao; Lin, Ruan; Cong, Liu

2011-10-01

Degradation of green plant waste is often difficult, and excess maturity times are typically required. In this study, we used lignin, cellulose and hemicellulose assays; scanning electron microscopy; infrared spectrum analysis and X-ray diffraction analysis to investigate the effects of chemical decomposition agents on the lignocellulose content of green plant waste, its structure and major functional groups and the mechanism of accelerated degradation. Our results showed that adding chemical decomposition agents to Ficus microcarpa var. pusillifolia sawdust reduced the contents of lignin by 0.53%-11.48% and the contents of cellulose by 2.86%-7.71%, and increased the contents of hemicellulose by 2.92%-33.63% after 24 h. With increasing quantities of alkaline residue and sodium lignosulphonate, the lignin content decreased. Scanning electron microscopy showed that, after F. microcarpa var. pusillifolia sawdust was treated with chemical decomposition agents, lignocellulose tube wall thickness increased significantlyIncreases of 29.41%, 3.53% and 34.71% were observed after treatment with NaOH, alkaline residue and sodium lignosulphonate, respectively. Infrared spectroscopy showed that CO and aromatic skeleton stretching absorption peaks were weakened and the C-H vibrational absorption peak from out-of-plane in positions 2 and 6 (S units) (890-900 cm(-1)) was strengthened after F. microcarpa var. pusillifolia sawdust was treated with chemical decomposition agents, indicating a reduction in lignin content. Several absorption peaks [i.e., C-H deformations (asymmetry in methyl groups, -CH(3)- and -CH(2)-) (1450-1460 cm(-1)); Aliphatic C-H stretching in methyl and phenol OH (1370-1380 cm(-1)); CO stretching (cellulose and hemicellulose) (1040-1060 cm(-1))] that indicate the presence of a chemical bond between lignin and cellulose was reduced, indicating that the chemical bond between lignin and cellulose had been partially broken. X-ray diffraction analysis showed that Na

Nanostructured Metal Oxides for Stoichiometric Degradation of Chemical Warfare Agents

Czech Academy of Sciences Publication Activity Database

Štengl, Václav; Henych, Jiří; Janos, P.; Skoumal, M.

2016-01-01

Roč. 236, č. 2016 (2016), s. 239-258 ISSN 0179-5953 R&D Projects: GA ČR(CZ) GAP106/12/1116 Institutional support: RVO:61388980 Keywords : chemical warfare agent * metal nanoparticle * unique surface- chemistry * mesoporous manganese oxide Subject RIV: CA - Inorganic Chemistry Impact factor: 3.930, year: 2016

Chemical analysis of bleach and hydroxide-based solutions after decontamination of the chemical warfare agent O-ethyl S-2-diisopropylaminoethyl methylphosphonothiolate (VX).

Science.gov (United States)

Hopkins, F B; Gravett, M R; Self, A J; Wang, M; Chua, Hoe-Chee; Hoe-Chee, C; Lee, H S Nancy; Sim, N Lee Hoi; Jones, J T A; Timperley, C M; Riches, J R

2014-08-01

Detailed chemical analysis of solutions used to decontaminate chemical warfare agents can be used to support verification and forensic attribution. Decontamination solutions are amongst the most difficult matrices for chemical analysis because of their corrosive and potentially emulsion-based nature. Consequently, there are relatively few publications that report their detailed chemical analysis. This paper describes the application of modern analytical techniques to the analysis of decontamination solutions following decontamination of the chemical warfare agent O-ethyl S-2-diisopropylaminoethyl methylphosphonothiolate (VX). We confirm the formation of N,N-diisopropylformamide and N,N-diisopropylamine following decontamination of VX with hypochlorite-based solution, whereas they were not detected in extracts of hydroxide-based decontamination solutions by nuclear magnetic resonance (NMR) spectroscopy or gas chromatography-mass spectrometry. We report the electron ionisation and chemical ionisation mass spectroscopic details, retention indices, and NMR spectra of N,N-diisopropylformamide and N,N-diisopropylamine, as well as analytical methods suitable for their analysis and identification in solvent extracts and decontamination residues.

Ultrasensitive detection of explosives and chemical warfare agents by low-pressure photoionization mass spectrometry.

Science.gov (United States)

Sun, Wanqi; Liang, Miao; Li, Zhen; Shu, Jinian; Yang, Bo; Xu, Ce; Zou, Yao

2016-08-15

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. Copyright © 2016 Elsevier B.V. All rights reserved.

A review on common chemical hemostatic agents in restorative dentistry

Directory of Open Access Journals (Sweden)

Pardis Tarighi

2014-01-01

Full Text Available Control of hemorrhage is one of the challenging situations dentists confront during deep cavity preparation and before impressions or cementation of restorations. For the best bond and least contamination it is necessary to be familiar with the hemostatic agents available on the market and to be able to choose the appropriate one for specific situations. This review tries to introduce the commercially available hemostatic agents, discusses their components and their specific features. The most common chemical agents that are widely used in restorative and prosthodontic dentistry according to their components and mechanism of action as well as their special uses are introduced. PubMed and Google Scholar were searched for studies involving gingival retraction and hemostatic agents from 1970 to 2013. Key search words including: "gingival retraction techniques, impression technique, hemostasis and astringent" were searched. Based on the information available in the literature, in order to achieve better results with impression taking and using resin bonding techniques, common hemostatic agents might be recommended before or during acid etching; they should be rinsed off properly and it is recommended that they be used with etch-and-rinse adhesive systems.

Project Swiftsure final report: Destruction of chemical agent waste at Defence Research Establishment Suffield. Special publication

Energy Technology Data Exchange (ETDEWEB)

McAndless, J.M.

1994-04-01

Project Swiftsure describes a three-year project at the Defence Research Establishment Suffield to safely destroy stockpiles of mustard lewisite, nerve agents and decontaminate scrap material which was stored on the DRES Experimental Proving Ground. Using both in-house and contracted resources, the agent waste was destroyed by chemical neutralization or incineration. With the exception of the arsenic byproducts from the lewisite neutralization process, all secondary waste generated by chemical neutralization was incinerated. Mustard in different forms was thermally destroyed using a transportable incinerator of commercial design. Extensive environmental monitoring and public consultation programs were conducted during the project. Results of the monitoring programs verified that the chemical warfare agents were destroyed in a safe, environmentally-responsible manner. jg p.329.

Functionalized gold nanoparticle supported sensory mechanisms applied in detection of chemical and biological threat agents: A review

International Nuclear Information System (INIS)

Upadhyayula, Venkata K.K.

2012-01-01

Highlights: ► Smart sensors are needed for detection of chemical and biological threat agents. ► Smart sensors detect analytes with rapid speed, high sensitivity and selectivity. ► Functionalized gold nanoparticles (GNPs) can potentially smart sense threat agents. ► Functionalized GNPs support multiple analytical methods for sensing threat agents. ► Threat agents of all types can be detected using functionalized GNPs. - Abstract: There is a great necessity for development of novel sensory concepts supportive of smart sensing capabilities in defense and homeland security applications for detection of chemical and biological threat agents. A smart sensor is a detection device that can exhibit important features such as speed, sensitivity, selectivity, portability, and more importantly, simplicity in identifying a target analyte. Emerging nanomaterial based sensors, particularly those developed by utilizing functionalized gold nanoparticles (GNPs) as a sensing component potentially offer many desirable features needed for threat agent detection. The sensitiveness of physical properties expressed by GNPs, e.g. color, surface plasmon resonance, electrical conductivity and binding affinity are significantly enhanced when they are subjected to functionalization with an appropriate metal, organic or biomolecular functional groups. This sensitive nature of functionalized GNPs can be potentially exploited in the design of threat agent detection devices with smart sensing capabilities. In the presence of a target analyte (i.e., a chemical or biological threat agent) a change proportional to concentration of the analyte is observed, which can be measured either by colorimetric, fluorimetric, electrochemical or spectroscopic means. This article provides a review of how functionally modified gold colloids are applied in the detection of a broad range of threat agents, including radioactive substances, explosive compounds, chemical warfare agents, biotoxins, and

Functionalized gold nanoparticle supported sensory mechanisms applied in detection of chemical and biological threat agents: A review

Energy Technology Data Exchange (ETDEWEB)

Upadhyayula, Venkata K.K., E-mail: Upadhyayula.Venkata@epa.gov [Oak Ridge Institute of Science and Education (ORISE), MC-100-44, PO Box 117, Oak Ridge, TN 37831 (United States)

2012-02-17

Highlights: Black-Right-Pointing-Pointer Smart sensors are needed for detection of chemical and biological threat agents. Black-Right-Pointing-Pointer Smart sensors detect analytes with rapid speed, high sensitivity and selectivity. Black-Right-Pointing-Pointer Functionalized gold nanoparticles (GNPs) can potentially smart sense threat agents. Black-Right-Pointing-Pointer Functionalized GNPs support multiple analytical methods for sensing threat agents. Black-Right-Pointing-Pointer Threat agents of all types can be detected using functionalized GNPs. - Abstract: There is a great necessity for development of novel sensory concepts supportive of smart sensing capabilities in defense and homeland security applications for detection of chemical and biological threat agents. A smart sensor is a detection device that can exhibit important features such as speed, sensitivity, selectivity, portability, and more importantly, simplicity in identifying a target analyte. Emerging nanomaterial based sensors, particularly those developed by utilizing functionalized gold nanoparticles (GNPs) as a sensing component potentially offer many desirable features needed for threat agent detection. The sensitiveness of physical properties expressed by GNPs, e.g. color, surface plasmon resonance, electrical conductivity and binding affinity are significantly enhanced when they are subjected to functionalization with an appropriate metal, organic or biomolecular functional groups. This sensitive nature of functionalized GNPs can be potentially exploited in the design of threat agent detection devices with smart sensing capabilities. In the presence of a target analyte (i.e., a chemical or biological threat agent) a change proportional to concentration of the analyte is observed, which can be measured either by colorimetric, fluorimetric, electrochemical or spectroscopic means. This article provides a review of how functionally modified gold colloids are applied in the detection of a broad

A identification system for chemical warfare agents with PGNAA method

International Nuclear Information System (INIS)

Wang Bairong; Yin Guanghua; Yang Zhongping

2006-01-01

The principle and the experimental commanding of Chemical warfare Agents Identification with PGNAA method are discussed in this paper. The choosing of Detector, neutron source and the data processing method are detailed. Finally, a set of experimental instruments composed of Cf-232 and BGO detector is developed based on the theory discussed above. (authors)

Screening of chemical compound libraries identified new anti-Toxoplasma gondii agents.

Science.gov (United States)

Adeyemi, Oluyomi Stephen; Sugi, Tatsuki; Han, Yongmei; Kato, Kentaro

2018-02-01

Toxoplasma gondii is the etiological agent of toxoplasmosis, a common parasitic disease that affects nearly one-third of the human population. The primary infection can be asymptomatic in healthy individuals but may prove fatal in immunocompromised individuals. Available treatment options for toxoplasmosis patients are limited, underscoring the urgent need to identify and develop new therapies. Non-biased screening of libraries of chemical compounds including the repurposing of well-characterized compounds is emerging as viable approach to achieving this goal. In the present investigation, we screened libraries of natural product and FDA-approved compounds to identify those that inhibited T. gondii growth. We identified 32 new compounds that potently inhibit T. gondii growth. Our findings are new and promising, and further strengthen the prospects of drug repurposing as well as the screening of a wide range of chemical compounds as a viable source of alternative anti-parasitic therapeutic agents.

Plasma flame for mass purification of contaminated air with chemical and biological warfare agents

International Nuclear Information System (INIS)

Uhm, Han S.; Shin, Dong H.; Hong, Yong C.

2006-01-01

An elimination of airborne simulated chemical and biological warfare agents was carried out by making use of a plasma flame made of atmospheric plasma and a fuel-burning flame, which can purify the interior air of a large volume in isolated spaces such as buildings, public transportation systems, and military vehicles. The plasma flame generator consists of a microwave plasma torch connected in series to a fuel injector and a reaction chamber. For example, a reaction chamber, with the dimensions of a 22 cm diameter and 30 cm length, purifies an airflow rate of 5000 lpm contaminated with toluene (the simulated chemical agent) and soot from a diesel engine (the simulated aerosol for biological agents). Large volumes of purification by the plasma flame will free mankind from the threat of airborne warfare agents. The plasma flame may also effectively purify air that is contaminated with volatile organic compounds, in addition to eliminating soot from diesel engines as an environmental application

Distribution of chemical warfare agent, energetics, and metals in sediments at a deep-water discarded military munitions site

Science.gov (United States)

Briggs, Christian; Shjegstad, Sonia M.; Silva, Jeff A. K.; Edwards, Margo H.

2016-06-01

There is a strong need to understand the behavior of chemical warfare agent (CWA) at underwater discarded military munitions (DMM) sites to determine the potential threat to human health or the environment, yet few studies have been conducted at sites in excess of 250 m, the depth at which most U.S. chemical munitions were disposed. As part of the Hawai'i Undersea Military Munitions Assessment (HUMMA), sediments adjacent to chemical and conventional DMM at depths of 400-650 m were sampled using human occupied vehicles (HOVs) in order to quantify the distribution of CWA, energetics, and select metals. Sites in the same general area, with no munitions within 50 m in any direction were sampled as a control. Sulfur mustard (HD) and its degradation product 1,4-dithiane were detected at each CWA DMM site, as well as a single sample with the HD degradation product 1,4-thioxane. An energetic compound was detected in sediment to a limited extent at one CWA DMM site. Metals common in munitions casings (i.e., Fe, Cu, and Pb) showed similar trends at the regional and site-wide scales, likely reflecting changes in marine sediment deposition and composition. This study shows HD and its degradation products can persist in the deep-marine environment for decades following munitions disposal.

Personal protection during resuscitation of casualties contaminated with chemical or biological warfare agents--a survey of medical first responders.

Science.gov (United States)

Brinker, Andrea; Prior, Kate; Schumacher, Jan

2009-01-01

The threat of mass casualties caused by an unconventional terrorist attack is a challenge for the public health system, with special implications for emergency medicine, anesthesia, and intensive care. Advanced life support of patients injured by chemical or biological warfare agents requires an adequate level of personal protection. The aim of this study was to evaluate the personal protection knowledge of emergency physicians and anesthetists who would be at the frontline of the initial health response to a chemical/biological warfare agent incident. After institutional review board approval, knowledge of personal protection measures among emergency medicine (n = 28) and anesthetics (n = 47) specialty registrars in the South Thames Region of the United Kingdom was surveyed using a standardized questionnaire. Participants were asked for the recommended level of personal protection if a chemical/biological warfare agent(s) casualty required advanced life support in the designated hospital resuscitation area. The best awareness within both groups was regarding severe acute respiratory syndrome, and fair knowledge was found regarding anthrax, plague, Ebola, and smallpox. In both groups, knowledge about personal protection requirements against chemical warfare agents was limited. Knowledge about personal protection measures for biological agents was acceptable, but was limited for chemical warfare agents. The results highlight the need to improve training and education regarding personal protection measures for medical first receivers.

Evaluation of the persistence in the induction of Sister Chromatid Exchanges (SCE) by alkylating agents; Evaluacion de la persistencia en la induccion de Intercambio en las Cromatidas Hermanas (ICH) por agentes alquilantes

Energy Technology Data Exchange (ETDEWEB)

Rodriguez R, R.; Huerta V, C.; MOrales R, P.R. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

2006-07-01

The persistence in the induction of sister chromatid exchanges (SCE) by the alkylating agents methyl and ethyl-methanesulfonates (MMS and EMS) was evaluated. For it, to groups of mice its were administered a dose of these agents and later its were analyzed the induced SCE's in two periods: early and late. Both agents caused high increments of SCE in the early period and small in the late one; however, the caused lately by EMS was significantly bigger. This late induction of SCE by EMS possibly is associated with an epigenetic change or with the presence of etiladucts in the phosphodiester bonds of the DNA. (Author)

Evaluation of the persistence in the induction of Sister Chromatid Exchanges (SCE) by alkylating agents; Evaluacion de la persistencia en la induccion de Intercambio en las Cromatidas Hermanas (ICH) por agentes alquilantes

Energy Technology Data Exchange (ETDEWEB)

Rodriguez R, R; Huerta V, C; MOrales R, P R [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

2006-07-01

The persistence in the induction of sister chromatid exchanges (SCE) by the alkylating agents methyl and ethyl-methanesulfonates (MMS and EMS) was evaluated. For it, to groups of mice its were administered a dose of these agents and later its were analyzed the induced SCE's in two periods: early and late. Both agents caused high increments of SCE in the early period and small in the late one; however, the caused lately by EMS was significantly bigger. This late induction of SCE by EMS possibly is associated with an epigenetic change or with the presence of etiladucts in the phosphodiester bonds of the DNA. (Author)

Behavioral determinants of occupational exposure to chemical agents.

Science.gov (United States)

Meijman, T F; Ulenbelt, P; Lumens, M E; Herber, R F

1996-01-01

In the demand-control model (see T. Theorell & R. A. Karasek, 1996), it is hypothesized that workers in active jobs (high demands-high decision latitude) can exert effective coping strategies when confronted with environmental stessors. Thus, when exposed to similar levels of a chemical agent, lower concentrations of this agent in blood could be expected in these workers in comparison with workers in passive jobs. This theory was tested in 2 studies of lead-exposed workers: 18 male Caucasian workers from an electric accumulatory factory and 18 male Caucasian workers from a lead smelting factory. The results did not follow the hypothesized outcomes. In the work environment of the workers in active jobs, lower concentrations of lead in air were measured, but higher levels of lead in blood were observed in these workers. The opposite was true of workers in passive jobs. Differences in hygienic behavior at work may explain these unexpected results.

Textile/metal-organic-framework composites as self-detoxifying filters for chemical-warfare agents.

Science.gov (United States)

López-Maya, Elena; Montoro, Carmen; Rodríguez-Albelo, L Marleny; Aznar Cervantes, Salvador D; Lozano-Pérez, A Abel; Cenís, José Luis; Barea, Elisa; Navarro, Jorge A R

2015-06-01

The current technology of air-filtration materials for protection against highly toxic chemicals, that is, chemical-warfare agents, is mainly based on the broad and effective adsorptive properties of hydrophobic activated carbons. However, adsorption does not prevent these materials from behaving as secondary emitters once they are contaminated. Thus, the development of efficient self-cleaning filters is of high interest. Herein, we report how we can take advantage of the improved phosphotriesterase catalytic activity of lithium alkoxide doped zirconium(IV) metal-organic framework (MOF) materials to develop advanced self-detoxifying adsorbents of chemical-warfare agents containing hydrolysable P-F, P-O, and C-Cl bonds. Moreover, we also show that it is possible to integrate these materials onto textiles, thereby combining air-permeation properties of the textiles with the self-detoxifying properties of the MOF material. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Environmental assessments of sea dumped chemical warfare agents

DEFF Research Database (Denmark)

Sanderson, Hans; Fauser, Patrik

This is a report on the information gathered during work related to sea dumped chemical warfare agents. It mainly reviews the work conducted in relation to the installation of the two Nord Stream gas pipeline from 2008-2012. The focus was on the weight-of-evidence risk assessment of disturbed CWA...... residues in connection with the installation of the pipelines. Novel exposure and toxicity assessments are presented and the risk is assessed. The overall conclusion is that there is a negligible acute added CWA risk towards the fish community from the installation of the pipelines....

Identification of Chemical Agents (Mimics) Residues after Destructive Adsorption Using TPD and UV-vis-IR and Raman

National Research Council Canada - National Science Library

Klabunde, Kenneth J

2001-01-01

Instrumentation was purchased that helps characterize the chemical structures and chemical reactions that occur when nanocrystalline metal oxides carry out destructive adsorption of chemical agents mimics. The residues (adducts...

Overview on Analysis of Free Metabolites for Detection of Exposure to Chemical Warfare Agents

Directory of Open Access Journals (Sweden)

Grigoriu Nicoleta

2015-06-01

Full Text Available Chemical warfare agents (CWA’s induce complex toxicological effects with major adverse consequences for those exposed. For many chemical agents there is a need for research and development of analytical toxicological methods for a rapid and certain confirmation of those exposures. The certain methods will help for establishing the laboratory diagnosis for applying the proper therapy; the treatment of only contaminated people, decreasing the stress level in the medical community in management of crisis situations, increasing the survival rate of the population exposed to the contamination, supervision of professional exposure, judicial analysis in case of suspicious terrorist activities.

An agent-based simulation of persistent inequalities in health behavior: Understanding the interdependent roles of segregation, clustering, and social influence.

Science.gov (United States)

Langellier, Brent A

2016-12-01

Health inequalities are conspicuously persistent through time and often durable even in spite of interventions. In this study, I use agent-based simulation models (ABMs) to understand how the complex interrelationships between residential segregation, social network formation, group-level preferences, and social influence may contribute to this persistence. I use a more-stylized ABM, Bubblegum Village (BV), to understand how initial inequalities in bubblegum-chewing behaviors either endure, increase, or decrease over time given group-level differences in preferences, neighborhood-level barriers or facilitators of bubblegum chewing (e.g., access to bubblegum shops), and agents' preferences for segregation, homophily, and clustering (i.e., the 'tightness' of social networks). I further use BV to understand whether segregation and social network characteristics impact whether the effects of a bubblegum-reduction intervention that is very effective in the short term are durable over time, as well as to identify intervention strategies to reduce attenuation of the intervention effects. In addition to BV, I also present results from an ABM based on the distribution and social characteristics of the population in Philadelphia, PA. This model explores similar questions to BV, but examines racial/ethnic inequalities in soda consumption based on agents' social characteristics and baseline soda consumption probabilities informed by the 2007-2010 National Health and Nutrition Examination Survey. Collectively, the models suggest that residential segregation is a fundamental process for the production and persistence of health inequalities. The other major conclusion of the study is that, for behaviors that are subject to social influence and that cluster within social groups, interventions that are randomly-targeted to individuals with 'bad' behaviors will likely experience a large degree of recidivism to pre-intervention behaviors. In contrast, interventions that target

Development of Bicarbonate-Activated Peroxide as a Chemical and Biological Warfare Agent Decontaminant

National Research Council Canada - National Science Library

Richardson, David E

2006-01-01

...) and other chemistry for the decontamination of chemical and biological warfare agents. The mechanism of formation of the active oxidant, peroxymonocarbonate, has been investigated in detail. New surfoxidants...

Reentry planning: The technical basis for offsite recovery following warfare agent contamination

Energy Technology Data Exchange (ETDEWEB)

Watson, A.P.; Munro, N.B.

1990-04-01

In the event on an unplanned release of chemical agent during any stage of Chemical Stockpile Disposal Program (CSDP), the potential exists for contamination of drinking water, forage crops, grains, garden produce and livestock. Persistent agents, such as VX or sulfur mustard, pose the greatest human health concern for reentry. The purpose of this technical support study is to provide information and analyses that can be used by federal, state and local emergency planners in determining the safety or reentry to, as well as the potential for recovery of, contaminated or suspect areas beyond the installation boundary. Guidelines for disposition of livestock, agricultural crops and personal/real property are summarized. Advisories for ingestion of food crops, water, meat and milk from the affected zones are proposed. This document does not address potential adverse effects to, or agent contamination of, wild species of plants or animals. 80 refs., 4 figs., 29 tabs.

The importance of chemical components in cleaning agents for the indoor environment

DEFF Research Database (Denmark)

Vejrup, Karl Ventzel

In order to evaluate the importance for the indoor environment of chemical compounds in cleaning agents, the emission of VOCs (Volatile Organic Compounds) from 10 selected cleaning agents and the content of LAS (Linear AlkanbenzeneSulfonate) in dust samples from 7 buildings were investigated.The...... of LAS between smooth floored corridors to carpeted offices, are apparently also of importance for the LAS content in individual rooms.The amounts of LAS found in the dust samples indicated that LAS may be of importance for the indoor environment, but inadequate knowledge about how low concentrations...... investigation of VOC emission from 10 selected cleaning agents showed that it was useful to classify the VOCs into two groups: nonpolar VOCs and polar VOCs.The nonpolar VOCs consisted of several hundred different compounds, mainly terpenes typically used as perfume in cleaning agents. The nonpolar VOC...

Negative affect is associated with development and persistence of chemical intolerance

DEFF Research Database (Denmark)

Skovbjerg, Sine; Christensen, Karl Bang; Ebstrup, Jeanette Frost

2015-01-01

. METHODS: A general population sample aged 19 to 72years was examined in 2006-2008 and again in 2011-2012. Longitudinal data on CI were analysed with the purpose of examining baseline negative affect as a risk factor for having developed CI at 5-year follow-up and for reporting persistent CI. Participants.......4% of the participants who had reported CI at baseline also reported CI at follow-up. In participants with no baseline CI, 15.5% reported CI at follow-up and 18.1% reported symptoms related to chemicals but no daily life adjustments. Baseline negative affect was positively and statistically significantly associated...

Activation of aluminum as an effective reducing agent by pitting corrosion for wet-chemical synthesis.

Science.gov (United States)

Li, Wei; Cochell, Thomas; Manthiram, Arumugam

2013-01-01

Metallic aluminum (Al) is of interest as a reducing agent because of its low standard reduction potential. However, its surface is invariably covered with a dense aluminum oxide film, which prevents its effective use as a reducing agent in wet-chemical synthesis. Pitting corrosion, known as an undesired reaction destroying Al and is enhanced by anions such as F⁻, Cl⁻, and Br⁻ in aqueous solutions, is applied here for the first time to activate Al as a reducing agent for wet-chemical synthesis of a diverse array of metals and alloys. Specifically, we demonstrate the synthesis of highly dispersed palladium nanoparticles on carbon black with stabilizers and the intermetallic Cu₂Sb/C, which are promising candidates, respectively, for fuel cell catalysts and lithium-ion battery anodes. Atomic hydrogen, an intermediate during the pitting corrosion of Al in protonic solvents (e.g., water and ethylene glycol), is validated as the actual reducing agent.

[Chemical weapons and chemical terrorism].

Science.gov (United States)

Nakamura, Katsumi

2005-10-01

Chemical Weapons are kind of Weapons of Mass Destruction (WMD). They were used large quantities in WWI. Historically, large quantities usage like WWI was not recorded, but small usage has appeared now and then. Chemical weapons are so called "Nuclear weapon for poor countrys" because it's very easy to produce/possession being possible. They are categorized (1) Nerve Agents, (2) Blister Agents, (3) Cyanide (blood) Agents, (4) Pulmonary Agents, (5) Incapacitating Agents (6) Tear Agents from the viewpoint of human body interaction. In 1997 the Chemical Weapons Convention has taken effect. It prohibits chemical weapons development/production, and Organization for the Prohibition of Chemical Weapons (OPCW) verification regime contributes to the chemical weapons disposal. But possibility of possession/use of weapons of mass destruction by terrorist group represented in one by Matsumoto and Tokyo Subway Sarin Attack, So new chemical terrorism countermeasures are necessary.

Disposal of chemical agents and munitions stored at Pine Bluff Arsenal, Pine Bluff, Arkansas

Energy Technology Data Exchange (ETDEWEB)

Ensminger, J.T.; Hillsman, E.L.; Johnson, R.D.; Morrisey, J.A.; Staub, W.P.; Boston, C.R.; Hunsaker, D.B.; Leibsch, E.; Rickert, L.W.; Tolbert, V.R.; Zimmerman, G.P.

1991-09-01

The Pine Bluff Arsenal (PBA) near Pine Bluff, Arkansas, is one of eight continental United States (CONUS) Army installations where lethal unitary chemical agents and munitions are stored and where destruction of agents and munitions is proposed under the Chemical Stockpile Disposal Program (CSDP). The chemical agent inventory at PBA consists of approximately 12%, by weight, of the total US stockpile. The destruction of the stockpile is necessary to eliminate the risk to the public from continued storage and to dispose of obsolete and leaking munitions. In 1988 the US Army issued a Final Programmatic Environmental Impact Statement (FPEIS) for the CSDP that identified on-site disposal of agents and munitions as the environmentally preferred alternative (i.e., the alternative with the least potential to cause significant adverse impacts). The purpose of this report is to examine the proposed implementation of on-site disposal at PBA in light of more recent and more detailed data than those on which the FPEIS is based. New population data were used to compute fatalities using the same computation methods and values for all other parameters as in the FPEIS. Results indicate that all alternatives are indistinguishable when the potential health impacts to the PBA community are considered. However, risks from on-site disposal are in all cases equal to or less than risks from other alternatives. Furthermore, no unique resources with the potential to prevent or delay implementation of on-site disposal at PBA have been identified.

Chemical Warfare Agent Operational Exposure Hazard Assessment Research: FY07 Report and Analysis

Science.gov (United States)

2010-07-01

agent migration rates. As stated by Armour and Sturgeon (1992), the extent of the contact hazard depends on the initial degree of contamination, the...with a contaminated surface. 2.1.5 Literature Cited 1. Armour , S.J; Sturgeon, W.R. Liquid Hazard from Chemical Warfare Agents for Pilots of High...the neck area was clipped and prepped with betadine, and the animal covered with a sterile surgical drape . The planned incision areas in the

Odour as a determinant of persistent symptoms after a chemical explosion, a longitudinal study

OpenAIRE

Tjalvin, Gro; Magerøy, Nils; Bråtveit, Magne; Lygre, Stein Håkon Låstad; Hollund, Bjørg Eli; Moen, Bente Elisabeth

2017-01-01

Foul-smelling environmental pollution was a major concern following a chemical workplace explosion. Malodorous pollution has previously been associated with aggravated physical and psychological health, and in persons affected by a trauma, an incidence-related odour can act as a traumatic reminder. Olfaction may even be of significance in the development and persistence of post-traumatic stress symptoms (PTSS). The present longitudinal study assessed whether perceived smell related to malodor...

Dependence of radioprotective effect of chemical modifying agents on their intracellular concentrations

International Nuclear Information System (INIS)

Eidus, L.K.; Korystov, Y.N.; Kublik, L.N.; Vexler, A.M.

1982-01-01

Regularities of the radioprotective effect of chemical modifying agents cysteamine, caffeine benzoate, thioglycolic acid, and caffeine, all weak electrolytes, have been studied in cultured Chinese hamster cells. Efficiency of protection is shown to be dependent on pH and concentrations of the drug inside the cells and in the medium. Based on the theory of the dissociation of weak electrolytes and their distribution between the cells and the medium a strong correlation between the efficiency of modification of the radiation response and intracellular concentration of a modifying agent is shown. (author)

On modeling of the evaporation of chemical warfare agents on the ground

NARCIS (Netherlands)

Westin, S.N.; Winter, S.; Karlsson, E.; Hin, A.; Oeseburg, F.

1998-01-01

A model for evaporation of chemical warfare agents on the ground has been developed. The process of evaporation is described in three steps: (1) the immediate drop enlargement due to impact momentum is modeled using an empirical correlation from technical literature; (2) further enlargement caused

MOFwich: Sandwiched Metal-Organic Framework-Containing Mixed Matrix Composites for Chemical Warfare Agent Removal.

Science.gov (United States)

Peterson, Gregory W; Lu, Annie X; Hall, Morgan G; Browe, Matthew A; Tovar, Trenton; Epps, Thomas H

2018-02-28

This work describes a new strategy for fabricating mixed matrix composites containing layered metal-organic framework (MOF)/polymer films as functional barriers for chemical warfare agent protection. Through the use of mechanically robust polymers as the top and bottom encasing layers, a high-MOF-loading, high-performance-core layer can be sandwiched within. We term this multifunctional composite "MOFwich". We found that the use of elastomeric encasing layers enabled core layer reformation after breakage, an important feature for composites and membranes alike. The incorporation of MOFs into the core layer led to enhanced removal of chemical warfare agents while simultaneously promoting moisture vapor transport through the composite, showcasing the promise of these composites for protection applications.

The Scarlet Letter of Alkylation: A Mini Review of Selective Alkylating Agents

Science.gov (United States)

Oronsky, Bryan T; Reid, Tony; Knox, Susan J; Scicinski, Jan J

2012-01-01

If there were a stigma scale for chemotherapy, alkylating agents would be ranked at the top of the list. The chemical term alkylation is associated with nonselective toxicity, an association that dates back to the use of nitrogen mustards during World War I as chemical warfare agents. That this stigma persists and extends to compounds that, through selectivity, attempt to “tame” the indiscriminate destructive potential of alkylation is the subject of this review. Selective alkylation, as it is referred to herein, constitutes an extremely nascent and dynamic field in oncology. The pharmacodynamic response to this selective strategy depends on a delicate kinetic balance between specificity and the rate and extent of binding. Three representative compounds are presented: RRx-001, 3-bromopyruvate, and TH-302. The main impetus for the development of these compounds has been the avoidance of the serious complications of traditional alkylating agents; therefore, it is the thesis of this review that they should not experience stigma by association. PMID:22937173

The scarlet letter of alkylation: a mini review of selective alkylating agents.

Science.gov (United States)

Oronsky, Bryan T; Reid, Tony; Knox, Susan J; Scicinski, Jan J

2012-08-01

If there were a stigma scale for chemotherapy, alkylating agents would be ranked at the top of the list. The chemical term alkylation is associated with nonselective toxicity, an association that dates back to the use of nitrogen mustards during World War I as chemical warfare agents. That this stigma persists and extends to compounds that, through selectivity, attempt to "tame" the indiscriminate destructive potential of alkylation is the subject of this review. Selective alkylation, as it is referred to herein, constitutes an extremely nascent and dynamic field in oncology. The pharmacodynamic response to this selective strategy depends on a delicate kinetic balance between specificity and the rate and extent of binding. Three representative compounds are presented: RRx-001, 3-bromopyruvate, and TH-302. The main impetus for the development of these compounds has been the avoidance of the serious complications of traditional alkylating agents; therefore, it is the thesis of this review that they should not experience stigma by association.

Mass spectrometric study of selected precursors and degradation products of chemical warfare agents

Czech Academy of Sciences Publication Activity Database

Papoušková, B.; Bednář, P.; Fryšová, I.; Stýskala, J.; Hlaváč, J.; Barták, P.; Ulrichová, J.; Jirkovský, Jaromír; Lemr, K.

2007-01-01

Roč. 42, č. 12 (2007), s. 1550-1561 ISSN 1076-5174 Grant - others:The Organization for the Prohibition of Chemical Weapons (NL) L/ICA/ICB/84322/04 Institutional research plan: CEZ:AV0Z40400503 Source of funding: V - iné verejné zdroje Keywords : mass spectrometry * chemical warfare agent * high performance liquid chromatography * LC/MS Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.062, year: 2007

Multifunctional ultra-high vacuum apparatus for studies of the interactions of chemical warfare agents on complex surfaces

International Nuclear Information System (INIS)

Wilmsmeyer, Amanda R.; Morris, John R.; Gordon, Wesley O.; Mantooth, Brent A.; Lalain, Teri A.; Davis, Erin Durke

2014-01-01

A fundamental understanding of the surface chemistry of chemical warfare agents is needed to fully predict the interaction of these toxic molecules with militarily relevant materials, catalysts, and environmental surfaces. For example, rules for predicting the surface chemistry of agents can be applied to the creation of next generation decontaminants, reactive coatings, and protective materials for the warfighter. Here, we describe a multifunctional ultra-high vacuum instrument for conducting comprehensive studies of the adsorption, desorption, and surface chemistry of chemical warfare agents on model and militarily relevant surfaces. The system applies reflection-absorption infrared spectroscopy, x-ray photoelectron spectroscopy, and mass spectrometry to study adsorption and surface reactions of chemical warfare agents. Several novel components have been developed to address the unique safety and sample exposure challenges that accompany the research of these toxic, often very low vapor pressure, compounds. While results of vacuum-based surface science techniques may not necessarily translate directly to environmental processes, learning about the fundamental chemistry will begin to inform scientists about the critical aspects that impact real-world applications

Multifunctional ultra-high vacuum apparatus for studies of the interactions of chemical warfare agents on complex surfaces.

Science.gov (United States)

Wilmsmeyer, Amanda R; Gordon, Wesley O; Davis, Erin Durke; Mantooth, Brent A; Lalain, Teri A; Morris, John R

2014-01-01

A fundamental understanding of the surface chemistry of chemical warfare agents is needed to fully predict the interaction of these toxic molecules with militarily relevant materials, catalysts, and environmental surfaces. For example, rules for predicting the surface chemistry of agents can be applied to the creation of next generation decontaminants, reactive coatings, and protective materials for the warfighter. Here, we describe a multifunctional ultra-high vacuum instrument for conducting comprehensive studies of the adsorption, desorption, and surface chemistry of chemical warfare agents on model and militarily relevant surfaces. The system applies reflection-absorption infrared spectroscopy, x-ray photoelectron spectroscopy, and mass spectrometry to study adsorption and surface reactions of chemical warfare agents. Several novel components have been developed to address the unique safety and sample exposure challenges that accompany the research of these toxic, often very low vapor pressure, compounds. While results of vacuum-based surface science techniques may not necessarily translate directly to environmental processes, learning about the fundamental chemistry will begin to inform scientists about the critical aspects that impact real-world applications.

Multifunctional ultra-high vacuum apparatus for studies of the interactions of chemical warfare agents on complex surfaces

Energy Technology Data Exchange (ETDEWEB)

Wilmsmeyer, Amanda R.; Morris, John R. [Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24061 (United States); Gordon, Wesley O.; Mantooth, Brent A.; Lalain, Teri A. [Research and Technology Directorate, U.S. Army Edgewood Chemical Biological Center, Aberdeen Proving Ground, Maryland 21010 (United States); Davis, Erin Durke [OptiMetrics, Inc., Abingdon, Maryland 21009 (United States)

2014-01-15

A fundamental understanding of the surface chemistry of chemical warfare agents is needed to fully predict the interaction of these toxic molecules with militarily relevant materials, catalysts, and environmental surfaces. For example, rules for predicting the surface chemistry of agents can be applied to the creation of next generation decontaminants, reactive coatings, and protective materials for the warfighter. Here, we describe a multifunctional ultra-high vacuum instrument for conducting comprehensive studies of the adsorption, desorption, and surface chemistry of chemical warfare agents on model and militarily relevant surfaces. The system applies reflection-absorption infrared spectroscopy, x-ray photoelectron spectroscopy, and mass spectrometry to study adsorption and surface reactions of chemical warfare agents. Several novel components have been developed to address the unique safety and sample exposure challenges that accompany the research of these toxic, often very low vapor pressure, compounds. While results of vacuum-based surface science techniques may not necessarily translate directly to environmental processes, learning about the fundamental chemistry will begin to inform scientists about the critical aspects that impact real-world applications.

Katharsis of the skin: Peeling applications and agents of chemical peelings in Greek medical textbooks of Graeco-Roman antiquity.

Science.gov (United States)

Ursin, F; Steger, F; Borelli, C

2018-04-28

Recipes for peelings date back to medical texts of old Egypt. The oldest medical papyri contain recipes for "improving beauty of the skin" and "removing wrinkles" by use of agents like salt and soda. The Egyptian Queen Cleopatra (69-30 BC) is said to have taken bathes in donkey's milk in order to improve the beauty of her skin. However, little is known about other agents and peeling applications in later Greek medical textbooks. We will discover new agents and describe ancient peeling applications. First, we will have to identify ancient Greek medical terms for the modern terms "peeling" and "chemical peeling". Second, based on the identified terms we will perform a systematic fulltext search for agents in original sources. Third, we will categorize the results into three peeling applications: (1) cleansing, (2) aesthetical improvement of the skin, and (3) therapy of dermatological diseases. We performed a full systematic keyword search with the identified Greek terms in databases of ancient Greek texts. Our keywords for peeling and chemical peeling are "smēxis" and "trīpsis". Our keywords for agents of peeling and chemical peeling are "smégmata", "rhýmmata", "kathartiká", and "trímmata". Diocles (4 th century BC) was the first one who mentioned "smēxis" and "trīpsis" as parts of daily cleansing routine. Criton (2 nd century AD) wrote about peeling applications, but any reference to the agents is lost. Antyllos (2 nd century AD) composed three lists of peeling applications including agents. Greek medical textbooks of Graeco-Roman antiquity report several peeling applications like cleansing, brightening, darkening, softening, and aesthetical improvement of the skin by use of peeling and chemical peeling, as well as therapy of dermatological diseases. There are 27 ancient agents for what is contemporarily called peeling and chemical peeling. We discovered more specific agents than hitherto known to research. This article is protected by copyright. All rights

Destruction of chlorine-containing organic agents in a system plasma - liquid

International Nuclear Information System (INIS)

Chernyak, V.Ya.; Yukhymenko, V.V.; Babich, I.L.; Slyusarenko, Y.I.; Tarasova, Ya.B.

2005-01-01

The plasma chemical destruction of persistent toxic agent 1,1-di(4-chlorophenol)-2,2,2-threechlorethane (DDT) in water solutions is researched in this work. The destruction of agricultural pesticide containing DDT was carried out in water solution at atmospheric pressure with usage of plasma treatment on the basis of secondary discharges with a 'liquid' electrode, and of combination of a plasma method with reagent method. The comparative analysis of results of the physical-chemical analysis and biological test of toxicity of solutions is carried out and the optimum regimes for destruction and detoxication of DDT in water are determined

Detection and identification of alkylating agents by using a bioinspired "chemical nose".

Science.gov (United States)

Hertzog-Ronen, Carmit; Borzin, Elena; Gerchikov, Yulia; Tessler, Nir; Eichen, Yoav

2009-10-12

Alkylating agents are simple and reactive molecules that are commonly used in many and diverse fields such as organic synthesis, medicine, and agriculture. Some highly reactive alkylating species are also being used as blister chemical-warfare agents. The detection and identification of alkylating agents is not a trivial issue because of their high reactivity and simple structure. Herein, we report on a new multispot luminescence-based approach to the detection and identification of alkylating agents. In order to demonstrate the potential of the approach, seven pi-conjugated oligomers and polymers bearing nucleophilic pyridine groups, 1-7, were adsorbed onto a solid support and exposed to vapors of alkylators 8-15. The alkylation-induced color-shift patterns of the seven-spot array allow clear discrimination of the different alkylators. The spots are sensitive to minute concentrations of alkylators and, because the detection is based on the formation of new covalent bonds, these spots saturate at about 50 ppb.

Disposal of chemical agents and munitions stored at Umatilla Depot Activity, Hermiston, Oregon

Energy Technology Data Exchange (ETDEWEB)

Zimmerman, G.P.; Hillsman, E.L.; Johnson, R.O.; Miller, R.L.; Patton, T.G.; Schoepfle, G.M.; Tolbert, V.R.; Feldman, D.L.; Hunsaker, D.B. Jr.; Kroodsma, R.L.; Morrissey, J.; Rickert, L.W.; Staub, W.P.; West, D.C.

1993-02-01

The Umatilla Depot Activity (UMDA) near Hermiston, Oregon, is one of eight US Army installations in the continental United States where lethal unitary chemical agents and munitions are stored, and where destruction of agents and munitions is proposed under the Chemical Stockpile Disposal Program (CSDP). The chemical agent inventory at UMDA consists of 11.6%, by weight, of the total US stockpile. The destruction of the stockpile is necessary to eliminate the risk to the public from continued storage and to dispose of obsolete and leaking munitions. In 1988 the US Army issued a Final Programmatic Environmental Impact Statement (FPEIS) for the CSDP that identified on-site disposal of agents and munitions as the environmentally preferred alternative (i.e., the alternative with the least potential to cause significant adverse impacts), using a method based on five measures of risk for potential human health and ecosystem/environmental effects; the effectiveness and adequacy of emergency preparedness capabilities also played a key role in the FPEIS selection methodology. In some instances, the FPEIS included generic data and assumptions that were developed to allow a consistent comparison of potential impacts among programmatic alternatives and did not include detailed conditions at each of the eight installations. The purpose of this Phase 1 report is to examine the proposed implementation of on-site disposal at UMDA in light of more recent and more detailed data than those included in the FPEIS. Specifically, this Phase 1 report is intended to either confirm or reject the validity of on-site disposal for the UMDA stockpile. Using the same computation methods as in the FPEIS, new population data were used to compute potential fatalities from hypothetical disposal accidents. Results indicate that onsite disposal is clearly preferable to either continued storage at UMDA or transportation of the UMDA stockpile to another depot for disposal.

Diagnosis of Exposure to Chemical Warfare Agents: A Comprehensive Literature Survey 1990-2005

National Research Council Canada - National Science Library

Noort, D

2006-01-01

This report is an update of TNO report PML 2003-A63. In this report an overview is presented of the methods currently available for detection of exposure to a number of chemical warfare agents (CWA), i.e...

Next Generation Non-particulate Dry Nonwoven Pad for Chemical Warfare Agent Decontamination

Energy Technology Data Exchange (ETDEWEB)

Ramkumar, S S; Love, A; Sata, U R; Koester, C J; Smith, W J; Keating, G A; Hobbs, L; Cox, S B; Lagna, W M; Kendall, R J

2008-05-01

New, non-particulate decontamination materials promise to reduce both military and civilian casualties by enabling individuals to decontaminate themselves and their equipment within minutes of exposure to chemical warfare agents or other toxic materials. One of the most promising new materials has been developed using a needlepunching nonwoven process to construct a novel and non-particulate composite fabric of multiple layers, including an inner layer of activated carbon fabric, which is well-suited for the decontamination of both personnel and equipment. This paper describes the development of a composite nonwoven pad and compares efficacy test results for this pad with results from testing other decontamination systems. The efficacy of the dry nonwoven fabric pad was demonstrated specifically for decontamination of the chemical warfare blister agent bis(2-chloroethyl)sulfide (H or sulfur mustard). GC/MS results indicate that the composite fabric was capable of significantly reducing the vapor hazard from mustard liquid absorbed into the nonwoven dry fabric pad. The mustard adsorption efficiency of the nonwoven pad was significantly higher than particulate activated carbon (p=0.041) and was similar to the currently fielded US military M291 kit (p=0.952). The nonwoven pad has several advantages over other materials, especially its non-particulate, yet flexible, construction. This composite fabric was also shown to be chemically compatible with potential toxic and hazardous liquids, which span a range of hydrophilic and hydrophobic chemicals, including a concentrated acid, an organic solvent and a mild oxidant, bleach.

Abundance, Genetic Diversity and Persistence of Metarhizium Spp. Fungi from Soil of Strawberry Crops and Their Potential as Biological Control Agents against the Two-Spotted Spider Mite Tetranychus urticae

DEFF Research Database (Denmark)

Castro, Thiago Rodriguesde

The growing demand for strawberries has imposed challenges, especially regarding the control of pests. Many farmers report problems with reduced chemical control efficiency, probably due to selection of resistant populations of insects and mites. An alternative is the use of biological control...... agent were performed, but this bulk of knowledge is in remarkable contrast to the lack of research on the fundamental ecology of Metarhizium in agroecosystems. This thesis aimed to evaluate the establishment, persistence and dispersal of these entomopathogenic fungi in strawberry crop soil...... in Inconfidentes, Minas Gerais, Brazil; and to study the diversity and abundance of species of Metarhizium isolated from organic and conventional strawberry crop soils, and from the field margins in Brazil and Denmark. The effectiveness of new species of Metarhizium recently found in Brazil, was evaluated against...

Analysis of the Precursors, Simulants and Degradation Products of Chemical Warfare Agents.

Science.gov (United States)

Witkiewicz, Zygfryd; Neffe, Slawomir; Sliwka, Ewa; Quagliano, Javier

2018-09-03

Recent advances in analysis of precursors, simulants and degradation products of chemical warfare agents (CWA) are reviewed. Fast and reliable analysis of precursors, simulants and CWA degradation products is extremely important at a time, when more and more terrorist groups and radical non-state organizations use or plan to use chemical weapons to achieve their own psychological, political and military goals. The review covers the open source literature analysis after the time, when the chemical weapons convention had come into force (1997). The authors stated that during last 15 years increased number of laboratories are focused not only on trace analysis of CWA (mostly nerve and blister agents) in environmental and biological samples, but the growing number of research are devoted to instrumental analysis of precursors and degradation products of these substances. The identification of low-level concentration of CWA degradation products is often more important and difficult than the original CWA, because of lower level of concentration and a very large number of compounds present in environmental and biological samples. Many of them are hydrolysis products and are present in samples in the ionic form. For this reason, two or three instrumental methods are used to perform a reliable analysis of these substances.

Feasibility Study for the Use of Green, Bio-Based, Efficient Reactive Sorbent Material to Neutralize Chemical Warfare Agents

Science.gov (United States)

2012-08-02

REPORT Feasibility study for the use of green, bio-based, efficient reactive sorbent material to neutralize chemical warfare agents 14. ABSTRACT 16...way cellulose, lignin and hemicelluloses interact as well as whole wood dissolution occurs in ILs. The present project was conducted to 1. REPORT...Feasibility study for the use of green, bio-based, efficient reactive sorbent material to neutralize chemical warfare agents Report Title ABSTRACT Over the

Test Results of Level A Suits to Challenge by Chemical and Biological Warfare Agents and Simulants: Summary Report

National Research Council Canada - National Science Library

Belmonte, Richard B

1998-01-01

...) terrorism incidents. As part of an effective response, people who are responding to an incident will use personal protective equipment to protect them from exposure to chemical agents or biological agents...

Immunohistopathology in the Guinea Pig Following Chronic Low-Level Exposure to Chemical Warfare Agents

Science.gov (United States)

2005-11-01

U.S. Army Medical Research Institute of Chemical Defense USAMRICD-TR-05-09 Immunohistopathology in the Guinea Pig Following Chronic Low...2005 2. REPORT TYPE Technical Report 3. DATES COVERED (From - To) May 2003 to April 2005 4. TITLE AND SUBTITLE Immunohistopathology in the Guinea Pig Following...release; distribution unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Guinea pigs exposed repeatedly to low levels of chemical warfare nerve agents

Cooperative biological effects between ionizing radiation and other physical and chemical agents.

Science.gov (United States)

Manti, Lorenzo; D'Arco, Annalisa

2010-01-01

Exposure to ionizing radiation (IR), at environmentally and therapeutically relevant doses or as a result of diagnostics or accidents, causes cyto- and genotoxic damage. However, exposure to IR alone is a rare event as it occurs in spatial and temporal combination with several physico-chemical agents. Some of these are of known noxiousness, as is the case with chemical compounds at high dose, hence additive/synergistic effects can be expected or have been demonstrated. Conversely, the cellular toxicity of other agents, such as non-ionizing electromagnetic fields (EMFs), is only presumed and their short- and long-term cooperation on IR-induced damage remains undetermined. In this review, we shall examine evidence in support of the interplay between spatially and/or temporally related environmentally relevant stressors. In vitro or animal-based studies as well as epidemiological surveys have generally examined the combined action of no more than a couple of known or potentially DNA-damaging agents. Moreover, most existing research mainly focused on short-term effects of combined exposures. Hence, it is important that quantitative research addresses the issue of the possible cooperation between chronic exposure to environmental trace contaminants and exposure to EMFs, examining not only the modulation of damage acutely induced by IR but also long-term genome stability. 2010 Elsevier B.V. All rights reserved.

Comparison of Selected Methods for Individual Decontamination of Chemical Warfare Agents

OpenAIRE

Tomas Capoun; Jana Krykorkova

2014-01-01

This study addresses the individual decontamination of chemical warfare agents (CWA) and other hazardous substances. The individual decontamination applies to contaminated body surfaces, protective clothing and objects immediately after contamination, performed individually or by mutual assistance using prescribed or improvised devices. The article evaluates the importance of individual decontamination, security level for Fire and Rescue Service Units of the Czech Republic (FRS CR) and demons...

Effects of chemical and biological warfare remediation agents on the materials of museum objects

Science.gov (United States)

Solazzo, C.; Erhardt, D.; Marte, F.; von Endt, D.; Tumosa, C.

In the fall of 2001, anthrax-contaminated letters were sent to public figures in the United States. Chemical and radiation treatments were employed to decontaminate exposed buildings, objects, and materials. These treatments are effective, but potentially damaging to exposed objects and materials. The recommended surface chemical treatments include solutions, gels, and foams of oxidizing agents such as peroxides or chlorine bleaching agents. Such oxidizing agents are effective against a wide range of hazardous chemical and biological agents. Knowing how these reagents affect various substrates would help to anticipate and to minimize any potential damage. We are examining the effects on typical museum materials of reagents likely to be used, including hydrogen peroxide, sodium hypochlorite, and potassium peroxymonosulfate. Results so far show significant changes in a number of materials. Surface corrosion was observed on metals such as copper, silver, iron, and brass. Color changes occurred with at least one reagent in about one-fourth of the dyed fabric swatches tested, and about half of the inks. Samples of aged yellowed paper are bleached. Effects varied with both the substrate and the tested reagent. The observed changes were generally less drastic than might have been expected. Enough materials were affected, though, to preclude the use of these reagents on museum objects unless no less drastic alternative is available. It appears that many objects of lesser intrinsic value can be treated without severe loss of properties or usefulness. For example, most documents should remain legible if the appropriate reagent is used. This work will provide a basis for determining which treatment is most appropriate for a specific situation and what consequences are to be expected from other treatments.

Toxicity induced by chemical warfare agents: insights on the protective role of melatonin.

Science.gov (United States)

Pita, René; Marco-Contelles, José; Ramos, Eva; Del Pino, Javier; Romero, Alejandro

2013-11-25

Chemical Warfare Agents (CWAs) are substances that can be used to kill, injure or incapacitate an enemy in warfare, but also against civilian population in terrorist attacks. Many chemical agents are able to generate free radicals and derived reactants, excitotoxicity process, or inflammation, and as consequence they can cause neurological symptoms and damage in different organs. Nowadays, taking into account that total immediate decontamination after exposure is difficult to achieve and there are not completely effective antidotes and treatments against all CWAs, we advance and propose that medical countermeasures against CWAs poisoning would benefit from a broad-spectrum multipotent molecule. Melatonin, a versatile and ubiquitous antioxidant molecule, originally discovered as a hormone synthesized mainly in the pineal gland, has low toxicity and high efficacy in reducing oxidative damage, anti-inflammatory effects by regulation of multiple cellular pathways and properties to prevent excitotoxicity, among others. The purpose of this review is to show the multiple and diverse properties of melatonin, as a pleiotropic indole derivative, and its marked potential for improving human health against the most widely used chemical weapons. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Persistence of Coxiella burnetii, the agent of Q fever, in murine adipose tissue.

Directory of Open Access Journals (Sweden)

Yassina Bechah

Full Text Available Coxiella burnetii, the agent of Q fever, is known to persist in humans and rodents but its cellular reservoir in hosts remains undetermined. We hypothesized that adipose tissue serves as a C. burnetii reservoir during bacterial latency. BALB/c and C57BL/6 mice were infected with C. burnetii by the intraperitoneal route or the intracheal route. Adipose tissue was tested for the presence of C. burnetii several months after infection. C. burnetii was detected in abdominal, inguinal and dorsal adipose tissue 4 months post-infection, when no bacteria were detected in blood, liver, lungs and spleen, regardless of the inoculation route and independently of mouse strain. The transfer of abdominal adipose tissue from convalescent BALB/c mice to naïve immunodeficient mice resulted in the infection of the recipient animals. It is likely that C. burnetii infects adipocytes in vivo because bacteria were found in adipocytes within adipose tissue and replicated within in vitro-differentiated adipocytes. In addition, C. burnetii induced a specific transcriptional program in in-vivo and in vitro-differentiated adipocytes, which was enriched in categories associated with inflammatory response, hormone response and cytoskeleton. These changes may account for bacterial replication in in-vitro and chronic infection in-vivo. Adipose tissue may be the reservoir in which C. burnetii persists for prolonged periods after apparent clinical cure. The mouse model of C. burnetii infection may be used to understand the relapses of Q fever and provide new perspectives to the follow-up of patients.

Root Canal Irrigation: Chemical Agents and Plant Extracts Against Enterococcus faecalis

Science.gov (United States)

Borzini, Letizia; Condò, Roberta; De Dominicis, Paolo; Casaglia, Adriano; Cerroni, Loredana

2016-01-01

Background: There are various microorganisms related to intra and extra-radicular infections and many of these are involved in persistent infections. Bacterial elimination from the root canal is achieved by means of the mechanical action of instruments and irrigation as well as the antibacterial effects of the irrigating solutions. Enterococcus faecalis can frequently be isolated from root canals in cases of failed root canal treatments. Antimicrobial agents have often been developed and optimized for their activity against endodontic bacteria. An ideal root canal irrigant should be biocompatible, because of its close contact with the periodontal tissues during endodontic treatment. Sodium hypoclorite (NaOCl) is one of the most widely recommended and used endodontic irrigants but it is highly toxic to periapical tissues. Objectives: To analyze the literature on the chemotherapeutic agent and plant extracts studied as root canal irrigants. In particularly, the study is focused on their effect on Enterococcus faecalis. Method: Literature search was performed electronically in PubMed (PubMed Central, MEDLINE) for articles published in English from 1982 to April 2015. The searched keywords were “endodontic irrigants” and “Enterococcus faecalis” and “essential oil” and “plant extracts”. Results: Many of the studied chemotherapeutic agents and plant extracts have shown promising results in vitro. Conclusion: Some of the considered phytotherapic substances, could be a potential alternative to NaOCl for the biomechanical treatment of the endodontic space. PMID:28217184

Modern sample preparation techniques for gas chromatography-mass spectrometry analysis of environmental markers of chemical warfare agents use

NARCIS (Netherlands)

Terzic, O.; de Voogt, P.; Banoub, J.

2014-01-01

The chapter introduces problematics of on-site chemical analysis in the investigations of past chemical warfare agents (CWA) events. An overview of primary environmental degradation pathways of CWA leading to formation of chemical markers of their use is given. Conventional and modern sample

Chemical warfare agent simulants for human volunteer trials of emergency decontamination: A systematic review.

Science.gov (United States)

James, Thomas; Wyke, Stacey; Marczylo, Tim; Collins, Samuel; Gaulton, Tom; Foxall, Kerry; Amlôt, Richard; Duarte-Davidson, Raquel

2018-01-01

Incidents involving the release of chemical agents can pose significant risks to public health. In such an event, emergency decontamination of affected casualties may need to be undertaken to reduce injury and possible loss of life. To ensure these methods are effective, human volunteer trials (HVTs) of decontamination protocols, using simulant contaminants, have been conducted. Simulants must be used to mimic the physicochemical properties of more harmful chemicals, while remaining non-toxic at the dose applied. This review focuses on studies that employed chemical warfare agent simulants in decontamination contexts, to identify those simulants most suitable for use in HVTs of emergency decontamination. Twenty-two simulants were identified, of which 17 were determined unsuitable for use in HVTs. The remaining simulants (n = 5) were further scrutinized for potential suitability according to toxicity, physicochemical properties and similarities to their equivalent toxic counterparts. Three suitable simulants, for use in HVTs were identified; methyl salicylate (simulant for sulphur mustard), diethyl malonate (simulant for soman) and malathion (simulant for VX or toxic industrial chemicals). All have been safely used in previous HVTs, and have a range of physicochemical properties that would allow useful inference to more toxic chemicals when employed in future studies of emergency decontamination systems. © 2017 Crown Copyright. Journal of Applied Toxicology published by John Wiley & Sons, Ltd.

Cerium oxide for the destruction of chemical warfare agents: A comparison of synthetic routes

Czech Academy of Sciences Publication Activity Database

Janos, P.; Henych, Jiří; Pelant, O.; Pilařová, V.; Vrtoch, L.; Kormunda, M.; Mazanec, K.; Štengl, Václav

2016-01-01

Roč. 304, MAR (2016), s. 259-268 ISSN 0304-3894 Institutional support: RVO:61388980 Keywords : Cerium oxide * Chemical warfare agents * Organophosphate compounds * Decontamination Subject RIV: CA - Inorganic Chemistry Impact factor: 6.065, year: 2016

Chemical warfare agent simulants for human volunteer trials of emergency decontamination: A systematic review

OpenAIRE

James, Thomas; Wyke, Stacey; Marczylo, Tim; Collins, Samuel; Gaulton, Tom; Foxall, Kerry; Amlôt, Richard; Duarte‐Davidson, Raquel

2017-01-01

Abstract Incidents involving the release of chemical agents can pose significant risks to public health. In such an event, emergency decontamination of affected casualties may need to be undertaken to reduce injury and possible loss of life. To ensure these methods are effective, human volunteer trials (HVTs) of decontamination protocols, using simulant contaminants, have been conducted. Simulants must be used to mimic the physicochemical properties of more harmful chemicals, while remaining ...

Cohesive Motion Control Algorithm for Formation of Multiple Autonomous Agents

Directory of Open Access Journals (Sweden)

Debabrata Atta

2010-01-01

Full Text Available This paper presents a motion control strategy for a rigid and constraint consistent formation that can be modeled by a directed graph whose each vertex represents individual agent kinematics and each of directed edges represents distance constraints maintained by an agent, called follower, to its neighbouring agent. A rigid and constraint consistent graph is called persistent graph. A persistent graph is minimally persistent if it is persistent, and no edge can be removed without losing its persistence. An acyclic (free of cycles in its sensing pattern minimally persistent graph of Leader-Follower structure has been considered here which can be constructed from an initial Leader-Follower seed (initial graph with two vertices, one is Leader and another one is First Follower and one edge in between them is directed towards Leader by Henneberg sequence (a procedure of growing a graph containing only vertex additions. A set of nonlinear optimization-based decentralized control laws for mobile autonomous point agents in two dimensional plane have been proposed. An infinitesimal deviation in formation shape created continuous motion of Leader is compensated by corresponding continuous motion of other agents fulfilling the shortest path criteria.

Chemical nickel plating in tartrate solutions with borohydride reducing agent

International Nuclear Information System (INIS)

Plokhov, V.A.

1986-01-01

The authors investigate the influence of various factors on the rate of chemical nickel plating in strongly alkaline tartrate solutions with a borohydride reducing agent. After 30 min of the process of nickel plating, the final concentration of sodium borohydride decreases to 0.26 g/liter, leading to stoppage of the process. The nickel plating process can be intensified by increasing the concentration of sodium hydroxide in the solution, suppressing hydrolysis of borohydride, and also by introducing additives which suppress hydrolysis of borohydride. For chemical deposition of nickel-boron coatings from tartrate solutions the authors recommend the following composition (g/liter): nickel chloride 15-25, Rochelle salt 450-550, sodium hydroxide 140-160, sodium borohydride 0.8-1.0, thallium nitrate 0.003-0.008. The process temperature is 92-95 C, and the deposition rate is 4-6 um/h

Environmental toxicity of Chemical Warfare Agents (CWAs) - MicrotoxTM and Spontaneous Locomotor Changes

DEFF Research Database (Denmark)

Storgaard, Morten Swayne; Sanderson, Hans; Baatrup, Erik

After the 2nd World War the CWAs were prohibited by law and 11,000 tonnes of toxic agents were dumped in the Bornholm Basin east of Bornholm. The dumped chemical munitions have not reached attention from politicians and scientists until recently. During earlier projects, such as MERCW (2005...

Investigation of Acute Toxicity of a Chemical Warfare Agent in Kidneys

Directory of Open Access Journals (Sweden)

Turgut Topal

2007-08-01

Full Text Available One of the most important chemical warfare agents, sulfur mustard (SM causes crucial acute and chronic toxic effects. Lung, skin, eye and kidneys are the most affected organs. In this work, it was investigated if increased nitric oxide (NO and peroxynitrite are involved in nitrogen mustard (NM induced kidney damage. In this experimen, aminoguanidine (AG as inducible nitric oxide synthase (iNOS inhibitor and ebselen as peroxynitrite scavenger were used. NM administration resulted in important oxidant and antioxidant changes as well as tissue damage in kidneys. Therapeutic agents showed significant protection and reduced oxidant parameteres leading to tissue healing was observed. Results of this study suggest that drugs with similar properties can be used to protect kidney damage caused by NM. [TAF Prev Med Bull. 2007; 6(4: 227-232

Investigation of Acute Toxicity of a Chemical Warfare Agent in Kidneys

Directory of Open Access Journals (Sweden)

Turgut Topal

2007-08-01

Full Text Available One of the most important chemical warfare agents, sulfur mustard (SM causes crucial acute and chronic toxic effects. Lung, skin, eye and kidneys are the most affected organs. In this work, it was investigated if increased nitric oxide (NO and peroxynitrite are involved in nitrogen mustard (NM induced kidney damage. In this experimen, aminoguanidine (AG as inducible nitric oxide synthase (iNOS inhibitor and ebselen as peroxynitrite scavenger were used. NM administration resulted in important oxidant and antioxidant changes as well as tissue damage in kidneys. Therapeutic agents showed significant protection and reduced oxidant parameteres leading to tissue healing was observed. Results of this study suggest that drugs with similar properties can be used to protect kidney damage caused by NM. [TAF Prev Med Bull 2007; 6(4.000: 227-232

Occupation, exposure to chemicals, sensitizing agents, and risk of multiple myeloma in Sweden.

Science.gov (United States)

Lope, Virginia; Pérez-Gómez, Beatriz; Aragonés, Nuria; López-Abente, Gonzalo; Gustavsson, Per; Plato, Nils; Zock, Jan-Paul; Pollán, Marina

2008-11-01

This study sought to identify occupations with high incidence of multiple myeloma and to investigate possible excess risk associated with occupational exposure to chemicals and sensitizing agents in Sweden. A historical cohort of 2,992,166 workers was followed up (1971--1989) through record linkage with the National Cancer and Death Registries. For each job category, age and period standardized incidence ratios and age and period adjusted relative risks of multiple myeloma were calculated using Poisson models. Exposure to chemicals and to sensitizing agents was also assessed using two job-exposure matrices. Men and women were analyzed separately. During follow-up, 3,127 and 1,282 myelomas were diagnosed in men and women, respectively. In men, excess risk was detected among working proprietors, agricultural, horticultural and forestry enterprisers, bakers and pastry cooks, dental technicians, stone cutters/carvers, and prison/reformatory officials. In women, this excess was observed among attendants in psychiatric care, metal workers, bakers and pastry cooks, and paper/paperboard product workers. Workers, particularly bakers and pastry cooks, exposed to high molecular weight sensitizing agents registered an excess risk of over 40% across the sexes. Occasional, although intense, exposure to pesticides was also associated with risk of myeloma in our cohort. Our study supports a possible etiologic role for farming and use of pesticides in myeloma risk. The high incidence found in both female and male bakers and pastry cooks has not been described previously. Further research is required to assess the influence of high molecular weight sensitizing agents on risk of multiple myeloma.

Estimated general population control limits for unitary agents in drinking water, milk, soil, and unprocessed food items

Energy Technology Data Exchange (ETDEWEB)

Watson, A.P.; Adams, J.D.; Cerar, R.J.; Hess, T.L.; Kistner, S.L.; Leffingwell, S.S.; MacIntosh, R.G.; Ward, J.R.

1992-01-01

In the event of an unplanned release of chemical agent during any stage of the Chemical Stockpile Disposal Program (CSDP), the potential exists for contamination of drinking water, forage crops, grains, garden produce, and livestock. Persistent agents such as VX or sulfur mustard pose the greatest human health concern for reentry. This White Paper has been prepared to provide technical bases for these decisions by developing working estimates of agent control limits in selected environmental media considered principal sources of potential human exposure. To date, control limits for public exposure to unitary agents have been established for atmospheric concentrations only. The current analysis builds on previous work to calculate working estimates of control limits for ingestion and dermal exposure to potentially contaminated drinking water, milk, soil, and unprocessed food items such as garden produce. Information characterizing agent desorption from, and detection on or in, contaminated porous media are presently too developed to permit reasonable estimation of dermal exposure from this source. Thus, dermal contact with potentially contaminated porous surfaces is not considered in this document.

From the Decomposition of Chemical Warfare Agents to the Decontamination of Cytostatics

Czech Academy of Sciences Publication Activity Database

Štengl, Václav; Šťastný, Martin; Janoš, P.; Mazanec, K.; Perez-Diaz, J. L.; Štenglová Netíková, I. R.

2018-01-01

Roč. 57, č. 6 (2018), s. 2114-2122 ISSN 0888-5885 EU Projects: European Commission(XE) 312804 - COUNTERFOG Grant - others:NATO(US) SPS984599 Program:Science for Peace and Security Institutional support: RVO:61388980 Keywords : Chemical warfare agents * Degradation * Metal oxide sorbents Subject RIV: CA - Inorganic Chemistry OBOR OECD: Inorganic and nuclear chemistry Impact factor: 2.843, year: 2016

Polypropylene Track Membranes for Mikro and Ultrafiltration of Chemically Aggressive Agents

CERN Document Server

Kravets, L I; Apel, P Yu

2000-01-01

A production process for track membranes on the basis of chemically resistant polymer polypropylene has been developed. Research in all stages of the formation of the polypropylene track membranes has been conducted: the main principles of the process of chemical etching of polypropylene irradiated with accelerated ions have been investigated, the most effective structure of the etchant for a selective etching of the heavy ion tracks has been selected, the parameters of etching have been optimized. A method for sensibilization of latent tracks in polypropylene by effect of solvents has been developed. It helps to reach a significant increase in etching selectivity. A method for destruction of an absorbed chromocontaining layer on the surface of polypropylene track membranes formed during etching has been elaborated. Experimental samples of the membranes for micro and ultrafiltration have been obtained and their properties have been studied in course of their exploitation in chemically aggressive agents. For t...

Determination of trace amounts of chemical warfare agent degradation products in decontamination solutions with NMR spectroscopy.

Science.gov (United States)

Koskela, Harri; Rapinoja, Marja-Leena; Kuitunen, Marja-Leena; Vanninen, Paula

2007-12-01

Decontamination solutions are used for an efficient detoxification of chemical warfare agents (CWAs). As these solutions can be composed of strong alkaline chemicals with hydrolyzing and oxidizing properties, the analysis of CWA degradation products in trace levels from these solutions imposes a challenge for any analytical technique. Here, we present results of application of nuclear magnetic resonance spectroscopy for analysis of trace amounts of CWA degradation products in several untreated decontamination solutions. Degradation products of the nerve agents sarin, soman, and VX were selectively monitored with substantially reduced interference of background signals by 1D 1H-31P heteronuclear single quantum coherence (HSQC) spectrometry. The detection limit of the chemicals was at the low part-per-million level (2-10 microg/mL) in all studied solutions. In addition, the concentration of the degradation products was obtained with sufficient confidence with external standards.

Overview of shoreline cleaning agents

International Nuclear Information System (INIS)

Clayton, J.

1992-01-01

Chemical cleaning agents may be used to promote release of stranded oil from shorelines for reasons including biological sensitivity of indigenous fauna and flora to the oil, amenity considerations of the shoreline, or concern about refloating of the oil and subsequent stranding on adjacent shorelines. While use of chemical cleaning agents may be appropriate under proper toxic responses in circumstances, certain limitations should be recognized. The potential for toxic responses in indigenous fauna and flora to the cleaning agents must be considered. Enhanced penetration of oil into permeable shorelines following treatment with chemical cleaning agents also is not desirable. However, if conditions related to toxicity and substrate permeability are determined to be acceptable, the use of chemical cleaning agents for treatment of stranded oil can be considered. Chemical agents for cleaning oiled shorelines can be grouped into three categories: (1) non-surfactant-based solvents, (2) chemical dispersants, and (3) formulations especially designed to release stranded oil from shoreline substrates (i.e., shoreline-cleaning-agents). Depending on the specific circumstances present on an oiled shoreline, it is generally desirable that chemical agents used for cleaning will release oil from shoreline substrate(s) to surface waters. Recovery of the oil can then be accomplished by mechanical procedures such as booming and skimming operations

[Decontamination of chemical warfare agents by photocatalysis].

Science.gov (United States)

Hirakawa, Tsutomu; Mera, Nobuaki; Sano, Taizo; Negishi, Nobuaki; Takeuchi, Koji

2009-01-01

Photocatalysis has been widely applied to solar-energy conversion and environmental purification. Photocatalyst, typically titanium dioxide (TiO(2)), produces active oxygen species under irradiation of ultraviolet light, and can decompose not only conventional pollutants but also different types of hazardous substances at mild conditions. We have recently started the study of photocatalytic decontamination of chemical warfare agents (CWAs) under collaboration with the National Research Institute of Police Science. This article reviews environmental applications of semiconductor photocatalysis, decontamination methods for CWAs, and previous photocatalytic studies applied to CWA degradation, together with some of our results obtained with CWAs and their simulant compounds. The data indicate that photocatalysis, which may not always give a striking power, certainly helps detoxification of such hazardous compounds. Unfortunately, there are not enough data obtained with real CWAs due to the difficulty in handling. We will add more scientific data using CWAs in the near future to develop useful decontamination systems that can reduce the damage caused by possible terrorism.

Mass Spectrometric Determination of Chemical Warfare Agents in Indoor Sample Media Typically Collected During Forensic Investigations

National Research Council Canada - National Science Library

D'Agostino, P. A; Hancock, J. R; Chenier, C. L

2005-01-01

.... DRDC Suffield, in collaboration with the Royal Canadian Mounted Police, identified a need for analytical methods for chemical warfare agent identification in media, including flooring, wall surfaces...

Recent Canadian experience in chemical warfare agent destruction: An overview. Suffield report No. 626

Energy Technology Data Exchange (ETDEWEB)

McAndless, J.M.

1995-12-31

This paper reviews a project in which stockpiles of aged mustard (bis-2-chloroethyl sulfide), lewisite (2-chlorovinyl-dichloro arsine), nerve agents, and contaminated scrap metal were incinerated or chemically neutralized in a safe, environmentally responsible manner. Sections of the paper describe the public consultation program conducted prior to destruction operations, the environmental assessment of the destruction projects, the environmental protection plan implemented to eliminate or mitigate risks with respect to the installation and operation of the destruction equipment, the environmental monitoring procedures, the agent destruction operations, and the destruction process performance, including incinerator emissions.

Advances in toxicology and medical treatment of chemical warfare nerve agents

Science.gov (United States)

2012-01-01

Organophosphorous (OP) Nerve agents (NAs) are known as the deadliest chemical warfare agents. They are divided into two classes of G and V agents. Most of them are liquid at room temperature. NAs chemical structures and mechanisms of actions are similar to OP pesticides, but their toxicities are higher than these compounds. The main mechanism of action is irreversible inhibition of Acetyl Choline Esterase (AChE) resulting in accumulation of toxic levels of acetylcholine (ACh) at the synaptic junctions and thus induces muscarinic and nicotinic receptors stimulation. However, other mechanisms have recently been described. Central nervous system (CNS) depression particularly on respiratory and vasomotor centers may induce respiratory failure and cardiac arrest. Intermediate syndrome after NAs exposure is less common than OP pesticides poisoning. There are four approaches to detect exposure to NAs in biological samples: (I) AChE activity measurement, (II) Determination of hydrolysis products in plasma and urine, (III) Fluoride reactivation of phosphylated binding sites and (IV) Mass spectrometric determination of cholinesterase adducts. The clinical manifestations are similar to OP pesticides poisoning, but with more severity and fatalities. The management should be started as soon as possible. The victims should immediately be removed from the field and treatment is commenced with auto-injector antidotes (atropine and oximes) such as MARK I kit. A 0.5% hypochlorite solution as well as novel products like M291 Resin kit, G117H and Phosphotriesterase isolated from soil bacterias, are now available for decontamination of NAs. Atropine and oximes are the well known antidotes that should be infused as clinically indicated. However, some new adjuvant and additional treatment such as magnesium sulfate, sodium bicarbonate, gacyclidine, benactyzine, tezampanel, hemoperfusion, antioxidants and bioscavengers have recently been used for OP NAs poisoning. PMID:23351280

The Equipment of Czech Firefighters for the Detection and Field Analyses of Chemical Warfare Agents

Directory of Open Access Journals (Sweden)

Jana Krykorkova

2014-05-01

Full Text Available This paper describes the requirements for the devices of detection, chemical reconnaissance and field analyses of chemical warfare agents (CWA and divides them into simple devices of detection, universal detectors, selective analyzers, multi-component analyzers and mobile laboratories. It also describes the devices of detection available within the Fire and Rescue Service of the Czech Republic (FRS CR and compares them with some prospective trends of further development.

Persistent myalgia following whiplash.

Science.gov (United States)

Dommerholt, Jan

2005-10-01

Persistent myalgia following whiplash is commonly considered the result of poor psychosocial status, illness behavior, or failing coping skills. However, there is much evidence that persistent myalgia may be due to neurophysiologic mechanisms involving peripheral and central sensitization. Myofascial trigger points may play a crucial role in maintaining sensitization. Recent research suggests that the chemical environment of myofascial trigger points is an important factor. Several consequences are reviewed when central pain mechanisms and myofascial trigger points are included in the differential diagnosis and in the management of patients with persistent pain following whiplash.

Natural Attenuation of the Persistent Chemical Warfare Agent ...

Science.gov (United States)

Report This project studied the influence of temperature on the natural attenuation of VX from five types of porous/permeable materials: unsealed concrete, plywood, rubber escalator handrail, high density polyethylene (HDPE) plastic, and acoustic ceiling tile.

Advantages of paramagnetic chemical exchange saturation transfer (CEST) complexes having slow to intermediate water exchange properties as responsive MRI agents.

Science.gov (United States)

Soesbe, Todd C; Wu, Yunkou; Dean Sherry, A

2013-07-01

Paramagnetic chemical exchange saturation transfer (PARACEST) complexes are exogenous contrast agents that have great potential to further extend the functional and molecular imaging capabilities of magnetic resonance. As a result of the presence of a central paramagnetic lanthanide ion (Ln(3+) ≠ La(3+) , Gd(3+) , Lu(3+) ) within the chelate, the resonance frequencies of exchangeable protons bound to the PARACEST agent are shifted far away from the bulk water frequency. This large chemical shift, combined with an extreme sensitivity to the chemical exchange rate, make PARACEST agents ideally suited for the reporting of significant biological metrics, such as temperature, pH and the presence of metabolites. In addition, the ability to turn PARACEST agents 'off' and 'on' using a frequency-selective saturation pulse gives them a distinct advantage over Gd(3+) -based contrast agents. A current challenge for PARACEST research is the translation of the promising in vitro results into in vivo systems. This short review article first describes the basic theory behind PARACEST contrast agents, their benefits over other contrast agents and their applications to MRI. It then describes some of the recent PARACEST research results: specifically, pH measurements using water molecule exchange rate modulation, T2 exchange contrast caused by water molecule exchange, the use of ultrashort TEs (TE < 10 µs) to overcome T2 exchange line broadening and the potential application of T2 exchange as a new contrast mechanism for MRI. Copyright © 2012 John Wiley & Sons, Ltd.

A Comparison of Predictive Thermo and Water Solvation Property Prediction Tools and Experimental Data for Selected Traditional Chemical Warfare Agents and Simulants II: COSMO RS and COSMOTherm

Science.gov (United States)

2017-04-01

SELECTED TRADITIONAL CHEMICAL WARFARE AGENTS AND SIMULANTS II: COSMO-RS AND COSMOTHERM ECBC-TR-1454 Jerry B. Cabalo RESEARCH AND TECHNOLOGY...Traditional Chemical Warfare Agents and Simulants II: COSMO-RS and COSMOTherm 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER CB10115...in the ADF 2012 suite of programs for the physico- chemical properties of a set of traditional chemical warfare agents and selected simulants. To

Improving Blood Monitoring of Enzymes as Biomarkers of Risk from Anticholinergic Pesticides and Chemical Warfare Agents

National Research Council Canada - National Science Library

Wilson, Barry W

2006-01-01

Blood biomarkers are an important way to monitor exposure to anticholinergic pesticides and chemical warfare agents and to establish whether some personnel are at greater risk than others from exposure...

Improving Blood Monitoring of Enzymes as Biomarkers of Risk from Anticholinergic Pesticides and Chemical Warfare Agents

National Research Council Canada - National Science Library

Wilson, Barry W

2005-01-01

Blood biomarkers are an important way to monitor exposure to anticholinergic pesticides and chemical warfare agents and to establish whether some personnel are at greater risk than others from exposure...

Evaluation of liquid-phase oxidation for the destruction of potential chemical terrorism agents

Energy Technology Data Exchange (ETDEWEB)

Thouin, G.; Harrison, S.; Li, K.; Kuang, W.; Volchek, K.; Fingas, M. [Environment Canada, Ottawa, ON (Canada). Emergencies Science Div; Potaraju, S.; Velicogna, D.; Obenauf, A. [SAIC Canada, Ottawa, ON (Canada)

2005-07-01

Although pesticides are designed to protect crops and livestock against insects, fungi or nuisance plants, the toxicity of these compounds is not limited to target species. Organophosphorus, organochlorine and carbamate pesticides all target the nervous systems of insects. This paper assessed the effectiveness of an enhanced oxidation process using peroxycarboxylic acids for the liquid-phase destruction of toxic industrial chemicals, considered to be potential agents of chemical terrorism. Peroxyacetic acid (PAA) and peroxypropionic acid (PPA) were tested as decontamination agents on organophosphorus, organochlorine and carbamate pesticides. The processes were reviewed in relation to the terms of percent agent destruction over time, with a target of 90 per cent destruction within 30 minutes. Effectiveness was also assessed on the accumulation of toxic by-products. A background of the pesticides was presented, as well as details of their various applications. The molecular structures of the compounds were also provided. Oxidation extraction procedures, materials and methods were also presented, as well as analytical techniques, method detection limits and issues concerning reproducibility. The pH profile of PAA and PPA as a function of the concentration in acid was studied in order to determine which was more likely to be corrosive. It was concluded that peroxycarboxylic acids are effective decontamination agents for organophosphorous and carbamate pesticides. PAA and PPA are equally effective in degrading the examined pesticides, however, greater amounts of toxic by-products are found with PPA than with PAA. Neither PAA nor PPA were able to degrade lindane, and more lindane was found in the treated samples than in the controls. It was noted that time profiles for lower concentrations of peroxycarboxylic acids and pH profiles are currently being developed. It was suggested that further research in this area included degradation experiments on various types of

Computational enzymology for degradation of chemical warfare agents: promising technologies for remediation processes

Directory of Open Access Journals (Sweden)

2017-03-01

Full Text Available Chemical weapons are a major worldwide problem, since they are inexpensive, easy to produce on a large scale and difficult to detect and control. Among the chemical warfare agents, we can highlight the organophosphorus compounds (OP, which contain the phosphorus element and that have a large number of applications. They affect the central nervous system and can lead to death, so there are a lot of works in order to design new effective antidotes for the intoxication caused by them. The standard treatment includes the use of an anticholinergic combined to a central nervous system depressor and an oxime. Oximes are compounds that reactivate Acetylcholinesterase (AChE, a regulatory enzyme responsible for the transmission of nerve impulses, which is one of the molecular targets most vulnerable to neurotoxic agents. Increasingly, enzymatic treatment becomes a promising alternative; therefore, other enzymes have been studied for the OP degradation function, such as phosphotriesterase (PTE from bacteria, human serum paraoxonase 1 (HssPON1 and diisopropyl fluorophosphatase (DFPase that showed significant performances in OP detoxification. The understanding of mechanisms by which enzymes act is of extreme importance for the projection of antidotes for warfare agents, and computational chemistry comes to aid and reduce the time and costs of the process. Molecular Docking, Molecular Dynamics and QM/MM (quantum-mechanics/molecular-mechanics are techniques used to investigate the molecular interactions between ligands and proteins.

Agent Orange Exposure and 2,3,7,8-Tetrachlorodibenzo-p-Dioxin (TCDD) in Human Milk.

Science.gov (United States)

Scialli, Anthony R; Watkins, Deborah K; Ginevan, Michael E

2015-06-01

Agent Orange was sprayed in parts of southern Vietnam during the U.S.-Vietnam war and was a mixture of two chlorophenoxy herbicides. The mixture was contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). TCDD and other dioxins and furans are measurable in the milk of Vietnamese women. We explored whether the TCDD in milk from these women was from Agent Orange and whether lactational exposure can be a mode of transgenerational effects of TCDD from Agent Orange. A review of the world's literature on milk concentrations of polychlorinated compounds showed the presence of TCDD and other dioxins and furans in all countries that have been assessed. The congener profile of these chemicals, that is, the proportion of different congeners in the sample, can be used to assess the source of milk contamination. Measurements in most countries, including contemporary measurements in Vietnam, are consistent with non-Agent Orange exposure sources, including industrial activities and incineration of waste. Models and supporting human data suggest that TCDD from breastfeeding does not persist in a child past adolescence and that the adult body burden of TCDD is independent of whether the individual was breast- or bottle-fed as a child. These findings suggest that exposure to Agent Orange in Vietnam did not result in persistent transgenerational exposure through human milk. © 2015 Wiley Periodicals, Inc.

Technology assessment for the determination of chemical agent vapors in demilitarization facilities: Final report

Energy Technology Data Exchange (ETDEWEB)

Maskarinec, M.P.; Wise, M.B.; Buchanan, M.V.

1987-01-01

A survey of analytical methods for the determination of chemical agents GB, VX, and HD was made. HD, or mustard, is bis-2-chloroethyl sulfide, and is classified as a blishtering agent. GB, or Sarin, is isopropyl methyl phosphonofluoridate. VX is O-ethyl-S-(2-diisopropylaminoethyl)methylphosphonothioate. Both GB and VX are nerve agents. Included were methods capable of providing for monitoring requirements at the time weighted average (TWA) and allowable stack concentration (ASC) levels in near real time. A review of the currently used automatic continuous air monitoring system (ACAMS) was made as well as a review of the recently developed atmospheric pressure ionization mass spectrometry (APIMS). This report recommends a strategy for research and development for near term and medium term improvement of the overall monitoring program. 12 refs., 1 tab.

Methyl salicylate: a reactive chemical warfare agent surrogate to detect reaction with hypochlorite.

Science.gov (United States)

Salter, W Bruce; Owens, Jeffery R; Wander, Joseph D

2011-11-01

Methyl salicylate (MeS) has a rich history as an inert physical simulant for the chemical warfare agents sulfur mustard and soman, where it is used extensively for liquid- and vapor-permeation testing. Here we demonstrate possible utility of MeS as a reactivity simulant for chlorine-based decontaminants. In these experiments MeS was reacted with sodium hypochlorite varying stoichiometry, temperature, reaction time, and pH. No colored oxidation products were observed; however, chlorination of the aromatic ring occurred ortho (methyl 3-chlorosalicylate) and para (methyl 5-chlorosalicylate) to the position bearing the -OH group in both the mono- and disubstituted forms. The monosubstituted para product accumulated initially, and the ortho and 3,5-dichloro products formed over the next several hours. Yields from reactions conducted below pH 11 declined rapidly with decreasing pH. Reactions run at 40 °C produced predominantly para substitution, while those run at 0 °C produced lower yields of ortho- and para-substituted products. Reactions were also carried out on textile substrates of cotton, 50/50 nylon-cotton, and a meta aramid. The textile data broadly reproduced reaction times and stoichiometry observed in the liquid phase, but are complicated by physical and possibly chemical interactions with the fabric. These data indicate that, for hypochlorite-containing neutralizing agents operating at strongly alkaline pH, one can expect MeS to react stoichiometrically with the hypochlorite it encounters. This suggests utility of MeS in lieu of such highly hazardous surrogates as monochloroalkyl sulfides as a simulant for threat scenarios involving the stoichiometric decomposition of sulfur mustard. Specifically, the extent of coverage of the simulant on a fabric by the neutralizing agent can be directly measured. Similar reactivity toward other halogen oxidizing agents is likely but remains to be demonstrated.

Persistence of sister chromatid exchanges and in vitro morphological transformation of Syrian hamster fetal cells by chemical and physical carcinogens

International Nuclear Information System (INIS)

Popescu, N.C.; Amsbaugh, S.C.; DiPaolo, J.A.

1985-01-01

The induction of neoplastic cell transformation is closely associated with DNA alterations which occur shortly after carcinogen exposure. Sister chromatid exchange (SCE) formation is a sensitive indicator of carcinogen-DNA interaction and correlates with the induction of morphological cell transformation. The persistence of lesions generating SCE produced by chemical and physical carcinogens and its relevance to the induction of morphologic transformation was evaluated in coordinated experiments with cultured Syrian hamster fetal cells (HFC). Exponentially growing HFC were exposed for 1 h to benzo[a]pyrene (BP), methyl-methanesulfonate (MMS), cis-platinum (II) diaminedichloride (cis Pt II), N-methyl-N'-nitrosourea (MNU), mitomycin C (MMC), N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), N-acetoxy-2-fluorenyl-acetamide (AcAAF) or u.v. light irradiated. SCE analysis demonstrates that for a period of 48 h after carcinogen exposure, during which time the cells undergo at least four replicative cycles, DNA damage generating SCE induced by all chemical carcinogens either persisted or was partially removed, whereas u.v.-induced lesions were completely removed. An elevated SCE frequency persisted after two additional cell cycles after treatment with BP, AcAAF or MMC without increased cell lethality as compared to other carcinogens whose lesions were completely eliminated during the same period

A Review of Chemical Warfare Agent (CWA) Detector Technologies and Commercial-Off-The-Shelf Items

Science.gov (United States)

2009-03-01

Environmental Health Perspectives 1994, 102, 18-38. 21. La Franchi , P., Chemical and Biological Weapons: The War from Hell. ADM September, 1995, pp 9-10...One-to-Five Gas Monitor with VOC Detection. In ENVCO Global . DSTO-GD-0570 98 152. MultiRAE Plus. In RAE Systems: San Jose, CA. 153. ToxiRAE Plus PID...158. Rippen, M., Chemical and Biological Agent Sensor/Detector Systems Technology Development for Applications in the Global War on Terrorism. In

Chemical modification of cobalt ferrite nanoparticles with possible application as asphaltene flocculant agent

Energy Technology Data Exchange (ETDEWEB)

Oliveira, G.E.; Clarindo, J.E.S.; Santo, K.S.E., E-mail: geiza.oliveira@ufes.br [Universidade Federal do Espirito Santo (CCE/DQUI/UFES), Vitoria, ES (Brazil). Centro de Ciencias Exatas. Dept. de Quimica; Souza Junior, F.G. [Universidade Federal do Rio de Janeiro (IMA/UFRJ), Rio de Janeiro, RJ (Brazil). Instituto de Macromoleculas

2013-11-01

Asphaltenes can cause enormous losses in the oil industry, because they are soluble only in aromatic solvents. Therefore, they must be removed from the petroleum before it is refined, using flocculant agents. Aiming to find new materials that can work as flocculant agents to asphaltenes, cobalt ferrite nanoparticles were chemically modified through acid-base reactions using dodecylbenzene sulfonic acid (DBSA) to increase their lipophilicity. Nanoparticle synthesis was performed using the co-precipitation method followed by annealing of these nanoparticles, aiming to change the structural phase. Modified and unmodified nanoparticles were tested by FTIR-ATR, XRD and TGA/DTA. In addition, precipitation onset of the asphaltenes was performed using modified and unmodified nanoparticles. These tests showed that modified nanoparticles have a potential application as flocculant agents used to remove asphaltenes before oil refining, since the presence of nanoparticles promotes the asphaltene precipitation onset with the addition of a small amount of non-solvent (author)

Chemical modification of cobalt ferrite nanoparticles with possible application as asphaltene flocculant agent

International Nuclear Information System (INIS)

Oliveira, G.E.; Clarindo, J.E.S.; Santo, K.S.E.; Souza Junior, F.G.

2013-01-01

Asphaltenes can cause enormous losses in the oil industry, because they are soluble only in aromatic solvents. Therefore, they must be removed from the petroleum before it is refined, using flocculant agents. Aiming to find new materials that can work as flocculant agents to asphaltenes, cobalt ferrite nanoparticles were chemically modified through acid-base reactions using dodecylbenzene sulfonic acid (DBSA) to increase their lipophilicity. Nanoparticle synthesis was performed using the co-precipitation method followed by annealing of these nanoparticles, aiming to change the structural phase. Modified and unmodified nanoparticles were tested by FTIR-ATR, XRD and TGA/DTA. In addition, precipitation onset of the asphaltenes was performed using modified and unmodified nanoparticles. These tests showed that modified nanoparticles have a potential application as flocculant agents used to remove asphaltenes before oil refining, since the presence of nanoparticles promotes the asphaltene precipitation onset with the addition of a small amount of non-solvent (author)

Demonstration of spread-on peel-off consumer products for sampling surfaces contaminated with pesticides and chemical warfare agent signatures.

Science.gov (United States)

Behringer, Deborah L; Smith, Deborah L; Katona, Vanessa R; Lewis, Alan T; Hernon-Kenny, Laura A; Crenshaw, Michael D

2014-08-01

A terrorist attack using toxic chemicals is an international concern. The utility of rubber cement and latex body paint as spray-on/spread-on peel-off collection media for signatures attributable to pesticides and chemical warfare agents from interior building and public transportation surfaces two weeks post-deposition is demonstrated. The efficacy of these media to sample escalator handrail, stainless steel, vinyl upholstery fabric, and wood flooring is demonstrated for two pesticides and eight chemicals related to chemical warfare agents. The chemicals tested are nicotine, parathion, atropine, diisopropyl methylphosphonate, dimethyl methylphosphonate, dipinacolyl methylphosphonate, ethyl methylphosphonic acid, isopropyl methylphosphonic acid, methylphosphonic acid, and thiodiglycol. Amounts of each chemical found are generally greatest when latex body paint is used. Analytes with low volatility and containing an alkaline nitrogen or a sulfur atom (e.g., nicotine and parathion) usually are recovered to a greater extent than the neutral phosphonate diesters and acidic phosphonic acids (e.g., dimethyl methylphosphonate and ethyl methylphosphonic acid). Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Influence of chemical agents on the surface area and porosity of active carbon hollow fibers

Directory of Open Access Journals (Sweden)

LJILJANA M. KLJAJEVIĆ

2011-09-01

Full Text Available Active carbon hollow fibers were prepared from regenerated polysulfone hollow fibers by chemical activation using: disodium hydrogen phosphate 2-hydrate, disodium tetraborate 10-hydrate, hydrogen peroxide, and diammonium hydrogen phosphate. After chemical activation fibers were carbonized in an inert atmosphere. The specific surface area and porosity of obtained carbons were studied by nitrogen adsorption–desorption isotherms at 77 K, while the structures were examined with scanning electron microscopy and X-ray diffraction. The activation process increases these adsorption properties of fibers being more pronounced for active carbon fibers obtained with disodium tetraborate 10-hydrate and hydrogen peroxide as activator. The obtained active hollow carbons are microporous with different pore size distribution. Chemical activation with phosphates produces active carbon material with small surface area but with both mesopores and micropores. X-ray diffraction shows that besides turbostratic structure typical for carbon materials, there are some peaks which indicate some intermediate reaction products when sodium salts were used as activating agent. Based on data from the electrochemical measurements the activity and porosity of the active fibers depend strongly on the oxidizing agent applied.

Persistent organic pollutants–are our methods sensitive and selective enough?

NARCIS (Netherlands)

de Boer, J.

2012-01-01

Due to the exponential growth of the world population and a strong worldwide economic development, humans are increasingly exposed to chemicals. This is particularly true for persistent, toxic chemicals that accumulate in organisms including humans. The presence of these persistent organic

Chemical agent recoveries

Data.gov (United States)

U.S. Environmental Protection Agency — Dataset shows the calculation of reported decontamination efficacies from the raw data (i.e., measured amount of chemical recovered from test coupons and positive...

[The development of neurotoxic agents as chemical weapons during the National Socialist period in Germany].

Science.gov (United States)

López-Muñoz, F; Alamo, C; Guerra, J A; García-García, P

The discovery and development of the so-called 'nerve agents' (neurotoxic substances to be used as weapons) took place in the Third Reich, largely thanks to the vast amount of progress being made in pharmacology in Germany at that time, both in academic and industrial terms. Furthermore, successive National Socialist governments set up a collaborative network made up of the academia, the chemical industry and military chiefs that also favoured this line of research. The first neurotoxic substance to be incorporated into the category of 'chemical warfare agent' did so almost wholly by chance. As part of the work being carried out on organophosphate-type pesticides and insecticides, Gerald Schrader, a chemist at the I.G. Farben company, synthesised tabun (ethyl N,N-dimethylphosphoramidocyanidate) and an incident involving accidental contamination of laboratory staff with this substance highlighted its potential toxicity. The same group of researchers later synthesised another substance with the same properties, sarin (isopropyl methylphosphonofluoridate). Both agents were studied for use as chemical weapons by Wolfgang Wirth. At the same time, a group led by Richard Kuhn, who won the Nobel Prize in Chemistry in 1938, synthesised pinacolyl methylphosphonofluoridate, otherwise known as soman. Pharmacological studies confirmed that the neurotoxic mechanism of action of these substances was the irreversible inhibition of the enzyme acetylcholinesterase, which is responsible for metabolising acetylcholine. Results also showed that an excess of this neurotransmitter led to a continuous over-stimulation of the cholinergic (nicotinic and muscarinic) receptors, which is what triggers the appearance of the wide range of symptoms of poisoning and their swift fatal effect.

Laser mass spectrometry of chemical warfare agents using ultrashort laser pulses

International Nuclear Information System (INIS)

Weickhardt, C.; Grun, C.; Grotemeyer, J.

1998-01-01

Fast relaxation processes in excited molecules such as IC, ISC, and fragmentation are observed in many environmentally and technically relevant substances. They cause severe problems to resonance ionization mass spectrometry because they reduce the ionization yield and lead to mass spectra which do not allow the identification of the compound. By the use of ultrashort laser pulses these problems can be overcome and the advantages of REMPI over conventional ionization techniques in mass spectrometry can be regained. This is demonstrated using soil samples contaminated with a chemical warfare agent

Prophylaxis and Therapy Against Chemical Agents

Science.gov (United States)

2009-11-01

Hematopoietic Consequences F. Dorandeu 5) pH Dependent Toxicity of Sulphur Mustard In Vitro J. Mikler Nerve Agents / Scavengers 1) Mutagenesis...symptoms such as salivation or shortness of breath and lower level exposures could be rendered inconsequential. B.2 CURRENT THERAPY FOR NERVE AGENT

Analysis of Chemical Warfare Agents: General Overview, LC-MS Review, In-House LC-ESI-MS Methods and Open Literature Bibliography

National Research Council Canada - National Science Library

D'Agostino, Paul A; Chenier, C. L

2006-01-01

Ratification of the Chemical Weapons Convention by more than 165 States Parties has reduced the risk of chemical warfare agent use, but there still remains a concern that other parties may make use...

Hyperthyroidism as a cause of persistent vomiting.

Science.gov (United States)

Hoogendoorn, E H; Cools, B M

2004-09-01

A 32-year-old woman presented with persistent vomiting, epigastric pain and weight loss. A sinus tachycardia was the clue to the diagnosis of hyperthyroidism due to Graves' disease. On treatment with propylthiouracil and a beta-blocking agent, her symptoms resolved within one day, even though her free thyroxine level was still high. Hyperthyroidism is an uncommon, but previously reported cause of persistent vomiting.

Hyperthyroidism as a cause of persistent vomiting.

OpenAIRE

Hoogendoorn, E.H.; Cools, B.M.

2004-01-01

A 32-year-old woman presented with persistent vomiting, epigastric pain and weight loss. A sinus tachycardia was the clue to the diagnosis of hyperthyroidism due to Graves' disease. On treatment with propylthiouracil and a beta-blocking agent, her symptoms resolved within one day, even though her free thyroxine level was still high. Hyperthyroidism is an uncommon, but previously reported cause of persistent vomiting.

The possible role of intravenous lipid emulsion in the treatment of chemical warfare agent poisoning

Directory of Open Access Journals (Sweden)

Arik Eisenkraft

Full Text Available Organophosphates (OPs are cholinesterase inhibitors that lead to a characteristic toxidrome of hypersecretion, miosis, dyspnea, respiratory insufficiency, convulsions and, without proper and early antidotal treatment, death. Most of these compounds are highly lipophilic. Sulfur mustard is a toxic lipophilic alkylating agent, exerting its damage through alkylation of cellular macromolecules (e.g., DNA, proteins and intense activation of pro-inflammatory pathways. Currently approved antidotes against OPs include the peripheral anticholinergic drug atropine and an oxime that reactivates the inhibited cholinesterase. Benzodiazepines are used to stop organophosphate-induced seizures. Despite these approved drugs, efforts have been made to introduce other medical countermeasures in order to attenuate both the short-term and long-term clinical effects following exposure. Currently, there is no antidote against sulfur mustard poisoning. Intravenous lipid emulsions are used as a source of calories in parenteral nutrition. In recent years, efficacy of lipid emulsions has been shown in the treatment of poisoning by fat-soluble compounds in animal models as well as clinically in humans. In this review we discuss the usefulness of intravenous lipid emulsions as an adjunct to the in-hospital treatment of chemical warfare agent poisoning. Keywords: Intravenous lipid emulsion, Organophosphates, Sulfur mustard, Antidotes, Poisoning, Chemical Warfare agents

Studies of the action of chemical agents on the heart. Annual report, February 1985-February 1986

Energy Technology Data Exchange (ETDEWEB)

Hassler, G.R.; Moutvic, R.R.

1986-03-01

This report describes initial studies to determine the subchronic effect of Soman and Sarin, on the electrical, mechanical, and neurochemical properties of the heart. Two different animal models are under development. The electrophysiologic and hemodynamic aspects of survival doses of chemical agent are begin studied in the dog. Two chronically instrumented dog models have been developed. The first is a hemodynamic dog model in which long-term measurements of left and right heart pressures, aortic flow, coronary flow as well as epicardial electrocardiograms, are monitored. The animals will be monitored at baseline and for one month following exposure in survival of a chemical-warfare-agent insult. These animals are stressed via treadmill exercise. The electrophysiology dog model consists of chronically implanted electrodes for performance of repetitive ventricular response stimulation, His bundle recording, and ECG analysis. Measurements are made prior to, and for one month following, exposure to survivable doses of CW agent. This dog model is further probed by sequential administration of various pharmacologic agents designed to study the autonomic status of the heart. All dogs and a limited number of the guinea pigs will be continuously monitored for occurrence of arrhythmic events utilizing Holter monitoring technology. The guinea pig neurochemical studies will include acetylcholines, choline acetyltransferase activity, QNB binding, choline uptake, norepinephrine levels and turnover, and norepinephrine uptake experiments.

Reducing Mortality from Terrorist Releases of Chemical and Biological Agents: I. Filtration for Ventilation Systems in Commercial Building

Energy Technology Data Exchange (ETDEWEB)

Thatcher, Tracy L.; Daisey, Joan M.

1999-09-01

There is growing concern about potential terrorist attacks involving releases of chemical and/or biological (CB) agents, such as sarin or anthrax, in and around buildings. For an external release, the CB agent can enter the building through the air intakes of a building's mechanical ventilation system and by infiltration through the building envelope. For an interior release in a single room, the mechanical ventilation system, which often recirculates some fraction of the air within a building, may distribute the released CB agent throughout the building. For both cases, installing building systems that remove chemical and biological agents may be the most effective way to protect building occupants. Filtration systems installed in the heating, ventilating and air-conditioning (HVAC) systems of buildings can significantly reduce exposures of building occupants in the event of a release, whether the release is outdoors or indoors. Reduced exposures can reduce the number of deaths from a terrorist attack. The purpose of this report is to provide information and examples of the design of filtration systems to help building engineers retrofit HVAC systems. The report also provides background information on the physical nature of CB agents and brief overviews of the basic principles of particle and vapor filtration.

Iron-montmorillonite clays as active sorbents for the decontamination of hazardous chemical warfare agents.

Science.gov (United States)

Carniato, F; Bisio, C; Evangelisti, C; Psaro, R; Dal Santo, V; Costenaro, D; Marchese, L; Guidotti, M

2018-02-27

A class of heterogeneous catalysts based on commercial bentonite from natural origin, containing at least 80 wt% of montmorillonite clay, was designed to transform selectively and under mild conditions toxic organosulfur and organophosphorus chemical warfare agents into non-noxious products with a reduced impact on health and environment. The bentonite from the natural origin was modified by introducing iron species and acid sites in the interlayer space, aiming to obtain a sorbent with strong catalytic oxidising and hydrolytic properties. The catalytic performance of these materials was evaluated in the oxidative abatement of (2-chloroethyl)ethyl sulfide (CEES), a simulant of sulfur mustard, in the presence of aqueous hydrogen peroxide as an oxidant. A new decontamination formulation was, moreover, proposed and obtained by mixing sodium perborate, as a solid oxidant, to iron-bentonite catalysts. Solid-phase decontamination tests, performed on a cotton textile support contaminated with organosulfide and organophosphonate simulant agents revealed the good activity of the solid formulation, especially in the in situ detoxification of blistering agents. Tests carried out on the real blistering warfare agent, sulfur mustard (HD agent), showed that, thanks to the co-presence of the iron-based clay together with the solid oxidant component, a good decontamination of the test surface from the real warfare agent could be achieved (80% contaminant degradation, under ambient conditions, in 24 h).

METHOD FOR THE ESTIMATION OF SOIL VULNERABILITY AT THE CHEMICAL AGENTS IMPACT

Directory of Open Access Journals (Sweden)

Radu Lacatusu

2006-10-01

Full Text Available The negative effect induced to the soil by any impact, commonly chemical impact, defining the soil vulnerability to this impulse. To put in equation this soil characteristic, were chosen these physical and chemical indicators which determining the phenomenon intensity and its evolution direction, as: texture, pH (soil reaction, organic matter content, carbonates content and ion exchange capacity. Each of these indicators was divided into five classes, depending on the content in elements and/or chemical substances that defining any indicator, the specific indicator size, and on the direction and intensity of process generated by impact. Every of these five classes have been got marks from one to five according to soil capacity to putting up resistance to modification induced by impact. One mark reflecting the lowest impact resistance and five mark the highest ones. By summing of characteristic marks for each class resulted a scale from 5 to 25. According to this scale we could have very high soil vulnerability with only 5 points, and an invulnerable soil with 25 points. Analytical data of all these five physics and chemical indicators, determined for a specific territory, could be framing in vulnerability scale according to the presented methodology. This methodology permit to realize maps of the specific territories for soils vulnerability to impact of any nature chemical agents.

How Do I Know? A Guide to the Selection of Personal Protective Equipment for Use in Responding to A Release of Chemical Warfare Agents

Energy Technology Data Exchange (ETDEWEB)

Foust, C.B.

1999-05-01

An incident involving chemical warfare agents requires a unique hazardous materials (HAZMAT) response. As with an HAZMAT event, federal regulations prescribe that responders must be protected from exposure to the chemical agents. But unlike other HAZMAT events, special considerations govern selection of personal protective equipment (PPE). PPE includes all clothing, respirators and monitoring devices used to respond to a chemical release. PPE can differ depending on whether responders are military or civilian personnel.

Basic MR relaxation mechanisms and contrast agent design.

Science.gov (United States)

De León-Rodríguez, Luis M; Martins, André F; Pinho, Marco C; Rofsky, Neil M; Sherry, A Dean

2015-09-01

The diagnostic capabilities of magnetic resonance imaging (MRI) have undergone continuous and substantial evolution by virtue of hardware and software innovations and the development and implementation of exogenous contrast media. Thirty years since the first MRI contrast agent was approved for clinical use, a reliance on MR contrast media persists, largely to improve image quality with higher contrast resolution and to provide additional functional characterization of normal and abnormal tissues. Further development of MR contrast media is an important component in the quest for continued augmentation of diagnostic capabilities. In this review we detail the many important considerations when pursuing the design and use of MR contrast media. We offer a perspective on the importance of chemical stability, particularly kinetic stability, and how this influences one's thinking about the safety of metal-ligand-based contrast agents. We discuss the mechanisms involved in MR relaxation in the context of probe design strategies. A brief description of currently available contrast agents is accompanied by an in-depth discussion that highlights promising MRI contrast agents in the development of future clinical and research applications. Our intention is to give a diverse audience an improved understanding of the factors involved in developing new types of safe and highly efficient MR contrast agents and, at the same time, provide an appreciation of the insights into physiology and disease that newer types of responsive agents can provide. © 2015 Wiley Periodicals, Inc.

Setting up a mobile Lidar (DIAL) system for detecting chemical warfare agents

International Nuclear Information System (INIS)

Tehrani, M Kavosh; Jaafari, E; Mobashery, A; Mohammad, M Malek

2015-01-01

The mobile light detection and ranging DIAL system of Malek Ashtar University of Technology has been developed for the detection of chemical warfare agents whose absorption wavelengths are in the range of 9.2–10.8 μm tunable CO 2 lasers of the system. In this paper, this system is first described and then ammonia detection is analyzed experimentally. Also, experimental results of detecting a sarin agent simulant, dimethyl–methyl phosphonate (DMMP), are presented. The power levels received from different ranges to detect specific concentrations of NH 3 and DMMP have been measured and debated. The primary test results with a 150 ns clipped pulse width by passive pinhole plasma shutter indicate that the system is capable of monitoring several species of pollutants in the range of about 1 km, with a 20 m spatial and 2 min temporal resolution. (paper)

Vesicants and nerve agents in chemical warfare. Decontamination and treatment strategies for a changed world.

Science.gov (United States)

Devereaux, Asha; Amundson, Dennis E; Parrish, J S; Lazarus, Angeline A

2002-10-01

Vesicants and nerve agents have been used in chemical warfare for ages. They remain a threat in today's altered political climate because they are relatively simple to produce, transport, and deploy. Vesicants, such as mustard and lewisite, can affect the skin, eyes, respiratory system, and gastrointestinal system. They leave affected persons at risk for long-term effects. Nerve agents, such as tabun, sarin, soman, and VX, hyperstimulate the muscarinic and nicotinic receptors of the nervous system. Physicians need to familiarize themselves with the clinical findings of such exposures and the decontamination and treatment strategies necessary to minimize injuries and deaths.

Decontamination of adsorbed chemical warfare agents on activated carbon using hydrogen peroxide solutions.

Science.gov (United States)

Osovsky, Ruth; Kaplan, Doron; Nir, Ido; Rotter, Hadar; Elisha, Shmuel; Columbus, Ishay

2014-09-16

Mild treatment with hydrogen peroxide solutions (3-30%) efficiently decomposes adsorbed chemical warfare agents (CWAs) on microporous activated carbons used in protective garments and air filters. Better than 95% decomposition of adsorbed sulfur mustard (HD), sarin, and VX was achieved at ambient temperatures within 1-24 h, depending on the H2O2 concentration. HD was oxidized to the nontoxic HD-sulfoxide. The nerve agents were perhydrolyzed to the respective nontoxic methylphosphonic acids. The relative rapidity of the oxidation and perhydrolysis under these conditions is attributed to the microenvironment of the micropores. Apparently, the reactions are favored due to basic sites on the carbon surface. Our findings suggest a potential environmentally friendly route for decontamination of adsorbed CWAs, using H2O2 without the need of cosolvents or activators.

Estimated general population control limits for unitary agents in drinking water, milk, soil, and unprocessed food items. For use in reentry decision-making

Energy Technology Data Exchange (ETDEWEB)

Watson, A.P.; Adams, J.D.; Cerar, R.J.; Hess, T.L.; Kistner, S.L.; Leffingwell, S.S.; MacIntosh, R.G.; Ward, J.R.

1992-01-01

In the event of an unplanned release of chemical agent during any stage of the Chemical Stockpile Disposal Program (CSDP), the potential exists for contamination of drinking water, forage crops, grains, garden produce, and livestock. Persistent agents such as VX or sulfur mustard pose the greatest human health concern for reentry. This White Paper has been prepared to provide technical bases for these decisions by developing working estimates of agent control limits in selected environmental media considered principal sources of potential human exposure. To date, control limits for public exposure to unitary agents have been established for atmospheric concentrations only. The current analysis builds on previous work to calculate working estimates of control limits for ingestion and dermal exposure to potentially contaminated drinking water, milk, soil, and unprocessed food items such as garden produce. Information characterizing agent desorption from, and detection on or in, contaminated porous media are presently too developed to permit reasonable estimation of dermal exposure from this source. Thus, dermal contact with potentially contaminated porous surfaces is not considered in this document.

Poly High Internal Phase Emulsion for the Immobilization of Chemical Warfare Agents.

Science.gov (United States)

Wright, Alexander J; Main, Marcus J; Cooper, Nicholas J; Blight, Barry A; Holder, Simon J

2017-09-20

We report a facile method for the absorption (characterized by the weight/weight swelling degree, Q) of a variety of chemical warfare agents (CWAs); including sulfur mustard (HD) (Q = 40) and V-series (VM, VX, i-Bu-VX, n-Bu-VX) of nerve agents (Q ≥ 45) and a simulant, methyl benzoate (Q = 55), through the use of a poly(styrene-co-vinyl benzyl chloride-co-divinylbenzene) lightly cross-linked poly high internal phase emulsion (polyHIPE). By varying the vinyl benzyl chloride (VBC) content and the volume of the internal phase of the precursor emulsion it is demonstrated that absorption is facilitated both by the swelling of the polymer and the uptake of liquid in the pores. In particular the sample prepared from a 95% internal emulsion water content showed rapid swelling (<5 min to total absorption) and the ability to swell both from a monolithic state and from a compressed state, making these systems ideal practical candidates for the rapid immobilization of CWAs.

In-situ leaching of crownpoint, NM, uranium ore: Part 7 - Laboratory study of chemical agents for molybdenum restoration

International Nuclear Information System (INIS)

Strom, E.T.; Vogt, T.C.

1987-01-01

One possible drawback to the use of an in-situ leaching to recover uranium is the potential release of previously insoluble chemical species into the formation water. Before a pilot test of in-situ uranium leaching at Crownpoint, NM, was begun, extensive laboratory studies were undertaken to develop chemical methods for treating one possible contaminant, molybdenum (Mo). New Mexico regulations restrict the amount of Mo permissable in formation waters after leaching to less than 1 ppm. Two techniques to restore Mo after leaching were studied with core and pack tests. These studies suggest that if Mo restoration problems occur in the field, the use of precipitating agents such as Ca/sup 2+/ or reducing agents such as Fe/sup 2+/ may be helpful in ameliorating such problems

Imaging in Vivo Extracellular pH with a Single Paramagnetic Chemical Exchange Saturation Transfer Magnetic Resonance Imaging Contrast Agent

Directory of Open Access Journals (Sweden)

Guanshu Liu

2012-01-01

Full Text Available The measurement of extracellular pH (pHe has potential utility for cancer diagnoses and for assessing the therapeutic effects of pH-dependent therapies. A single magnetic resonance imaging (MRI contrast agent that is detected through paramagnetic chemical exchange saturation transfer (PARACEST was designed to measure tumor pHe throughout the range of physiologic pH and with magnetic resonance saturation powers that are not harmful to a mouse model of cancer. The chemical characterization and modeling of the contrast agent Yb3+-1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid, 10-o-aminoanilide (Yb-DO3A-oAA suggested that the aryl amine of the agent forms an intramolecular hydrogen bond with a proximal carboxylate ligand, which was essential for generating a practical chemical exchange saturation transfer (CEST effect from an amine. A ratio of CEST effects from the aryl amine and amide was linearly correlated with pH throughout the physiologic pH range. The pH calibration was used to produce a parametric pH map of a subcutaneous flank tumor on a mouse model of MCF-7 mammary carcinoma. Although refinements in the in vivo CEST MRI methodology may improve the accuracy of pHe measurements, this study demonstrated that the PARACEST contrast agent can be used to generate parametric pH maps of in vivo tumors with saturation power levels that are not harmful to a mouse model of cancer.

Disposal of chemical agents and munitions stored at Pine Bluff Arsenal, Pine Bluff, Arkansas. Final phase 1, Environmental report

Energy Technology Data Exchange (ETDEWEB)

Ensminger, J.T.; Hillsman, E.L.; Johnson, R.D.; Morrisey, J.A.; Staub, W.P.; Boston, C.R.; Hunsaker, D.B.; Leibsch, E.; Rickert, L.W.; Tolbert, V.R.; Zimmerman, G.P.

1991-09-01

The Pine Bluff Arsenal (PBA) near Pine Bluff, Arkansas, is one of eight continental United States (CONUS) Army installations where lethal unitary chemical agents and munitions are stored and where destruction of agents and munitions is proposed under the Chemical Stockpile Disposal Program (CSDP). The chemical agent inventory at PBA consists of approximately 12%, by weight, of the total US stockpile. The destruction of the stockpile is necessary to eliminate the risk to the public from continued storage and to dispose of obsolete and leaking munitions. In 1988 the US Army issued a Final Programmatic Environmental Impact Statement (FPEIS) for the CSDP that identified on-site disposal of agents and munitions as the environmentally preferred alternative (i.e., the alternative with the least potential to cause significant adverse impacts). The purpose of this report is to examine the proposed implementation of on-site disposal at PBA in light of more recent and more detailed data than those on which the FPEIS is based. New population data were used to compute fatalities using the same computation methods and values for all other parameters as in the FPEIS. Results indicate that all alternatives are indistinguishable when the potential health impacts to the PBA community are considered. However, risks from on-site disposal are in all cases equal to or less than risks from other alternatives. Furthermore, no unique resources with the potential to prevent or delay implementation of on-site disposal at PBA have been identified.

Establish an Agent-Simulant Technology Relationship (ASTR)

Science.gov (United States)

2017-04-14

collective protection; CP; decontamination ; decon; contamination avoidance; CA; chemical biological radiological; CBR 16. SECURITY CLASSIFICATION...Within chemical defense, the individual protection (IP), collective protection (CP), decontamination (decon), and contamination avoidance (CA...OT). c. Testing may use chemical warfare agent (CWA), biological warfare agent (BWA), radiological agent, or simulant (surrogate). A simulant is a

Nanostructured Metal Oxides for Stoichiometric Degradation of Chemical Warfare Agents.

Science.gov (United States)

Štengl, Václav; Henych, Jiří; Janoš, Pavel; Skoumal, Miroslav

2016-01-01

Metal oxides have very important applications in many areas of chemistry, physics and materials science; their properties are dependent on the method of preparation, the morphology and texture. Nanostructured metal oxides can exhibit unique characteristics unlike those of the bulk form depending on their morphology, with a high density of edges, corners and defect surfaces. In recent years, methods have been developed for the preparation of metal oxide powders with tunable control of the primary particle size as well as of a secondary particle size: the size of agglomerates of crystallites. One of the many ways to take advantage of unique properties of nanostructured oxide materials is stoichiometric degradation of chemical warfare agents (CWAs) and volatile organic compounds (VOC) pollutants on their surfaces.

Dual-Function Metal-Organic Framework as a Versatile Catalyst for Detoxifying Chemical Warfare Agent Simulants.

Science.gov (United States)

Liu, Yangyang; Moon, Su-Young; Hupp, Joseph T; Farha, Omar K

2015-12-22

The nanocrystals of a porphyrin-based zirconium(IV) metal-organic framework (MOF) are used as a dual-function catalyst for the simultaneous detoxification of two chemical warfare agent simulants at room temperature. Simulants of nerve agent (such as GD, VX) and mustard gas, dimethyl 4-nitrophenyl phosphate and 2-chloroethyl ethyl sulfide, have been hydrolyzed and oxidized, respectively, to nontoxic products via a pair of pathways catalyzed by the same MOF. Phosphotriesterase-like activity of the Zr6-containing node combined with photoactivity of the porphyrin linker gives rise to a versatile MOF catalyst. In addition, bringing the MOF crystals down to the nanoregime leads to acceleration of the catalysis.

Assessing the persistence of pharmaceuticals in the aquatic environment: Challenges and needs

Directory of Open Access Journals (Sweden)

Qingwei Bu

2016-09-01

Full Text Available Chemical’s persistence is known to be an important parameter applied for decades to identify persistent organic pollutants in hazard and/or risk assessments. Nevertheless it is greatly challenged in the case of emerging contaminants such as pharmaceuticals because the persistence of these chemicals could be more affected by environmental conditions. This fact brings more challenges to the current system for evaluating the persistence of chemical contaminants. In this paper, challenges in assessing the persistence of pharmaceuticals were identified, and more importantly research needs were addressed based on the existing data and knowledge.

[Interference for Various Quench Agents of Chemical Disinfectants on Detection of Endotoxin Activities in Water].

Science.gov (United States)

Zhang, Can; Liu, Wen-jun; Shi, Yun; An, Dai-zhi; Bai, Miao; Xu, Wen

2015-05-01

The quenching agents such as histidine, glycine, ascorbic acid, Tween-80, sodium sulfite and sodium hyposulfite are commonly used for quenching the residual disinfectant in water. In this paper, in order to select the optimal type and concentration range of quenching agents prior to the Limulus assays, the interference effects of each quenching agent at different concentrations on endotoxin detection were investigated by the Limulus assays of kinetic-turbidity. Our results identified that, as for 0-1.0% concentration of histidine, ascorbic acid, Tween-80, sodium sulfite (pH unadjusted and pH neutral), interference on the Limulus assays was existed. Hence, these quenching agents could not be applied as neutralizers prior to Limulus assays. Although, there was no interference on endotoxin detection for the glycine, a yellow color, developed by the quenching products of glycine and glutaric dialdehyde, contributed to false positive results. Hence, glycine should not be used as quenching agents in Limulus assays for samples containing glutaric dialdehyde. Compared with other quenching agents as histidine, glycine, ascorbic acid, Tween-80, sodium sulfite, 0-1.0% concentration of sodium hyposulfite elicited no obvious interference, while 1.0%-5.0% concentration of sodium hyposulfite illustrated exhibition effect for endotoxin detection. All in all, compared with other quenching agents as histidine, glycine, ascorbic acid, Tween-80 and sodium sulfite, sodium hyposulfite is suitable for quenching chemicals prior to endotoxin detection and less than 0.5% of concentration is allowable.

Decontamination issues for chemical and biological warfare agents: how clean is clean enough?

Science.gov (United States)

Raber, E; Jin, A; Noonan, K; McGuire, R; Kirvel, R D

2001-06-01

The objective of this assessment is to determine what level of cleanup will be required to meet regulatory and stakeholder needs in the case of a chemical and/or biological incident at a civilian facility. A literature review for selected, potential chemical and biological warfare agents shows that dose information is often lacking or controversial. Environmental regulatory limits or other industrial health guidelines that could be used to help establish cleanup concentration levels for such agents are generally unavailable or not applicable for a public setting. Although dose information, cleanup criteria, and decontamination protocols all present challenges to effective planning, several decontamination approaches are available. Such approaches should be combined with risk-informed decision making to establish reasonable cleanup goals for protecting health, property, and resources. Key issues during a risk assessment are to determine exactly what constitutes a safety hazard and whether decontamination is necessary or not for a particular scenario. An important conclusion is that cleanup criteria are site dependent and stakeholder specific. The results of a modeling exercise for two outdoor scenarios are presented to reinforce this conclusion. Public perception of risk to health, public acceptance of recommendations based on scientific criteria, political support, time constraints, and economic concerns must all be addressed in the context of a specific scenario to yield effective and acceptable decontamination.

Oxidative treatment characteristics of biotreated textile-dyeing wastewater and chemical agents used in a textile-dyeing process by advanced oxidation process.

Science.gov (United States)

Lim, B R; Hu, H Y; Ahn, K H; Fujie, K

2004-01-01

The oxidative treatment characteristics of biotreated textile-dyeing wastewater and typical chemicals such as desizing, scouring, dispersing and swelling agents used in the textile-dyeing process by advanced oxidation process were experimentally studied. The refractory organic matters remained in the effluent of biological treatment process without degradation may be suitable for the improvement of biodegradability and mineralized to CO2 by combined ozonation with and without hydrogen peroxide. On the other hand, the refractory chemicals contained in the scouring agent A and swelling agent may not be mineralized and their biodegradability may not be improved by ozonation. However, the BOD/DOC ratio of scouring agent B increased from 0.3 to 0.45 after ozonation. Based on the results described above, advanced treatment process involving the ozonation without and with the addition of hydrogen peroxide, followed by biological treatment was proposed for the treatment of refractory wastewater discharged from the textile-dyeing process.

Emotional persistence in online chatting communities

Science.gov (United States)

Garas, Antonios; Garcia, David; Skowron, Marcin; Schweitzer, Frank

2012-05-01

How do users behave in online chatrooms, where they instantaneously read and write posts? We analyzed about 2.5 million posts covering various topics in Internet relay channels, and found that user activity patterns follow known power-law and stretched exponential distributions, indicating that online chat activity is not different from other forms of communication. Analysing the emotional expressions (positive, negative, neutral) of users, we revealed a remarkable persistence both for individual users and channels. I.e. despite their anonymity, users tend to follow social norms in repeated interactions in online chats, which results in a specific emotional ``tone'' of the channels. We provide an agent-based model of emotional interaction, which recovers qualitatively both the activity patterns in chatrooms and the emotional persistence of users and channels. While our assumptions about agent's emotional expressions are rooted in psychology, the model allows to test different hypothesis regarding their emotional impact in online communication.

Ultra-Fast Degradation of Chemical Warfare Agents Using MOF-Nanofiber Kebabs.

Science.gov (United States)

Zhao, Junjie; Lee, Dennis T; Yaga, Robert W; Hall, Morgan G; Barton, Heather F; Woodward, Ian R; Oldham, Christopher J; Walls, Howard J; Peterson, Gregory W; Parsons, Gregory N

2016-10-10

The threat associated with chemical warfare agents (CWAs) motivates the development of new materials to provide enhanced protection with a reduced burden. Metal-organic frame-works (MOFs) have recently been shown as highly effective catalysts for detoxifying CWAs, but challenges still remain for integrating MOFs into functional filter media and/or protective garments. Herein, we report a series of MOF-nanofiber kebab structures for fast degradation of CWAs. We found TiO 2 coatings deposited via atomic layer deposition (ALD) onto polyamide-6 nanofibers enable the formation of conformal Zr-based MOF thin films including UiO-66, UiO-66-NH 2 , and UiO-67. Cross-sectional TEM images show that these MOF crystals nucleate and grow directly on and around the nanofibers, with strong attachment to the substrates. These MOF-functionalized nanofibers exhibit excellent reactivity for detoxifying CWAs. The half-lives of a CWA simulant compound and nerve agent soman (GD) are as short as 7.3 min and 2.3 min, respectively. These results therefore provide the earliest report of MOF-nanofiber textile composites capable of ultra-fast degradation of CWAs. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chemical carcinogenic and mutagenic agents in the workplace, Poland, 2008–2010

Directory of Open Access Journals (Sweden)

Katarzyna Konieczko

2013-04-01

Full Text Available Background: The aim of this paper is to present a concise but comprehensive information on the occurrence of carcinogenic or mutagenic agents in Polish enterprises and the number of workers exposed to those agents reported to the central register by employers. Objectives and responsibilities of the register, as well as the range and methods of data gathering are discussed. Material and Methods: Data concerning carcinogenic or mutagenic chemical substances and technological processes reported to central register in 2008-2010 were analyzed. Results: In 2008-2010 more than 300 carcinogenic or mutagenic chemical substances were reported to the register. Approximately 2500 plants reported above 150 000 per-person-exposures annually. Among all technological processes regarded as occupational carcinogens, hardwood dusts exposure (about 660 companies; 11 000-13 000 exposed workers each year and exposure to polycyclic aromatic hydrocarbons (PAHs present in coal products (117-125 plantsl 3000 exposed per year were reported. Conclusions: The most widespread carcinogenic/mutagenic substances were: benzene, chromium(VI compounds: potassium dichromate and chromate, chromium(VI trioxide and other chromium compounds, ethylene oxide, asbestos, benzo[a]pyrene and gasoline. The highest number of men was exposed to particular PAHs and benzene , and the majority of women was exposed to benzene, potassium dichromate and chromate, acrylamide, ethylene oxide and gasoline. The lack of clear-cut definitione of occupational exposure to carcinogen creates a problem faced by employers in defining the accurate number of exposed workers. Med Pr 2013;64(2:181–192

Solid phase microextraction headspace sampling of chemical warfare agent contaminated samples : method development for GC-MS analysis

Energy Technology Data Exchange (ETDEWEB)

Jackson Lepage, C.R.; Hancock, J.R. [Defence Research and Development Canada, Medicine Hat, AB (Canada); Wyatt, H.D.M. [Regina Univ., SK (Canada)

2004-07-01

Defence R and D Canada-Suffield (DRDC-Suffield) is responsible for analyzing samples that are suspected to contain chemical warfare agents, either collected by the Canadian Forces or by first-responders in the event of a terrorist attack in Canada. The analytical techniques used to identify the composition of the samples include gas chromatography-mass spectrometry (GC-MS), liquid chromatography-mass spectrometry (LC-MS), Fourier-transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance spectroscopy. GC-MS and LC-MS generally require solvent extraction and reconcentration, thereby increasing sample handling. The authors examined analytical techniques which reduce or eliminate sample manipulation. In particular, this paper presented a screening method based on solid phase microextraction (SPME) headspace sampling and GC-MS analysis for chemical warfare agents such as mustard, sarin, soman, and cyclohexyl methylphosphonofluoridate in contaminated soil samples. SPME is a method which uses small adsorbent polymer coated silica fibers that trap vaporous or liquid analytes for GC or LC analysis. Collection efficiency can be increased by adjusting sampling time and temperature. This method was tested on two real-world samples, one from excavated chemical munitions and the second from a caustic decontamination mixture. 7 refs., 2 tabs., 3 figs.

Environmental fate and behaviour of the biocontrol agent Bacillus amyloliquefaciens CPA-8 after preharvest application to stone fruit.

Science.gov (United States)

Vilanova, Laura; Teixidó, Neus; Usall, Josep; Balsells-Llauradó, Marta; Gotor-Vila, Amparo; Torres, Rosario

2018-02-01

Bacillus amyloliquefaciens strain CPA-8 has been described as an effective biocontrol agent to control brown rot in stone fruit for both preharvest and postharvest applications. However, no information about the environmental fate and behaviour of this strain under field conditions is available. The dispersion of the CPA-8 application was evaluated using water-sensitive papers, and complete coverage was observed on the leaves of treated trees, while treatment. On non-treated trees, CPA-8 was detected on leaves until 180 days after treatment, and on weeds, the CPA-8 population was dependent on the distance from the treated trees. A high persistence of CPA-8 was detected on inert materials, such as clothes and gloves worn by handlers and plastic harvesting boxes. More than 99% of the samples with a CPA-8 phenotype were confirmed as CPA-8 using polymerase chain reaction (PCR). This work demonstrated a good distribution, persistence and adaptation of the CPA-8 strain to field and postharvest conditions. Monitoring of dispersion and persistence is an excellent tool to determine the time of application and provides valuable information for registering issues. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Complexing agents and pH influence on chemical durability of type I moulded glass containers.

Science.gov (United States)

Biavati, Alberto; Poncini, Michele; Ferrarini, Arianna; Favaro, Nicola; Scarpa, Martina; Vallotto, Marta

2017-06-16

Among the factors that affect the glass surface chemical durability, pH and complexing agents presence in aqueous solution have the main role (1). Glass surface attack can be also related to the delamination issue with glass particles appearance in the pharmaceutical preparation. A few methods to check for glass containers delamination propensity and some control guidelines have been proposed (2,3). The present study emphasizes the possible synergy between a few complexing agents with pH on the borosilicate glass chemical durability. Hydrolytic attack was performed in small volume 23 ml type I glass containers autoclaved according to EP or USP for 1 hour at 121°C, in order to enhance the chemical attack due to time, temperature and the unfavourable surface/volume ratio. 0,048 M or 0.024 M (moles/liter) solutions of the acids citric, glutaric, acetic, EDTA (ethylenediaminetetraacetic acid) and sodium phosphate with water for comparison, were used for the trials. The pH was adjusted ± 0,05 units at fixed values 5,5-6,6-7-7,4-8-9 by LiOH diluted solution. Since silicon is the main glass network former, silicon release into the attack solutions was chosen as the main index of the glass surface attack and analysed by ICPAES. The work was completed by the analysis of the silicon release in the worst attack conditions, of moulded glass, soda lime type II and tubing borosilicate glass vials to compare different glass compositions and forming technologies. Surface analysis by SEM was finally performed to check for the surface status after the worst chemical attack condition by citric acid. Copyright © 2017, Parenteral Drug Association.

Emergency management of chemical weapons injuries.

Science.gov (United States)

Anderson, Peter D

2012-02-01

The potential for chemical weapons to be used in terrorism is a real possibility. Classes of chemical weapons include nerve agents, vesicants (blister agents), choking agents, incapacitating agents, riot control agents, blood agents, and toxic industrial chemicals. The nerve agents work by blocking the actions of acetylcholinesterase leading to a cholinergic syndrome. Nerve agents include sarin, tabun, VX, cyclosarin, and soman. The vesicants include sulfur mustard and lewisite. The vesicants produce blisters and also damage the upper airways. Choking agents include phosgene and chlorine gas. Choking agents cause pulmonary edema. Incapacitating agents include fentanyl and its derivatives and adamsite. Riot control agents include Mace and pepper spray. Blood agents include cyanide. The mechanism of toxicity for cyanide is blocking oxidative phosphorylation. Toxic industrial chemicals include agents such as formaldehyde, hydrofluoric acid, and ammonia.

Persistent local chemical bonds in intermetallic phase formation

Energy Technology Data Exchange (ETDEWEB)

Bai, Yanwen [Key Laboratory for Liquid–Solid Structural Evolution and Processing of Materials, Ministry of Education, Shandong University, Jinan 250061 (China); Bian, Xiufang, E-mail: xfbian@sdu.edu.cn [Key Laboratory for Liquid–Solid Structural Evolution and Processing of Materials, Ministry of Education, Shandong University, Jinan 250061 (China); Qin, Xubo [Key Laboratory for Liquid–Solid Structural Evolution and Processing of Materials, Ministry of Education, Shandong University, Jinan 250061 (China); Zhang, Shuo; Huang, Yuying [Shanghai Synchrotron Radiation Facilities, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204 (China)

2014-05-01

We found a direct evidence for the existence of the local chemical Bi–In bonds in the BiIn{sub 2} melt. These bonds are strong and prevail, dominating the structure evolution of the intermetallic clusters. From the local structure of the melt-quenched BiIn{sub 2} ribbon, the chemical Bi–In bonds strengthen compared with those in the equilibrium solidified alloy. The chemical bonds in BiIn{sub 2} melt retain to solid during a rapid quenching process. The results suggest that the intermetallic clusters in the melt evolve into the as-quenched intermetallic phase, and the intermetallic phase originates from the chemical bonds between unlike atoms in the melt. The chemical bonds preserve the chemical ordered clusters and dominate the clusters evolution.

On-bead combinatorial synthesis and imaging of chemical exchange saturation transfer magnetic resonance imaging agents to identify factors that influence water exchange.

Science.gov (United States)

Napolitano, Roberta; Soesbe, Todd C; De León-Rodríguez, Luis M; Sherry, A Dean; Udugamasooriya, D Gomika

2011-08-24

The sensitivity of magnetic resonance imaging (MRI) contrast agents is highly dependent on the rate of water exchange between the inner sphere of a paramagnetic ion and bulk water. Normally, identifying a paramagnetic complex that has optimal water exchange kinetics is done by synthesizing and testing one compound at a time. We report here a rapid, economical on-bead combinatorial synthesis of a library of imaging agents. Eighty different 1,4,7,10-tetraazacyclododecan-1,4,7,10-tetraacetic acid (DOTA)-tetraamide peptoid derivatives were prepared on beads using a variety of charged, uncharged but polar, hydrophobic, and variably sized primary amines. A single chemical exchange saturation transfer image of the on-bead library easily distinguished those compounds having the most favorable water exchange kinetics. This combinatorial approach will allow rapid screening of libraries of imaging agents to identify the chemical characteristics of a ligand that yield the most sensitive imaging agents. This technique could be automated and readily adapted to other types of MRI or magnetic resonance/positron emission tomography agents as well.

The preventive Control of White Root Rot Disease in Small Holder Rubber Plantation Using Botanical, Biological and Chemical Agents

Directory of Open Access Journals (Sweden)

Joko Prasetyo

2014-03-01

Full Text Available The preventive control of white root rot disease in small holder plantation using botanical, biological, and chemical agents. A field and laboratory experiment were conducted from June 2008 to December 2009 in Panumangan, Tulang Bawang - Lampung. The  field experiment was intended to evaluate the effect of  botanical plants (Alpinia galanga, Sansiviera auranthii, and Marantha arundinacea, biological agents (organic matter and Trichoderma spp., and chemical agents (lime and natural sulphur on the incidence of white root rot disease and population of some soil microbes. The laboratory experiment was conducted  to observe the mechanism of botanical agents  in controlling white root rot disease. In the field experiment, the treatments were applied  in the experimental plot with cassava plant infection as the indicator. The variables  examined were the incidence of  white root rot and population of soil microbes. In the laboratory experiment, culture of R. microporus was grown in PDA containing root exudate of the antagonistic plant (botanical agent. The variable examined was colony diameter of R. microporus growing in the PDA plates. The results of the  field experiment  showed that planting of the botanical agents, and application of Trichoderma spp., as well as natural sulphur, decreased the incidence of white root rot disease. The effectiveness of M. arundinacea and Trichoderma spp. was comparable to natural  sulphur. The laboratory experiment showed only root exudate of  A. galanga and  S. auranthii that were significantly inhibit the growth of R. microporus.

Disposal of chemical agents and munitions stored at Umatilla Depot Activity, Hermiston, Oregon. Final Phase 1 environmental report

Energy Technology Data Exchange (ETDEWEB)

Zimmerman, G.P.; Hillsman, E.L.; Johnson, R.O.; Miller, R.L.; Patton, T.G.; Schoepfle, G.M.; Tolbert, V.R.; Feldman, D.L.; Hunsaker, D.B. Jr.; Kroodsma, R.L.; Morrissey, J.; Rickert, L.W.; Staub, W.P.; West, D.C.

1993-02-01

The Umatilla Depot Activity (UMDA) near Hermiston, Oregon, is one of eight US Army installations in the continental United States where lethal unitary chemical agents and munitions are stored, and where destruction of agents and munitions is proposed under the Chemical Stockpile Disposal Program (CSDP). The chemical agent inventory at UMDA consists of 11.6%, by weight, of the total US stockpile. The destruction of the stockpile is necessary to eliminate the risk to the public from continued storage and to dispose of obsolete and leaking munitions. In 1988 the US Army issued a Final Programmatic Environmental Impact Statement (FPEIS) for the CSDP that identified on-site disposal of agents and munitions as the environmentally preferred alternative (i.e., the alternative with the least potential to cause significant adverse impacts), using a method based on five measures of risk for potential human health and ecosystem/environmental effects; the effectiveness and adequacy of emergency preparedness capabilities also played a key role in the FPEIS selection methodology. In some instances, the FPEIS included generic data and assumptions that were developed to allow a consistent comparison of potential impacts among programmatic alternatives and did not include detailed conditions at each of the eight installations. The purpose of this Phase 1 report is to examine the proposed implementation of on-site disposal at UMDA in light of more recent and more detailed data than those included in the FPEIS. Specifically, this Phase 1 report is intended to either confirm or reject the validity of on-site disposal for the UMDA stockpile. Using the same computation methods as in the FPEIS, new population data were used to compute potential fatalities from hypothetical disposal accidents. Results indicate that onsite disposal is clearly preferable to either continued storage at UMDA or transportation of the UMDA stockpile to another depot for disposal.

Network flow of mobile agents enhances the evolution of cooperation

Science.gov (United States)

Ichinose, G.; Satotani, Y.; Nagatani, T.

2018-01-01

We study the effect of contingent movement on the persistence of cooperation on complex networks with empty nodes. Each agent plays the Prisoner's Dilemma game with its neighbors and then it either updates the strategy depending on the payoff difference with neighbors or it moves to another empty node if not satisfied with its own payoff. If no neighboring node is empty, each agent stays at the same site. By extensive evolutionary simulations, we show that the medium density of agents enhances cooperation where the network flow of mobile agents is also medium. Moreover, if the movements of agents are more frequent than the strategy updating, cooperation is further promoted. In scale-free networks, the optimal density for cooperation is lower than other networks because agents get stuck at hubs. Our study suggests that keeping a smooth network flow is significant for the persistence of cooperation in ever-changing societies.

Non-persistent pesticides removal in constructed wetlands

Science.gov (United States)

Tu, Yue; Jiang, Lei; Li, Haixiang

2018-03-01

The heavy use of non-persistent pesticides, resulting in the accumulation of environment and destroy the aquatic environment. This paper presents the research status of using CWs to treat non-persistent pesticides in water. The removal mechanisms are mainly physical deposition, chemical hydrolysis and plant absorption. Analysis of the factors that affect the removal effect are mainly the nature of pesticides, HRT, plants. Some scholars have proposed that secondary products of non-persistent pesticides may be more harmful to the environment, However, the relevant reports are scarce.

Treatment of chemical warfare agents by zero-valent iron nanoparticles and ferrate(VI)/(III) composite

International Nuclear Information System (INIS)

Zboril, Radek; Andrle, Marek; Oplustil, Frantisek; Machala, Libor; Tucek, Jiri; Filip, Jan; Marusak, Zdenek; Sharma, Virender K.

2012-01-01

Highlights: ► Ferrate(VI) has been found to be highly efficient to decontaminate chemical warfare agents. ► Fast degradation of sulfur mustard, soman and compound VX by ferrate(VI). ► Nanoscale zero-valent iron particles are considerably less efficient in degradation of studied warfare agents compared to ferrate(VI). - Abstract: Nanoscale zero-valent iron (nZVI) particles and a composite containing a mixture of ferrate(VI) and ferrate(III) were prepared by thermal procedures. The phase compositions, valence states of iron, and particle sizes of iron-bearing compounds were determined by combination of X-ray powder diffraction, Mössbauer spectroscopy and scanning electron microscopy. The applicability of these environmentally friendly iron based materials in treatment of chemical warfare agents (CWAs) has been tested with three representative compounds, sulfur mustard (bis(2-chlorethyl) sulfide, HD), soman ((3,3′-imethylbutan-2-yl)-methylphosphonofluoridate, GD), and O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothiolate (VX). Zero-valent iron, even in the nanodimensional state, had a sluggish reactivity with CWAs, which was also observed in low degrees of CWAs degradation. On the contrary, ferrate(VI)/(III) composite exhibited a high reactivity and complete degradations of CWAs were accomplished. Under the studied conditions, the estimated first-order rate constants (∼10 −2 s −1 ) with the ferrate(VI)/(III) composite were several orders of magnitude higher than those of spontaneous hydrolysis of CWAs (10 −8 –10 −6 s −1 ). The results demonstrated that the oxidative technology based on application of ferrate(VI) is very promising to decontaminate CWAs.

[Synthesis and physico-chemical properties of lonazolac-Ca, a new antiphlogistic/antirheumatic agent].

Science.gov (United States)

Rainer, G; Krüger, U; Klemm, K

1981-01-01

Calcium-[3-(p-chlorophenyl)-1-phenylpyrazole-4]-acetate (Lonazolac-Ca, active principle of Irritren) is a new antiinflammatory/antirheumatic agent whose synthesis and physico-chemical properties are described. The physical parameters measured (pKa, partition coefficient P, saturation concentration Cs, surface activity, protein binding) are held against the corresponding values of indomethacin, diclofenac, and phenylbutazone. The size of the permeability coefficient PM of the passive transport through artificial phospholipid collodion membranes as well as the invasion curves calculated from PM indicate a good absorption of lonazolac in man.

Preliminary screening of alternative technologies to incineration for treatment of chemical-agent-contaminated soil, Rocky Mountain Arsenal

Energy Technology Data Exchange (ETDEWEB)

Shem, L.M.; Rosenblatt, D.H.; Smits, M.P.; Wilkey, P.L.; Ballou, S.W.

1995-12-01

In support of the U.S. Army`s efforts to determine the best technologies for remediation of soils, water, and structures contaminated with pesticides and chemical agents, Argonne National Laboratory has reviewed technologies for treating soils contaminated with mustard, lewisite, sarin, o-ethyl s-(2- (diisopropylamino)ethyl)methyl-phosphonothioate (VX), and their breakdown products. This report focuses on assessing alternatives to incineration for dealing with these contaminants. For each technology, a brief description is provided, its suitability and constraints on its use are identified, and its overall applicability for treating the agents of concern is summarized. Technologies that merit further investigation are identified.

Hyperthyroidism as a cause of persistent vomiting.

NARCIS (Netherlands)

Hoogendoorn, E.H.; Cools, B.M.

2004-01-01

A 32-year-old woman presented with persistent vomiting, epigastric pain and weight loss. A sinus tachycardia was the clue to the diagnosis of hyperthyroidism due to Graves' disease. On treatment with propylthiouracil and a beta-blocking agent, her symptoms resolved within one day, even though her

Effect of different complexing agents on the properties of chemical-bath-deposited ZnS thin films

Energy Technology Data Exchange (ETDEWEB)

Liu, Jun; Wei, Aixiang, E-mail: weiax@gdut.edu.cn; Zhao, Yu

2014-03-05

Highlights: • To fabricate high quality ZnS films need to promote the ion-by-ion process and restrain cluster-by-cluster process. • The complexation ability of tri-sodium citrate is stronger than that of hydrazine hydrate. • The nucleation density of nuclei determine the performance of ZnS thin films. -- Abstract: Zinc sulfide (ZnS) thin films were deposited on glass substrates using the chemical bath deposition (CBD) technique. The effects of different complexing agents (tri-sodium citrate, hydrazine hydrate) and their concentrations on the structure, composition, morphology, optical properties and growth mechanism of ZnS thin films were investigated. The results indicated that the chemical-bath-deposited ZnS thin films exhibit poor crystallinity and a high Zn/S atomic ratio with an average transmittance of 75% in the range of visible light. The ZnS thin films prepared using hydrazine hydrate as the complexing agent present a more compact surface, a smaller average particle size, and a sharper absorption edge at 300–340 nm compared with those prepared using tri-sodium citrate. Based on our experimental observations and analysis, we conclude that the predominant growth mechanism of ZnS thin films is an ion-by-ion process. The nucleation density of Zn(OH){sub 2} nuclei on the substrate in the initial stage produces the different morphologies and properties of the ZnS thin films prepared using the two complexing agents.

Chemical Agent Data Sheets. Volume 1

Science.gov (United States)

1974-12-01

petechial hemorrhage with discoloration; I edema with extension of the swelling, necrosis and ultimately dry gangrene; ulceration and eventually...vomiting, depression, and fever , and are far more prone to occur iii hot than in temperate climates. halaise and nausea generally are the first...productive. Fever , dyspnea, and moist rales may develop. The incidence of bronchopneurnonia is high. Convalescence is slow and cough may persist a

Decontamination of radiological agents from drinking water infrastructure: a literature review and summary.

Science.gov (United States)

Szabo, Jeff; Minamyer, Scott

2014-11-01

This report summarizes the current state of knowledge on the persistence of radiological agents on drinking water infrastructure (such as pipes) along with information on decontamination should persistence occur. Decontamination options for drinking water infrastructure have been explored for some important radiological agents (cesium, strontium and cobalt), but important data gaps remain. Although some targeted experiments have been published on cesium, strontium and cobalt persistence on drinking water infrastructure, most of the data comes from nuclear clean-up sites. Furthermore, the studies focused on drinking water systems use non-radioactive surrogates. Non-radioactive cobalt was shown to be persistent on iron due to oxidation with free chlorine in drinking water and precipitation on the iron surface. Decontamination with acidification was an effective removal method. Strontium persistence on iron was transient in tap water, but adherence to cement-mortar has been demonstrated and should be further explored. Cesium persistence on iron water infrastructure was observed when flow was stagnant, but not with water flow present. Future research suggestions focus on expanding the available cesium, strontium and cobalt persistence data to other common infrastructure materials, specifically cement-mortar. Further exploration chelating agents and low pH treatment is recommended for future decontamination studies. Published by Elsevier Ltd.

Persistent toxic substances: sources, fates and effects.

Science.gov (United States)

Wong, Ming H; Armour, Margaret-Ann; Naidu, Ravi; Man, Ming

2012-01-01

Persistent toxic substances (PTS) include the Stockholm persistent organic pollutants, like dichlorodiphenyltrichloroethane, polychlorinated biphenyls, dioxin/furan, etc., and organometallic compounds, like organomercury, organotin, and organolead, which all share the same characteristics of being persistent, toxic, bioaccumulative, and able to travel long distances through different media. The adverse health effects of some of the emerging chemicals like pentabromodiphenyl ether, bisphenol A, and di(2-ethylhexyl)phthalate, which are widely used in daily appliances (e.g., TVs, computers, mobile phones, plastic baby bottles), have become a public health concern due to more evidence now available showing their adverse effects like disturbance of the endocrine system and cancer. This article is an attempt to review the current status of PTS in our environment, citing case studies in China and North America, and whether our existing drinking water treatment and wastewater treatment processes are adequate in removing them from water. Some management issues of these emerging chemicals of concern are also discussed.

Crucial steps to life: From chemical reactions to code using agents.

Science.gov (United States)

Witzany, Guenther

2016-02-01

The concepts of the origin of the genetic code and the definitions of life changed dramatically after the RNA world hypothesis. Main narratives in molecular biology and genetics such as the "central dogma," "one gene one protein" and "non-coding DNA is junk" were falsified meanwhile. RNA moved from the transition intermediate molecule into centre stage. Additionally the abundance of empirical data concerning non-random genetic change operators such as the variety of mobile genetic elements, persistent viruses and defectives do not fit with the dominant narrative of error replication events (mutations) as being the main driving forces creating genetic novelty and diversity. The reductionistic and mechanistic views on physico-chemical properties of the genetic code are no longer convincing as appropriate descriptions of the abundance of non-random genetic content operators which are active in natural genetic engineering and natural genome editing. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Trace Detection of Organophosphorus Chemical Warfare Agents in Wastewater and Plants by Luminescent UIO-67(Hf) and Evaluating the Bioaccumulation of Organophosphorus Chemical Warfare Agents.

Science.gov (United States)

Lian, Xiao; Yan, Bing

2018-05-02

Organophosphorus chemical warfare agents (OPCWAs) are a group of organic pollutants characterized by high toxicity and chemical stability, and they are very difficult to be degraded. The trace quality of OPCWAs in water and food will cause great harm to the human body. Therefore, the detection of OPCWAs is a difficult challenge, which has become the research hotspot over the world. In this work, a Hf-based luminescent metal-organic framework (Eu@1) is prepared, and the reactivity of Hf 12 results in a methanephosphonic acid (MPA)-induced luminescence quenching and the charge transfer from MPA to Hf(IV) and generated exciplexes which are responsible for this quenching effect. The excellent performance of Eu@1 in the detection of MPA, with its finer selectivity, high sensitivity (LOD = 0.4 ppm), and large linear range (10 -7 to 10 -3 M), is encouraging for application in wastewater detection. Importantly, MPA is a pollutant that can be absorbed by plants and causes the bioaccumulation effect, and thus, the detection of MPA in real plant samples is a purposeful topic. Eu@1 also achieved satisfactory results in actual plant sample testing, and the bioaccumulation of MPA in onions, turnips, and cabbages is determined via our sensor. This fabricated detector provides a feasible path for the detection of ppm-level OPCWAs in a complex environment, which will help humans to avoid OPCWA-contaminated foods.

Treatment of chemical warfare agents by zero-valent iron nanoparticles and ferrate(VI)/(III) composite

Energy Technology Data Exchange (ETDEWEB)

Zboril, Radek, E-mail: zboril@prfnw.upol.cz [Regional Centre of Advanced Technologies and Materials, Departments of Physical Chemistry and Experimental Physics, 17. listopadu 1192/12, 771 46 Olomouc (Czech Republic); Andrle, Marek; Oplustil, Frantisek [Military Institute VOP-026 Sternberk, Division in Brno, Rybkova 8, 602 00 Brno (Czech Republic); Machala, Libor; Tucek, Jiri; Filip, Jan; Marusak, Zdenek [Regional Centre of Advanced Technologies and Materials, Departments of Physical Chemistry and Experimental Physics, 17. listopadu 1192/12, 771 46 Olomouc (Czech Republic); Sharma, Virender K., E-mail: vsharma@fit.edu [Chemistry Department, Florida Institute of Technology, 150 West University Boulevard, Melbourne, FL 32901 (United States); Center of Ferrate Excellence, Florida Institute of Technology, 150 West University Boulevard, Melbourne, FL 32901 (United States)

2012-04-15

Highlights: Black-Right-Pointing-Pointer Ferrate(VI) has been found to be highly efficient to decontaminate chemical warfare agents. Black-Right-Pointing-Pointer Fast degradation of sulfur mustard, soman and compound VX by ferrate(VI). Black-Right-Pointing-Pointer Nanoscale zero-valent iron particles are considerably less efficient in degradation of studied warfare agents compared to ferrate(VI). - Abstract: Nanoscale zero-valent iron (nZVI) particles and a composite containing a mixture of ferrate(VI) and ferrate(III) were prepared by thermal procedures. The phase compositions, valence states of iron, and particle sizes of iron-bearing compounds were determined by combination of X-ray powder diffraction, Moessbauer spectroscopy and scanning electron microscopy. The applicability of these environmentally friendly iron based materials in treatment of chemical warfare agents (CWAs) has been tested with three representative compounds, sulfur mustard (bis(2-chlorethyl) sulfide, HD), soman ((3,3 Prime -imethylbutan-2-yl)-methylphosphonofluoridate, GD), and O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothiolate (VX). Zero-valent iron, even in the nanodimensional state, had a sluggish reactivity with CWAs, which was also observed in low degrees of CWAs degradation. On the contrary, ferrate(VI)/(III) composite exhibited a high reactivity and complete degradations of CWAs were accomplished. Under the studied conditions, the estimated first-order rate constants ({approx}10{sup -2} s{sup -1}) with the ferrate(VI)/(III) composite were several orders of magnitude higher than those of spontaneous hydrolysis of CWAs (10{sup -8}-10{sup -6} s{sup -1}). The results demonstrated that the oxidative technology based on application of ferrate(VI) is very promising to decontaminate CWAs.

Teamwork in Multi-Agent Systems A Formal Approach

CERN Document Server

Dunin-Keplicz, Barbara Maria

2010-01-01

What makes teamwork tick?. Cooperation matters, in daily life and in complex applications. After all, many tasks need more than a single agent to be effectively performed. Therefore, teamwork rules!. Teams are social groups of agents dedicated to the fulfilment of particular persistent tasks. In modern multiagent environments, heterogeneous teams often consist of autonomous software agents, various types of robots and human beings. Teamwork in Multi-agent Systems: A Formal Approach explains teamwork rules in terms of agents' attitudes and their complex interplay. It provides the first comprehe

Effects of chemical and physical agents on recombination events in cells of the germ line of male and female Drosophila melanogaster.

Science.gov (United States)

Würgler, F E

1991-01-01

Genotoxic agents can induce mutations as well as recombination in the genetic material. The fruit fly Drosophila melanogaster was one of the first assay systems to test physical and chemical agents for recombinogenic effects. Such effects can be observed in cells of the germ line as well as in somatic cells. At present information is available on 54 agents, among them 48 chemicals that have been tested in cells of the germ line of males and/or females. Effects on meiotic recombination in female germ cells cannot simply be classified as positive or negative since for a number of agents, depending on the chromosome region studied, recombination frequencies may be increased, unaffected or decreased. The male germ line of D. melanogaster represents a unique situation because meiotic recombination does not occur. Among 25 agents tested in male germ cells 24 did induce male recombination, among them alkylating, intercalating and cross-linking agents, direct-acting ones as well as compounds needing metabolic activation. With several compounds the frequency of induced recombination is highest in the heterochromatic regions near the centromeres. In brood pattern analyses, e.g., after exposure of adult males to ionizing radiation, the first appearance of crossover progeny is indicative of the sampling of exposed spermatocytes. In premeiotic cells of the male and the female germ line mitotic recombination can occur. Upon clonal expansion of the recombinant cells, clusters of identical crossovers can be observed.

Structural characterization of chemical warfare agent degradation products in decontamination solutions with proton band-selective (1)H-(31)P NMR spectroscopy.

Science.gov (United States)

Koskela, Harri; Hakala, Ullastiina; Vanninen, Paula

2010-06-15

Decontamination solutions, which are usually composed of strong alkaline chemicals, are used for efficient detoxification of chemical warfare agents (CWAs). The analysis of CWA degradation products directly in decontamination solutions is challenging due to the nature of the matrix. Furthermore, occasionally an unforeseen degradation pathway can result in degradation products which could be eluded to in standard analyses. Here, we present the results of the application of proton band-selective (1)H-(31)P NMR spectroscopy, i.e., band-selective 1D (1)H-(31)P heteronuclear single quantum coherence (HSQC) and band-selective 2D (1)H-(31)P HSQC-total correlation spectroscopy (TOCSY), for ester side chain characterization of organophosphorus nerve agent degradation products in decontamination solutions. The viability of the approach is demonstrated with a test mixture of typical degradation products of nerve agents sarin, soman, and VX. The proton band-selective (1)H-(31)P NMR spectroscopy is also applied in characterization of unusual degradation products of VX in GDS 2000 solution.

A polarization system for persistent chemical detection

Science.gov (United States)

Craven-Jones, Julia; Appelhans, Leah; Couphos, Eric; Embree, Todd; Finnegan, Patrick; Goldstein, Dennis; Karelitz, David; LaCasse, Charles; Luk, Ting S.; Mahamat, Adoum; Massey, Lee; Tanbakuchi, Anthony; Washburn, Cody; Vigil, Steven

2015-09-01

We report on the development of a prototype polarization tag based system for detecting chemical vapors. The system primarily consists of two components, a chemically sensitive tag that experiences a change in its optical polarization properties when exposed to a specific chemical of interest, and an optical imaging polarimeter that is used to measure the polarization properties of the tags. Although the system concept could be extended to other chemicals, for the initial system prototype presented here the tags were developed to be sensitive to hydrogen fluoride (HF) vapors. HF is used in many industrial processes but is highly toxic and thus monitoring for its presence and concentration is often of interest for personnel and environmental safety. The tags are periodic multilayer structures that are produced using standard photolithographic processes. The polarimetric imager has been designed to measure the degree of linear polarization reflected from the tags in the short wave infrared. By monitoring the change in the reflected polarization signature from the tags, the polarimeter can be used to determine if the tag was exposed to HF gas. In this paper, a review of the system development effort and preliminary test results are presented and discussed, as well as our plan for future work.

Niobium(V) saponite clay for the catalytic oxidative abatement of chemical warfare agents.

Science.gov (United States)

Carniato, Fabio; Bisio, Chiara; Psaro, Rinaldo; Marchese, Leonardo; Guidotti, Matteo

2014-09-15

A Nb(V)-containing saponite clay was designed to selectively transform toxic organosulfur chemical warfare agents (CWAs) under extremely mild conditions into nontoxic products with reduced environmental impact. Thanks to the insertion of Nb(V) sites within the saponite framework, a bifunctional catalyst with strong oxidizing and acid properties was obtained. Remarkable activity and high selectivity were observed for the oxidative abatement of (2-chloroethyl)ethyl sulfide (CEES), a simulant of sulfur mustard, at room temperature with aqueous hydrogen peroxide. This performance was significantly better compared to a conventional commercial decontamination powder. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chromatography and mass spectrometry of chemical warfare agents, toxins and related compounds: state of the art and future prospects

NARCIS (Netherlands)

Kientz, C.E.

1998-01-01

Methods for the identification of chemical warfare agents, toxins, bioregulators and related products are frequently reported in literature. These methods are often based on instrumental analysis using chromatography (gas and liquid) and mass spectrometry. Here, these instrumental techniques are

Biasing hydrogen bond donating host systems towards chemical warfare agent recognition.

Science.gov (United States)

Hiscock, Jennifer R; Wells, Neil J; Ede, Jayne A; Gale, Philip A; Sambrook, Mark R

2016-10-12

A series of neutral ditopic and negatively charged, monotopic host molecules have been evaluated for their ability to bind chloride and dihydrogen phosphate anions, and neutral organophosphorus species dimethyl methylphosphonate (DMMP), pinacolyl methylphosphonate (PMP) and the chemical warfare agent (CWA) pinacolyl methylphosphonofluoridate (GD, soman) in organic solvent via hydrogen bonding. Urea, thiourea and boronic acid groups are shown to bind anions and neutral guests through the formation of hydrogen bonds, with the urea and thiourea groups typically exhibiting higher affinity interactions. The introduction of a negative charge on the host structure is shown to decrease anion affinity, whilst still allowing for high stability host-GD complex formation. Importantly, the affinity of the host for the neutral CWA GD is greater than for anionic guests, thus demonstrating the potential for selectivity reversal based on charge repulsion.

Disposal of chemical agents and munitions stored at Anniston Army Depot, Anniston, Alabama

Energy Technology Data Exchange (ETDEWEB)

Hunsaker, D.B. Jr.; Zimmerman, G.P.; Hillsman, E.L.; Miller, R.L.; Schoepfle, G.M.; Johnson, R.O.; Tolbert, V.R.; Kroodsma, R.L.; Rickert, L.W.; Rogers, G.O.; Staub, W.P.

1990-09-01

The purpose of this Phase I report is to examined the proposed implementation of on-site disposal at Anniston Army Depot (ANAD) in light of more detailed and more recent data than those included in the Final Programmatic Environmental Impact Statement (EPEIS). Two principal issues are addressed: (1) whether or not the new data would result in identification of on-site disposal at ANAD as the environmentally preferred alternative (using the same selection method and data analysis tools as in the FPEIS), and (2) whether or not the new data indicate the presence of significant environmental resources that could be affected by on-site disposal at ANAD. In addition, a status report is presented on the maturity of the disposal technology (and now it could affect on-site disposal at ANAD). Inclusion of these more recent data into the FPEIS decision method resulted in confirmation of on-site disposal for ANAD. No unique resources with the potential to prevent or delay implementation of on-site disposal at ANAD have been identified. A review of the technology status identified four principal technology developments that have occurred since publication of the FPEIS and should be of value in the implementation of on-site disposal at ANAD: the disposal of nonlethal agent at Pine Bluff Arsenal, located near Pine Bluff, Arkansas; construction and testing of facilities for disposal of stored lethal agent at Johnston Atoll, located about 1300 km (800 miles) southwest of Hawaii in the Pacific Ocean; lethal agent disposal tests at the chemical agent pilot plant operations at Tooele Army Depot, located near Salt Lake City, Utah; and equipment advances. 18 references, 13 figs., 10 tabs.

Sulfomethylated lignosulfonates as additives in oil recovery processes involving chemical recovery agents

Energy Technology Data Exchange (ETDEWEB)

Kalfoglou, G.

1979-10-30

A process for producing petroleum from subterranean formations is disclosed wherein production from the formation is obtained by driving a fluid from an injection well to a production well. The process involves injecting via the injection well into the formation an aqueous solution of sulfomethylated lignosulfonate salt as a sacrificial agent to inhibit the deposition of surfactant and/or polymer on the reservoir matrix. The process may best be carried out by injecting the sulfomethylated lignosulfonates into the formation through the injection well mixed with either a polymer, a surfactant solution and/or a micellar dispersion. This mixture would then be followed by a drive fluid such as water to push the chemicals to the production well.

Sulfomethylated lignosulfonates as additives in oil recovery processes involving chemical recovery agents

Energy Technology Data Exchange (ETDEWEB)

Kalfoglou, G.

1981-05-26

A process for producing petroleum from subterranean formations is disclosed wherein production from the formation is obtained by driving a fluid from an injection well to a production well. The process involves injecting via the injection well into the formation an aqueous solution of sulfomethylated lignosulfonate salt as a sacrificial agent to inhibit the deposition of surfactant and/or polymer on the reservoir matrix. The process may best be carried out by injecting the sulfomethylated lignosulfonates into the formation through the injection well mixed with either a polymer, a surfactant solution and/or a micellar dispersion. This mixture would then be followed by a drive fluid such as water to push the chemicals to the production well.

Legionella pneumophila: the paradox of a highly sensitive opportunistic waterborne pathogen able to persist in the environment

Directory of Open Access Journals (Sweden)

Jean-Marc eBerjeaud

2016-04-01

Full Text Available Legionella pneumophila, the major causative agent of Legionnaires’ disease, is found in freshwater environments in close association with free-living amoebae and multispecies biofilms, leading to persistence, spread, biocide resistance, and elevated virulence of the bacterium. Indeed, legionellosis outbreaks are mainly due to the ability of this bacterium to colonize and persist in water facilities, despite harsh physical and chemical treatments. However, these treatments are not totally efficient and, after a lag period, L. pneumophila may be able to quickly re-colonize these systems. Several natural compounds (biosurfactants, antimicrobial peptides… with anti-Legionella properties have recently been described in the literature, highlighting their specific activities against this pathogen. In this review, we first consider this hallmark of Legionella to resist killing, in regard to its biofilm or host-associated life style. Then, we focus more accurately on natural anti-Legionella molecules described so far, which could provide new eco-friendly and alternative ways to struggle against this important pathogen in plumbing.

HIGHLY SELECTIVE SENSORS FOR CHEMICAL AND BIOLOGICAL WARFARE AGENTS, INSECTICIDES AND VOCS BASED ON A MOLECULAR SURFACE IMPRINTING TECHNIQUE

Science.gov (United States)

Abstract was given as an oral platform presentation at the Pittsburgh Conference, Orlando FL (March 5-9, 2006). Research described is the development of sensors based on molecular surface imprinting. Applications include the monitoring of chemical and biological agents and inse...

The influence of water disposal method on the property of chemical oil-displacement agent--taking Guan 109-1 area of Dagang oilfield as example

Directory of Open Access Journals (Sweden)

Shengwang Yuan

2018-03-01

Full Text Available Aiming at the actual demand of Guan 109-1 block in Dagang oilfield, by means of instrumental analysis, chemical analysis, modern physical simulation, viewing polymer viscosity and seepage characteristic as evaluation index, the experimental research on the influence of water disposal method on the property of chemical oil-displacement agent was carried out. Results showed that through adding scaling agent, scale was formed because of the reaction between scaling agent and Ca2+, Mg2+ in the flooding water, which could enhance the viscosity of polymer solution. Through comparing the resistance factor and residual resistance factor of polymer solution which was respectively prepared with flooding water, softened water and scale, the resistance factor and residual resistance factor of polymer solution with scale was the largest, that of polymer solution prepared with softened water was second and that of polymer solution prepared with flooding water came last. Furthermore, scaling agent weakened the gelling effect between cross-linking agent Cr3+ and polymer molecule chains. The earlier the cross-linking agent Cr3+ was added, the larger the polymer viscosity, resistance factor and residual resistance factor of Cr3+ polymer were.

Agents Within our Midst

Science.gov (United States)

2012-03-14

agents; and the development of bio -monitoring protocols for civilian and service personnel during a chemical attack. These efforts have resulted in greater...produced by staphylococcal bacteria that is and is classified as a CDC select agent which has the potential to be used as a biological weapon .1...NMR chemical shift perturbation titrations with Fab (fragment, antigen binding regions) domains of 20B1, 14G8, and 6D3 using deuterated (2H) SEB

Marine toxicity and persistence of surfactants used in the petroleum producing industry

International Nuclear Information System (INIS)

Maddin, C.M.

1991-01-01

This paper presents a survey of marine toxicity and biodegradability data for surfactants used in the petroleum industry. Surfactants are key chemicals in the formulation of products such as emulsifiers, demulsifiers, dispersants and inhibitors. They are also used directly as foaming and defoaming agents. Because they function at low concentrations, below 1%, and have a tendency to adsorb on solid surfaces, their long-term environmental effects are minimal. In applications such as cementing, surfactants cannot migrate into the environment and, thus, have no bioavailability. The possibility of environmental contamination has caused well operators and regulatory agencies to require fish toxicity and persistence data for products used in servicing wells. This data has been organized for nonionic, anionic, cationic and amphoteric surfactants. Nonionic surfactants are toxic to fish at concentrations below 10 mg/L to over 2500 mg/L depending on their chemical compositions. Anionic surfactants are toxic to fish at concentrations under 1 mg/L to several hundred mg/L depending on their chemical compositions. cationic and amphoteric surfactants are generally toxic to fish at concentrations below 50 mg/L. Overall efforts are aimed at low toxicity and high biodegradability with the least compromise in product efficiency. This requires the continual testing and environmental evaluation of surfactants summarized herein

Potential of Biological Agents in Decontamination of Agricultural Soil

Directory of Open Access Journals (Sweden)

Muhammad Kashif Javaid

2016-01-01

Full Text Available Pesticides are widely used for the control of weeds, diseases, and pests of cultivated plants all over the world, mainly since the period after the Second World War. The use of pesticides is very extensive to control harm of pests all over the globe. Persistent nature of most of the synthetic pesticides causes serious environmental concerns. Decontamination of these hazardous chemicals is very essential. This review paper elaborates the potential of various biological agents in decontamination of agricultural soils. The agricultural crop fields are contaminated by the periodic applications of pesticides. Biodegradation is an ecofriendly, cost-effective, highly efficient approach compared to the physical and chemical methods which are expensive as well as unfriendly towards environment. Biodegradation is sensitive to the concentration levels of hydrogen peroxide and nitrogen along with microbial community, temperature, and pH changes. Experimental work for optimum conditions at lab scale can provide very fruitful results about specific bacterial, fungal strains. This study revealed an upper hand of bioremediation over physicochemical approaches. Further studies should be carried out to understand mechanisms of biotransformation.

Potential of Biological Agents in Decontamination of Agricultural Soil.

Science.gov (United States)

Javaid, Muhammad Kashif; Ashiq, Mehrban; Tahir, Muhammad

2016-01-01

Pesticides are widely used for the control of weeds, diseases, and pests of cultivated plants all over the world, mainly since the period after the Second World War. The use of pesticides is very extensive to control harm of pests all over the globe. Persistent nature of most of the synthetic pesticides causes serious environmental concerns. Decontamination of these hazardous chemicals is very essential. This review paper elaborates the potential of various biological agents in decontamination of agricultural soils. The agricultural crop fields are contaminated by the periodic applications of pesticides. Biodegradation is an ecofriendly, cost-effective, highly efficient approach compared to the physical and chemical methods which are expensive as well as unfriendly towards environment. Biodegradation is sensitive to the concentration levels of hydrogen peroxide and nitrogen along with microbial community, temperature, and pH changes. Experimental work for optimum conditions at lab scale can provide very fruitful results about specific bacterial, fungal strains. This study revealed an upper hand of bioremediation over physicochemical approaches. Further studies should be carried out to understand mechanisms of biotransformation.

Decontamination of chemical and biological warfare agents with a single multi-functional material.

Science.gov (United States)

Amitai, Gabi; Murata, Hironobu; Andersen, Jill D; Koepsel, Richard R; Russell, Alan J

2010-05-01

We report the synthesis of new polymers based on a dimethylacrylamide-methacrylate (DMAA-MA) co-polymer backbone that support both chemical and biological agent decontamination. Polyurethanes containing the redox enzymes glucose oxidase and horseradish peroxidase can convert halide ions into active halogens and exert striking bactericidal activity against gram positive and gram negative bacteria. New materials combining those biopolymers with a family of N-alkyl 4-pyridinium aldoxime (4-PAM) halide-acrylate co-polymers offer both nucleophilic activity for the detoxification of organophosphorus nerve agents and internal sources of halide ions for generation of biocidal activity. Generation of free bromine and iodine was observed in the combined material resulting in bactericidal activity of the enzymatically formed free halogens that caused complete kill of E. coli (>6 log units reduction) within 1 h at 37 degrees C. Detoxification of diisopropylfluorophosphate (DFP) by the polyDMAA MA-4-PAM iodide component was dose-dependent reaching 85% within 30 min. A subset of 4-PAM-halide co-polymers was designed to serve as a controlled release reservoir for N-hydroxyethyl 4-PAM (HE 4-PAM) molecules that reactivate nerve agent-inhibited acetylcholinesterase (AChE). Release rates for HE 4-PAM were consistent with hydrolysis of the HE 4-PAM from the polymer backbone. The HE 4-PAM that was released from the polymer reactivated DFP-inhibited AChE at a similar rate to the oxime antidote 4-PAM. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Metal-Organic Framework Modified Glass Substrate for Analysis of Highly Volatile Chemical Warfare Agents by Paper Spray Mass Spectrometry.

Science.gov (United States)

Dhummakupt, Elizabeth S; Carmany, Daniel O; Mach, Phillip M; Tovar, Trenton M; Ploskonka, Ann M; Demond, Paul S; DeCoste, Jared B; Glaros, Trevor

2018-03-07

Paper spray mass spectrometry has been shown to successfully analyze chemical warfare agent (CWA) simulants. However, due to the volatility differences between the simulants and real G-series (i.e., sarin, soman) CWAs, analysis from an untreated paper substrate proved difficult. To extend the analytical lifetime of these G-agents, metal-organic frameworks (MOFs) were successfully integrated onto the paper spray substrates to increase adsorption and desorption. In this study, several MOFs and nanoparticles were tested to extend the analytical lifetimes of sarin, soman, and cyclosarin on paper spray substrates. It was found that the addition of either UiO-66 or HKUST-1 to the paper substrate increased the analytical lifetime of the G-agents from less than 5 min detectability to at least 50 min.

How synergistic or antagonistic effects may influence the mutual hazard ranking of chemicals

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Lars Carlsen

2015-04-01

Full Text Available The presence of various agents, including humic materials, nanomaterials, microplastics, or simply specific chemical compounds, may cause changes in the apparent persistence, bioaccumulation, and/or toxicity (PBT of a chemical compound leading to an either increased or decreased PBT characteristics and thus an increased or decreased hazard evaluation. In the present paper, a series chloro-containing obsolete pesticides is studied as an illustrative example. Partial order methodology is used to quantify how changed P, B, or T characteristics of methoxychlor (MEC influences the measure of the hazard of MEC, relative to the other 11 compounds in the series investigated. Not surprisingly, an increase in one of the three indicators (P, B, or T lead to an increased average order and thus an increased relative hazard as a result of a synergistic effect. A decrease in one of the indicator values analogously causes a decreased average order/relative hazard through an antagonistic effect; the effect, however, being less pronounced. It is further seen that the effect of changing the apparent value of the three indicators is different. Thus, persistence apparently is more important that bioaccumulation which again appears more important than toxicity, which is in agreement with previous work. The results are discussed with reference to the European chemicals framework on registration, evaluation and authorization of chemicals (REACH framework.

Ion mobility spectrometric analysis of vaporous chemical warfare agents by the instrument with corona discharge ionization ammonia dopant ambient temperature operation.

Science.gov (United States)

Satoh, Takafumi; Kishi, Shintaro; Nagashima, Hisayuki; Tachikawa, Masumi; Kanamori-Kataoka, Mieko; Nakagawa, Takao; Kitagawa, Nobuyoshi; Tokita, Kenichi; Yamamoto, Soichiro; Seto, Yasuo

2015-03-20

The ion mobility behavior of nineteen chemical warfare agents (7 nerve gases, 5 blister agents, 2 lachrymators, 2 blood agents, 3 choking agents) and related compounds including simulants (8 agents) and organic solvents (39) was comparably investigated by the ion mobility spectrometry instrument utilizing weak electric field linear drift tube with corona discharge ionization, ammonia doping, purified inner air drift flow circulation operated at ambient temperature and pressure. Three alkyl methylphosphonofluoridates, tabun, and four organophosphorus simulants gave the intense characteristic positive monomer-derived ion peaks and small dimer-derived ion peaks, and the later ion peaks were increased with the vapor concentrations. VX, RVX and tabun gave both characteristic positive monomer-derived ions and degradation product ions. Nitrogen mustards gave the intense characteristic positive ion peaks, and in addition distinctive negative ion peak appeared from HN3. Mustard gas, lewisite 1, o-chlorobenzylidenemalononitrile and 2-mercaptoethanol gave the characteristic negative ion peaks. Methylphosphonyl difluoride, 2-chloroacetophenone and 1,4-thioxane gave the characteristic ion peaks both in the positive and negative ion mode. 2-Chloroethylethylsulfide and allylisothiocyanate gave weak ion peaks. The marker ion peaks derived from two blood agents and three choking agents were very close to the reactant ion peak in negative ion mode and the respective reduced ion mobility was fluctuated. The reduced ion mobility of the CWA monomer-derived peaks were positively correlated with molecular masses among structurally similar agents such as G-type nerve gases and organophosphorus simulants; V-type nerve gases and nitrogen mustards. The slope values of the calibration plots of the peak heights of the characteristic marker ions versus the vapor concentrations are related to the detection sensitivity, and within chemical warfare agents examined the slope values for sarin, soman

Studies on residue-free decontaminants for chemical warfare agents.

Science.gov (United States)

Wagner, George W

2015-03-17

Residue-free decontaminants based on hydrogen peroxide, which decomposes to water and oxygen in the environment, are examined as decontaminants for chemical warfare agents (CWA). For the apparent special case of CWA on concrete, H2O2 alone, without any additives, effectively decontaminates S-2-(diisopropylamino)ethyl O-ethyl methylphosphonothioate (VX), pinacolyl methylphosphorofluoridate (GD), and bis(2-choroethyl) sulfide (HD) in a process thought to involve H2O2 activation by surface-bound carbonates/bicarbonates (known H2O2 activators for CWA decontamination). A plethora of products are formed during the H2O2 decontamination of HD on concrete, and these are characterized by comparison to synthesized authentic compounds. As a potential residue-free decontaminant for surfaces other than concrete (or those lacking adsorbed carbonate/bicarbonate) H2O2 activation for CWA decontamination is feasible using residue-free NH3 and CO2 as demonstrated by reaction studies for VX, GD, and HD in homogeneous solution. Although H2O2/NH3/CO2 ("HPAC") decontaminants are active for CWA decontamination in solution, they require testing on actual surfaces of interest to assess their true efficacy for surface decontamination.

Binding of chemical warfare agent simulants as guests in a coordination cage: contributions to binding and a fluorescence-based response.

Science.gov (United States)

Taylor, Christopher G P; Piper, Jerico R; Ward, Michael D

2016-05-07

Cubic coordination cages act as competent hosts for several alkyl phosphonates used as chemical warfare agent simulants; a range of cage/guest structures have been determined, contributions to guest binding analysed, and a fluorescent response to guest binding demonstrated.

Chemiresistor Devices for Chemical Warfare Agent Detection Based on Polymer Wrapped Single-Walled Carbon Nanotubes.

Science.gov (United States)

Fennell, John F; Hamaguchi, Hitoshi; Yoon, Bora; Swager, Timothy M

2017-04-28

Chemical warfare agents (CWA) continue to present a threat to civilian populations and military personnel in operational areas all over the world. Reliable measurements of CWAs are critical to contamination detection, avoidance, and remediation. The current deployed systems in United States and foreign militaries, as well as those in the private sector offer accurate detection of CWAs, but are still limited by size, portability and fabrication cost. Herein, we report a chemiresistive CWA sensor using single-walled carbon nanotubes (SWCNTs) wrapped with poly(3,4-ethylenedioxythiophene) (PEDOT) derivatives. We demonstrate that a pendant hexafluoroisopropanol group on the polymer that enhances sensitivity to a nerve agent mimic, dimethyl methylphosphonate, in both nitrogen and air environments to concentrations as low as 5 ppm and 11 ppm, respectively. Additionally, these PEDOT/SWCNT derivative sensor systems experience negligible device performance over the course of two weeks under ambient conditions.

Chemical peeling in ethnic/dark skin.

Science.gov (United States)

Roberts, Wendy E

2004-01-01

Chemical peeling for skin of color arose in ancient Egypt, Mesopotamia, and other ancient cultures in and around Africa. Our current fund of medical knowledge regarding chemical peeling is a result of centuries of experience and research. The list of agents for chemical peeling is extensive. In ethnic skin, our efforts are focused on superficial and medium-depth peeling agents and techniques. Indications for chemical peeling in darker skin include acne vulgaris, postinflammatory hyperpigmentation, melasma, scarring, photodamage, and pseudofolliculitis barbae. Careful selection of patients for chemical peeling should involve not only identification of Fitzpatrick skin type, but also determining ethnicity. Different ethnicities may respond unpredictably to chemical peeling regardless of skin phenotype. Familiarity with the properties each peeling agent used is critical. New techniques discussed for chemical peeling include spot peeling for postinflammatory hyperpigmentation and combination peels for acne and photodamage. Single- or combination-agent chemical peels are shown to be efficacious and safe. In conclusion, chemical peeling is a treatment of choice for numerous pigmentary and scarring disorders arising in dark skin tones. Familiarity with new peeling agents and techniques will lead to successful outcomes.

Destruction of chemical agent simulants in a supercritical water oxidation bench-scale reactor

Energy Technology Data Exchange (ETDEWEB)

Veriansyah, Bambang [Supercritical Fluid Research Laboratory, Clean Technology Research Center, Korea Institute of Science and Technology (KIST), 39-1 Hawolgok-dong, Seongbuk-gu, Seoul 136-791 (Korea, Republic of) and Department of Green Process and System Engineering, University of Science and Technology, 39-1 Hawolgok-dong, Seongbuk-gu, Seoul 136-791 (Korea, Republic of)]. E-mail: vaveri@kist.re.kr; Kim, Jae-Duck [Supercritical Fluid Research Laboratory, Clean Technology Research Center, Korea Institute of Science and Technology (KIST), 39-1 Hawolgok-dong, Seongbuk-gu, Seoul 136-791 (Korea, Republic of) and Department of Green Process and System Engineering, University of Science and Technology, 39-1 Hawolgok-dong, Seongbuk-gu, Seoul 136-791 (Korea, Republic of)]. E-mail: jdkim@kist.re.kr; Lee, Jong-Chol [Agency for Defense Development (ADD), P.O. Box 35-1, Yuseong-gu, Daejeon (Korea, Republic of)]. E-mail: jcleeadd@hanafos.com

2007-08-17

A new design of supercritical water oxidation (SCWO) bench-scale reactor has been developed to handle high-risk wastes resulting from munitions demilitarization. The reactor consists of a concentric vertical double wall in which SCWO reaction takes place inside an inner tube (titanium grade 2, non-porous) whereas pressure resistance is ensured by a Hastelloy C-276 external vessel. The performances of this reactor were investigated with two different kinds of chemical warfare agent simulants: OPA (a mixture of isopropyl amine and isopropyl alcohol) as the binary precursor for nerve agent of sarin and thiodiglycol [TDG (HOC{sub 2}H{sub 4}){sub 2}S] as the model organic sulfur heteroatom. High destruction rates based on total organic carbon (TOC) were achieved (>99.99%) without production of chars or undesired gases such as carbon monoxide and methane. The carbon-containing product was carbon dioxide whereas the nitrogen-containing products were nitrogen and nitrous oxide. Sulfur was totally recovered in the aqueous effluent as sulfuric acid. No corrosion was noticed in the reactor after a cumulative operation time of more than 250 h. The titanium tube shielded successfully the pressure vessel from corrosion.

Metal Ion-Catalyzed Alcoholysis as a Strategy for the High Loading Destruction of Chemical Warfare Organophosphorus Agents

Science.gov (United States)

2013-11-01

agents (CWAs). Whether these inhibitors are used as pesticides or CWAs, all act in the same way by inhibiting an enzyme (a cholinesterase ), thereby...phosphinate, and phosphonate esters are potent acetylcholinesterase inhibitors that are used as animal and crop protectants and chemical warfare...for these inhibitors are used annually, accounting for 70% of all insecticides used for agriculture, in homes and gardens, and for government

Iron oxide functionalized graphene nano-composite for dispersive solid phase extraction of chemical warfare agents from aqueous samples.

Science.gov (United States)

Chinthakindi, Sridhar; Purohit, Ajay; Singh, Varoon; Tak, Vijay; Goud, D Raghavender; Dubey, D K; Pardasani, Deepak

2015-05-15

Present study deals with the preparation and evaluation of graphene based magnetic nano-composite for dispersive solid phase extraction of Chemical Weapons Convention (CWC) relevant chemicals from aqueous samples. Nano-composite, Fe3O4@SiO2-G was synthesized by covalently bonding silica coated Fe3O4 onto the graphene sheets. Nerve agents (NA), Sulfur mustard (SM) and their non-toxic environmental markers were the target analytes. Extraction parameters like amount of sorbent, extraction time and desorption conditions were optimized. Dispersion of 20 milligram of sorbent in 200mL of water sample for 20min. followed by methanol/chloroform extraction produced average to good recoveries (27-94%) of targeted analytes. Recoveries of real agents exhibited great dependency upon sample pH and ionic strength. Sarin produced maximum recovery under mild acidic conditions (56% at pH 5) while VX demanded alkaline media (83% at pH 9). Salts presence in the aqueous samples was found to be advantageous, raising the recoveries to as high as 94% for SM. Excellent limits of detection (LOD) for sulphur mustard and VX (0.11ngmL(-1) and 0.19ngmL(-1) respectively) proved the utility of the developed method for the off-site analysis of CWC relevant chemicals. Copyright © 2015 Elsevier B.V. All rights reserved.

Supramolecular chemistry and chemical warfare agents: from fundamentals of recognition to catalysis and sensing.

Science.gov (United States)

Sambrook, M R; Notman, S

2013-12-21

Supramolecular chemistry presents many possible avenues for the mitigation of the effects of chemical warfare agents (CWAs), including sensing, catalysis and sequestration. To-date, efforts in this field both to study fundamental interactions between CWAs and to design and exploit host systems remain sporadic. In this tutorial review the non-covalent recognition of CWAs is considered from first principles, including taking inspiration from enzymatic systems, and gaps in fundamental knowledge are indicated. Examples of synthetic systems developed for the recognition of CWAs are discussed with a focus on the supramolecular complexation behaviour and non-covalent approaches rather than on the proposed applications.

Characterization of in vitro phenotypes of Burkholderia pseudomallei and Burkholderia mallei strains potentially associated with persistent infection in mice.

Science.gov (United States)

Bernhards, R C; Cote, C K; Amemiya, K; Waag, D M; Klimko, C P; Worsham, P L; Welkos, S L

2017-03-01

Burkholderia pseudomallei (Bp) and Burkholderia mallei (Bm), the agents of melioidosis and glanders, respectively, are Tier 1 biothreats. They infect humans and animals, causing disease ranging from acute and fatal to protracted and chronic. Chronic infections are especially challenging to treat, and the identification of in vitro phenotypic markers which signal progression from acute to persistent infection would be extremely valuable. First, a phenotyping strategy was developed employing colony morphotyping, chemical sensitivity testing, macrophage infection, and lipopolysaccharide fingerprint analyses to distinguish Burkholderia strains. Then mouse spleen isolates collected 3-180 days after infection were characterized phenotypically. Isolates from long-term infections often exhibited increased colony morphology differences and altered patterns of antimicrobial sensitivity and macrophage infection. Some of the Bp and Bm persistent infection isolates clearly displayed enhanced virulence in mice. Future studies will evaluate the potential role and significance of these phenotypic markers in signaling the establishment of a chronic infection.

Guidelines for Use of Personal Protective Equipment by Law Enforcement Personnel During a Terrorist Chemical Agent Incident. Revision 2

Science.gov (United States)

2003-12-01

dispersion models detailed by Stuempfle6. The nature of the missions identified for SWAT teams may require them to operate indoors where chemical...depressants (BZ, marijuana ) have a delayed action rate of 2 to 4 hours if inhaled, and up to 36 hours from skin absorption. • Persistency—BZ is very...persistent in soil, water, and on surfaces. • Odor—BZ has no odor. Marijuana has a distinct smell. • Primary hazard—Respiratory, skin absorption

Microbial Pest Control Agents: Are they a Specific And Safe Tool for Insect Pest Management?

Science.gov (United States)

Deshayes, Caroline; Siegwart, Myriam; Pauron, David; Froger, Josy-Anne; Lapied, Bruno; Apaire-Marchais, Véronique

2017-01-01

Microorganisms (viruses, bacteria and fungi) or their bioactive agents can be used as active substances and therefore are referred as Microbial Pest Control Agents (MPCA). They are used as alternative strategies to chemical insecticides to counteract the development of resistances and to reduce adverse effects on both environment and human health. These natural entomopathogenic agents, which have specific modes of action, are generally considered safer as compared to conventional chemical insecticides. Baculoviruses are the only viruses being used as the safest biological control agents. They infect insects and have narrow host ranges. Bacillus thuringiensis (Bt) is the most widely and successfully used bioinsecticide in the integrated pest management programs in the world. Bt mainly produces crystal delta-endotoxins and secreted toxins. However, the Bt toxins are not stable for a very long time and are highly sensitive to solar UV. So genetically modified plants that express toxins have been developed and represent a large part of the phytosanitary biological products. Finally, entomopathogenic fungi and particularly, Beauveria bassiana and Metarhizium anisopliae, are also used for their insecticidal properties. Most studies on various aspects of the safety of MPCA to human, non-target organisms and environment have only reported acute but not chronic toxicity. This paper reviews the modes of action of MPCA, their toxicological risks to human health and ecotoxicological profiles together with their environmental persistence. This review is part of the special issue "Insecticide Mode of Action: From Insect to Mammalian Toxicity". Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Degradation of Paraoxon and the Chemical Warfare Agents VX, Tabun, and Soman by the Metal-Organic Frameworks UiO-66-NH2, MOF-808, NU-1000, and PCN-777

NARCIS (Netherlands)

Koning, M.C. de; Grol, M. van; Breijaert, T.

2017-01-01

In recent years, Zr-based metal-organic frameworks (MOFs) have been developed that facilitate catalytic degradation of toxic organophosphate agents, such as chemical warfare agents (CWAs). Because of strict regulations, experiments using live agents are not possible for most laboratories and, as a

Degradation of Paraoxon and the Chemical Warfare Agents VX, Tabun, and Soman by the Metal−Organic Frameworks UiO-66-NH2, MOF-808, NU-1000, and PCN-777

NARCIS (Netherlands)

Koning, M.C. de; Grol, M. van; Breijaert, T.C.

2017-01-01

In recent years, Zr-based metal−organic frameworks (MOFs) have been developed that facilitate catalytic degradation of toxic organophosphate agents, such as chemical warfare agents (CWAs). Because of strict regulations, experiments using live agents are not possible for most laboratories and, as a

Environmental Chemicals in Breast Milk

Science.gov (United States)

Most of the information available on environmental chemicals in breast milk is focused on persistent, lipophilic chemicals; the database on levels of these chemicals has expanded substantially since the 1950s. Currently, various types of chemicals are measured in breast milk and ...

Complexing Agents and pH Influence on Chemical Durability of Type I Molded Glass Containers.

Science.gov (United States)

Biavati, Alberto; Poncini, Michele; Ferrarini, Arianna; Favaro, Nicola; Scarpa, Martina; Vallotto, Marta

2017-01-01

Among the factors that affect the glass surface chemical durability, pH and complexing agents present in aqueous solution have the main role. Glass surface attack can be also related to the delamination issue causing glass particles' appearance in the pharmaceutical preparation. A few methods to check for glass containers delamination propensity and some control guidelines have been proposed. The present study emphasizes the possible synergy between a few complexing agents with pH on borosilicate glass chemical durability.Hydrolytic attack was performed in small-volume 23 mL type I glass containers autoclaved according to the European Pharmacopoeia or United States Pharmacopeia for 1 h at 121 °C, in order to enhance the chemical attack due to time, temperature, and the unfavorable surface/volume ratio. Solutions of 0.048 M or 0.024 M (M/L) of the acids citric, glutaric, acetic, EDTA (ethylenediaminetetraacetic acid), together with sodium phosphate with water for comparison, were used for the trials. The pH was adjusted ±0.05 units at fixed values 5.5, 6.6, 7, 7.4, 8, and 9 by LiOH diluted solution.Because silicon is the main glass network former, silicon release into the attack solutions was chosen as the main index of the glass surface attack and analysed by inductively coupled plasma atomic emission spectrophotometry. The work was completed by the analysis of the silicon release in the worst attack conditions of molded glass, soda lime type II glass, and tubing borosilicate glass vials to compare different glass compositions and forming technologies. Surface analysis by scanning electron microscopy was finally performed to check for the surface status after the worst chemical attack condition by citric acid. LAY ABSTRACT: Glass, like every packaging material, can have some usage limits, mainly in basic pH solutions. The issue of glass surface degradation particles that appear in vials (delamination) has forced a number of drug product recalls in recent years

Air Activated Self-Decontaminating Polydicyclopentadiene PolyHIPE Foams for Rapid Decontamination of Chemical Warfare Agents.

Science.gov (United States)

McGann, Christopher L; Daniels, Grant C; Giles, Spencer L; Balow, Robert B; Miranda-Zayas, Jorge L; Lundin, Jeffrey G; Wynne, James H

2018-06-01

The threat of chemical warfare agents (CWA) compels research into novel self-decontaminating materials (SDM) for the continued safety of first-responders, civilians, and active service personnel. The capacity to actively detoxify, as opposed to merely sequester, offending agents under typical environmental conditions defines the added value of SDMs in comparison to traditional adsorptive materials. Porous polymers, synthesized via the high internal phase emulsion (HIPE) templating, provide a facile fabrication method for materials with permeable open cellular structures that may serve in air filtration applications. PolyHIPEs comprising polydicyclopentadiene (polyDCPD) networks form stable hydroperoxide species following activation in air under ambient conditions. The hydroperoxide-containing polyDCPD materials react quickly with CWA simulants, Demeton-S and 2-chloroethyl ethyl sulfide, forming oxidation products as confirmed via gas chromatography mass spectrometry. The simplicity of the detoxification chemistry paired with the porous foam form factor presents an exciting opportunity for the development of self-decontaminating filter media. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Global contamination trends of persistent organic chemicals

National Research Council Canada - National Science Library

Loganathan, Bommanna G; Lam, Paul K. S

2012-01-01

"Composed by a diverse group of experts, this reference covers the history, present status, and projected future trends of environmental contamination from highly toxic synthetic chemical pollutants...

Development of haemostatic decontaminants for the treatment of wounds contaminated with chemical warfare agents. 2: evaluation of in vitro topical decontamination efficacy using undamaged skin.

Science.gov (United States)

Dalton, Christopher H; Hall, Charlotte A; Lydon, Helen L; Chipman, J K; Graham, John S; Jenner, John; Chilcott, Robert P

2015-05-01

The risk of penetrating, traumatic injury occurring in a chemically contaminated environment cannot be discounted. Should a traumatic injury be contaminated with a chemical warfare (CW) agent, it is likely that standard haemostatic treatment options would be complicated by the need to decontaminate the wound milieu. Thus, there is a need to develop haemostatic products that can simultaneously arrest haemorrhage and decontaminate CW agents. The purpose of this study was to evaluate a number of candidate haemostats for efficacy as skin decontaminants against three CW agents (soman, VX and sulphur mustard) using an in vitro diffusion cell containing undamaged pig skin. One haemostatic product (WoundStat™) was shown to be as effective as the standard military decontaminants Fuller's earth and M291 for the decontamination of all three CW agents. The most effective haemostatic agents were powder-based and use fluid absorption as a mechanism of action to sequester CW agent (akin to the decontaminant Fuller's earth). The envisaged use of haemostatic decontaminants would be to decontaminate from within wounds and from damaged skin. Therefore, WoundStat™ should be subject to further evaluation using an in vitro model of damaged skin. Copyright © 2014 Crown copyright. Journal of Applied Toxicology © 2014 John Wiley & Sons, Ltd.

Mobility-induced persistent chimera states

Science.gov (United States)

Petrungaro, Gabriela; Uriu, Koichiro; Morelli, Luis G.

2017-12-01

We study the dynamics of mobile, locally coupled identical oscillators in the presence of coupling delays. We find different kinds of chimera states in which coherent in-phase and antiphase domains coexist with incoherent domains. These chimera states are dynamic and can persist for long times for intermediate mobility values. We discuss the mechanisms leading to the formation of these chimera states in different mobility regimes. This finding could be relevant for natural and technological systems composed of mobile communicating agents.

Specificity enhancement by electrospray ionization multistage mass spectrometry--a valuable tool for differentiation and identification of 'V'-type chemical warfare agents.

Science.gov (United States)

Weissberg, Avi; Tzanani, Nitzan; Dagan, Shai

2013-12-01

The use of chemical warfare agents has become an issue of emerging concern. One of the challenges in analytical monitoring of the extremely toxic 'V'-type chemical weapons [O-alkyl S-(2-dialkylamino)ethyl alkylphosphonothiolates] is to distinguish and identify compounds of similar structure. MS analysis of these compounds reveals mostly fragment/product ions representing the amine-containing residue. Hence, isomers or derivatives with the same amine residue exhibit similar mass spectral patterns in both classical EI/MS and electrospray ionization-MS, leading to unavoidable ambiguity in the identification of the phosphonate moiety. A set of five 'V'-type agents, including O-ethyl S-(2-diisopropylamino)ethyl methylphosphonothiolate (VX), O-isobutyl S-(2-diethylamino)ethyl methylphosphonothiolate (RVX) and O-ethyl S-(2-diethylamino)ethyl methylphosphonothiolate (VM) were studied by liquid chromatography/electrospray ionization/MS, utilizing a QTRAP mass detector. MS/MS enhanced product ion scans and multistage MS(3) experiments were carried out. Based on the results, possible fragmentation pathways were proposed, and a method for the differentiation and identification of structural isomers and derivatives of 'V'-type chemical warfare agents was obtained. MS/MS enhanced product ion scans at various collision energies provided information-rich spectra, although many of the product ions obtained were at low abundance. Employing MS(3) experiments enhanced the selectivity for those low abundance product ions and provided spectra indicative of the different phosphonate groups. Study of the fragmentation pathways, revealing some less expected structures, was carried out and allowed the formulation of mechanistic rules and the determination of sets of ions typical of specific groups, for example, methylphosphonothiolates versus ethylphosphonothiolates. The new group-specific ions elucidated in this work are also useful for screening unknown 'V'-type agents and related

Cefepime vs other antibacterial agents for the treatment of Enterobacter species bacteremia.

Science.gov (United States)

Siedner, Mark J; Galar, Alicia; Guzmán-Suarez, Belisa B; Kubiak, David W; Baghdady, Nour; Ferraro, Mary Jane; Hooper, David C; O'Brien, Thomas F; Marty, Francisco M

2014-06-01

Carbapenems are recommended for treatment of Enterobacter infections with AmpC phenotypes. Although isolates are typically susceptible to cefepime in vitro, there are few data supporting its clinical efficacy. We reviewed all cases of Enterobacter species bacteremia at 2 academic hospitals from 2005 to 2011. Outcomes of interest were (1) persistent bacteremia ≥1 calendar day and (2) in-hospital mortality. We fit logistic regression models, adjusting for clinical risk factors and Pitt bacteremia score and performed propensity score analyses to compare the efficacy of cefepime and carbapenems. Three hundred sixty-eight patients experienced Enterobacter species bacteremia and received at least 1 antimicrobial agent, of whom 52 (14%) died during hospitalization. Median age was 59 years; 19% were neutropenic, and 22% were in an intensive care unit on the day of bacteremia. Twenty-nine (11%) patients had persistent bacteremia for ≥1 day after antibacterial initiation. None of the 36 patients who received single-agent cefepime (0%) had persistent bacteremia, as opposed to 4 of 16 (25%) of those who received single-agent carbapenem (P Enterobacter species bacteremia. Its use should be further explored as a carbapenem-sparing agent in this clinical scenario.

Rapid screening of N-oxides of chemical warfare agents degradation products by ESI-tandem mass spectrometry.

Science.gov (United States)

Sridhar, L; Karthikraj, R; Lakshmi, V V S; Raju, N Prasada; Prabhakar, S

2014-08-01

Rapid detection and identification of chemical warfare agents and related precursors/degradation products in various environmental matrices is of paramount importance for verification of standards set by the chemical weapons convention (CWC). Nitrogen mustards, N,N-dialkylaminoethyl-2-chlorides, N,N-dialkylaminoethanols, N-alkyldiethanolamines, and triethanolamine, which are listed CWC scheduled chemicals, are prone to undergo N-oxidation in environmental matrices or during decontamination process. Thus, screening of the oxidized products of these compounds is also an important task in the verification process because the presence of these products reveals alleged use of nitrogen mustards or precursors of VX compounds. The N-oxides of aminoethanols and aminoethylchlorides easily produce [M + H](+) ions under electrospray ionization conditions, and their collision-induced dissociation spectra include a specific neutral loss of 48 u (OH + CH2OH) and 66 u (OH + CH2Cl), respectively. Based on this specific fragmentation, a rapid screening method was developed for screening of the N-oxides by applying neutral loss scan technique. The method was validated and the applicability of the method was demonstrated by analyzing positive and negative samples. The method was useful in the detection of N-oxides of aminoethanols and aminoethylchlorides in environmental matrices at trace levels (LOD, up to 500 ppb), even in the presence of complex masking agents, without the use of time-consuming sample preparation methods and chromatographic steps. This method is advantageous for the off-site verification program and also for participation in official proficiency tests conducted by the Organization for the Prohibition of Chemical Weapons (OPCW), the Netherlands. The structure of N-oxides can be confirmed by the MS/MS experiments on the detected peaks. A liquid chromatography-mass spectrometry (LC-MS) method was developed for the separation of isomeric N-oxides of aminoethanols and

Chemical Microsensors For Detection Of Explosives And Chemical Warfare Agents

Science.gov (United States)

Yang, Xiaoguang; Swanson, Basil I.

2001-11-13

An article of manufacture is provided including a substrate having an oxide surface layer and a layer of a cyclodextrin derivative chemically bonded to said substrate, said layer of a cyclodextrin derivative adapted for the inclusion of selected compounds, e.g., nitro-containing organic compounds, therewith. Such an article can be a chemical microsensor capable of detecting a resultant mass change from inclusion of the nitro-containing organic compound.

The energetic and chemical signatures of persistent soil organic matter

DEFF Research Database (Denmark)

Barré, Pierre; Plante, Alain F.; Cecillon, Lauric

2016-01-01

A large fraction of soil organic matter (OM) resists decomposition over decades to centuries as indicated by long radiocarbon residence times, but the mechanisms responsible for the long-term (multi-decadal) persistence are debated. The current lack of mechanistic understanding limits our ability...

The role of genetic background in susceptibility to chemical warfare nerve agents across rodent and non-human primate models.

Science.gov (United States)

Matson, Liana M; McCarren, Hilary S; Cadieux, C Linn; Cerasoli, Douglas M; McDonough, John H

2018-01-15

Genetics likely play a role in various responses to nerve agent exposure, as genetic background plays an important role in behavioral, neurological, and physiological responses to environmental stimuli. Mouse strains or selected lines can be used to identify susceptibility based on background genetic features to nerve agent exposure. Additional genetic techniques can then be used to identify mechanisms underlying resistance and sensitivity, with the ultimate goal of developing more effective and targeted therapies. Here, we discuss the available literature on strain and selected line differences in cholinesterase activity levels and response to nerve agent-induced toxicity and seizures. We also discuss the available cholinesterase and toxicity literature across different non-human primate species. The available data suggest that robust genetic differences exist in cholinesterase activity, nerve agent-induced toxicity, and chemical-induced seizures. Available cholinesterase data suggest that acetylcholinesterase activity differs across strains, but are limited by the paucity of carboxylesterase data in strains and selected lines. Toxicity and seizures, two outcomes of nerve agent exposure, have not been fully evaluated for genetic differences, and thus further studies are required to understand baseline strain and selected line differences. Published by Elsevier B.V.

Systemic treatment of advanced, persistent or recurrent cervical cancer

International Nuclear Information System (INIS)

Reckova, M.

2015-01-01

The cervical cancer is the third most common malignancy in women in the world. Despite advances in screening and treatment there are a relatively large number of patients who are diagnosed with advanced stage of disease, or who have inoperable recurrence. In this group of patients, the main aim of a treatment is palliative intent. The main cytotoxic agent is cisplatin, but the responses are also observed with other chemotherapy agents. Improved therapeutic results are observed with combined platinum-based chemotherapy regimens as compared to cisplatin monotherapy. Overall, however, the treatment results in advanced, persistent and recurrent cervical cancer are unfavorable and disease is considered to be relatively chemo resistant. The new treatment approaches are searched and a significant therapeutic benefit, as far as progression-free and overall survival, has been recently demonstrated when adding bevacizumab to systemic chemotherapy. The current article is a review of systemic treatment in advanced, persistent and recurrent metastatic carcinoma of the cervix. (author)

Applying radiation approaches to the control of public risks from chemical agents

International Nuclear Information System (INIS)

Alexander, R.E.

1989-01-01

risks from chemical and biological agents, the technical people involved should make certain that the major scientific considerations have a prominent role in the decision-making processes, not just assumptions, hypotheses and axioms adopted in lieu of facts

Protective effect of conditioning agents on Afro-ethnic hair chemically treated with thioglycolate-based straightening emulsion.

Science.gov (United States)

Dias, Tania Cristina de Sá; Baby, André Rolim; Kaneko, Telma Mary; Velasco, Maria Valéria Robles

2008-06-01

Straightening is a chemical process by which excessively curly hair is straightened in an irreversible way. Generally, products are formulated as emulsions with high pH value (9.0-12.0), which, after applied on hair, cause considerable damage, making it dry and fragile. This research work evaluated the protective effect of lauryl PEG/PPG-18/18 methicone, cyclopentasiloxane (and) PEG-12 dimethicone cross-polymer, jojoba oil, and aqua (and) cystine bis-PG propyl silanetriol, as conditioning agents, on Afro-ethnic hair locks treated with thioglycolate-based straightening emulsions by protein loss, combability, and traction to rupture. Standard Afro-ethnic hair locks were prepared following a protocol for straightening emulsion application. Considering the assays performed, the addition of conditioning agents to the straightening emulsion with ammonium thioglycolate benefited the hair fiber, thus diminishing protein loss, protecting the hair thread, and improving resistance to breakage. Jojoba oil and lauryl PEG/PPG-18/18 methicone were the conditioning agents that presented the best results. Straightening emulsions with ammonium thioglycolate containing aqua (and) cystine bis-PG propyl silanetriol and cyclopentasiloxane (and) PEG-12 dimethicone cross-polymer were the ones that provided higher breakage resistance of the thread.

Low environmental radiation background impairs biological defence of the yeast Saccharomyces cerevisiae to chemical radiomimetic agents

International Nuclear Information System (INIS)

Satta, L.; Augusti-Tocco, G.; Ceccarelli, R.; Paggi, P.; Scarsella, G.; Esposito, A.; Fiore, M.; Poggesi, I.; Ricordy, R.; Cundari, E.

1995-01-01

Background radiation is likely to constitute one of the factors involved in biological evolution since radiations are able to affect biological processes. Therefore, it is possible to hypothesize that organisms are adapted to environmental background radiation and that this adaptation could increase their ability to respond to the harmful effects of ionizing radiations. In fact, adaptive responses to alkylating agents and to low doses of ionizing radiation have been found in many organisms. In order to test for effects of adaptation, cell susceptibility to treatments with high doses of radiomimetic chemical agents has been studied by growing them in a reduced environmental radiation background. The experiment has been performed by culturing yeast cells (Saccharomyces cerevisiae D7) in parallel in a standard background environment and in the underground Gran Sasso National Laboratory, with reduced environmental background radiation. After a conditioning period, yeast cells were exposed to recombinogenic doses of methyl methanesulfonate. The yeast cells grown in the Gran Sasso Laboratory showed a higher frequency of radiomimetic induced recombination as compared to those grown in the standard environment. This suggests that environmental radiation may act as a conditioning agent

Mesoscopic effects in an agent-based bargaining model in regular lattices.

Science.gov (United States)

Poza, David J; Santos, José I; Galán, José M; López-Paredes, Adolfo

2011-03-09

The effect of spatial structure has been proved very relevant in repeated games. In this work we propose an agent based model where a fixed finite population of tagged agents play iteratively the Nash demand game in a regular lattice. The model extends the multiagent bargaining model by Axtell, Epstein and Young modifying the assumption of global interaction. Each agent is endowed with a memory and plays the best reply against the opponent's most frequent demand. We focus our analysis on the transient dynamics of the system, studying by computer simulation the set of states in which the system spends a considerable fraction of the time. The results show that all the possible persistent regimes in the global interaction model can also be observed in this spatial version. We also find that the mesoscopic properties of the interaction networks that the spatial distribution induces in the model have a significant impact on the diffusion of strategies, and can lead to new persistent regimes different from those found in previous research. In particular, community structure in the intratype interaction networks may cause that communities reach different persistent regimes as a consequence of the hindering diffusion effect of fluctuating agents at their borders.

Mesoscopic effects in an agent-based bargaining model in regular lattices.

Directory of Open Access Journals (Sweden)

David J Poza

Full Text Available The effect of spatial structure has been proved very relevant in repeated games. In this work we propose an agent based model where a fixed finite population of tagged agents play iteratively the Nash demand game in a regular lattice. The model extends the multiagent bargaining model by Axtell, Epstein and Young modifying the assumption of global interaction. Each agent is endowed with a memory and plays the best reply against the opponent's most frequent demand. We focus our analysis on the transient dynamics of the system, studying by computer simulation the set of states in which the system spends a considerable fraction of the time. The results show that all the possible persistent regimes in the global interaction model can also be observed in this spatial version. We also find that the mesoscopic properties of the interaction networks that the spatial distribution induces in the model have a significant impact on the diffusion of strategies, and can lead to new persistent regimes different from those found in previous research. In particular, community structure in the intratype interaction networks may cause that communities reach different persistent regimes as a consequence of the hindering diffusion effect of fluctuating agents at their borders.

Meta-analysis of studies on chemical, physical and biological agents in the control of Aedes aegypti.

Science.gov (United States)

Lima, Estelita Pereira; Goulart, Marília Oliveira Fonseca; Rolim Neto, Modesto Leite

2015-09-04

Aedes aegypti is a vector of international concern because it can transmit to humans three important arboviral diseases: yellow fever, dengue and chikungunya. Epidemics that are repeated year after year in a variety of urban centers indicate that there are control failures, allowing the vector to continue expanding. To identify the most effective vector control strategies and the factors that contributed to the success or failure of each strategy, we carried out a systematic review with meta-analysis of articles published in 12 databases, from 1974 to the month of December 2013. We evaluated the association between the use of whatever chemical substance, mechanical agent, biological or integrated actions against A. aegypti and the control of the vector, as measured by 10 indicators. We found 2,791 articles, but after careful selection, only 26 studies remained for analysis related to control interventions implemented in 15 countries, with 5 biological, 5 chemical, 3 mechanical and 13 integrated strategies. The comparison among all of them, indicated that the control of A. aegypti is significantly associated with the type of strategy used, and that integrated interventions consist of the most effective method for controlling A. aegypti. The most effective control method was the integrated approach, considering the influence of eco-bio-social determinants in the virus-vector-man epidemiological chain, and community involvement, starting with community empowerment as active agents of vector control.

PERSISTENT ORGANIC POLLUTANS (POPS DAN KONVENSI STOCKHOLM

Directory of Open Access Journals (Sweden)

Lina Warlina

2010-07-01

Full Text Available Persistent organic pollutants (POPs are toxic chemicals that adversely affect human health and the environment around the world. Because they can be transported by wind and water, most POPs generated in one country can affect people and wildlife far from where they are used and released. They persist for long periods of time in the environment and can accumulate and pass from one species to the next through the food chain. To address this global concern, many countries in the world joined forces with 90 other countries and the European Community to sign a groundbreaking United Nations treaty in Stockholm, Sweden, in May 2001, known as the Stockholm Convention. One of important agreement is all countries agreed to reduce or eliminate the production, use, and/or release of 12 key POPs. The Convention specifies a scientific review process that could lead to the addition of other POPs chemicals of global concern. POPs include a range of substances that include intentionally produced chemicals currently or once used in agriculture, disease control, manufacturing, or industrial processes. Also it can be produced by unintentionally produced chemicals, such as dioxins, that result from some industrial processes and from combustion (for example, municipal and medical waste incineration and backyard burning of trash.

Equilibrium Sampling to Determine the Thermodynamic Potential for Bioaccumulation of Persistent Organic Pollutants from Sediment

DEFF Research Database (Denmark)

Jahnke, Annika; MacLeod, Matthew; Wickström, Håkan

2014-01-01

Equilibrium partitioning (EqP) theory is currently the most widely used approach for linking sediment pollution by persistent hydrophobic organic chemicals to bioaccumulation. Most applications of the EqP approach assume (I) a generic relationship between organic carbon-normalized chemical...... chemical concentrations in the silicone, and applying lipid/silicone partition ratios to yield concentrations in lipid at thermodynamic equilibrium with the sediment (CLip⇌Sed). Furthermore, we evaluated the validity of assumption II by comparing CLip⇌Sed of selected persistent, bioaccumulative and toxic...... organic chemicals from sediment useful to prioritize management actions to remediate contaminated sites....

Chemical Protection Testing of Sorbent-Based Air Purification Components (APCs)

Science.gov (United States)

2016-06-24

handling and storing the chemical materials of interest. Testing facilities intending to use chemical warfare agents (CWAs) and nontraditional agents...handling, and decontamination capabilities for research, development, test, and evaluation (RDT&E) quantities of chemical agents. Chemical agent...and decontaminated IAW the test plan and all test documentation will be archived. All recoverable chemical test materials will be accounted for and

Comparison of Selected Methods for Individual Decontamination of Chemical Warfare Agents

Directory of Open Access Journals (Sweden)

Tomas Capoun

2014-06-01

Full Text Available This study addresses the individual decontamination of chemical warfare agents (CWA and other hazardous substances. The individual decontamination applies to contaminated body surfaces, protective clothing and objects immediately after contamination, performed individually or by mutual assistance using prescribed or improvised devices. The article evaluates the importance of individual decontamination, security level for Fire and Rescue Service Units of the Czech Republic (FRS CR and demonstrates some of the devices. The decontamination efficiency of selected methods (sorbent, glove and sponge, two-chamber foam device and wiping with alcohol was evaluated for protective clothing and painted steel plate contaminated with O-ethyl-S-(diisopropylaminoethyl-methylthiophosphonate (VX, sulfur mustard, o-cresol and acrylonitrile. The methods were assessed from an economic point of view and with regard to specific user parameters, such as the decontamination of surfaces or materials with poor accessibility and vertical surfaces, the need for a water rinse as well as toxic waste and its disposal.

An agent-based simulation of persistent inequalities in health behavior: Understanding the interdependent roles of segregation, clustering, and social influence

Directory of Open Access Journals (Sweden)

Brent A. Langellier

2016-12-01

Full Text Available Health inequalities are conspicuously persistent through time and often durable even in spite of interventions. In this study, I use agent-based simulation models (ABMs to understand how the complex interrelationships between residential segregation, social network formation, group-level preferences, and social influence may contribute to this persistence. I use a more-stylized ABM, Bubblegum Village (BV, to understand how initial inequalities in bubblegum-chewing behaviors either endure, increase, or decrease over time given group-level differences in preferences, neighborhood-level barriers or facilitators of bubblegum chewing (e.g., access to bubblegum shops, and agents’ preferences for segregation, homophily, and clustering (i.e., the ‘tightness’ of social networks. I further use BV to understand whether segregation and social network characteristics impact whether the effects of a bubblegum-reduction intervention that is very effective in the short term are durable over time, as well as to identify intervention strategies to reduce attenuation of the intervention effects. In addition to BV, I also present results from an ABM based on the distribution and social characteristics of the population in Philadelphia, PA. This model explores similar questions to BV, but examines racial/ethnic inequalities in soda consumption based on agents’ social characteristics and baseline soda consumption probabilities informed by the 2007–2010 National Health and Nutrition Examination Survey. Collectively, the models suggest that residential segregation is a fundamental process for the production and persistence of health inequalities. The other major conclusion of the study is that, for behaviors that are subject to social influence and that cluster within social groups, interventions that are randomly-targeted to individuals with ‘bad’ behaviors will likely experience a large degree of recidivism to pre-intervention behaviors. In contrast

Chemical characterization and ecotoxicity of three soil foaming agents used in mechanized tunneling

Energy Technology Data Exchange (ETDEWEB)

Baderna, Diego, E-mail: diego.baderna@marionegri.it [Laboratory of Environmental Chemistry and Toxicology, IRCCS – Istituto di Ricerche Farmacologiche Mario Negri, Via Giuseppe La Masa 19, 20156 Milan (Italy); Lomazzi, Eleonora [Laboratory of Environmental Chemistry and Toxicology, IRCCS – Istituto di Ricerche Farmacologiche Mario Negri, Via Giuseppe La Masa 19, 20156 Milan (Italy); Passoni, Alice [Unit of Analytical Instrumentation, IRCCS – Istituto di Ricerche Farmacologiche Mario Negri, Via Giuseppe La Masa 19, 20156 Milan (Italy); Pogliaghi, Alberto; Petoumenou, Maria Ifigeneia [Laboratory of Environmental Chemistry and Toxicology, IRCCS – Istituto di Ricerche Farmacologiche Mario Negri, Via Giuseppe La Masa 19, 20156 Milan (Italy); Bagnati, Renzo [Unit of Analytical Instrumentation, IRCCS – Istituto di Ricerche Farmacologiche Mario Negri, Via Giuseppe La Masa 19, 20156 Milan (Italy); Lodi, Marco [Laboratory of Environmental Chemistry and Toxicology, IRCCS – Istituto di Ricerche Farmacologiche Mario Negri, Via Giuseppe La Masa 19, 20156 Milan (Italy); Viarengo, Aldo; Sforzini, Susanna [Department of Sciences and Technological Innovation (DiSIT), University of Piemonte Orientale “A. Avogadro”, 15121 Alessandria (Italy); Benfenati, Emilio [Laboratory of Environmental Chemistry and Toxicology, IRCCS – Istituto di Ricerche Farmacologiche Mario Negri, Via Giuseppe La Masa 19, 20156 Milan (Italy); Fanelli, Roberto [Department of Environmental Health Sciences, IRCCS – Istituto di Ricerche Farmacologiche Mario Negri, Via Giuseppe La Masa 19, 20156 Milan (Italy)

2015-10-15

Highlights: • An integrated approach was applied to study three foaming agents. • Several compounds not reported on the safety data sheets were identified by HRMS. • Environmental impacts were investigated with a battery of biological assays. • An ecotoxicological ranking of the products was obtained. - Abstract: The construction of tunnels and rocks with mechanized drills produces several tons of rocky debris that are today recycled as construction material or as soil replacement for covering rocky areas. The lack of accurate information about the environmental impact of these excavated rocks and foaming agents added during the excavation process has aroused increasing concern for ecosystems and human health. The present study proposes an integrated approach to the assessment of the potential environmental impact of three foaming agents containing different anionic surfactants and other polymers currently on the market and used in tunnel boring machines. The strategy includes chemical characterization with high resolution mass spectrometry techniques to identify the components of each product, the use of in silico tools to perform a similarity comparison among these compounds and some pollutants already listed in regulatory frameworks to identify possible threshold concentrations of contamination, and the application of a battery of ecotoxicological assays to investigate the impact of each foaming mixture on model organisms of soil (higher plants and Eisenia andrei) and water communities (Daphnia magna). The study identified eleven compounds not listed on the material safety data sheets for which we have identified possible concentrations of contamination based on existing regulatory references. The bioassays allowed us to determine the no effect concentrations (NOAECs) of the three mixtures, which were subsequently used as threshold concentration for the product in its entirety. The technical mixtures used in this study have a different degree of toxicity

Chemical characterization and ecotoxicity of three soil foaming agents used in mechanized tunneling

International Nuclear Information System (INIS)

Baderna, Diego; Lomazzi, Eleonora; Passoni, Alice; Pogliaghi, Alberto; Petoumenou, Maria Ifigeneia; Bagnati, Renzo; Lodi, Marco; Viarengo, Aldo; Sforzini, Susanna; Benfenati, Emilio; Fanelli, Roberto

2015-01-01

Highlights: • An integrated approach was applied to study three foaming agents. • Several compounds not reported on the safety data sheets were identified by HRMS. • Environmental impacts were investigated with a battery of biological assays. • An ecotoxicological ranking of the products was obtained. - Abstract: The construction of tunnels and rocks with mechanized drills produces several tons of rocky debris that are today recycled as construction material or as soil replacement for covering rocky areas. The lack of accurate information about the environmental impact of these excavated rocks and foaming agents added during the excavation process has aroused increasing concern for ecosystems and human health. The present study proposes an integrated approach to the assessment of the potential environmental impact of three foaming agents containing different anionic surfactants and other polymers currently on the market and used in tunnel boring machines. The strategy includes chemical characterization with high resolution mass spectrometry techniques to identify the components of each product, the use of in silico tools to perform a similarity comparison among these compounds and some pollutants already listed in regulatory frameworks to identify possible threshold concentrations of contamination, and the application of a battery of ecotoxicological assays to investigate the impact of each foaming mixture on model organisms of soil (higher plants and Eisenia andrei) and water communities (Daphnia magna). The study identified eleven compounds not listed on the material safety data sheets for which we have identified possible concentrations of contamination based on existing regulatory references. The bioassays allowed us to determine the no effect concentrations (NOAECs) of the three mixtures, which were subsequently used as threshold concentration for the product in its entirety. The technical mixtures used in this study have a different degree of toxicity

Mixture toxicity of PBT-like chemicals

DEFF Research Database (Denmark)

Syberg, Kristian; Dai, Lina; Ramskov, Tina

addition is a suitable model for default estimations of mixture effects. One of the major challenges is therefore how to select specific chemicals for actual mixture toxicity assessments. Persistant chemicals are likely to be present in the environment for an extended period of time, thus increasing...... the likelihood of them being present in environmentally found mixtures. Persistant, bioaccumulative and toxic (PBT) chemicals are therefore a highly relevant group of chemicals to consider for mixture toxicity regulation. The present study evaluates to what extent a number of PBT-like chemicals posess concern...... beyond that of the individual components. Firstly, the effects of three chemicals with PBT-like properties (acetyl cedrene, pyrene and triclosan) was examined on the freshwater snail, Potamopyrgus antipodarum. Secondly, mixture bioaccumulation of the same three chemicals were assessed experimentally...

NMR chemical shift and J coupling parameterization and quantum mechanical reference spectrum simulation for selected nerve agent degradation products in aqueous conditions.

Science.gov (United States)

Koskela, Harri; Anđelković, Boban

2017-10-01

The spectral parameters of selected nerve agent degradation products relevant to the Chemical Weapons Convention, namely, ethyl methylphosphonate, isopropyl methylphosphonate, pinacolyl methylphosphonate and methylphosphonic acid, were studied in wide range of pH conditions and selected temperatures. The pH and temperature dependence of chemical shifts and J couplings was parameterized using Henderson-Hasselbalch-based functions. The obtained parameters allowed calculation of precise chemical shifts and J coupling constants in arbitrary pH conditions and typical measurement temperatures, thus facilitating quantum mechanical simulation of reference spectra in the chosen magnetic field strength for chemical verification. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Chemical warfare agent detection: a review of current trends and future perspective.

Science.gov (United States)

Pacsial-Ong, Eden Joy; Aguilar, Zoraida P

2013-01-01

The World Health Organization recommends countries to create a public health system that can respond to the deliberate release of chemical warfare agents (CWAs). Procedures for preparedness, response, decontamination protocols and medical countermeasures against CWA attacks are described. Known CWAs, including their properties and pharmacological consequences upon exposure, are tabulated and discussed. Requirements imposed on detection systems by various applications and environmental needs are presented in order to assess the devices for detection and identification of specific CWAs. The review surveys current and near-term detection technologies and equipments, as well as devices that are currently available to the military and civilian first responders. Brief technical discussions of several detection technologies are presented, with emphasis placed in the principles of detection. Finally, enabling technologies that form the basis for advanced sensing systems and devices are described.

Review of decontamination technologies for chemical counter-terrorism

Energy Technology Data Exchange (ETDEWEB)

Volchek, K.; Boudreau, L.; Hornof, M. [SAIC Canada, Ottawa, ON (Canada); Fingas, M.F.; Gamble, R.L. [Environment Canada, Ottawa, ON (Canada). Emergencies Science and Technology Div]|[Environment Canada, Ottawa, ON (Canada). River Road Environmental Technology Centre

2004-07-01

The two categories of chemical agents that could be used in acts of chemical terrorism are conventional chemical warfare agents and commercial toxic chemicals. Industrial chemicals are easier to access than warfare agents, and must therefore be considered when evaluating decontamination techniques. This study involved a search of public-domain documents to identify decontamination technologies including: physical/mechanical treatment or removal; chemical treatment; and, biological methods including natural degradation and attenuation. The technologies were analyzed with reference to their effectiveness for specific groups of chemical agents, state of development, availability and costs. Results indicate that there are many decontamination methods available, both developed and under development, that work effectively for most agents. The two most common decontamination methods are oxidation and alkali hydrolysis followed by dehalogenation. Technology limitations and gaps were also identified, suggesting a need for more research to further the development of promising processes. 31 refs., 2 tabs.

DNA damage induced in mouse peritoneal exudate cells after in vivo administration of chemical and physical agents as determined by alkaline elution

International Nuclear Information System (INIS)

Nishi, Yoshisuke; Miyanaga, Kumiko; Sato, Sei-ichi; Inui, Naomichi

1990-01-01

The alkaline elution technique for detecting DNA strand breaks has been applied to the study of DNA damage in mouse peritoneal exudate cells resulting from the in vivo administration of chemical and physical agents. The direct methylating agents methyl methanesulphonate and N-methyl-N-nitrosourea induced extensive breakage in samples taken 2 h after administration. The direct ethylating agents ethyl methanesulphonate and N-ethyl-N-nitrosourea also induced DNA strand breaks, but to a lesser extent than the methylating agents. The indirect methylating agent dimethylnitrosamine showed hardly any effect in this system. A weak but positive response was observed upon treatment with the anti-neoplastic alkylating agent procarbazine hydrochloride. The whole-body irradiation of mice with 60 Co γ-rays also induced DNA strand breaks. The elution profiles for γ-ray irradiation were different from those of alkylating agents, and indicate that alkylating agents produce many more secondary lesions leading to DNA strand breaks than γ-rays. N-methyl-N-nitrosourea produced slightly more DNA strand breaks in mutagen-sensitive mice, which are derived from the CD-1 strain, than in ICR mice. (Author)

DNA damage induced in mouse peritoneal exudate cells after in vivo administration of chemical and physical agents as determined by alkaline elution

Energy Technology Data Exchange (ETDEWEB)

Nishi, Yoshisuke (Japan Tobacco Inc., Yokohama (Japan). Central Research Inst.); Miyanaga, Kumiko; Sato, Sei-ichi (Japan Tobacco Inc., Hatano, Kanagawa (Japan). Toxicology Research Lab.); Inui, Naomichi (Japan Tobacco Inc., Yokohama, Kanagawa (Japan). Pharmaceutical Research Labs.)

1990-01-01

The alkaline elution technique for detecting DNA strand breaks has been applied to the study of DNA damage in mouse peritoneal exudate cells resulting from the in vivo administration of chemical and physical agents. The direct methylating agents methyl methanesulphonate and N-methyl-N-nitrosourea induced extensive breakage in samples taken 2 h after administration. The direct ethylating agents ethyl methanesulphonate and N-ethyl-N-nitrosourea also induced DNA strand breaks, but to a lesser extent than the methylating agents. The indirect methylating agent dimethylnitrosamine showed hardly any effect in this system. A weak but positive response was observed upon treatment with the anti-neoplastic alkylating agent procarbazine hydrochloride. The whole-body irradiation of mice with {sup 60}Co {gamma}-rays also induced DNA strand breaks. The elution profiles for {gamma}-ray irradiation were different from those of alkylating agents, and indicate that alkylating agents produce many more secondary lesions leading to DNA strand breaks than {gamma}-rays. N-methyl-N-nitrosourea produced slightly more DNA strand breaks in mutagen-sensitive mice, which are derived from the CD-1 strain, than in ICR mice. (Author).

Evaluation of chemical and biological agents for control of Phytophthora species on intact plants or detached leaves of rhododendron and lilac

Science.gov (United States)

R.G. Linderman; E.A. Davis

2006-01-01

The recent incidence of Ramorum blight, caused by Phytophthora ramorum, on many nursery crops has focused attention on improving management strategies against Phytophthora diseases in nurseries. We evaluated several chemical agents that target Oomycete pathogens for their capacity to inhibit infection of rhododendron or lilac...

Infectious agents are associated with psychiatric diseases

Directory of Open Access Journals (Sweden)

Daniela Lydia Krause

2012-01-01

Full Text Available There are several infectious agents in the environment that can cause persistent infections in the host. They usually cause their symptoms shortly after first infection and later persist as silent viruses and bacteria within the body. However, these chronic infections may play an important role in the pathogenesis of schizophrenia and Tourette’s syndrome (TS. We investigated the distribution of different neurotrophic infectious agents in TS, schizophrenia and controls. A total of 93 individuals were included (schizophrenic patients, Tourette patients and controls. We evaluated antibodies against cytomegalovirus (CMV, herpes-simplex virus (HSV, Epstein-Barr virus, Toxoplasma, Mycoplasma and Chlamydia trachomatis/pneumoniae. By comparing schizophrenia and TS, we found a higher prevalence of HSV (P=0.017 and CMV (P=0.017 antibodies in schizophrenic patients. Considering the relationship between schizophrenia, TS and healthy controls, we showed that there are associations for Chlamydia trachomatis (P=0.007, HSV (P=0.027 and CMV (P=0.029. When all measured viruses, bacteria and protozoa were combined, schizophrenic patients had a higher rate of antibodies to infectious agents than TS patients (P=0.049. Tourette and schizophrenic patients show a different vulnerability to infectious agents. Schizophrenic patients were found to have a higher susceptibility to viral infections than individuals with TS. This finding might point to a modification in special immune parameters in these diseases.

Research on removing reservoir core water sensitivity using the method of ultrasound-chemical agent for enhanced oil recovery.

Science.gov (United States)

Wang, Zhenjun; Huang, Jiehao

2018-04-01

The phenomenon of water sensitivity often occurs in the oil reservoir core during the process of crude oil production, which seriously affects the efficiency of oil extraction. In recent years, near-well ultrasonic processing technology attaches more attention due to its safety and energy efficient. In this paper, the comparison of removing core water sensitivity by ultrasonic wave, chemical injection and ultrasound-chemical combination technique are investigated through experiments. Results show that: lower ultrasonic frequency and higher power can improve the efficiency of core water sensitivity removal; the effects of removing core water sensitivity under ultrasonic treatment get better with increase of core initial permeability; the effect of removing core water sensitivity using ultrasonic treatment won't get better over time. Ultrasonic treatment time should be controlled in a reasonable range; the effect of removing core water sensitivity using chemical agent alone is slightly better than that using ultrasonic treatment, however, chemical injection could be replaced by ultrasonic treatment for removing core water sensitivity from the viewpoint of oil reservoir protection and the sustainable development of oil field; ultrasound-chemical combination technique has the best effect for water sensitivity removal than using ultrasonic treatment or chemical injection alone. Copyright © 2017 Elsevier B.V. All rights reserved.

Identification of an Antimicrobial Agent Effective against Methicillin-Resistant Staphylococcus aureus Persisters Using a Fluorescence-Based Screening Strategy.

Directory of Open Access Journals (Sweden)

Wooseong Kim

Full Text Available Persisters are a subpopulation of normal bacterial cells that show tolerance to conventional antibiotics. Persister cells are responsible for recalcitrant chronic infections and new antibiotics effective against persisters would be a major development in the treatment of these infections. Using the reporter dye SYTOX Green that only stains cells with permeabilized membranes, we developed a fluorescence-based screening assay in a 384-well format for identifying compounds that can kill methicillin-resistant Staphylococcus aureus (MRSA persisters. The assay proved robust and suitable for high throughput screening (Z`-factor: >0.7. In screening a library of hits from a previous screen, which identified compounds that had the ability to block killing of the nematode Caenorhabditis by MRSA, we discovered that the low molecular weight compound NH125, a bacterial histidine kinase inhibitor, kills MRSA persisters by causing cell membrane permeabilization, and that 5 μg/mL of the compound can kill all cells to the limit of detection in a 108 CFU/mL culture of MRSA persisters within 3h. Furthermore, NH125 disrupts 50% of established MRSA biofilms at 20 μg/mL and completely eradicates biofilms at 160 μg/mL. Our results suggest that the SYTOX Green screening assay is suitable for large-scale projects to identify small molecules effective against MRSA persisters and should be easily adaptable to a broad range of pathogens that form persisters. Since NH125 has strong bactericidal properties against MRSA persisters and high selectivity to bacteria, we believe NH125 is a good anti-MRSA candidate drug that should be further evaluated.

Identification of an Antimicrobial Agent Effective against Methicillin-Resistant Staphylococcus aureus Persisters Using a Fluorescence-Based Screening Strategy.

Science.gov (United States)

Kim, Wooseong; Conery, Annie L; Rajamuthiah, Rajmohan; Fuchs, Beth Burgwyn; Ausubel, Frederick M; Mylonakis, Eleftherios

2015-01-01

Persisters are a subpopulation of normal bacterial cells that show tolerance to conventional antibiotics. Persister cells are responsible for recalcitrant chronic infections and new antibiotics effective against persisters would be a major development in the treatment of these infections. Using the reporter dye SYTOX Green that only stains cells with permeabilized membranes, we developed a fluorescence-based screening assay in a 384-well format for identifying compounds that can kill methicillin-resistant Staphylococcus aureus (MRSA) persisters. The assay proved robust and suitable for high throughput screening (Z`-factor: >0.7). In screening a library of hits from a previous screen, which identified compounds that had the ability to block killing of the nematode Caenorhabditis by MRSA, we discovered that the low molecular weight compound NH125, a bacterial histidine kinase inhibitor, kills MRSA persisters by causing cell membrane permeabilization, and that 5 μg/mL of the compound can kill all cells to the limit of detection in a 108 CFU/mL culture of MRSA persisters within 3h. Furthermore, NH125 disrupts 50% of established MRSA biofilms at 20 μg/mL and completely eradicates biofilms at 160 μg/mL. Our results suggest that the SYTOX Green screening assay is suitable for large-scale projects to identify small molecules effective against MRSA persisters and should be easily adaptable to a broad range of pathogens that form persisters. Since NH125 has strong bactericidal properties against MRSA persisters and high selectivity to bacteria, we believe NH125 is a good anti-MRSA candidate drug that should be further evaluated.

Chemical characterization and ecotoxicity of three soil foaming agents used in mechanized tunneling.

Science.gov (United States)

Baderna, Diego; Lomazzi, Eleonora; Passoni, Alice; Pogliaghi, Alberto; Petoumenou, Maria Ifigeneia; Bagnati, Renzo; Lodi, Marco; Viarengo, Aldo; Sforzini, Susanna; Benfenati, Emilio; Fanelli, Roberto

2015-10-15

The construction of tunnels and rocks with mechanized drills produces several tons of rocky debris that are today recycled as construction material or as soil replacement for covering rocky areas. The lack of accurate information about the environmental impact of these excavated rocks and foaming agents added during the excavation process has aroused increasing concern for ecosystems and human health. The present study proposes an integrated approach to the assessment of the potential environmental impact of three foaming agents containing different anionic surfactants and other polymers currently on the market and used in tunnel boring machines. The strategy includes chemical characterization with high resolution mass spectrometry techniques to identify the components of each product, the use of in silico tools to perform a similarity comparison among these compounds and some pollutants already listed in regulatory frameworks to identify possible threshold concentrations of contamination, and the application of a battery of ecotoxicological assays to investigate the impact of each foaming mixture on model organisms of soil (higher plants and Eisenia andrei) and water communities (Daphnia magna). The study identified eleven compounds not listed on the material safety data sheets for which we have identified possible concentrations of contamination based on existing regulatory references. The bioassays allowed us to determine the no effect concentrations (NOAECs) of the three mixtures, which were subsequently used as threshold concentration for the product in its entirety. The technical mixtures used in this study have a different degree of toxicity and the predicted environmental concentrations based on the conditions of use are lower than the NOAEC for soils but higher than the NOAEC for water, posing a potential risk to the waters due to the levels of foaming agents in the muck. Copyright © 2015 Elsevier B.V. All rights reserved.

Comparison of 6-thioguanine-resistant mutation and sister chromatid exchanges in Chinese hamster V79 cells with forty chemical and physical agents

International Nuclear Information System (INIS)

Nishi, Y.; Hasegawa, M.M.; Taketomi, M.; Ohkawa, Y.; Inui, N.

1984-01-01

The induction of sister chromatid exchanges (SCE) and mutation at the hypoxanthine-guanine phosphoribosyl transferase locus and toxicities of 40 different chemical and physical agents were examined on Chinese hamster V79 cells. These agents included mono-, di-, tri-, and polyfunctional alkylating agents, intercalators, gamma-rays, and UV light irradiation. Mutation was measured as resistance to 6-thioguanine and toxicity as loss of cell-plating efficiency. SCE were examined 29 hr after treatment. With the agents examined, a highly positive correlation existed between SCE-inducing and mutagenic potencies, when expressed as increase in the number per a unit dose over the control values. But the great difference of the ratios of mutagenic potencies versus SCE-inducing potencies among agents was observed, the maximal difference in the ratios being about 200-fold. The agents that showed the higher values of the ratio (agents producing more mutations than SCE) were bleomycin, cobalt-60 gamma-rays, all ethylating agents (N-ethyl-N-nitrosourea, N-ethyl-N'-nitro-N-nitrosoguanidine, ethyl methanesulfonate, and diethylsulfate), N-propyl-N-nitrosourea, N-butyl-N-nitrosourea, isopropyl methanesulfonate, intercalating acridine compounds (2-methoxy-6-chloro-9-[3-(ethyl-2-chloroethyl)aminopropylamino]-acridine X 2HCl and 2-methoxy-6-chloro-9-[3-(chloroethyl)-aminopropylamino]acridine 2HCl) and UV light at 254 nm

Domestic Preparedness Program: Evaluation of the Agilent Gas Chromatograph - Flame Photometric Detector/Mass Selective Detector (GC-FPD/MSD) System Against Chemical Warfare Agents Summary Report

National Research Council Canada - National Science Library

Longworth, Terri

2003-01-01

This report characterizes the chemical warfare agent (CWA) detection potential of the commercially available Agilent gas chromatograph-flame photometric detector/mass selective detector (GC-FPD/MSD...

Parameters for the Evaluation of the Fate, Transport, and Environmental Impacts of Chemical Agents in Marine Environments

Science.gov (United States)

2007-07-01

Anal. Bering/Chukchi, accessed 3 January 2007, http://www.osdpd.noaa.gov/PSB/EPS/SST/data/beringst.c.gif. RE-2 15 Brewer , P. G.; Glover, D. M...Highly Purified Mustard Gas and its Action on Yeast , ” J. Am. Chem. Soc., 1947, 69(7), 1808-1809. 135 Redemann, C. E.; Chaikin, S. W.; Fearing, R. B...171 MacNaughton, M. G.; Brewer , J. H., Environmental Chemistry and Fate of Chemical Warfare Agents, Southwest Research Institute, San Antonio TX, 1994

Explosives and chemical warfare agents - detection and analysis with PTR-MS

Energy Technology Data Exchange (ETDEWEB)

Sulzer, Philipp; Juerschik, Simone; Jaksch, Stefan; Jordan, Alfons; Hanel, Gernot; Hartungen, Eugen; Seehauser, Hans; Maerk, Lukas; Haidacher, Stefan; Schottkowsky, Ralf [IONICON Analytik GmbH, Innsbruck (Austria); Petersson, Fredrik [Institut fuer Ionenphysik und Angewandte Physik, Leopold-Franzens Universitaet Innsbruck (Austria); Maerk, Tilmann [IONICON Analytik GmbH, Innsbruck (Austria); Institut fuer Ionenphysik und Angewandte Physik, Leopold-Franzens Universitaet Innsbruck (Austria)

2010-07-01

We utilized a recently developed high sensitivity PTR-MS instrument equipped with a high resolution time-of-flight mass analyzer for detailed investigations on explosives and chemical warfare agents (CWAs). We show that with this so called PTR-TOF 8000 it is possible to identify solid explosives (RDX, TNT, HMX, PETN and Semtex A) by analyzing the headspace above small quantities of samples at room temperature and from trace quantities not visible to the naked eye placed on surfaces. As the mentioned solid explosives possess very low vapor pressures, the main challenge for detecting them in the gas phase is to provide an instrument with a sufficient sensitivity. CWAs on the other side have very high vapor pressures but are difficult to identify unambiguously as their nominal molecular masses are usually comparably small and therefore hard to distinguish from harmless everyday-compounds (e.g. mustard gas: 159 g/mol). In the present work we demonstrate that we can detect a broad range of dangerous substances, ranging from the CWA mustard gas to the explosive HMX.

Fate of the chemical warfare agent O-ethyl S-2-diisopropylaminoethyl methylphosphonothiolate (VX) on soil following accelerant-based fire and liquid decontamination.

Science.gov (United States)

Gravett, M R; Hopkins, F B; Self, A J; Webb, A J; Timperley, C M; Riches, J R

2014-08-01

In the event of alleged use of organophosphorus nerve agents, all kinds of environmental samples can be received for analysis. These might include decontaminated and charred matter collected from the site of a suspected chemical attack. In other scenarios, such matter might be sampled to confirm the site of a chemical weapon test or clandestine laboratory decontaminated and burned to prevent discovery. To provide an analytical capability for these contingencies, we present a preliminary investigation of the effect of accelerant-based fire and liquid decontamination on soil contaminated with the nerve agent O-ethyl S-2-diisopropylaminoethyl methylphosphonothiolate (VX). The objectives were (a) to determine if VX or its degradation products were detectable in soil after an accelerant-based fire promoted by aviation fuel, including following decontamination with Decontamination Solution 2 (DS2) or aqueous sodium hypochlorite, (b) to develop analytical methods to support forensic analysis of accelerant-soaked, decontaminated and charred soil and (c) to inform the design of future experiments of this type to improve analytical fidelity. Our results show for the first time that modern analytical techniques can be used to identify residual VX and its degradation products in contaminated soil after an accelerant-based fire and after chemical decontamination and then fire. Comparison of the gas chromatography-mass spectrometry (GC-MS) profiles of VX and its impurities/degradation products from contaminated burnt soil, and burnt soil spiked with VX, indicated that the fire resulted in the production of diethyl methylphosphonate and O,S-diethyl methylphosphonothiolate (by an unknown mechanism). Other products identified were indicative of chemical decontamination, and some of these provided evidence of the decontaminant used, for example, ethyl 2-methoxyethyl methylphosphonate and bis(2-methoxyethyl) methylphosphonate following decontamination with DS2. Sample preparation

Persistent Organic Pollutants as Risk Factors for Obesity and Diabetes.

Science.gov (United States)

Yang, Chunxue; Kong, Alice Pik Shan; Cai, Zongwei; Chung, Arthur C K

2017-11-02

The rising prevalence of obesity and diabetes cannot be fully explained by known risk factors, such as unhealthy diet, a sedentary lifestyle, and family history. This review summarizes the available studies linking persistent organic pollutants (POPs) to obesity and diabetes and discusses plausible underlying mechanisms. Increasing evidence suggest that POPs may act as obesogens and diabetogens to promote the development of obesity and diabetes and induce metabolic dysfunction. POPs are synthesized chemicals and are used widely in our daily life. These chemicals are resistant to degradation in chemical or biological processes, which enable them to exist in the environment persistently and to be bio-accumulated in animal and human tissue through the food chain. Increasingly, epidemiologic studies suggest a positive association between POPs and risk of developing diabetes. Understanding the relationship of POPs with obesity and diabetes may shed light on preventive strategies for obesity and diabetes.

Report of National Cancer Institute symposium: comparison of mechanisms of carcinogenesis by radiation and chemical agents. I. Common molecular mechanisms

International Nuclear Information System (INIS)

Borg, D.C.

1984-01-01

Some aspects of molecular mechanisms common to radiation and chemical carcinogenesis are discussed, particularly the DNA damage done by these agents. Emphasis is placed on epidemiological considerations and on dose-response models used in risk assessment to extrapolate from experimental data obtained at high doses to the effects from long-term, low-level exposures. 3 references, 6 figures

Report of National Cancer Institute symposium: comparison of mechanisms of carcinogenesis by radiation and chemical agents. I. Common molecular mechanisms

Energy Technology Data Exchange (ETDEWEB)

Borg, D.C.

1984-01-01

Some aspects of molecular mechanisms common to radiation and chemical carcinogenesis are discussed, particularly the DNA damage done by these agents. Emphasis is placed on epidemiological considerations and on dose-response models used in risk assessment to extrapolate from experimental data obtained at high doses to the effects from long-term, low-level exposures. 3 references, 6 figures. (ACR)

Treating exposure to chemical warfare agents: implications for health care providers and community emergency planning.

Science.gov (United States)

Munro, N B; Watson, A P; Ambrose, K R; Griffin, G D

1990-01-01

Current treatment protocols for exposure to nerve and vesicant agents found in the U.S. stockpile of unitary chemical weapons are summarized, and the toxicities of available antidotes are evaluated. The status of the most promising of the new nerve agent antidotes is reviewed. In the U.S. atropine and pralidoxime compose the only approved antidote regimen for organophosphate nerve agent poisoning. Diazepam may also be used if necessary to control convulsions. To avoid death, administration must occur within minutes of substantial exposure together with immediate decontamination. Continuous observation and repeated administration of antidotes are necessary as symptoms warrant. Available antidotes do not necessarily prevent respiratory failure or incapacitation. The toxicity of the antidotes themselves and the individualized nature of medical care preclude recommending that autoinjectors be distributed to the general public. In addition, precautionary administration of protective drugs to the general population would not be feasible or desirable. No antidote exists for poisoning by the vesicant sulfur mustard (H, HD, HT); effective intervention can only be accomplished by rapid decontamination followed by palliative treatment of symptoms. British anti-Lewisite (BAL) (2,3-dimercapto-1-propanolol) is the antidote of choice for treatment of exposure to Lewisite, another potent vesicant. Experimental water-soluble BAL analogues have been developed that are less toxic than BAL. Treatment protocols for each antidote are summarized in tabular form for use by health care providers. PMID:2088748

Graphene Nanoplatelet-Polymer Chemiresistive Sensor Arrays for the Detection and Discrimination of Chemical Warfare Agent Simulants.

Science.gov (United States)

Wiederoder, Michael S; Nallon, Eric C; Weiss, Matt; McGraw, Shannon K; Schnee, Vincent P; Bright, Collin J; Polcha, Michael P; Paffenroth, Randy; Uzarski, Joshua R

2017-11-22

A cross-reactive array of semiselective chemiresistive sensors made of polymer-graphene nanoplatelet (GNP) composite coated electrodes was examined for detection and discrimination of chemical warfare agents (CWA). The arrays employ a set of chemically diverse polymers to generate a unique response signature for multiple CWA simulants and background interferents. The developed sensors' signal remains consistent after repeated exposures to multiple analytes for up to 5 days with a similar signal magnitude across different replicate sensors with the same polymer-GNP coating. An array of 12 sensors each coated with a different polymer-GNP mixture was exposed 100 times to a cycle of single analyte vapors consisting of 5 chemically similar CWA simulants and 8 common background interferents. The collected data was vector normalized to reduce concentration dependency, z-scored to account for baseline drift and signal-to-noise ratio, and Kalman filtered to reduce noise. The processed data was dimensionally reduced with principal component analysis and analyzed with four different machine learning algorithms to evaluate discrimination capabilities. For 5 similarly structured CWA simulants alone 100% classification accuracy was achieved. For all analytes tested 99% classification accuracy was achieved demonstrating the CWA discrimination capabilities of the developed system. The novel sensor fabrication methods and data processing techniques are attractive for development of sensor platforms for discrimination of CWA and other classes of chemical vapors.

On the causes of persistent apical periodontitis: a review.

Science.gov (United States)

Nair, P N R

2006-04-01

Apical periodontitis is a chronic inflammatory disorder of periradicular tissues caused by aetiological agents of endodontic origin. Persistent apical periodontitis occurs when root canal treatment of apical periodontitis has not adequately eliminated intraradicular infection. Problems that lead to persistent apical periodontitis include: inadequate aseptic control, poor access cavity design, missed canals, inadequate instrumentation, debridement and leaking temporary or permanent restorations. Even when the most stringent procedures are followed, apical periodontitis may still persist as asymptomatic radiolucencies, because of the complexity of the root canal system formed by the main and accessory canals, their ramifications and anastomoses where residual infection can persist. Further, there are extraradicular factors -- located within the inflamed periapical tissue -- that can interfere with post-treatment healing of apical periodontitis. The causes of apical periodontitis persisting after root canal treatment have not been well characterized. During the 1990s, a series of investigations have shown that there are six biological factors that lead to asymptomatic radiolucencies persisting after root canal treatment. These are: (i) intraradicular infection persisting in the complex apical root canal system; (ii) extraradicular infection, generally in the form of periapical actinomycosis; (iii) extruded root canal filling or other exogenous materials that cause a foreign body reaction; (iv) accumulation of endogenous cholesterol crystals that irritate periapical tissues; (v) true cystic lesions, and (vi) scar tissue healing of the lesion. This article provides a comprehensive overview of the causative factors of non-resolving periapical lesions that are seen as asymptomatic radiolucencies post-treatment.

A theory of chemicals regulation and testing

NARCIS (Netherlands)

Gabbert, S.G.M.; Weikard, H.P.

2010-01-01

Risk management of chemicals requires information about their adverse effects such as toxicity and persistence, for example. Testing of chemicals allows for improving the information base for regulatory decision-making on chemicals' production and use. Testing a large number of chemicals with

Mustard gas or sulfur mustard: an old chemical agent as a new terrorist threat.

Science.gov (United States)

Wattana, Monica; Bey, Tareg

2009-01-01

Sulfur mustard is a member of the vesicant class of chemical warfare agents that causes blistering to the skin and mucous membranes. There is no specific antidote, and treatment consists of systematically alleviating symptoms. Historically, sulfur mustard was used extensively in inter-governmental conflicts within the trenches of Belgium and France during World War I and during the Iran-Iraq conflict. Longitudinal studies of exposed victims show that sulfur mustard causes long-term effects leading to high morbidity. Given that only a small amount of sulfur mustard is necessary to potentially cause an enormous number of casualties, disaster-planning protocol necessitates the education and training of first-line healthcare responders in the recognition, decontamination, triage, and treatment of sulfur mustard-exposed victims in a large-scale scenario.

Comparison of Three Sample Preparation Methods for Analysis of Chemical Warfare Agent Stimulants in Water

International Nuclear Information System (INIS)

Alessandro Sassolini

2015-01-01

Analytical chemistry in CBRNe (Chemical Biological Radiological Nuclear explosive) context requires not only high quality data; quickness, ruggedness and robustness are also mandatory. In this work, three samples preparation methods were compared using several organophosphorus pesticides as test compounds, used as stimulants of nerve CWA (Chemical Warfare Agents) to choose the one with best characteristics. Result was obtained better with the Dispersive Liquid-Liquid Micro Extraction (DLLME), relatively new in CBRNe field, obtaining uncertainty for different simulants between 8 and 15 % while a quantification limit between 0.01 and 0.08 μg/ l. To optimize this extraction method, different organo chlorinated solvents also tested but not relevant difference in these tests was obtained. In this work, all samples were analyzed by using a gas chromatography coupled with mass spectrometer (GC-MS) and also with Gas Chromatograph coupled with Nitrogen Phosphorous Detector (NPD) for DLLME samples to evaluate a low cost and rugged instrument adapt to field analytical methods with good performance in terms of uncertainty and sensibility even if poorer respect to the mass spectrometry. (author)

Chemical reagent and process for refuse disposal

International Nuclear Information System (INIS)

Somerville, R.B.; Fan, L.T.

1989-01-01

A process for treating refuse by mixing them with a reactive chemical and a puzzolana-type material. Said chemical includes a retarding agent which modifies the viscosity and an accelerating agent. (author)

Identification of vapor-phase chemical warfare agent simulants and rocket fuels using laser-induced breakdown spectroscopy

International Nuclear Information System (INIS)

Stearns, Jaime A.; McElman, Sarah E.; Dodd, James A.

2010-01-01

Application of laser-induced breakdown spectroscopy (LIBS) to the identification of security threats is a growing area of research. This work presents LIBS spectra of vapor-phase chemical warfare agent simulants and typical rocket fuels. A large dataset of spectra was acquired using a variety of gas mixtures and background pressures and processed using partial least squares analysis. The five compounds studied were identified with a 99% success rate by the best method. The temporal behavior of the emission lines as a function of chamber pressure and gas mixture was also investigated, revealing some interesting trends that merit further study.

Identification of vapor-phase chemical warfare agent simulants and rocket fuels using laser-induced breakdown spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Stearns, Jaime A.; McElman, Sarah E.; Dodd, James A.

2010-05-01

Application of laser-induced breakdown spectroscopy (LIBS) to the identification of security threats is a growing area of research. This work presents LIBS spectra of vapor-phase chemical warfare agent simulants and typical rocket fuels. A large dataset of spectra was acquired using a variety of gas mixtures and background pressures and processed using partial least squares analysis. The five compounds studied were identified with a 99% success rate by the best method. The temporal behavior of the emission lines as a function of chamber pressure and gas mixture was also investigated, revealing some interesting trends that merit further study.

Predicting degradability of organic chemicals

Energy Technology Data Exchange (ETDEWEB)

Finizio, A; Vighi, M [Milan Univ. (Italy). Ist. di Entomologia Agraria

1992-05-01

Degradability, particularly biodegradability, is one of the most important factors governing the persistence of pollutants in the environment and consequently influencing their behavior and toxicity in aquatic and terrestrial ecosystems. The need for reliable persistence data in order to assess the environmental fate and hazard of chemicals by means of predictive approaches, is evident. Biodegradability tests are requested by the EEC directive on new chemicals. Neverthless, degradation tests are not easy to carry out and data on existing chemicals are very scarce. Therefore, assessing the fate of chemicals in the environment from the simple study of their structure would be a useful tool. Rates of degradation are a function of the rates of a series of processes. Correlation between degradation rates and structural parameters are will be facilitated if one of the processes is rate determining. This review is a survey of studies dealing with relationships between structure and biodegradation of organic chemicals, to identify the value and limitations of this approach.

Broad-Spectrum Liquid- and Gas-Phase Decontamination of Chemical Warfare Agents by One-Dimensional Heteropolyniobates.

Science.gov (United States)

Guo, Weiwei; Lv, Hongjin; Sullivan, Kevin P; Gordon, Wesley O; Balboa, Alex; Wagner, George W; Musaev, Djamaladdin G; Bacsa, John; Hill, Craig L

2016-06-20

A wide range of chemical warfare agents and their simulants are catalytically decontaminated by a new one-dimensional polymeric polyniobate (P-PONb), K12 [Ti2 O2 ][GeNb12 O40 ]⋅19 H2 O (KGeNb) under mild conditions and in the dark. Uniquely, KGeNb facilitates hydrolysis of nerve agents Sarin (GB) and Soman (GD) (and their less reactive simulants, dimethyl methylphosphonate (DMMP)) as well as mustard (HD) in both liquid and gas phases at ambient temperature and in the absence of neutralizing bases or illumination. Three lines of evidence establish that KGeNb removes DMMP, and thus likely GB/GD, by general base catalysis: a) the k(H2 O)/k(D2 O) solvent isotope effect is 1.4; b) the rate law (hydrolysis at the same pH depends on the amount of P-PONb present); and c) hydroxide is far less active against the above simulants at the same pH than the P-PONbs themselves, a critical control experiment. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Physical and chemical stability of proflavine contrast agent solutions for early detection of oral cancer.

Science.gov (United States)

Kawedia, Jitesh D; Zhang, Yan-Ping; Myers, Alan L; Richards-Kortum, Rebecca R; Kramer, Mark A; Gillenwater, Ann M; Culotta, Kirk S

2016-02-01

Proflavine hemisulfate solution is a fluorescence contrast agent to visualize cell nuclei using high-resolution optical imaging devices such as the high-resolution microendoscope. These devices provide real-time imaging to distinguish between normal versus neoplastic tissue. These images could be helpful for early screening of oral cancer and its precursors and to determine accurate margins of malignant tissue for ablative surgery. Extemporaneous preparation of proflavine solution for these diagnostic procedures requires preparation in batches and long-term storage to improve compounding efficiency in the pharmacy. However, there is a paucity of long-term stability data for proflavine contrast solutions. The physical and chemical stability of 0.01% (10 mg/100 ml) proflavine hemisulfate solutions prepared in sterile water was determined following storage at refrigeration (4-8℃) and room temperature (23℃). Concentrations of proflavine were measured at predetermined time points up to 12 months using a validated stability-indicating high-performance liquid chromatography method. Proflavine solutions stored under refrigeration were physically and chemically stable for at least 12 months with concentrations ranging from 95% to 105% compared to initial concentration. However, in solutions stored at room temperature increased turbidity and particulates were observed in some of the tested vials at 9 months and 12 months with peak particle count reaching 17-fold increase compared to baseline. Solutions stored at room temperature were chemically stable up to six months (94-105%). Proflavine solutions at concentration of 0.01% were chemically and physically stable for at least 12 months under refrigeration. The solution was chemically stable for six months when stored at room temperature. We recommend long-term storage of proflavine solutions under refrigeration prior to diagnostic procedure. © The Author(s) 2014.

Binding affinity and decontamination of dermal decontamination gel to model chemical warfare agent simulants.

Science.gov (United States)

Cao, Yachao; Elmahdy, Akram; Zhu, Hanjiang; Hui, Xiaoying; Maibach, Howard

2018-05-01

Six chemical warfare agent simulants (trimethyl phosphate, dimethyl adipate, 2-chloroethyl methyl sulfide, diethyl adipate, chloroethyl phenyl sulfide and diethyl sebacate) were studied in in vitro human skin to explore relationship between dermal penetration/absorption and the mechanisms of simulant partitioning between stratum corneum (SC) and water as well as between dermal decontamination gel (DDGel) and water. Both binding affinity to and decontamination of simulants using DDGel were studied. Partition coefficients of six simulants between SC and water (Log P SC/w ) and between DDGel and water (Log P DDGel/w ) were determined. Results showed that DDGel has a similar or higher binding affinity to each simulant compared to SC. The relationship between Log P octanol/water and Log P SC/w as well as between Log P octanol/water and Log P DDGel/w demonstrated that partition coefficient of simulants correlated to their lipophilicity or hydrophilicity. Decontamination efficiency results with DDGel for these simulants were consistent with binding affinity results. Amounts of percentage dose of chemicals in DDGel of trimethyl phosphate, dimethyl adipate, 2-chloroethyl methyl sulfide, diethyl adipate, chloroethyl phenyl sulfide and diethyl sebacate were determined to be 61.15, 85.67, 75.91, 53.53, 89.89 and 76.58, with corresponding amounts absorbed in skin of 0.96, 0.65, 1.68, 0.72, 0.57 and 1.38, respectively. In vitro skin decontamination experiments coupled with a dermal absorption study demonstrated that DDGel can efficiently remove chemicals from skin surface, back-extract from the SC, and significantly reduced chemical penetration into skin or systemic absorption for all six simulants tested. Therefore, DDGel offers a great potential as a NextGen skin Decon platform technology for both military and civilian use. Copyright © 2018 John Wiley & Sons, Ltd.

ANALYSIS AND IDENTIFICATION SPIKING CHEMICAL COMPOUNDS RELATED TO CHEMICAL WEAPON CONVENTION IN UNKNOWN WATER SAMPLES USING GAS CHROMATOGRAPHY AND GAS CHROMATOGRAPHY ELECTRON IONIZATION MASS SPECTROMETRY

Directory of Open Access Journals (Sweden)

Harry Budiman

2010-06-01

Full Text Available The identification and analysis of chemical warfare agents and their degradation products is one of important component for the implementation of the convention. Nowadays, the analytical method for determination chemical warfare agent and their degradation products has been developing and improving. In order to get the sufficient analytical data as recommended by OPCW especially in Proficiency Testing, the spiking chemical compounds related to Chemical Weapon Convention in unknown water sample were determined using two different techniques such as gas chromatography and gas chromatography electron-impact ionization mass spectrometry. Neutral organic extraction, pH 11 organic extraction, cation exchanged-methylation, triethylamine/methanol-silylation were performed to extract the chemical warfare agents from the sample, before analyzing with gas chromatography. The identification of chemical warfare agents was carried out by comparing the mass spectrum of chemicals with mass spectrum reference from the OPCW Central Analytical Database (OCAD library while the retention indices calculation obtained from gas chromatography analysis was used to get the confirmation and supported data of  the chemical warfare agents. Diisopropyl methylphosphonate, 2,2-diphenyl-2-hydroacetic acid and 3-quinuclidinol were found in unknown water sample. Those chemicals were classified in schedule 2 as precursor or reactant of chemical weapons compound in schedule list of Chemical Weapon Convention.   Keywords: gas chromatography, mass spectrometry, retention indices, OCAD library, chemical warfare agents

Identification of Additional Anti-Persister Activity against Borrelia burgdorferi from an FDA Drug Library

Directory of Open Access Journals (Sweden)

Jie Feng

2015-09-01

Full Text Available Lyme disease is a leading vector-borne disease in the United States. Although the majority of Lyme patients can be cured with standard 2–4 week antibiotic treatment, 10%–20% of patients continue to suffer from prolonged post-treatment Lyme disease syndrome (PTLDS. While the cause for this is unclear, persisting organisms not killed by current Lyme antibiotics may be involved. In our previous study, we screened an FDA drug library and reported 27 top hits that showed high activity against Borrelia persisters. In this study, we present the results of an additional 113 active hits that have higher activity against the stationary phase B. burgdorferi than the currently used Lyme antibiotics. Many antimicrobial agents (antibiotics, antivirals, antifungals, anthelmintics or antiparasitics used for treating other infections were found to have better activity than the current Lyme antibiotics. These include antibacterials such as rifamycins (3-formal-rifamycin, rifaximin, rifamycin SV, thiostrepton, quinolone drugs (sarafloxacin, clinafloxacin, tosufloxacin, and cell wall inhibitors carbenicillin, tazobactam, aztreonam; antifungal agents such as fluconazole, mepartricin, bifonazole, climbazole, oxiconazole, nystatin; antiviral agents zanamivir, nevirapine, tilorone; antimalarial agents artemisinin, methylene blue, and quidaldine blue; antihelmintic and antiparasitic agents toltrazuril, tartar emetic, potassium antimonyl tartrate trihydrate, oxantel, closantel, hycanthone, pyrimethamine, and tetramisole. Interestingly, drugs used for treating other non-infectious conditions including verteporfin, oltipraz, pyroglutamic acid, pidolic acid, and dextrorphan tartrate, that act on the glutathione/γ-glutamyl pathway involved in protection against free radical damage, and also the antidepressant drug indatraline, were found to have high activity against stationary phase B. burgdorferi. Among the active hits, agents that affect cell membranes, energy

Identification of Additional Anti-Persister Activity against Borrelia burgdorferi from an FDA Drug Library.

Science.gov (United States)

Feng, Jie; Weitner, Megan; Shi, Wanliang; Zhang, Shuo; Sullivan, David; Zhang, Ying

2015-09-16

Lyme disease is a leading vector-borne disease in the United States. Although the majority of Lyme patients can be cured with standard 2-4 week antibiotic treatment, 10%-20% of patients continue to suffer from prolonged post-treatment Lyme disease syndrome (PTLDS). While the cause for this is unclear, persisting organisms not killed by current Lyme antibiotics may be involved. In our previous study, we screened an FDA drug library and reported 27 top hits that showed high activity against Borrelia persisters. In this study, we present the results of an additional 113 active hits that have higher activity against the stationary phase B. burgdorferi than the currently used Lyme antibiotics. Many antimicrobial agents (antibiotics, antivirals, antifungals, anthelmintics or antiparasitics) used for treating other infections were found to have better activity than the current Lyme antibiotics. These include antibacterials such as rifamycins (3-formal-rifamycin, rifaximin, rifamycin SV), thiostrepton, quinolone drugs (sarafloxacin, clinafloxacin, tosufloxacin), and cell wall inhibitors carbenicillin, tazobactam, aztreonam; antifungal agents such as fluconazole, mepartricin, bifonazole, climbazole, oxiconazole, nystatin; antiviral agents zanamivir, nevirapine, tilorone; antimalarial agents artemisinin, methylene blue, and quidaldine blue; antihelmintic and antiparasitic agents toltrazuril, tartar emetic, potassium antimonyl tartrate trihydrate, oxantel, closantel, hycanthone, pyrimethamine, and tetramisole. Interestingly, drugs used for treating other non-infectious conditions including verteporfin, oltipraz, pyroglutamic acid, pidolic acid, and dextrorphan tartrate, that act on the glutathione/γ-glutamyl pathway involved in protection against free radical damage, and also the antidepressant drug indatraline, were found to have high activity against stationary phase B. burgdorferi. Among the active hits, agents that affect cell membranes, energy production, and reactive

Bioaccumulation of chemical warfare agents, energetic materials, and metals in deep-sea shrimp from discarded military munitions sites off Pearl Harbor

Science.gov (United States)

Koide, Shelby; Silva, Jeff A. K.; Dupra, Vilma; Edwards, Margo

2016-06-01

The bioaccumulation of munitions-related chemicals at former military deep-water disposal sites is poorly understood. This paper presents the results of human-food-item biota sampling to assess the potential for bioaccumulation of chemical warfare agents, energetic materials, arsenic, and additional munitions-related metals in deep-sea shrimp tissue samples collected during the Hawai'i Undersea Military Munitions Assessment (HUMMA) project to date. The HUMMA investigation area is located within a former munitions sea-disposal site located south of Pearl Harbor on the island of O'ahu, Hawai'i, designated site Hawaii-05 (HI-05) by the United States Department of Defense. Indigenous deep-sea shrimp (Heterocarpus ensifer) were caught adjacent to discarded military munitions (DMM) and at control sites where munitions were absent. Tissue analysis results showed that chemical warfare agents and their degradation products were not present within the edible portions of these samples at detectable concentrations, and energetic materials and their degradation products were detected in only a few samples at concentrations below the laboratory reporting limits. Likewise, arsenic, copper, and lead concentrations were below the United States Food and Drug Administration's permitted concentrations of metals in marine biota tissue (if defined), and their presence within these samples could not be attributed to the presence of DMM within the study area based on a comparative analysis of munitions-adjacent and control samples collected. Based on this current dataset, it can be concluded that DMM existing within the HUMMA study area is not contributing to the bioaccumulation of munitions-related chemicals for the biota species investigated to date.

Reactions of CW Agents HD And GD with the Polymer Fabrics PVAM and CHEMCAT 41

Science.gov (United States)

2015-09-01

D. Durst, “Qualitative Gas Chromatographic Characterization of Chemically Neutralized Chemical Warfare Agent Reaction Masses Produced During...based catalysts for decontamination of HD and G agents,” Proceedings of the 2003 Joint Service Scientific Conference on Chemical & Biological...thermal burden on the wearer by allowing heat and moisture transport. The garment prevents exposure to outside chemical weapons agents (CWAs) by a

A Multifunctional Biomaterial with NIR Long Persistent Phosphorescence, Photothermal Response and Magnetism.

Science.gov (United States)

Wu, Yiling; Li, Yang; Qin, Xixi; Qiu, Jianrong

2016-09-20

There are many reports on long persistent phosphors (LPPs) applied in bioimaging. However, there are few reports on LPPs applied in photothermal therapy (PTT), and an integrated system with multiple functions of diagnosis and therapy. In this work, we fabricate effective multifunctional phosphors Zn3 Ga2 SnO8 : Cr(3+) , Nd(3+) , Gd(3+) with NIR persistent phosphorescence, photothermal response and magnetism. Such featured materials can act as NIR optical biolabels and magnetic resonance imaging (MRI) contrast agents for tracking the early cancer cells, but also as photothermal therapeutic agent for killing the cancer cells. This new multifunctional biomaterial is expected to open a new possibility of setting up an advanced imaging-guided therapy system featuring a high resolution for bioimaging and low side effects for the photothermal ablation of tumors. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Handbook of toxicology of chemical warfare agents

CERN Document Server

2010-01-01

This groundbreaking book covers every aspect of deadly toxic chemicals used as weapons of mass destruction and employed in conflicts, warfare and terrorism. Including findings from experimental as well as clinical studies, this one-of-a-kind handbook is prepared in a very user- friendly format that can easily be followed by students, teachers and researchers, as well as lay people. Stand-alone chapters on individual chemicals and major topics allow the reader to easily access required information without searching through the entire book. This is the first book that offers in-depth coverage of individual toxicants, target organ toxicity, major incidents, toxic effects in humans, animals and wildlife, biosensors, biomarkers, on-site and laboratory analytical methods, decontamination and detoxification procedures, prophylactic, therapeutic and countermeasures, and the role of homeland security. Presents a comprehensive look at all aspects of chemical warfare toxicology in one reference work. This saves research...

Polypropylenes foam consisting of thermally expandable microcapsule as blowing agent

Science.gov (United States)

Jeoung, Sun Kyung; Hwang, Ye Jin; Lee, Hyun Wook; Kwak, Sung Bok; Han, In-Soo; Ha, Jin Uk

2016-03-01

The structure of thermally expandable microcapsule (TEMs) is consisted of a thermoplastic shell which is filled with liquid hydrocarbon at core. The shell of TEMs becomes soft when the temperature is higher than boiling temperature of liquid hydrocarbon. The shell of TEMs is expanded under the high temperature because the inner pressure of TEMs is increased by vaporization of hydrocarbon core. Therefore, the TEMs are applicable for blowing agents and light weight fillers. In this research, we fabricated the polypropylene (PP) foam by using the TEMs and chemical blowing agents and compared to their physical properties. The density of the specimen was decreased when the contents of chemical blowing agents and TEMs were increased. In addition, the mechanical properties (i.e. tensile strength and impact strength) of specimens were deteriorated with increasing amount of chemical blowing agents and TEMs. However, PP foam produced with TEMs showed higher impact strength than the one with the chemical blowing agent. In order to clarify the dependence of impact strength of PP foam as the blowing agent, the morphology difference of the PP foams was investigated. Expanding properties of PP foams produced with TEMs was changed with TEMs content of PP foams. Processing conditions also influenced the mechanical properties of PP foam containing TEMs.

Towards a proportionality assessment of risk reduction measures aimed at restricting the use of persistent and bioaccumulative substances.

NARCIS (Netherlands)

Oosterhuis, Frans; Brouwer, Roy; Janssen, Martien; Verhoeven, Julia; Luttikhuizen, Cees

2017-01-01

International chemicals legislation aims at adequately controlling persistent organic pollutants (POPs) and substances of very high concern (SVHCs), such as persistent, bioaccumulative, and toxic (PBT) and very persistent and very bioaccumulative (vPvB) substances, with a view to progressively

Bridging the gap between sample collection and laboratory analysis: using dried blood spots to identify human exposure to chemical agents

Science.gov (United States)

Hamelin, Elizabeth I.; Blake, Thomas A.; Perez, Jonas W.; Crow, Brian S.; Shaner, Rebecca L.; Coleman, Rebecca M.; Johnson, Rudolph C.

2016-05-01

Public health response to large scale chemical emergencies presents logistical challenges for sample collection, transport, and analysis. Diagnostic methods used to identify and determine exposure to chemical warfare agents, toxins, and poisons traditionally involve blood collection by phlebotomists, cold transport of biomedical samples, and costly sample preparation techniques. Use of dried blood spots, which consist of dried blood on an FDA-approved substrate, can increase analyte stability, decrease infection hazard for those handling samples, greatly reduce the cost of shipping/storing samples by removing the need for refrigeration and cold chain transportation, and be self-prepared by potentially exposed individuals using a simple finger prick and blood spot compatible paper. Our laboratory has developed clinical assays to detect human exposures to nerve agents through the analysis of specific protein adducts and metabolites, for which a simple extraction from a dried blood spot is sufficient for removing matrix interferents and attaining sensitivities on par with traditional sampling methods. The use of dried blood spots can bridge the gap between the laboratory and the field allowing for large scale sample collection with minimal impact on hospital resources while maintaining sensitivity, specificity, traceability, and quality requirements for both clinical and forensic applications.

Evaluation of some microbial agents, natural and chemical compounds for controlling tomato leaf miner, Tuta absoluta (Meyrick (Lepidoptera: Gelechiidae

Directory of Open Access Journals (Sweden)

Abd El-Ghany Nesreen M.

2016-12-01

Full Text Available Solanaceous plants have a great economic impact in Egypt. These groups of plants include potatoes, tomatoes and eggplants. The new invasive pest of tomatoes, Tuta absoluta (Meyrick causes the greatest crop losses which can range from 60 to 100%. After its detection in Egypt during the last half of 2009, it spread quickly to all provinces in the country. We aiming to propose a sustainable control program for this devastating pest. In this research we tested three groups of control agents. The first was microbial and natural, the second - plant extracts and the third - chemical insecticides. Our results showed that the impact of T. absoluta can be greatly reduced by the use of sustainable control measures represented by different insecticide groups. Bioassay experiments showed that this devastating pest can be controlled with some compounds that give high mortality rates. Of these compounds, spinosad and Beauveria bassiana, microbial control agents, followed by azadirachtin, gave the best results in controlling T. absoluta. Of the chemical insecticides, lambda-cyhalotrin was the most effective, followed by lufenuron and profenofos. In conclusion we encourage farmers to use microbial and natural control measures in combating the tomato leafminer, T. absoluta, in Integrated Pest Mangement (IPM programs.

Chemical hybridizing agent SQ-1-induced male sterility in Triticum aestivum L.: a comparative analysis of the anther proteome.

Science.gov (United States)

Liu, Hongzhan; Zhang, Gaisheng; Wang, Junsheng; Li, Jingjing; Song, Yulong; Qiao, Lin; Niu, Na; Wang, Junwei; Ma, Shoucai; Li, Lili

2018-01-05

Heterosis is widely used to increase the yield of many crops. However, as wheat is a self-pollinating crop, hybrid breeding is not so successful in this organism. Even though male sterility induced by chemical hybridizing agents is an important aspect of crossbreeding, the mechanisms by which these agents induce male sterility in wheat is not well understood. We performed proteomic analyses using the wheat Triticum aestivum L.to identify those proteins involved in physiological male sterility (PHYMS) induced by the chemical hybridizing agent CHA SQ-1. A total of 103 differentially expressed proteins were found by 2D-PAGE and subsequently identified by MALDI-TOF/TOF MS/MS. In general, these proteins had obvious functional tendencies implicated in carbohydrate metabolism, oxidative stress and resistance, protein metabolism, photosynthesis, and cytoskeleton and cell structure. In combination with phenotypic, tissue section, and bioinformatics analyses, the identified differentially expressed proteins revealed a complex network behind the regulation of PHYMS and pollen development. Accordingly, we constructed a protein network of male sterility in wheat, drawing relationships between the 103 differentially expressed proteins and their annotated biological pathways. To further validate our proposed protein network, we determined relevant physiological values and performed real-time PCR assays. Our proteomics based approach has enabled us to identify certain tendencies in PHYMS anthers. Anomalies in carbohydrate metabolism and oxidative stress, together with premature tapetum degradation, may be the cause behind carbohydrate starvation and male sterility in CHA SQ-1 treated plants. Here, we provide important insight into the mechanisms underlying CHA SQ-1-induced male sterility. Our findings have practical implications for the application of hybrid breeding in wheat.

Persistent extra-axial post-surgical collections and Propionibacterium acnes infection. Presentation of two cases and literature review.

Science.gov (United States)

González, Pedro; Thenier, José; Galárraga, Raúl; de la Lama, Adolfo; Azevedo, Eva; Conde, Cesáreo

It is common to observe the persistence of extra-axial collections after craniotomies. Most of these disappear in weeks or months but some remain. The onset of focal symptoms or the growth of these persistent collections months or years after surgery may indicate the presence of a chronic and latent infection by germs of low virulence such as Propionibacterium acnes (P. acnes). We present two clinical cases with persistent extra-axial collections, which required surgery years after diagnosis, in which P. acnes was isolated as an aetiological agent and we reviewed the literature published in this regard. These are two patients who, following surgical procedures (decompressive craniectomy for severe TBI and craniotomy for right parietal meningioma) and extra-axial collections were kept, which were monitored over time and then were infected and required emergency evacuation. In these collections P. acnes grew as a causal agent and required targeted antibiotics. We must consider P. acnes as an infectious agent of post-surgical collections of long evolution. Atypical presentation and radiological changes may be helpful in diagnosis. Copyright © 2017 Sociedad Española de Neurocirugía. Publicado por Elsevier España, S.L.U. All rights reserved.

Chemical sensing underclothing system for testing PPE

International Nuclear Information System (INIS)

Slabotinsky, J.; Kralik, L.; Bradka, S.; Castulik, P.

2009-01-01

Personal protective equipment (PPE) when worn is subjected to pressure differentials across the garment due to ambient wind flow, by body movement and breathing creating the bellows effect, which may force hazardous chemicals vapor or aerosol through the closures, joints, outlet valves and/or clothing protective fabric. Thus the design, fit, size or improper donning of the protective garment will influence chemical-agent penetration. In order to determine penetration of chemical-protective garments by chemical vapor or aerosol, it is necessary to test the entire suit system, including seams, closures, outlet valves and areas of transition with other protective equipment, that is, at the ankles, waist, wrists, neck etc. In order to identify penetration of chemical vapor or aerosol through protective assembly, the Man-in-Simulant Test (MIST) with passive adsorptive devices (PADs) is used, when adsorbed challenging agent (simulant) is desorbed from the PAD and quantified. The current MIST method is failing in complexity of leak detection, due to limited number of passive collection points fixed on human body or a mannequin and very labor extensive work associated with allocation of 20-40 PADs and quantification of adsorbed agent. The Czech approach to detect and quantify penetration/permeation of chemical agent is based on chemical sensing underclothing enable to change the color when exposed with simulant or even with real CW agent. Color intensity and shape of stains on sensing fabric are processed with Laboratory Universal Computer Image Analysis (LUCIA) allowing determining the quantity and the allocation of the penetrating noxious agent(s). This method allows for example calculate individual doses of exposure, the breakthrough coefficient of protective garment as whole and uniquely precise allocation of penetration/permeation shortfalls. Presentation is providing detailed description of imaging system with nickname 'LUCY' in combination with testing mannequin

Atmospheric transport of persistent semi-volatile organic chemicals to the Arctic and cold condensation in the mid-troposphere – Part 1: 2-D modeling in mean atmosphere

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J. Ma

2010-08-01

Full Text Available In the first part of this study for revisiting the cold condensation effect on global distribution of semi-volatile organic chemicals (SVOCs, the atmospheric transport of SVOCs to the Arctic in the mid-troposphere in a mean meridional atmospheric circulation over the Northern Hemisphere was simulated by a two-dimensional (2-D atmospheric transport model. Results show that under the mean meridional atmospheric circulation the long-range atmospheric transport of SVOCs from warm latitudes to the Arctic occurs primarily in the mid-troposphere. Although major sources are in low and mid-latitude soils, the modeled air concentration of SVOCs in the mid-troposphere is of the same order as or higher than that near the surface, demonstrating that the mid-troposphere is an important pathway and reservoir of SVOCs. The cold condensation of the chemicals is also likely to take place in the mid-troposphere over a source region of SVOCs in warm low latitudes through interacting with clouds. We demonstrate that the temperature dependent vapour pressure and atmospheric degradation rate of SVOCs exhibit similarities between lower atmosphere over the Arctic and the mid-troposphere over a tropical region. Frequent occurrence of atmospheric ascending motion and convection over warm latitudes carry the chemicals to a higher altitude where some of these chemicals may partition onto solid or aqueous phase through interaction with atmospheric aerosols, cloud water droplets and ice particles, and become more persistent at lower temperatures. Stronger winds in the mid-troposphere then convey solid and aqueous phase chemicals to the Arctic where they sink by large-scale descending motion and wet deposition. Using calculated water droplet-air partitioning coefficient of several persistent organic semi-volatile chemicals under a mean air temperature profile from the equator to the North Pole we propose that clouds are likely important sorbing media for SVOCs and pathway of

Report on NCI symposium: comparison of mechanisms of carcinogenesis by radiation and chemical agents. II. Cellular and animal models

International Nuclear Information System (INIS)

Fry, R.J.M.

1984-01-01

The point at which the common final pathway for induction of cancer by chemical carcinogens and ionizing radiation has not been identified. Although common molecular targets are suggested by recent findings about the role of oncogenes, the mechanism by which the deposition of radiation energy and the formation of adducts or other DNA lesions induced by chemicals affects the changes in the relevant targets may be quite different. The damage to DNA that plays no part in the transformation events, but that influences the stability of the genome, and therefore, the probability of subsequent changes that influence tumorigenesis may be more readily induced by some agents than others. Similarly, the degree of cytotoxic effects that disrupt tissue integrity and increase the probability of expression of initiated cells may be dependent on the type of carcinogen. Also, evidence was presented that repair of the initial lesions could be demonstrated after exposure to low-LET radiation but not after exposure to chemical carcinogens

Report on NCI symposium: comparison of mechanisms of carcinogenesis by radiation and chemical agents. II. Cellular and animal models

Energy Technology Data Exchange (ETDEWEB)

Fry, R.J.M.

1984-01-01

The point at which the common final pathway for induction of cancer by chemical carcinogens and ionizing radiation has not been identified. Although common molecular targets are suggested by recent findings about the role of oncogenes, the mechanism by which the deposition of radiation energy and the formation of adducts or other DNA lesions induced by chemicals affects the changes in the relevant targets may be quite different. The damage to DNA that plays no part in the transformation events, but that influences the stability of the genome, and therefore, the probability of subsequent changes that influence tumorigenesis may be more readily induced by some agents than others. Similarly, the degree of cytotoxic effects that disrupt tissue integrity and increase the probability of expression of initiated cells may be dependent on the type of carcinogen. Also, evidence was presented that repair of the initial lesions could be demonstrated after exposure to low-LET radiation but not after exposure to chemical carcinogens.

Wearable Atmospheric Pressure Plasma Fabrics Produced by Knitting Flexible Wire Electrodes for the Decontamination of Chemical Warfare Agents

Science.gov (United States)

Jung, Heesoo; Seo, Jin Ah; Choi, Seungki

2017-01-01

One of the key reasons for the limited use of atmospheric pressure plasma (APP) is its inability to treat non-flat, three-dimensional (3D) surface structures, such as electronic devices and the human body, because of the rigid electrode structure required. In this study, a new APP system design—wearable APP (WAPP)—that utilizes a knitting technique to assemble flexible co-axial wire electrodes into a large-area plasma fabric is presented. The WAPP device operates in ambient air with a fully enclosed power electrode and grounded outer electrode. The plasma fabric is flexible and lightweight, and it can be scaled up for larger areas, making it attractive for wearable APP applications. Here, we report the various plasma properties of the WAPP device and successful test results showing the decontamination of toxic chemical warfare agents, namely, mustard (HD), soman (GD), and nerve (VX) agents.

Benzotriazole as a passivating agent during chemical mechanical planarization of Ni–P alloy substrates

International Nuclear Information System (INIS)

Mu, Yan; Zhong, Mingjie; Rushing, Kenneth J.; Li, Yuzhuo; Shipp, Devon A.

2014-01-01

Highlights: • Benzotriazole (BTA) is used to passivate the Chemical Mechanical Planarization of Ni-P alloys. • BTA significantly decreases the average R a of the polished surfaces at low concentrations. • XPS, AFM and electrochemical studies are used to probe passivation effects of BTA on Ni–P surfaces. • Findings potentially impact hard disk drive manufacturing processes. - Abstract: With the rapid increase of data storage density on computer hard disk drives (HDDs), the operation distance between read/write head and disk surface has fallen to just a few nanometers. Chemical mechanical planarization (CMP) has been selected as the best process to produce high quality surface finish during the manufacturing of Ni–P alloy substrates for HDD applications. Herein we report, for the first time, the use of benzotriazole (BTA) as a passivating agent in CMP slurries to decrease the surface roughness (R a ). Results show that the average R a of the polished surfaces is decreased to 0.2 nm in a 5 μm × 5 μm scan area with the adding of 2 mM BTA. X-ray photoelectron spectroscopy (XPS) and electrochemical studies results further prove the interaction between BTA and Ni–P surface and the formation of an effective passivating layer on Cu in CMP slurries containing BTA

Chiral separation of G-type chemical warfare nerve agents via analytical supercritical fluid chromatography.

Science.gov (United States)

Kasten, Shane A; Zulli, Steven; Jones, Jonathan L; Dephillipo, Thomas; Cerasoli, Douglas M

2014-12-01

Chemical warfare nerve agents (CWNAs) are extremely toxic organophosphorus compounds that contain a chiral phosphorus center. Undirected synthesis of G-type CWNAs produces stereoisomers of tabun, sarin, soman, and cyclosarin (GA, GB, GD, and GF, respectively). Analytical-scale methods were developed using a supercritical fluid chromatography (SFC) system in tandem with a mass spectrometer for the separation, quantitation, and isolation of individual stereoisomers of GA, GB, GD, and GF. Screening various chiral stationary phases (CSPs) for the capacity to provide full baseline separation of the CWNAs revealed that a Regis WhelkO1 (SS) column was capable of separating the enantiomers of GA, GB, and GF, with elution of the P(+) enantiomer preceding elution of the corresponding P(-) enantiomer; two WhelkO1 (SS) columns had to be connected in series to achieve complete baseline resolution. The four diastereomers of GD were also resolved using two tandem WhelkO1 (SS) columns, with complete baseline separation of the two P(+) epimers. A single WhelkO1 (RR) column with inverse stereochemistry resulted in baseline separation of the GD P(-) epimers. The analytical methods described can be scaled to allow isolation of individual stereoisomers to assist in screening and development of countermeasures to organophosphorus nerve agents. © 2014 The Authors. Chirality published by John Wiley Periodicals, Inc.

Decontamination of Chemical/Biological Warfare (CBW) Agents Using an Atmospheric Pressure Plasma Jet (APPJ)

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Herrmann, Hans W.

1998-11-01

The atmospheric pressure plasma jet (APPJ) is a non-thermal, high pressure, uniform glow discharge that produces a high velocity effluent stream of highly reactive chemical species. The discharge operates on a feedstock gas (e.g. He/O_2/H_2O) which flows between an outer, grounded, cylindrical electrode and an inner, coaxial electrode powered at 13.56 MHz RF. While passing through the plasma, the feedgas becomes excited, dissociated or ionized by electron impact. Once the gas exits the discharge volume, ions and electrons are rapidly lost by recombination, but the fast-flowing effluent still contains metastables (e.g. O2*, He*) and radicals (e.g. O, OH). These reactive species have been shown to be effective neutralizers of surrogates for anthrax spores, mustard blister agent and VX nerve gas. Unlike conventional, wet decontamination methods, the plasma effluent does not cause corrosion of most surfaces and does not damage wiring, electronics, nor most plastics. This makes it highly suitable for decontamination of high value sensitive equipment such as is found in vehicle interiors (i.e. tanks, planes...) for which there is currently no good decontamination technique. Furthermore, the reactive species rapidly degrade into harmless products leaving no lingering residue or harmful byproducts. Physics of the APPJ will be discussed and results of surface decontamination experiments using simulant and actual CBW agents will be presented.

Evaluation of Veriox as a Skin Decontamination Product after Dermal Exposure to the Nerve Agent VX

Science.gov (United States)

2016-09-01

was to determine whether Veriox® had efficacy as a decontamination product (DC) after skin exposure to the chemical warfare agent VX. This study...countermeasure, decontamination , RSDL, VX, nerve agent, cutaneous exposure, chemical warfare agent 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT...invested considerable resources in developing detectors, protective garments, and products to remove and/or decontaminate chemical agent exposure on

Alkalisation agent measurement with differential conductivity method in secondary water system

International Nuclear Information System (INIS)

Wuhrmann, Peter; Lendi, Marco

2012-09-01

Besides ammonia hydroxide, also morpholine and ethanol-amine (ETA) are mainly used as a pH regulating agent on the secondary water side [1]. The concentration of the alkalisation agent can only be calculated if the chemical composition in the sample is known [2]. Therefore, for a reliable alkalisation agent measurement, there are three major steps to take: A reliable specific and (degassed) acid conductivity measurement, pH calculation and the selection of the chemical model for concentration calculation of the alkalisation agent (authors)

Persistence of Mycoplasma genitalium following azithromycin therapy.

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Catriona S Bradshaw

Full Text Available BACKGROUND: To determine clinical outcomes and cure rates for M.genitalium genital infection in men and women following azithromycin 1 g. METHODOLOGY: Patients attending Melbourne Sexual Health Centre between March 2005 and November 2007 with urethritis/epididymitis, cervicitis/pelvic inflammatory disease and sexual contacts of M.genitalium were tested for M.genitalium by polymerase chain reaction (PCR. M.genitalium-infection was treated with 1 g of azithromycin and a test-of-cure (toc was performed one month post-azithromycin. Response to azithromycin, and response to moxifloxacin (400 mg daily for 10 days in individuals with persistent infection post-azithromycin, was determined. PRINCIPAL FINDINGS: Of 1538 males and 313 females tested, 161 males (11% and 30 females (10% were infected with M.genitalium. A toc was available on 131 (69% infected individuals (median = 36 days [range 12-373]. Of 120 individuals prescribed azithromycin only pre-toc, M.genitalium was eradicated in 101 (84%, 95% confidence intervals [CI]: 77-90% and persisted in 19 (16%, 95% CI: 10-23%. Eleven individuals with persistent infection (9%, 95% CI: 5-15% had no risk of reinfection from untreated-partners, while eight (7%, 95% CI: 3-12% may have been at risk of reinfection from doxycycline-treated or untreated-partners. Moxifloxacin was effective in eradicating persistent infection in all cases not responding to azithromycin. Patients with persistent-M.genitalium were more likely to experience persistent symptoms (91%, compared to patients in whom M.genitalium was eradicated (17%, p<0.0001. CONCLUSION: Use of azithromycin 1 g in M.genitalium-infected patients was associated with unacceptable rates of persistent infection, which was eradicated with moxifloxacin. These findings highlight the importance of follow-up in M.genitalium-infected patients prescribed azithromycin, and the need to monitor for the development of resistance. Research to determine optimal first and

Low Level Chemical Toxicity: Relevance to Chemical Agent Defense

Science.gov (United States)

2005-07-01

or confirm a diagnosis of chemical sensitivity and suggest novel approaches in managing this malady. Project 4: Studies of gene expression...Lindberg I, Ugleholdt R, Holst J & Steiner DF 2002b Disruption of PC1/3 expression in mice causes dwarfism and multiple neuroendocrine peptide processing...2004;1:32- 34. [10] Diederich S,Eckmanns,T,Exner,P,Al-Saadi,N,Bahr,V,Oelkers,W. Differential diagnosis of polyuric/polydipsic syndromes with the aid

A New Generation of Thermal Desorption Technology Incorporating Multi Mode Sampling (NRT/DAAMS/Liquid Agent) for Both on and off Line Analysis of Trace Level Airbone Chemical Warfare Agents

International Nuclear Information System (INIS)

Roberts, G. M.

2007-01-01

A multi functional, twin-trap, electrically-cooled thermal desorption (TD) system (TT24-7) will be discussed for the analysis of airborne trace level chemical warfare agents. This technology can operate in both military environments (CW stockpile, or destruction facilities) and civilian locations where it is used to monitor for accidental or terrorist release of acutely toxic substances. The TD system interfaces to GC, GCMS or direct MS analytical platforms and provides for on-line continuous air monitoring with no sampling time blind spots and within a near real time (NRT) context. Using this technology enables on-line sub ppt levels of agent detection from a vapour sample. In addition to continuous sampling the system has the capacity for off-line single (DAAMS) tube analysis and the ability to receive an external liquid agent injection. The multi mode sampling functionality provides considerable flexibility to the TD system, allowing continuous monitoring of an environment for toxic substances plus the ability to analyse calibration standards. A calibration solution can be introduced via a conventional sampling tube on to either cold trap or as a direct liquid injection using a conventional capillary split/splitless injection port within a gas chromatograph. Low level (linearity) data will be supplied showing the TT24-7 analyzing a variety of CW compounds including free (underivitised) VX using the three sampling modes described above. Stepwise changes in vapor generated agent concentrations will be shown, and this is cross referenced against direct liquid agent introduction, and the tube sampling modes. This technology is in use today in several geographies around the world in both static and mobile analytical laboratories. (author)

Alarms, Chemical

Science.gov (United States)

cited in applicable qualitative materiel requirements, small development requirements, technical characteristics, and other requirements and documentation that pertain to automatic chemical agent alarms.

Investigations of chemical warfare agents and toxic industrial compounds with proton-transfer-reaction mass spectrometry for a real-time threat monitoring scenario.

Science.gov (United States)

Kassebacher, Thomas; Sulzer, Philipp; Jürschik, Simone; Hartungen, Eugen; Jordan, Alfons; Edtbauer, Achim; Feil, Stefan; Hanel, Gernot; Jaksch, Stefan; Märk, Lukas; Mayhew, Chris A; Märk, Tilmann D

2013-01-30

Security and protection against terrorist attacks are major issues in modern society. One especially challenging task is the monitoring and protection of air conditioning and heating systems of buildings against terrorist attacks with toxic chemicals. As existing technologies have low selectivity, long response times or insufficient sensitivity, there is a need for a novel approach such as we present here. We have analyzed various chemical warfare agents (CWAs) and/or toxic industrial compounds (TICs) and related compounds, namely phosgene, diphosgene, chloroacetone, chloroacetophenone, diisopropylaminoethanol, and triethyl phosphate, utilizing a high-resolution proton-transfer-reaction time-of-flight mass spectrometry (PTR-TOFMS) instrument with the objective of finding key product ions and their intensities, which will allow a low-resolution quadrupole mass spectrometry based PTR-MS system to be used with high confidence in the assignment of threat agents in the atmosphere. We obtained high accuracy PTR-TOFMS mass spectra of the six compounds under study at two different values for the reduced electric field in the drift tube (E/N). From these data we have compiled a table containing product ions, and isotopic and E/N ratios for highly selective threat compound detection with a compact and cost-effective quadrupole-based PTR-MS instrument. Furthermore, using chloroacetophenone (tear gas), we demonstrated that this instrument's response is highly linear in the concentration range of typical Acute Exposure Guideline Levels (AEGLs). On the basis of the presented results it is possible to develop a compact and cost-effective PTR-QMS instrument that monitors air supply systems and triggers an alarm as soon as the presence of a threat agent is detected. We hope that this real-time surveillance device will help to seriously improve safety and security in environments vulnerable to terrorist attacks with toxic chemicals. Copyright © 2012 John Wiley & Sons, Ltd.

Long-Term Persistence of Pseudogymnoascus destructans, the Causative Agent of White-Nose Syndrome, in the Absence of Bats.

Science.gov (United States)

Hoyt, Joseph R; Langwig, Kate E; Okoniewski, Joseph; Frick, Winifred F; Stone, Ward B; Kilpatrick, A Marm

2015-06-01

Wildlife diseases have been implicated in the declines and extinctions of several species. The ability of a pathogen to persist outside its host, existing as an "environmental reservoir", can exacerbate the impact of a disease and increase the likelihood of host extinction. Pseudogymnoascus destructans, the fungal pathogen that causes white-nose syndrome in bats, has been found in cave soil during the summer when hibernating bats had likely been absent for several months. However, whether the pathogen can persist over multiple years in the absence of bats is unknown, and long-term persistence of the pathogen can influence whether hibernacula where bats have been locally extirpated due to disease can be subsequently recolonized. Here, we show that P. destructans is capable of long-term persistence in the laboratory in the absence of bats. We cultured P. destructans from dried agar plates that had been kept at 5°C and low humidity conditions (30-40% RH) for more than 5 years. This suggests that P. destructans can persist in the absence of bats for long periods which may prevent the recolonization of hibernation, sites where bat populations were extirpated. This increases the extinction risk of bats affected by this disease.

Biological effects of radiation and chemical agents with special regard to repair processes

International Nuclear Information System (INIS)

Altmann, H.; Wottawa, A.

1980-01-01

It is reasonably certain that the introduction or increase of pollutants in the environment can augment mutagenic and carcinogenic effects. These effects are operationally definable, but the genetic organization and the underlying mechanisms of DNA repair, mutagenesis and carcinogenesis are so complex as to make the extrapolation of results from mutagenicity test data to carcinogenicity somewhat uncertain. The subject is reviewed. Recent discoveries in gene organization and expression include overlapping genes in bacteriophages, split genes, processing of RNA and splicing, translocation of genes in eukaryotes, inactivation of the X-chromosome in mammals, etc. Apart from the genetic regulation, plasmids, insertion sequences and mutators can additionally affect mutation frequency. Cancers due to gene mutations, viruses, chemicals and physical agents are known. However, little is known about the epigenetic mechanisms involved. The value of mutagenicity test data is beyond question, but in view of the extraordinary complexities encountered our extrapolations will be more sound if the data have the underpinning of basic information. (author)

Comparison of the lethal effects of chemical warfare nerve agents across multiple ages.

Science.gov (United States)

Wright, Linnzi K M; Lee, Robyn B; Vincelli, Nicole M; Whalley, Christopher E; Lumley, Lucille A

2016-01-22

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 24h 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. Published by Elsevier Ireland Ltd.

Stress cracking e ataque químico do PET em diferentes agentes químicos Stress cracking and chemical attack of pet under different chemicals

Directory of Open Access Journals (Sweden)

Edvânia T. Teófilo

2009-01-01

Full Text Available A análise de resistência ao stress cracking (ESCR do PET foi feita em corpos de prova de tração moldados por injeção, utilizando vários agentes químicos (metanol, etanol, propanol, butanol e soluções de hidróxido de sódio em diferentes concentrações. Foram realizados ensaios dinâmicos e estáticos de tração. Durante os testes os corpos de prova foram mantidos em contato com os agentes e as propriedades mecânicas monitoradas. Os resultados evidenciam que todas as soluções de hidróxidos de sódio testadas são agentes agressivos de ESC por diminuírem as propriedades mecânicas do polímero, ocasionando falha catastrófica. Já os demais fluidos, apesar de não terem efeito significativo nas propriedades do PET, afetam drasticamente sua aparência superficial. Observou-se também a ocorrência de ataque químico nos ensaios com NaOH, resultando em redução nas massas molares.The investigation of stress cracking resistance (ESCR of PET was done in injection-moulded tensile test bars using different fluids as active agents. These were methanol, ethanol, propanol, butanol and solutions based on sodium hydroxide. Both dynamic and static tensile experiments were conducted. During the tensile experiments, the samples were kept in contact with the fluids and the mechanical properties were monitored. The results showed that all sodium hydroxide solutions were aggressive stress cracking agents for PET, reducing mechanical properties and causing catastrophic failure. On the other hand, the other fluids did not cause much influence on the mechanical behaviour but changed drastically the surface appearance. Also observed was a chemical attack when NaOH solutions were used, causing a reduction in molar mass of PET molecules.

Pursuit of communal values in an agentic manner: a way to happiness?

Science.gov (United States)

Abele, Andrea E.

2014-01-01

The present research studies the association between traits, values, and life satisfaction. While values should influence the direction of an individual’s goals and behavior, his/her traits impact effort-expenditure, efficiency, and persistence in goal-pursuit. We apply the framework of the “Big Two” of agency and communion (Bakan, 1966) for distinguishing the content of values and traits. While agentic content refers to qualities relevant for goal-attainment, such as assertiveness, competence or persistence, communal content refers to qualities relevant for the establishment and maintenance of social relationships, such as being friendly, helpful, or fair. We predict that high scores on communal values and high scores on agentic traits are associated with life satisfaction. We test these predictions in two studies conducted in different countries (Germany and Russia) with different cultural background. The findings support our reasoning: across both countries we find positive associations of communal values and agentic traits with life satisfaction; and individuals high in communal values and high in agentic traits are most satisfied with their lives. In Russia, the association of communal values with life satisfaction is moderated by agentic traits; in Germany, however, there is a main effect of communal values. PMID:25477843

Pursuit of communal values in an agentic manner: A way to happiness?

Directory of Open Access Journals (Sweden)

Andrea Elisabeth Abele

2014-11-01

Full Text Available The present research studies the association between traits, values and life satisfaction. While values should influence the direction of an individual’s goals and behaviour, his/her traits impact effort expenditure, efficiency and persistence in goal-pursuit. We apply the framework of the Big Two of agency and communion (Bakan, 1966 for distinguishing the content of values and traits. While agentic content refers to qualities relevant for goal-attainment, such as assertiveness, competence or persistence, communal content refers to qualities relevant for the establishment and maintenance of social relationships, such as being friendly, helpful, or fair. We predict that high scores on communal values and high scores on agentic traits are associated with life satisfaction. We test these predictions in two studies conducted in different countries (Germany and Russia with different cultural background. The findings support our reasoning: Across both countries we find positive associations of communal values and agentic traits with life satisfaction; and individuals high in communal values and high in agentic traits are most satisfied with their lives. In Russia, the association of communal values with life satisfaction is moderated by agentic traits; in Germany, however, there is a main effect of communal values.

Analysis of chemical warfare agents in food products by atmospheric pressure ionization-high field asymmetric waveform ion mobility spectrometry-mass spectrometry.

Science.gov (United States)

Kolakowski, Beata M; D'Agostino, Paul A; Chenier, Claude; Mester, Zoltán

2007-11-01

Flow injection high field asymmetric waveform ion mobility spectrometry (FAIMS)-mass spectrometry (MS) methodology was developed for the detection and identification of chemical warfare (CW) agents in spiked food products. The CW agents, soman (GD), sarin (GB), tabun (GA), cyclohexyl sarin (GF), and four hydrolysis products, ethylphosphonic acid (EPA), methylphosphonic acid (MPA), pinacolyl methylphosphonic acid (Pin MPA), and isopropyl methylphosphonic acid (IMPA) were separated and detected by positive ion and negative ion atmospheric pressure ionization-FAIMS-MS. Under optimized conditions, the compensation voltages were 7.2 V for GD, 8.0 V for GA, 7.2 V for GF, 7.6 V for GB, 18.2 V for EPA, 25.9 V for MPA, -1.9 V for PinMPA, and +6.8 V for IMPA. Sample preparation was kept to a minimum, resulting in analysis times of 3 min or less per sample. The developed methodology was evaluated by spiking bottled water, canola oil, cornmeal, and honey samples at low microgram per gram (or microg/mL) levels with the CW agents or CW agent hydrolysis products. The detection limits observed for the CW agents in the spiked food samples ranged from 3 to 15 ng/mL in bottled water, 1-33 ng/mL in canola oil, 1-34 ng/g in cornmeal, and 13-18 ng/g in honey. Detection limits were much higher for the CW agent hydrolysis products, with only MPA being detected in spiked honey samples.

Chemical, Biological, Radiological, Nuclear, and High-Yield Explosives Consequences Management

Science.gov (United States)

2006-10-02

protective measures associated with such offensive operations. Since riot control agents and herbicides are not considered to be chemical warfare agents...control. Procedures to avoid, reduce, remove, or render harmless (temporarily or permanently) nuclear, radiological, biological, and chemical...destroying, neutralizing, making harmless , or removing chemical or biological agents, or by removing radioactive material clinging to or around it. (JP 1

Adsorption and Desorption of Chemical Warfare Agent Simulants on Silica Surfaces with Hydrophobic Coating

International Nuclear Information System (INIS)

Park, Eun Ji; Kim, Young Dok

2013-01-01

Aim of our study is finding adsorbents suitable for pre-concentration of chemical warfare agents (CWAs). We considered Tenax, bare silica and polydimethylsiloxane (PDMS)-coated silica as adsorbents for dimethyl methylphosphonate (DMMP) and dipropylene glycol methyl ether (DPGME). Tenax showed lower thermal stability, and therefore, desorption of CWA simulants and decomposition of Tenax took place simultaneously. Silica-based adsorbents showed higher thermal stabilities than Tenax. A drawback of silica was that adsorption of CWA simulant (DMMP) was significantly reduced by pre-treatment of the adsorbents with humid air. In the case of PDMS-coated silica, influence of humidity for CWA simulant adsorption was less pronounced due to the hydrophobic nature of PDMS-coating. We propose that PDMS-coated silica can be of potential importance as adsorbent of CWAs for their pre-concentration, which can facilitate detection of these CWAs

Adsorption and Desorption of Chemical Warfare Agent Simulants on Silica Surfaces with Hydrophobic Coating

Energy Technology Data Exchange (ETDEWEB)

Park, Eun Ji; Kim, Young Dok [Sungkyunkwan Univ., Suwon (Korea, Republic of)

2013-07-15

Aim of our study is finding adsorbents suitable for pre-concentration of chemical warfare agents (CWAs). We considered Tenax, bare silica and polydimethylsiloxane (PDMS)-coated silica as adsorbents for dimethyl methylphosphonate (DMMP) and dipropylene glycol methyl ether (DPGME). Tenax showed lower thermal stability, and therefore, desorption of CWA simulants and decomposition of Tenax took place simultaneously. Silica-based adsorbents showed higher thermal stabilities than Tenax. A drawback of silica was that adsorption of CWA simulant (DMMP) was significantly reduced by pre-treatment of the adsorbents with humid air. In the case of PDMS-coated silica, influence of humidity for CWA simulant adsorption was less pronounced due to the hydrophobic nature of PDMS-coating. We propose that PDMS-coated silica can be of potential importance as adsorbent of CWAs for their pre-concentration, which can facilitate detection of these CWAs.

Induction of stress responses by polluting agents which dis-regulate cellular homeostasis

International Nuclear Information System (INIS)

Mothersill, Carmel

2001-01-01

There is growing concern both in the scientific community and among the general public about the effects of exposure to low levels of radiation and environmental chemicals. The increased incidence of cancer, reproduction disorders and allergies have been associated with ambient environmental exposure to these pollutants. The pollution burden is generally made up of a mixture of agents, occurring at concentrations of the individual compounds which are not considered harmful and which are below the action level. Individual pollutants can act through a variety of primary toxicity mechanisms. However the resulting secondary and tertiary toxicity mechanisms which affect cellular homeostasis might be more common. These resulting stress responses, including oxidative stress, have been associated with effects that include increased level of death during cell division, increased levels of mutation and increased tolerance of mutations in cell populations, increased levels of cytogenetic abnormalities and many other symptoms. These effects are linked to a persistent increase in (oxidative) stress and are particularly evident in the haematopoietic system (possibly due to the high rate self of renewal in that system). Therefore prolonged exposure to mixtures of chemicals and radiation might result in additive and synergistic stress responses which can induce long-term delayed effects, often in progeny or in cells not directly exposed to the agent/s. The existence of a common (oxidative) stress mechanism means that the effects of individual pollutants may not be considered in isolation. Rather the total pollution burden may need to be measured using a response rather than a dose based scoring or ranking system. Improved understanding of toxicity mechanisms and effects underpins improved risk assessment and identification of biomarkers. The immune system plays a pivotal role in maintaining health status, and disruption of immune functions can lead to increased susceptibility to

A Polyoxoniobate-Polyoxovanadate Double-Anion Catalyst for Simultaneous Oxidative and Hydrolytic Decontamination of Chemical Warfare Agent Simulants.

Science.gov (United States)

Dong, Jing; Hu, Jufang; Chi, Yingnan; Lin, Zhengguo; Zou, Bo; Yang, Song; Hill, Craig L; Hu, Changwen

2017-04-10

A novel double-anion complex, H 13 [(CH 3 ) 4 N] 12 [PNb 12 O 40 (V V O) 2 ⋅(V IV 4 O 12 ) 2 ]⋅22 H 2 O (1), based on bicapped polyoxoniobate and tetranuclear polyoxovanadate was synthesized, characterized by routine techniques and used in the catalytic decontamination of chemical warfare agents. Under mild conditions, 1 catalyzes both hydrolysis of the nerve agent simulant, diethyl cyanophosphonate (DECP) and selective oxidation of the sulfur mustard simulant, 2-chloroethyl ethyl sulfide (CEES). In the oxidative decontamination system 100 % CEES was transformed selectively to nontoxic 2-chloroethyl ethyl sulfoxide and vinyl ethyl sulfoxide using nearly stoichiometric 3 % aqueous H 2 O 2 with a turnover frequency (TOF) of 16 000 h -1 . Importantly, the catalytic activity is maintained even after ten recycles and CEES is completely decontaminated in 3 mins without formation of the highly toxic sulfone by-product. A three-step oxidative mechanism is proposed. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Continuum Model for Decontamination of Chemical Warfare Agent from a Rubbery Polymer using the Maxwell-Stefan Formulation

Science.gov (United States)

Varady, Mark; Bringuier, Stefan; Pearl, Thomas; Stevenson, Shawn; Mantooth, Brent

Decontamination of polymers exposed to chemical warfare agents (CWA) often proceeds by application of a liquid solution. Absorption of some decontaminant components proceed concurrently with extraction of the CWA, resulting in multicomponent diffusion in the polymer. In this work, the Maxwell-Stefan equations were used with the Flory-Huggins model of species activity to mathematically describe the transport of two species within a polymer. This model was used to predict the extraction of the nerve agent O-ethyl S-[2(diisopropylamino)ethyl] methylphosphonothioate (VX) from a silicone elastomer into both water and methanol. Comparisons with experimental results show good agreement with minimal fitting of model parameters from pure component uptake data. Reaction of the extracted VX with sodium hydroxide in the liquid-phase was also modeled and used to predict the overall rate of destruction of VX. Although the reaction proceeds more slowly in the methanol-based solution compared to the aqueous solution, the extraction rate is faster due to increasing VX mobility as methanol absorbs into the silicone, resulting in an overall faster rate of VX destruction.

Milling overrides cultivar, leavening agent and baking mode on chemical and rheological traits and sensory perception of durum wheat breads.

Science.gov (United States)

Ficco, Donatella Bianca Maria; Saia, Sergio; Beleggia, Romina; Fragasso, Mariagiovanna; Giovanniello, Valentina; De Vita, Pasquale

2017-10-19

Smell and aroma are important determinants of consumer acceptance, so gaining deeper insight into bread smell and aroma perception is a research goal. Sixteen combinations of four variables were investigated, to evaluate the contributions of bread chemical and rheological properties and volatile organic compounds (VOCs) towards sensory acceptability of breads: genotypes (landrace vs. modern); types of flour (wholemeal vs. semolina); leavening agents (brewing yeast vs. sourdough starter); and baking modes (gas-fired vs. wood-fired). Milling had the greatest impact over the other treatments for the rheological and chemical properties, including for VOCs, with great impact on the sensory traits of the flours and breads. The processing phases had great impact on smell and aroma, as defined through formation of alcohols, aldehydes, terpenes, and other compounds (e.g., ethylbenzene, 2-pentylfuran, methoxyphenyl oxime). Leavening agent had great impact on sensory perception, although breads from the sourdough starter were perceived as with lower taste and colour than the brewing yeast. Baking mode had no relevant role on sensory perception. These data strongly undermine the belief of a 'better product' that is frequently attributed to old genotypes versus modern cultivars, and indicate that the milling and the bread-making processes determine the quality of the end product.

Predicting the characteristics of the aetiological agent for Kawasaki disease from other paediatric infectious diseases in Japan.

Science.gov (United States)

Nagao, Y; Urabe, C; Nakamura, H; Hatano, N

2016-02-01

Although Kawasaki disease (KD), which was first reported in the 1960s, is assumed to be infectious, its aetiological agent(s) remains unknown. We compared the geographical distribution of the force of infection and the super-annual periodicity of KD and seven other paediatric infectious diseases in Japan. The geographical distribution of the force of infection, which was estimated as the inverse of the mean patient age, was similar in KD and other paediatric viral infections. This similarity was due to the fact that the force of infection was determined largely by the total fertility rate. This finding suggests that KD shares a transmission route, i.e. sibling-to-sibling infection, with other paediatric infections. The super-annual periodicity, which is positively associated with the sum of an infectious disease's incubation period and infectious period, was much longer for KD and exanthema subitum than other paediatric infectious diseases. The virus for exanthema subitum is known to persist across the host's lifespan, which suggests that the aetiological agent for KD may also be capable of persistent infection. Taken together, these findings suggest that the aetiological agent for KD is transmitted through close contact and persists asymptomatically in most hosts.

Mesoporous persistent nanophosphors for in vivo optical bioimaging and drug-delivery

Science.gov (United States)

Maldiney, Thomas; Ballet, Benoit; Bessodes, Michel; Scherman, Daniel; Richard, Cyrille

2014-10-01

Based upon the ambitious idea that one single particle could serve multiple purposes at the same time, the combination and simultaneous use of imaging and therapeutics has lately arisen as one of the most promising prospects among nanotechnologies directed toward biomedical applications. Intended for both therapeutics and diagnostics in vivo, highly complex nanostructures were specifically designed to simultaneously act as optical imaging probes and delivery vehicles. Yet, such multifunctional photonic nanoplatforms usually exploit fluorescence phenomena which require constant excitation light through biological tissues and thus significantly reduce the detection sensitivity due to the autofluorescence from living animals. In order to overcome this critical issue, the present article introduces a novel multifunctional agent based on persistent luminescence mesoporous nanoparticles. Being composed of a hybrid chromium-doped zinc gallate core/mesoporous silica shell architecture, we show that this nanotechnology can be used as an efficient doxorubicin-delivery vehicle presenting a higher cytotoxicity toward U87MG cells than its unloaded counterpart in vitro. In addition, we demonstrate that a persistent luminescence signal from these doxorubicin-loaded mesoporous nanophosphors opens a new way to highly sensitive detection in vivo, giving access to the real-time biodistribution of the carrier without any autofluorescence from the animal tissues. This new persistent luminescence-based hybrid nanotechnology can be easily applied to the delivery of any therapeutic agent, thus constituting a versatile and sensitive optical nanotool dedicated to both therapeutic and diagnostic applications in vivo.Based upon the ambitious idea that one single particle could serve multiple purposes at the same time, the combination and simultaneous use of imaging and therapeutics has lately arisen as one of the most promising prospects among nanotechnologies directed toward biomedical

Building surface decontamination for chemical counter-terrorism

Energy Technology Data Exchange (ETDEWEB)

Harrison, S.; Thouin, G.; Kuang, W. [SAIC Canada, Ottawa, ON (Canada); Volchek, K.; Fingas, M.; Li, K. [Environment Canada, Ottawa, ON (Canada). Emergencies Science and Technology Division, Environmental Technology Centre, Science and Technology Branch

2006-07-01

A test method to compare and evaluate surface decontamination methods for buildings affected by chemical attacks was developed. Decontamination techniques generally depend on the nature and quantity of the weapon agent, the type of construction material and the location. Cleanup methods can be either physical, chemical or biological. This paper addressed chemical decontamination methods which use reactants to change the molecular structure of the contaminant. Peroxycarboxylic and peroxyacetic acids (PAA) are being used increasingly for both disinfection and environmental protection. In this study, 4 materials were chosen to represent common building materials. Samples were spiked with 10 mg of pesticides such as malathion and diazinon. Decontamination agents included the commercial decontamination agent CASCAD prepared in liquid form, a chemical preparation of PAA, and reagent grade peroxypropionic acid (PPA). The newly developed surface decontamination procedure can evaluate and compare the effectiveness of different chemical decontamination agents. The procedures were used on porous ceiling tile and carpet as well as on non-porous floor tile and painted steel surfaces. Rinse water was collected and analyzed in order to determine if decontamination was a result of chemical destruction or mechanical removal. The extraction efficiencies were found to be acceptable for all materials, with the exception of the highly porous ceiling tile. The extraction of diazinon from all surfaces was less efficient than the extraction of malathion. Results suggest that the performance of decontamination agents can be improved by repeated application of the decontamination agent, along with greater volumes and a combination of chemical and mechanical actions. It was also suggested that breakdown methods and wastewater treatment procedures should be developed because hazardous byproducts were detected in many samples. 18 refs., 1 tab., 17 figs.

Production of Antimicrobial Agent by Streptomyces violachromogenes

International Nuclear Information System (INIS)

Ahmed, Arwa A.

2007-01-01

The isolation of antibiotics from microorganisms improved the discovery of novel antibiotics, which is relatively easy as compared to chemical synthesis of antimicrobial agents. This study starts from isolation and purification of the antimicrobial producing Sterptomycetes obtained from soil habitat of Yemen. The good antimicrobial producing Sterptomycetes isolate was selected from a batch of Sterptomycetes isolates then identified. This isolate has bioactivity against some G+ve and G-ve bacteria. The antimicrobial agent isolated from Streptomyces violachromogenes (isolate no.YA118) was extracted with ethyl acetate at pH 3. The residue was applied to a silica gel column chromatography and eluted stepwise with many solvent systems. The active fractions were tested with B. subtilis NCTC10400. The purification of the antibiotic has been carried out by thin layer chromatography then the physical and chemical properties were studied to identify the antimicrobial agent. The isolated antimicrobial agent is an antibiotic belonging to the neomycin group. (author)

Chemically-functionalized microcantilevers for detection of chemical, biological and explosive material

Science.gov (United States)

Pinnaduwage, Lal A [Knoxville, TN; Thundat, Thomas G [Knoxville, TN; Brown, Gilbert M [Knoxville, TN; Hawk, John Eric [Olive Branch, MS; Boiadjiev, Vassil I [Knoxville, TN

2007-04-24

A chemically functionalized cantilever system has a cantilever coated on one side thereof with a reagent or biological species which binds to an analyte. The system is of particular value when the analyte is a toxic chemical biological warfare agent or an explosive.

Improving the risk assessment of lipophilic persistent environmental chemicals in breast milk

Science.gov (United States)

BACKGROUND: A breastfeeding infant’s intake of persistent organic pollutants (POPs) may be much greater than his/her mother’s average daily POP exposure. In many cases, current human health risk assessment methods do not account for differences between maternal and infant POP exp...

Detoxification of organophosphate nerve agents by bacterial phosphotriesterase

International Nuclear Information System (INIS)

Ghanem, Eman; Raushel, Frank M.

2005-01-01

Organophosphates have been widely used as insecticides and chemical warfare agents. The health risks associated with these agents have necessitated the need for better detoxification and bioremediation tools. Bacterial enzymes capable of hydrolyzing the lethal organophosphate nerve agents are of special interest. Phosphotriesterase (PTE) isolated from the soil bacteria Pseudomonas diminuta displays a significant rate enhancement and substrate promiscuity for the hydrolysis of organophosphate triesters. Directed evolution and rational redesign of the active site of PTE have led to the identification of new variants with enhanced catalytic efficiency and stereoselectivity toward the hydrolysis of organophosphate neurotoxins. PTE has been utilized to protect against organophosphate poisoning in vivo. Biotechnological applications of PTE for detection and decontamination of insecticides and chemical warfare agents are developing into useful tools. In this review, the catalytic properties and potential applications of this remarkable enzyme are discussed

CEST and PARACEST MR contrast agents

International Nuclear Information System (INIS)

Hancu, Ileana; Dixon, W. Thomas; Woods, Mark; Sherry, A. Dean; Vinogradov, Elena; Lenkinski, Robert E.

2010-01-01

In this review we describe the status of development for a new class of magnetic resonance (MR) contrast agents, based on chemical exchange saturation transfer (CEST). The mathematics and physics relevant to the description of the CEST effect in MR are presented in an appendix published in the online version only. We discuss the issues arising when translating in vitro results obtained with CEST agents to using these MR agents in in vivo model studies and in humans. Examples are given on how these agents are imaged in vivo. We summarize the status of development of these CEST agents, and speculate about the next steps that may be taken towards the demonstration of CEST MR imaging in clinical applications

Persistence of DNA adducts, hypermutation and acquisition of cellular resistance to alkylating agents in glioblastoma.

Science.gov (United States)

Head, R J; Fay, M F; Cosgrove, L; Y C Fung, K; Rundle-Thiele, D; Martin, J H

2017-12-02

Glioblastoma is a lethal form of brain tumour usually treated by surgical resection followed by radiotherapy and an alkylating chemotherapeutic agent. Key to the success of this multimodal approach is maintaining apoptotic sensitivity of tumour cells to the alkylating agent. This initial treatment likely establishes conditions contributing to development of drug resistance as alkylating agents form the O 6 -methylguanine adduct. This activates the mismatch repair (MMR) process inducing apoptosis and mutagenesis. This review describes key juxtaposed drivers in the balance between alkylation induced mutagenesis and apoptosis. Mutations in MMR genes are the probable drivers for alkylation based drug resistance. Critical to this interaction are the dose-response and temporal interactions between adduct formation and MMR mutations. The precision in dose interval, dose-responses and temporal relationships dictate a role for alkylating agents in either promoting experimental tumour formation or inducing tumour cell death with chemotherapy. Importantly, this resultant loss of chemotherapeutic selective pressure provides opportunity to explore novel therapeutics and appropriate combinations to minimise alkylation based drug resistance and tumour relapse.

Modified clay minerals efficiency against chemical and biological warfare agents for civil human protection.

Science.gov (United States)

Plachá, Daniela; Rosenbergová, Kateřina; Slabotínský, Jiří; Kutláková, Kateřina Mamulová; Studentová, Soňa; Martynková, Gražyna Simha

2014-04-30

Sorption efficiencies of modified montmorillonite and vermiculite of their mono ionic Na and organic HDTMA and HDP forms were studied against chemical and biological warfare agents such as yperite and selected bacterial strains. Yperite interactions with modified clay minerals were observed through its capture in low-density polyethylene foil-modified clay composites by measuring yperite gas permeation with using chemical indication and gas chromatography methods. The antibacterial activities of synthetized organoclays were tested against selected Gram-positive and Gram-negative bacterial species in minimum inhibitory concentration tests. The obtained results showed a positive influence of modified clay minerals on the significant yperite breakthrough-time increase. The most effective material was the polyethylene-Na form montmorillonite, while the polyethylene-Na form vermiculite showed the lowest efficiency. With increasing organic cations loading in the interlayer space the montmorillonite efficiency decreased, and in the case of vermiculite an opposite effect was observed. Generally the modified montmorillonites were more effective than modified vermiculites. The HDP cations seem to be more effective compare to the HDTMA. The antibacterial activity tests confirmed efficiency of all organically modified clay minerals against Gram-positive bacteria. The confirmation of antibacterial activity against Y. pestis, plague bacteria, is the most interesting result of this part of the study. Copyright © 2014 Elsevier B.V. All rights reserved.

Oxidation of the persistent compounds in the oxygen-hydrogen plasma

International Nuclear Information System (INIS)

Brozek, V.; Novak, M.; Vonka, P.; Kopecky, V.; Hrabovsky, M.

1995-01-01

The effectiveness of plasma-chemical decomposition of the persistent halogenated aliphatic hydrocarbons (CCl 4 , CF 2 Cl 2 , CF 3 Cl 3 and C 6 Cl 6 ) was examined by the analysis of emergent products in the dependence on the next parameters of the plasma-chemical reactor: power of the plasmatron; geometry of the plasmatic cone; velocity of flow of the gases by reaction chamber; stoichiometry of the ratio of the oxygen-air-water

Lesão aguda esôfago - gástrica causada por agente químico Chemically induced esophagogastric acute injury

Directory of Open Access Journals (Sweden)

P. R. Corsi

2000-06-01

Full Text Available O tratamento da ingestão de agentes químicos corrosivos continua controverso. A incidência desses episódios tem aumentado nas últimas décadas por várias razões. OBJETIVO: Analisar a ocorrência, as complicações e os resultados do tratamento da lesão esôfago - gástrica causada por agentes químicos. MÉTODOS: Foram estudados retrospectivamente 21 pacientes adultos com lesão esôfago-gástrica, causada por ingestão de substância química, admitidos até 23 dias após o episódio, no Serviço de Emergência da Santa Casa de Misericórdia de São Paulo num período de 12 anos. A média de idade foi 32,1 anos e 11 doentes pertenciam ao sexo feminino, as quais mais freqüentemente tinham intenções suicidas. A soda cáustica foi o produto mais ingerido (76,2%, ingestão de ácido muriático ocorreu em três casos (14,3%, amoníaco e ácido sulfúrico em um caso (4,8% cada. RESULTADOS: As lesões faríngeas e laríngeas estiveram freqüentemente associadas às lesões de esôfago, presentes em 18 casos (85,7%. As lesões esofágicas, gástricas e duodenais foram avaliadas e classificadas por endoscopia. Lesões graves esofágicas ou gástricas estiveram presentes em cinco casos cada. CONCLUSÃO: O tratamento e os resultados foram variados, mas sugeriram que a sondagem esofágica foi prejudicial. A mortalidade global foi 28,6%, mais elevada na lesão esofágica grau 3.Treatment of chemical agent ingestion remain controversial. The incidence of these episodes has increased over the several last decades due to a variety reasons. PURPOSE: To analise the occurance, complications and results of the treatment of chemically induced esophagogastric injury. METHODS: Twenty-one adult patients with chemically induced esophagogastric injury were retrospectively studied. The patients were admitted up to 23 days after ingestion of a chemical agent to the Emergency Department of Santa Casa of Sao Paulo University Hospital from August, in a 12-year

Detecting Chemical Weapons: Threats, Requirements, Solutions, and Future Challenges

Science.gov (United States)

Boso, Brian

2011-03-01

Although chemicals have been reportedly used as weapons for thousands of years, it was not until 1915 at Ypres, France that an industrial chemical, chlorine, was used in World War I as an offensive weapon in significant quantity, causing mass casualties. From that point until today the development, detection, production and protection from chemical weapons has be an organized endeavor of many of the world's armed forces and in more recent times, non-governmental terrorist organizations. The number of Chemical Warfare Agents (CWAs) has steadily increased as research into more toxic substances continued for most of the 20 th century. Today there are over 70 substances including harassing agents like tear gas, incapacitating agents, and lethal agents like blister, blood, chocking, and nerve agents. The requirements for detecting chemical weapons vary depending on the context in which they are encountered and the concept of operation of the organization deploying the detection equipment. The US DoD, for example, has as a requirement, that US forces be able to continue their mission, even in the event of a chemical attack. This places stringent requirements on detection equipment. It must be lightweight (developed for this application, including, but not limited to: mass spectroscopy, IR spectroscopy, RAMAN spectroscopy, MEMs micro-cantilever sensors, surface acoustic wave sensors, differential mobility spectrometry, and amplifying fluorescence polymers. In the future the requirements for detection equipment will continue to become even more stringent. The continuing increase in the sheer number of threats that will need to be detected, the development of binary agents requiring that even the precursor chemicals be detected, the development of new types of agents unlike any of the current chemistries, and the expansion of the list of toxic industrial chemical will require new techniques with higher specificity and more sensitivity.

Assumed non-persistent environmental chemicals in human adipose tissue; matrix stability and correlation with levels measured in urine and serum.

Science.gov (United States)

Artacho-Cordón, F; Arrebola, J P; Nielsen, O; Hernández, P; Skakkebaek, N E; Fernández, M F; Andersson, A M; Olea, N; Frederiksen, H

2017-07-01

The aim of this study was to (1) optimize a method for the measurement of parabens and phenols in adipose tissue, (2) evaluate the stability of chemical residues in adipose tissue samples, and (3) study correlations of these compounds in urine, serum, and adipose tissue. Samples were obtained from adults undergoing trauma surgery. Nine phenols and seven parabens were determined by isotope diluted TurboFlow-LC-MS/MS. The analytical method showed good accuracy and precision. Limits of detection (LOD) for parabens and phenols ranged from 0.05 to 1.83ng/g tissue. Good recovery rates were found, even when biological samples remained defrosted up to 24h. Benzophenone-3 (BP-3; range of values: 70% of adipose tissue samples, while bisphenol-A (BPA; 40% of adipose tissue samples. In general, levels were similar between adipose tissue and serum, while a correlation between adipose tissue and urine was only found for BP-3. In conclusion, adipose tissue samples in this study were found to contain environmental chemicals considered to be non-persistent, whose levels were weakly or not at all correlated with the urine burden. Therefore, adipose tissue may potentially provide additional information to that obtained from other biological matrices. Further investigations are warranted to explore whether adipose tissue might be a suitable matrix for assessment of the consequences for human health of mid/long-term exposure to these chemicals. Copyright © 2017 Elsevier Inc. All rights reserved.

Environmental Effects on Zirconium Hydroxide Nanoparticles and Chemical Warfare Agent Decomposition: Implications of Atmospheric Water and Carbon Dioxide.

Science.gov (United States)

Balow, Robert B; Lundin, Jeffrey G; Daniels, Grant C; Gordon, Wesley O; McEntee, Monica; Peterson, Gregory W; Wynne, James H; Pehrsson, Pehr E

2017-11-15

Zirconium hydroxide (Zr(OH) 4 ) has excellent sorption properties and wide-ranging reactivity toward numerous types of chemical warfare agents (CWAs) and toxic industrial chemicals. Under pristine laboratory conditions, the effectiveness of Zr(OH) 4 has been attributed to a combination of diverse surface hydroxyl species and defects; however, atmospheric components (e.g., CO 2 , H 2 O, etc.) and trace contaminants can form adsorbates with potentially detrimental impact to the chemical reactivity of Zr(OH) 4 . Here, we report the hydrolysis of a CWA simulant, dimethyl methylphosphonate (DMMP) on Zr(OH) 4 determined by gas chromatography-mass spectrometry and in situ attenuated total reflectance Fourier transform infrared spectroscopy under ambient conditions. DMMP dosing on Zr(OH) 4 formed methyl methylphosphonate and methoxy degradation products on free bridging and terminal hydroxyl sites of Zr(OH) 4 under all evaluated environmental conditions. CO 2 dosing on Zr(OH) 4 formed adsorbed (bi)carbonates and interfacial carbonate complexes with relative stability dependent on CO 2 and H 2 O partial pressures. High concentrations of CO 2 reduced DMMP decomposition kinetics by occupying Zr(OH) 4 active sites with carbonaceous adsorbates. Elevated humidity promoted hydrolysis of adsorbed DMMP on Zr(OH) 4 to produce methanol and regenerated free hydroxyl species. Hydrolysis of DMMP by Zr(OH) 4 occurred under all conditions evaluated, demonstrating promise for chemical decontamination under diverse, real-world conditions.

Equilibrium sampling to determine the thermodynamic potential for bioaccumulation of persistent organic pollutants from sediment.

Science.gov (United States)

Jahnke, Annika; MacLeod, Matthew; Wickström, Håkan; Mayer, Philipp

2014-10-07

Equilibrium partitioning (EqP) theory is currently the most widely used approach for linking sediment pollution by persistent hydrophobic organic chemicals to bioaccumulation. Most applications of the EqP approach assume (I) a generic relationship between organic carbon-normalized chemical concentrations in sediments and lipid-normalized concentrations in biota and (II) that bioaccumulation does not induce levels exceeding those expected from equilibrium partitioning. Here, we demonstrate that assumption I can be obviated by equilibrating a silicone sampler with chemicals in sediment, measuring chemical concentrations in the silicone, and applying lipid/silicone partition ratios to yield concentrations in lipid at thermodynamic equilibrium with the sediment (CLip⇌Sed). Furthermore, we evaluated the validity of assumption II by comparing CLip⇌Sed of selected persistent, bioaccumulative and toxic pollutants (polychlorinated biphenyls (PCBs) and hexachlorobenzene (HCB)) to lipid-normalized concentrations for a range of biota from a Swedish background lake. PCBs in duck mussels, roach, eel, pikeperch, perch and pike were mostly below the equilibrium partitioning level relative to the sediment, i.e., lipid-normalized concentrations were ≤CLip⇌Sed, whereas HCB was near equilibrium between biota and sediment. Equilibrium sampling allows straightforward, sensitive and precise measurement of CLip⇌Sed. We propose CLip⇌Sed as a metric of the thermodynamic potential for bioaccumulation of persistent organic chemicals from sediment useful to prioritize management actions to remediate contaminated sites.

Ciprofloxacin causes persister formation by inducing the TisB toxin in Escherichia coli.

Directory of Open Access Journals (Sweden)

Tobias Dörr

2010-02-01

Full Text Available Bacteria induce stress responses that protect the cell from lethal factors such as DNA-damaging agents. Bacterial populations also form persisters, dormant cells that are highly tolerant to antibiotics and play an important role in recalcitrance of biofilm infections. Stress response and dormancy appear to represent alternative strategies of cell survival. The mechanism of persister formation is unknown, but isolated persisters show increased levels of toxin/antitoxin (TA transcripts. We have found previously that one or more components of the SOS response induce persister formation after exposure to a DNA-damaging antibiotic. The SOS response induces several TA genes in Escherichia coli. Here, we show that a knockout of a particular SOS-TA locus, tisAB/istR, had a sharply decreased level of persisters tolerant to ciprofloxacin, an antibiotic that causes DNA damage. Step-wise administration of ciprofloxacin induced persister formation in a tisAB-dependent manner, and cells producing TisB toxin were tolerant to multiple antibiotics. TisB is a membrane peptide that was shown to decrease proton motive force and ATP levels, consistent with its role in forming dormant cells. These results suggest that a DNA damage-induced toxin controls production of multidrug tolerant cells and thus provide a model of persister formation.

Chemical Vapor Transport Deposition of Molybdenum Disulfide Layers Using H2O Vapor as the Transport Agent

Directory of Open Access Journals (Sweden)

Shichao Zhao

2018-02-01

Full Text Available Molybdenum disulfide (MoS2 layers show excellent optical and electrical properties and have many potential applications. However, the growth of high-quality MoS2 layers is a major bottleneck in the development of MoS2-based devices. In this paper, we report a chemical vapor transport deposition method to investigate the growth behavior of monolayer/multi-layer MoS2 using water (H2O as the transport agent. It was shown that the introduction of H2O vapor promoted the growth of MoS2 by increasing the nucleation density and continuous monolayer growth. Moreover, the growth mechanism is discussed.

Rotenone persistence model for montane streams

Science.gov (United States)

Brown, Peter J.; Zale, Alexander V.

2012-01-01

The efficient and effective use of rotenone is hindered by its unknown persistence in streams. Environmental conditions degrade rotenone, but current label instructions suggest fortifying the chemical along a stream based on linear distance or travel time rather than environmental conditions. Our objective was to develop models that use measurements of environmental conditions to predict rotenone persistence in streams. Detailed measurements of ultraviolet radiation, water temperature, dissolved oxygen, total dissolved solids (TDS), conductivity, pH, oxidation–reduction potential (ORP), substrate composition, amount of organic matter, channel slope, and travel time were made along stream segments located between rotenone treatment stations and cages containing bioassay fish in six streams. The amount of fine organic matter, biofilm, sand, gravel, cobble, rubble, small boulders, slope, pH, TDS, ORP, light reaching the stream, energy dissipated, discharge, and cumulative travel time were each significantly correlated with fish death. By using logistic regression, measurements of environmental conditions were paired with the responses of bioassay fish to develop a model that predicted the persistence of rotenone toxicity in streams. This model was validated with data from two additional stream treatment reaches. Rotenone persistence was predicted by a model that used travel time, rubble, and ORP. When this model predicts a probability of less than 0.95, those who apply rotenone can expect incomplete eradication and should plan on fortifying rotenone concentrations. The significance of travel time has been previously identified and is currently used to predict rotenone persistence. However, rubble substrate, which may be associated with the degradation of rotenone by adsorption and volatilization in turbulent environments, was not previously considered.

Characterization of Cu–Ni nanostructured alloys obtained by a chemical route. Influence of the complexing agent content in the starting solution

Energy Technology Data Exchange (ETDEWEB)

Carreras, Alejo C., E-mail: acarreras@famaf.unc.edu.ar [Instituto de Física Enrique Gaviola (IFEG), Facultad de Matemática, Astronomía y Física, Universidad Nacional de Córdoba—CONICET, Medina Allende s/n, Ciudad Universitaria, 5016 Córdoba (Argentina); Cangiano, María de los A.; Ojeda, Manuel W.; Ruiz, María del C. [Instituto de Investigaciones en Tecnología Qumica (INTEQUI), Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis—CONICET, Chacabuco y Pedernera, 5700 San Luis (Argentina)

2015-03-15

The influence of the amount of complexing agent added to the starting solution on the physicochemical properties of Cu–Ni nanostructured alloys obtained through a chemical route, was studied. For this purpose, three Cu–Ni nanoalloy samples were synthesized by a previously developed procedure, starting from solutions with citric acid to metal molar ratios (C/Me) of 0.73, 1.00 and 1.50. The synthesis technique consisted in preparing a precursor via the citrate-gel method, and carrying out subsequent thermal treatments in controlled atmospheres. Sample characterization was performed by scanning electron microscopy, X-ray microanalysis, X-ray diffraction, transmission electron microscopy, X-ray nanoanalysis and electron diffraction. In the three cases, copper and nickel formed a solid solution with a Cu/Ni atomic ratio close to 50/50, and free of impurities inside the crystal structure. The citric acid content of the starting solution proved to have an important influence on the morphology, size distribution, porosity, and crystallinity of the Cu–Ni alloy microparticles obtained, but a lesser influence on their chemical composition. The molar ratio C/Me = 1.00 resulted in the alloy with the Cu/Ni atomic ratio closest to 50/50. - Highlights: • We synthesize Cu–Ni nanoalloys by a chemical route based on the citrate-gel method. • We study the influence of the complexing agent content of the starting solution. • We characterize the samples by electron microscopy and X-ray techniques. • Citric acid influences the shape, size, porosity and crystallinity of the alloys.

Effect of fluorescent pseudomonades and Trichoderma sp. and their combination with two chemicals on Penicillium digitatum caused agent of citrus green mold.

Science.gov (United States)

Zamani, M; Tehrani, A Sharifi; Ahmadzadeh, M; Abadi, A Alizadeh Ali

2006-01-01

Citrus green mold (Penicillium digitatum) causes economic losses. Chemical fungicides such as imazalil provide the primary means for controlling green mold decay of citrus fruits. Continuous use of fungicides has faced two major obstacles- increasing public concern regarding contamination of perishables with fungicidal residues, and proliferation of resistance in the pathogen populations. The aim of this research was to determine if the attacks of green mold on orange could be reduced by usage of biocontrol agent alone or in combination with low dosage of imazalil or sodium bicarbonate. Pseudomonas fluorescens isolate PN, P. fluorescens isolate PS and Trichoderma virens isolate TE were evaluated as potential biological agents for control of green mold of oranges caused by P. digitatum. Increasing concentration of SB decreased spore germination of P. digitatum. In laboratory tests, a cell suspension (10(8) cells per ml.) of bacterial strains reduced the incidence of green mold. On fruits surface biocontrol activity of antagonistic isolates was significantly increased when combined with low dosage of imazalil (500ppm) or sodium carbonate (5%). Effect of Trichoderma virens on controlling P. digitatum was better than others with or without these chemicals.

Fast and Sustained Degradation of Chemical Warfare Agent Simulants Using Flexible Self-Supported Metal-Organic Framework Filters.

Science.gov (United States)

Liang, Huixin; Yao, Aonan; Jiao, Xiuling; Li, Cheng; Chen, Dairong

2018-06-20

Self-detoxification filters against lethal chemical warfare agents (CWAs) are highly desirable for the protection of human beings and the environment. In this report, flexible self-supported filters of a series of Zr(IV)-based metal-organic frameworks (MOFs) including UiO-66, UiO-67, and UiO-66-NH 2 were successfully prepared and exhibited fast and sustained degradation of CWA simulants. A half-life as short as 2.4 min was obtained for the catalytic hydrolysis of dimethyl 4-nitrophenyl phosphate, and the percent conversion remained above 90% over a long-term exposure of 120 min, well exceeding those of the previously reported composite MOF filters and the corresponding MOF powders. The outstanding detoxification performance of the self-supported fibrous filter comes from the exceptionally high surface area, excellent pore accessibility, and hierarchical structure from the nano- to macroscale. This work demonstrates, for the first time, MOF-only filters as efficient self-detoxification media, which will offer new opportunities for the design and fabrication of functional materials for toxic chemical protection.

A biomarker-responsive T2ex MRI contrast agent.

Science.gov (United States)

Daryaei, Iman; Randtke, Edward A; Pagel, Mark D

2017-04-01

This study investigated a fundamentally new type of responsive MRI contrast agent for molecular imaging that alters T 2 exchange (T 2ex ) properties after interacting with a molecular biomarker. The contrast agent Tm-DO3A-oAA was treated with nitric oxide (NO) and O 2 . The R 1 and R 2 relaxation rates of the reactant and product were measured with respect to concentration, temperature, and pH. Chemical exchange saturation transfer (CEST) spectra of the reactant and product were acquired using a 7 Tesla (T) MRI scanner and analyzed to estimate the chemical exchange rates and r 2ex relaxivities. The reaction of Tm-DO3A-oAA with NO and O 2 caused a 6.4-fold increase in the r 2 relaxivity of the agent, whereas r 1 relaxivity remained unchanged, which demonstrated that Tm-DO3A-oAA is a responsive T 2ex agent. The effects of pH and temperature on the r 2 relaxivities of the reactant and product supported the conclusion that the product's benzimidazole ligand caused the agent to have a fast chemical exchange rate relative to the slow exchange rate of the reactant's ortho-aminoanilide ligand. T 2ex MRI contrast agents are a new type of responsive agent that have good detection sensitivity and specificity for detecting a biomarker, which can serve as a new tool for molecular imaging. Magn Reson Med 77:1665-1670, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

Integrated approaches for determination of environmental and human risks of persistent toxic substances

International Nuclear Information System (INIS)

Blaha, L.; Cupr, P.; Dusek, L.; Hilscherova, K.; Holoubek, I.; Klanova, J.

2008-01-01

Substances that are persistent and bioaccumulative often posses toxic characteristics and cause adverse human health or environmental effects. Basic objective of the long-term research project INCHEMBIOL undertaken by the Centre RECETOX are the complex studies of interactions among chemical compounds present in environmental compartments and their biological effects and studies of the fate of mainly persistent chemical compounds in the environment, their effects on the environment and living organisms including human. Destiny in this concept consists of a summary of transport (from their input in the environment, transport within the environmental compartment, where they are discharged, transport among compartments and long-range transport in the environment) and transformation processes (abiotic and biotic transformations). It also includes study of distribution equilibriums, properties conditioning their environmental behaviour, study of the transformation processes and their products. This complex approach is a part of long-term research activities of the centre RECETOX. In the contribution methods used and results obtained in exploration of the causality among chemical (presence of chemical compounds in the environment) and biological (mechanisms of effects on the living organisms) are described.

New set of Chemical Safety rules

CERN Multimedia

HSE Unit

2011-01-01

A new set of four Safety Rules was issued on 28 March 2011: Safety Regulation SR-C ver. 2, Chemical Agents (en); General Safety Instruction GSI-C1, Prevention and Protection Measures (en); General Safety Instruction GSI-C2, Explosive Atmospheres (en); General Safety Instruction GSI-C3, Monitoring of Exposure to Hazardous Chemical Agents in Workplace Atmospheres (en). These documents form part of the CERN Safety Rules and are issued in application of the “Staff Rules and Regulations” and of document SAPOCO 42. These documents set out the minimum requirements for the protection of persons from risks to their occupational safety and health arising, or likely to arise, from the effects of hazardous chemical agents that are present in the workplace or used in any CERN activity. Simultaneously, the HSE Unit has published seven Safety Guidelines and six Safety Forms. These documents are available from the dedicated Web page “Chemical, Cryogenic and Biological Safety&...

Morphological and chemical changes in dentin after using endodontic agents: Fourier transform Raman spectroscopy, energy-dispersive x-ray fluorescence spectrometry, and scanning electron microscopy study

Science.gov (United States)

Pascon, Fernanda Miori; Kantovitz, Kamila Rosamilia; Soares, Luís Eduardo Silva; Santo, Ana Maria do Espírito; Martin, Airton Abraha~o.; Puppin-Rontani, Regina Maria

2012-07-01

We examine the morphological and chemical changes in the pulp chamber dentin after using endodontic agents by scanning electron microscopy (SEM), Fourier transform Raman spectroscopy (FT-Raman), and micro energy-dispersive x-ray fluorescence spectrometry (μEDXRF). Thirty teeth were sectioned exposing the pulp chamber and divided by six groups (n=5): NT-no treatment; CHX-2% chlorhexidine; CHXE-2% chlorhexidine+17% EDTA E-17% EDTA; SH5-5.25% NaOCl; SH5E-5.25% NaOCl+17% EDTA. The inorganic and organic content was analyzed by FT-Raman. μEDXRF examined calcium (Ca) and phosphorus (P) content as well as Ca/P ratio. Impressions of specimens were evaluated by SEM. Data were submitted to Kruskal-Wallis and Dunn tests (pNT=SH5E>CHX>E>CHXE). CHXE and E presented the highest Ca/P ratio values compared to the other groups (p<0.05). The SEM images in the EDTA-treated groups had the highest number of open tubules. Erosion in the tubules was observed in CHX and SH5E groups. Endodontic agents change the inorganic and organic content of pulp chamber dentin. NaOCl used alone, or in association with EDTA, was the most effective agent considering chemical and morphological approaches.

Used tire recycling to produce granulates: evaluation of occupational exposure to chemical agents.

Science.gov (United States)

Savary, Barbara; Vincent, Raymond

2011-10-01

Exposure was assessed in four facilities where used tires are turned into rubber granulates. Particulate exposure levels were measured using filter samples and gravimetric analysis. In parallel, volatile organic compounds (VOCs) screening was carried out using samples taken on activated carbon supports, followed by an analysis using a gas chromatograph coupled to a spectrometric detector. The exposure level medians are between 0.58 and 3.95 mg m(-3). Clogging of the textile fiber separation systems can lead to worker exposure; in this case, the measured concentrations can reach 41 mg m(-3). However, in contrast to the data in the literature, VOC levels >1 p.p.m. were not detected. The particulate mixtures deposited on the installation surfaces are complex; some of the chemical agents are toxic to humans. The results of this study indicate significant exposure to complex mixtures of rubber dust. Optimizing exhaust ventilation systems inside the shredders, with a cyclone for example, is essential for reducing the exposure of workers in this rapidly developing sector.

Multiscale modeling of nerve agent hydrolysis mechanisms: a tale of two Nobel Prizes

Science.gov (United States)

Field, Martin J.; Wymore, Troy W.

2014-10-01

The 2013 Nobel Prize in Chemistry was awarded for the development of multiscale models for complex chemical systems, whereas the 2013 Peace Prize was given to the Organisation for the Prohibition of Chemical Weapons for their efforts to eliminate chemical warfare agents. This review relates the two by introducing the field of multiscale modeling and highlighting its application to the study of the biological mechanisms by which selected chemical weapon agents exert their effects at an atomic level.

Development of haemostatic decontaminants for treatment of wounds contaminated with chemical warfare agents. 3: Evaluation of in vitro topical decontamination efficacy using damaged skin.

Science.gov (United States)

Lydon, Helen L; Hall, Charlotte A; Dalton, Christopher H; Chipman, J Kevin; Graham, John S; Chilcott, Robert P

2017-08-01

Previous studies have demonstrated that haemostatic products with an absorptive mechanism of action retain their clotting efficiency in the presence of toxic materials and are effective in decontaminating chemical warfare (CW) agents when applied to normal, intact skin. The purpose of this in vitro study was to assess three candidate haemostatic products for effectiveness in the decontamination of superficially damaged porcine skin exposed to the radiolabelled CW agents, soman (GD), VX and sulphur mustard (HD). Controlled physical damage (removal of the upper 100 μm skin layer) resulted in a significant enhancement of the dermal absorption of all three CW agents. Of the haemostatic products assessed, WoundStat™ was consistently the most effective, being equivalent in performance to a standard military decontaminant (fuller's earth). These data suggest that judicious application of haemostatic products to wounds contaminated with CW agents may be a viable option for the clinical management of casualties presenting with contaminated, haemorrhaging injuries. Further studies using a relevant animal model are required to confirm the potential clinical efficacy of WoundStat™ for treating wounds contaminated with CW agents. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Forensic Excavation of Rock Masses: A Technique to Investigate Discontinuity Persistence

Science.gov (United States)

Shang, J.; Hencher, S. R.; West, L. J.; Handley, K.

2017-11-01

True persistence of rock discontinuities (areas with insignificant tensile strength) is an important factor controlling the engineering behaviour of fractured rock masses, but is extremely difficult to quantify using current geological survey methodologies, even where there is good rock exposure. Trace length as measured in the field or using remote measurement devices is actually only broadly indicative of persistence for rock engineering practice and numerical modelling. Visible traces of discontinuities are treated as if they were open fractures within rock mass classifications, despite many such traces being non-persistent and actually retaining considerable strength. The common assumption of 100% persistence, based on trace length, is generally extremely conservative in terms of strength and stiffness, but not always so and may lead to a wrong prediction of failure mechanism or of excavatability. Assuming full persistence would give hopelessly incorrect predictions of hydraulic conductivity. A new technique termed forensic excavation of rock masses is introduced, as a procedure for directly investigating discontinuity persistence. This technique involves non-explosive excavation of rock masses by injecting an expansive chemical splitter along incipient discontinuities. On expansion, the splitter causes the incipient traces to open as true joints. Experiments are described in which near-planar rock discontinuities, through siltstone and sandstone, were opened up by injecting the splitter into holes drilled along the lines of visible traces of the discontinuities in the laboratory and in the field. Once exposed the surfaces were examined to investigate the pre-existing persistence characteristics of the incipient discontinuities. One conclusion from this study is that visible trace length of a discontinuity can be a poor indicator of true persistence (defined for a fracture area with negligible tensile strength). An observation from this series of experiments