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Rainer Haas - One of the best experts on this subject based on the ideXlab platform.
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Chemische Reaktionen von chlorvinylarsinverbindungen (Lewisite)
Umweltwissenschaften und Schadstoff-Forschung, 1998Co-Authors: Rainer HaasAbstract:2-Chlorovinylarsine dichloride (Lewisite I) and 2,2′-dichlorodivinylarsine chloride (Lewisite II) react by room temperature rapidly and quantitatively with dithiols in a substitution reaction. The derivatives were identified with mass spectrometry. They can be detected with GC/ECD. This reactions can be used for the gas chromatographic detection of Lewisites in water and soil samples. 2-Chlorvinylarsindichlorid (Lewisit I) und 2,2′-Dichlordivinylarsinchlorid (Lewisit II) reagieren bei Raumtemperatur in einer Substitutionsreaktion schnell und quantitativ mit Dithiolen. Die Derivate wurden massenspetrometrisch identifiziert. Sie sind mit GC/ECD detektierbar. Diese Reaktionen können zur gaschromatographischen Bestimmung von Lewisiten in Wasser-und Bodenproben eingesetzt werden.
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chemische reaktionen von chlorvinylarsinverbindungen Lewisite chemical reactions of chlorovinylarsines Lewisite 3 reaction of Lewisite i and Lewisite ii with dithiols 3 reaktion von lewisit i und lewisit ii mit dithiolen
Umweltwissenschaften Und Schadstoff-forschung, 1998Co-Authors: Rainer HaasAbstract:2-Chlorovinylarsine dichloride (Lewisite I) and 2,2′-dichlorodivinylarsine chloride (Lewisite II) react by room temperature rapidly and quantitatively with dithiols in a substitution reaction. The derivatives were identified with mass spectrometry. They can be detected with GC/ECD. This reactions can be used for the gas chromatographic detection of Lewisites in water and soil samples.
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Chemische Reaktionen von Chlorvinylarsinverbindungen (Lewisite)
Umweltwissenschaften und Schadstoff-Forschung, 1998Co-Authors: Rainer Haas, Alfred KrippendorfAbstract:2-Chlorvinylarsindichlorid (Lewisit I) reagiert bei Raumtemperatur in einer Gleichgewichtsreaktion schnell mit Alkoholen unter Bildung von 2-Chlorvinylarsinchloridether und 2-Chlorvinylarsinbisether. Die Reaktionen verlaufen nicht quantitativ. Die Ethyl-und Propylether sind nicht stabil. Die Ether wurden massenspektrometrisch identifiziert. 2-Chlorovinylarsine dichloride (Lewisite I) react by room temperature quickly with alcohols in an equilibrium reaction to yield 2-Chlorovinylarsine chloride ether and 2-Chlorovinylarsine bisether. The reactions are not quantitative. The ethyl- and propylether are not stable. The ether were identified with mass spectrometry.
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Determination of chemical warfare agents
Environmental Science and Pollution Research, 1998Co-Authors: Rainer HaasAbstract:Chlorovinylannes (Lewisites) were produced and handled during WW I and WW II as chemical warfare agents. Residues of these cwa and their metabolites are still present today and continue to contaminate soil and water. A gas Chromatographic method for the detection and determination of chlorovinylarsines (Lewisites) and their metabolites is shown. Lewisite II and Lewisite III, but not Lewisite I and the metabolites of Lewisite I and Lewisite II can be detected and determined using GC/ECD. After derivatization with thiols, the sum of Lewisite I or Lewisite II and their metabolites are detected. With the proper selection of the thiol, matrix interferences can be eliminated because of the different retention times of the derivatives.
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Chemische Reaktionen von Chlorvinylarsinverbindungen (Lewisit)
Umweltwissenschaften und Schadstoff-Forschung, 1998Co-Authors: Rainer Haas, Alfred Krippendorf, Klaus SteinbachAbstract:2,2′-Dichlordivinylarsinchlorid (Lewisit II) reagiert bei Raumtemperatur in einer Gleichgewichtstreaktion schnell mit Alkoholen unter Bildung von 2,2′-Dichlordivinylarsinether. Die Reaktionen verlaufen nicht quantitativ. Die Methyl-, Ethyl-und Propylether sind nicht stabil. 2,2′-Dichlorodivinylarsine chloride (Lewisite II) react by room temperature quickly with alcohols in an equilibrium reaction to yield 2,2′-Dichlorodivinylarsine ether. The reactions are not quantitative. The methyl-, ethyl-and propylether are not stable.
Christopher M. Timperley - One of the best experts on this subject based on the ideXlab platform.
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Determination of Lewisite constituents in aqueous samples using hollow-fibre liquid-phase microextraction followed by gas chromatography-mass spectrometry
Analytical and Bioanalytical Chemistry, 2014Co-Authors: M. Y. Cheh, H. C. Chua, F. B. Hopkins, J. R. Riches, Christopher M. TimperleyAbstract:The applicability of hollow-fibre liquid-phase microextraction for extracting 2-chlorovinyldichloroarsine (Lewisite 1), bis(2-chlorovinyl)chloroarsine (Lewisite 2), tris(2-chlorovinyl)arsine (Lewisite 3) and arsenic trichloride from aqueous samples is reported. Parameters affecting the extraction efficiency of these chemicals were optimised. These parameters included the type of derivatising agent, extraction solvent, derivatisation method, pH, ionic strength, stirring speed and extraction time. A linear range between 0.002 and 0.2 μg/mL was established for the Lewisites with good square regression coefficients (0.9955–0.9992). Good reproducibility with relative standard deviations (RSDs) from 8 to 10 % was achieved. The limit of detection was 0.002 μg/mL for the Lewisites and 0.005 μg/mL for arsenic trichloride (3:1 signal-to-noise ratio). The extraction method was validated with a proficiency test sample issued by the Organisation for the Prohibition of Chemical Weapons (OPCW). The rapidity and precision of the new method should help deter against the employment of Lewisite as a chemical warfare agent: its use could be confirmed easily from analysis of aqueous samples.
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analysis of chemical warfare agents i use of aliphatic thiols in the trace level determination of Lewisite compounds in complex matrices
Journal of Chromatography A, 2005Co-Authors: Bob Muir, Ben J Slater, David B Cooper, Christopher M. TimperleyAbstract:Abstract A series of normal aliphatic thiols have been used to derivatise the chemical warfare agents Lewisites I and II (LI and LII) in hydrocarbon matrices. Varying the chain length of the thiol allowed adjustment of derivative t R by 5.9 min for Lewisite I and 5.3 min for Lewisite II. Linear regression analysis of the chain length of the thiol derivatives of the Lewisite species, and that of a series of normal alkanes against t R , allowed regression models to be developed for each set of compounds. Application of the models allowed thiol reagents to be chosen to give derivatives of Lewisites I and II that eluted before and after the major hydrocarbon contaminant. Limits of detection were comparable for all thiol derivatives analysed by GC–MS in the selection ion monitoring mode (all below 1 μg ml −1 ). The robustness of this approach was illustrated by successful identification of Lewisite I in samples from the Sixth Proficiency Test (organised by the Organisation for the Prohibition of Chemical Weapons, OPCW) in a matrix of 1 mg ml −1 diesel oil.
J C Dacre - One of the best experts on this subject based on the ideXlab platform.
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two generation reproduction study of Lewisite in rats
Journal of Applied Toxicology, 1999Co-Authors: L B Sasser, J A Cushing, C W Lindenmeier, P W Mellick, J C DacreAbstract:Lewisite, a potent toxic vesicant and chemical warfare agent, is used in a number of research laboratories, is stored in large quantities at depot sites throughout the USA and is occasionally transported to distant sites. Thus, the potential for environmental or occupational exposure exists where Lewisite is present. A 42-week two-generation study was conducted to determine the reproductive consequences of Lewisite in parental male and female rats and their offspring. Rats were administered Lewisite in sesame oil (0, 0.10, 0.25 or 0.60 mg kg -1 day -1 for 5 days a week) via intragastic intubation before mating, during mating and after mating until the birth of their offspring. The dams continued to receive Lewisite during lactation. At weaning, male and female offspring of each group were selected to continue the study, receiving Lewisite during adolescence, mating and throughout gestation and lactation. Lewisite had no adverse effect on reproduction performance, fertility or reproductive organ weights of male or female rats through two consecutive generations. No adverse effects to offspring were attributed to Lewisite exposure. Minor changes in growth were the only maternal effects observed. Lewisite exposure of parental rats caused no gross or microscopic lesion in testes, epididymis, prostate, seminal vesicles, ovaries, uterus or vagina. The no-observable-effect level (NOEL) for the reproductive effects of Lewisite would be >0.60 mg kg -1 day -1 .
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subchronic toxicity evaluation of Lewisite in rats
Journal of Toxicology and Environmental Health, 1996Co-Authors: L B Sasser, J A Cushing, P W Mellick, D. R. Kalkwarf, J C DacreAbstract:Health and exposure criteria have not been established for Lewisite [dichloro(2-chlorovinyl) arsine], a potent toxic vesicant that reacts with the sulfhydryl groups of proteins through its arsenic group. Sixty Sprague-Dawley rats of each sex, 6-7 wk old, were divided into 6 groups (10/group/sex) and gavaged with either 0, 0.01, 0.1, 0.5, 1.0, or 2.0 m g/kg of Lewisite in sesame oil 5 d/wk for 13 wk. No significant dose-related change in body weight was observed. At the high dose, serum protein, creatinine, SGOT, and SGPT were decreased in males; lymphocytes and platelets were increased in females. A treatment related lesion was detected in the forestomach of both sexes at 2.0 m g/kg. These lesions were characterized by necrosis of the stratified squamous epithelium accompanied by infiltration of neutrophils and macrophages, proliferation of neocapillaries, hemorrhage, edema, and fibroblast proliferation. Mild acute inflammation of the glandular stomach was also observed in some cases at 1.0 and 2.0 mg/kg....
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Developmental Toxicity (Dominant Lethal Mutation) Study on Agent Lewisite. Dominant Lethal Study of Lewisite in Male Rats.
1993Co-Authors: Thomas J. Bucci, J C Dacre, Robert M. Parker, Kevin H. DennyAbstract:Abstract : Lewisite (dichloro(2-chlorovinyl)arsine, Agent L) was investigated as part of the US Army Toxicological Program on Chemical Agents. The study was conducted during January - April, 1990. Dosing was performed during 3-12 January, 1990. Twenty male CD rats per dose group were given 1.5, 0.75 or 0.375 mg/kg Lewisite or vehicle control (one ml sesame seed oil) daily by gavage for 5 days. Positive control males were given one ml sesame seed oil by gavage on Day 1-4 and on Day 5 they were given an intraperitoneal injection of 100 mg/kg ethyl methanesulphonate, a known mutagen. Each male was mated to two virgin females (12 weeks of age) per counted and the uteri and contents were examined. Implantation sites were categorized as live/dead fetuses or early/late resorption. No significant differences inreproductive indices were seen between treatment groups and the control group with the exception of the positive control. Males were killed during Week 13 and necropsied. Sperm morphology/modify, testicular histopathologic evaluation and morphometric analysis of seminiferous tubule cross-sections revealed no differences among Lewisite-treated rats and rats given sesame seed oil. There was no indication of a dominant lethal mutagenic or other toxic effect on the male reproductive tract as a result of exposure to Lewisite, under the conditions of this study. The No Observable Adverse Effect Level was the highest dose used, 1.500 mg/kg.
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Developmental toxicity (dominant lethal mutation) study on agent Lewisite. Dominant lethal study of Lewisite in male rats. Final report, 15 September 1988-14 June 1990
1993Co-Authors: Thomas J. Bucci, J C Dacre, Robert M. Parker, Kevin H. DennyAbstract:Lewisite (dichloro(2-chlorovinyl)arsine, Agent L) was investigated as part of the US Army Toxicological Program on Chemical Agents. The study was conducted during January - April, 1990. Dosing was performed during 3-12 January, 1990. Twenty male CD rats per dose group were given 1.5, 0.75 or 0.375 mg/kg Lewisite or vehicle control (one ml sesame seed oil) daily by gavage for 5 days. Positive control males were given one ml sesame seed oil by gavage on Day 1-4 and on Day 5 they were given an intraperitoneal injection of 100 mg/kg ethyl methanesulphonate, a known mutagen. Each male was mated to two virgin females (12 weeks of age) per counted and the uteri and contents were examined. Implantation sites were categorized as live/dead fetuses or early/late resorption. No significant differences inreproductive indices were seen between treatment groups and the control group with the exception of the positive control. Males were killed during Week 13 and necropsied. Sperm morphology/modify, testicular histopathologic evaluation and morphometric analysis of seminiferous tubule cross-sections revealed no differences among Lewisite-treated rats and rats given sesame seed oil. There was no indication of a dominant lethal mutagenic or other toxic effect on the male reproductive tract as a resultmore » of exposure to Lewisite, under the conditions of this study. The No Observable Adverse Effect Level was the highest dose used, 1.500 mg/kg.« less
C H Ho - One of the best experts on this subject based on the ideXlab platform.
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determination of Lewisite oxide in soil using solid phase microextraction followed by gas chromatography with flame photometric or mass spectrometric detection
Journal of Chromatography A, 2001Co-Authors: Bruce A Tomkins, Gary A Sega, C H HoAbstract:Abstract A rapid, sensitive, and convenient method is described for determining Lewisite oxide in soil. Samples are initially fortified with phenylarsine oxide (surrogate), then both species are extracted using ascorbic acid solutions containing 1,3-propanedithiol (derivatizing reagent). The corresponding filtered supernatant is sampled using a solid-phase microextraction fiber. Collected analytes are thermally desorbed in a heated gas chromatographic inlet, separated using fused-silica capillary columns (“primary” and “confirmatory”), and detected with either a mass spectrometric (selected ion monitoring mode) or flame photometric (sulfur-selective mode) detector. Two independent statistically-unbiased procedures were used to evaluate the detection limit for Lewisite oxide; the values range between 0.1 and 0.5 μg g−1 soil.
L B Sasser - One of the best experts on this subject based on the ideXlab platform.
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two generation reproduction study of Lewisite in rats
Journal of Applied Toxicology, 1999Co-Authors: L B Sasser, J A Cushing, C W Lindenmeier, P W Mellick, J C DacreAbstract:Lewisite, a potent toxic vesicant and chemical warfare agent, is used in a number of research laboratories, is stored in large quantities at depot sites throughout the USA and is occasionally transported to distant sites. Thus, the potential for environmental or occupational exposure exists where Lewisite is present. A 42-week two-generation study was conducted to determine the reproductive consequences of Lewisite in parental male and female rats and their offspring. Rats were administered Lewisite in sesame oil (0, 0.10, 0.25 or 0.60 mg kg -1 day -1 for 5 days a week) via intragastic intubation before mating, during mating and after mating until the birth of their offspring. The dams continued to receive Lewisite during lactation. At weaning, male and female offspring of each group were selected to continue the study, receiving Lewisite during adolescence, mating and throughout gestation and lactation. Lewisite had no adverse effect on reproduction performance, fertility or reproductive organ weights of male or female rats through two consecutive generations. No adverse effects to offspring were attributed to Lewisite exposure. Minor changes in growth were the only maternal effects observed. Lewisite exposure of parental rats caused no gross or microscopic lesion in testes, epididymis, prostate, seminal vesicles, ovaries, uterus or vagina. The no-observable-effect level (NOEL) for the reproductive effects of Lewisite would be >0.60 mg kg -1 day -1 .
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subchronic toxicity evaluation of Lewisite in rats
Journal of Toxicology and Environmental Health, 1996Co-Authors: L B Sasser, J A Cushing, P W Mellick, D. R. Kalkwarf, J C DacreAbstract:Health and exposure criteria have not been established for Lewisite [dichloro(2-chlorovinyl) arsine], a potent toxic vesicant that reacts with the sulfhydryl groups of proteins through its arsenic group. Sixty Sprague-Dawley rats of each sex, 6-7 wk old, were divided into 6 groups (10/group/sex) and gavaged with either 0, 0.01, 0.1, 0.5, 1.0, or 2.0 m g/kg of Lewisite in sesame oil 5 d/wk for 13 wk. No significant dose-related change in body weight was observed. At the high dose, serum protein, creatinine, SGOT, and SGPT were decreased in males; lymphocytes and platelets were increased in females. A treatment related lesion was detected in the forestomach of both sexes at 2.0 m g/kg. These lesions were characterized by necrosis of the stratified squamous epithelium accompanied by infiltration of neutrophils and macrophages, proliferation of neocapillaries, hemorrhage, edema, and fibroblast proliferation. Mild acute inflammation of the glandular stomach was also observed in some cases at 1.0 and 2.0 mg/kg....