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Kola M. Rao - One of the best experts on this subject based on the ideXlab platform.
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mutagenicity evaluation of Riot Control Agent o chlorobenzylidene malononitrile cs in the ames salmonella microsome test
Journal of Applied Toxicology, 1992Co-Authors: Ghansham P. Meshram, Padma R Malini, Kola M. RaoAbstract:o-Chlorobenzylidene malononitrile (CS), a Riot Control Agent, was evaluated for its possible mutagenic activity in the Ames Salmonella/mammalian microsome mutagenicity test. Five histidine-deficient (His−) mutant tester strains of Salmonella typhimurium—TA97a, TA98, TA100, TA102 and TA104—were used. The liquid preincubation procedure was used with metabolic activation (presence of S9 mixture) and without metabolic activation (absence of S9 mixture). For the experiments with metabolic activation, three different concentrations of S9 fraction (supernatant of Aroclor 1254-induced rat liver homogenate at 9000 g)—5%, 15% and 30% in S9 mixture—were used. Along with mutagenic activity, CS was also evaluated for cytotoxic activity in all the five tester strains of Salmonella typhimurium, both in the presence and absence of S9 mixture. The mutagenic and cytotoxic activities of CS were assessed by counting the His+ revertant colonies and by counting the microcolonies (His−, auxotrophs in the background lawn), respectively, and the respective mean values were compared with the relative negative (solvent) Control. A dose range of 12.5–800 μg plate−1 for CS did not induce a mutagenic response either in the presence or absence of S9 mix. No change in the negative mutagenic response of CS has been observed even in the presence of an elevated level of S9 fraction in the S9 mix. A dose of 200 μg plate−1 for CS was found to be cytotoxic by decreasing the surviving cells as well as His+ revertant colonies; however, the effect was reduced in the presence of an elevated level of S9 fraction in the S9 mix.
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Mutagenicity evaluation of Riot Control Agent o-chlorobenzylidene malononitrile (cs) in the ames salmonella/microsome test
Journal of applied toxicology : JAT, 1992Co-Authors: Ghansham P. Meshram, R. Padma Malini, Kola M. RaoAbstract:o-Chlorobenzylidene malononitrile (CS), a Riot Control Agent, was evaluated for its possible mutagenic activity in the Ames Salmonella/mammalian microsome mutagenicity test. Five histidine-deficient (His−) mutant tester strains of Salmonella typhimurium—TA97a, TA98, TA100, TA102 and TA104—were used. The liquid preincubation procedure was used with metabolic activation (presence of S9 mixture) and without metabolic activation (absence of S9 mixture). For the experiments with metabolic activation, three different concentrations of S9 fraction (supernatant of Aroclor 1254-induced rat liver homogenate at 9000 g)—5%, 15% and 30% in S9 mixture—were used. Along with mutagenic activity, CS was also evaluated for cytotoxic activity in all the five tester strains of Salmonella typhimurium, both in the presence and absence of S9 mixture. The mutagenic and cytotoxic activities of CS were assessed by counting the His+ revertant colonies and by counting the microcolonies (His−, auxotrophs in the background lawn), respectively, and the respective mean values were compared with the relative negative (solvent) Control. A dose range of 12.5–800 μg plate−1 for CS did not induce a mutagenic response either in the presence or absence of S9 mix. No change in the negative mutagenic response of CS has been observed even in the presence of an elevated level of S9 fraction in the S9 mix. A dose of 200 μg plate−1 for CS was found to be cytotoxic by decreasing the surviving cells as well as His+ revertant colonies; however, the effect was reduced in the presence of an elevated level of S9 fraction in the S9 mix.
Ghansham P. Meshram - One of the best experts on this subject based on the ideXlab platform.
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mutagenicity evaluation of Riot Control Agent o chlorobenzylidene malononitrile cs in the ames salmonella microsome test
Journal of Applied Toxicology, 1992Co-Authors: Ghansham P. Meshram, Padma R Malini, Kola M. RaoAbstract:o-Chlorobenzylidene malononitrile (CS), a Riot Control Agent, was evaluated for its possible mutagenic activity in the Ames Salmonella/mammalian microsome mutagenicity test. Five histidine-deficient (His−) mutant tester strains of Salmonella typhimurium—TA97a, TA98, TA100, TA102 and TA104—were used. The liquid preincubation procedure was used with metabolic activation (presence of S9 mixture) and without metabolic activation (absence of S9 mixture). For the experiments with metabolic activation, three different concentrations of S9 fraction (supernatant of Aroclor 1254-induced rat liver homogenate at 9000 g)—5%, 15% and 30% in S9 mixture—were used. Along with mutagenic activity, CS was also evaluated for cytotoxic activity in all the five tester strains of Salmonella typhimurium, both in the presence and absence of S9 mixture. The mutagenic and cytotoxic activities of CS were assessed by counting the His+ revertant colonies and by counting the microcolonies (His−, auxotrophs in the background lawn), respectively, and the respective mean values were compared with the relative negative (solvent) Control. A dose range of 12.5–800 μg plate−1 for CS did not induce a mutagenic response either in the presence or absence of S9 mix. No change in the negative mutagenic response of CS has been observed even in the presence of an elevated level of S9 fraction in the S9 mix. A dose of 200 μg plate−1 for CS was found to be cytotoxic by decreasing the surviving cells as well as His+ revertant colonies; however, the effect was reduced in the presence of an elevated level of S9 fraction in the S9 mix.
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Mutagenicity evaluation of Riot Control Agent o-chlorobenzylidene malononitrile (cs) in the ames salmonella/microsome test
Journal of applied toxicology : JAT, 1992Co-Authors: Ghansham P. Meshram, R. Padma Malini, Kola M. RaoAbstract:o-Chlorobenzylidene malononitrile (CS), a Riot Control Agent, was evaluated for its possible mutagenic activity in the Ames Salmonella/mammalian microsome mutagenicity test. Five histidine-deficient (His−) mutant tester strains of Salmonella typhimurium—TA97a, TA98, TA100, TA102 and TA104—were used. The liquid preincubation procedure was used with metabolic activation (presence of S9 mixture) and without metabolic activation (absence of S9 mixture). For the experiments with metabolic activation, three different concentrations of S9 fraction (supernatant of Aroclor 1254-induced rat liver homogenate at 9000 g)—5%, 15% and 30% in S9 mixture—were used. Along with mutagenic activity, CS was also evaluated for cytotoxic activity in all the five tester strains of Salmonella typhimurium, both in the presence and absence of S9 mixture. The mutagenic and cytotoxic activities of CS were assessed by counting the His+ revertant colonies and by counting the microcolonies (His−, auxotrophs in the background lawn), respectively, and the respective mean values were compared with the relative negative (solvent) Control. A dose range of 12.5–800 μg plate−1 for CS did not induce a mutagenic response either in the presence or absence of S9 mix. No change in the negative mutagenic response of CS has been observed even in the presence of an elevated level of S9 fraction in the S9 mix. A dose of 200 μg plate−1 for CS was found to be cytotoxic by decreasing the surviving cells as well as His+ revertant colonies; however, the effect was reduced in the presence of an elevated level of S9 fraction in the S9 mix.
Joseph J. Hout - One of the best experts on this subject based on the ideXlab platform.
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Association between exposure to o-chlorobenzylidene malononitrile (CS Riot Control Agent) and urinary metabolite 2-chlorohippuric acid in U.S. Army Mask Confidence Training
Journal of occupational and environmental hygiene, 2017Co-Authors: Maccon A. Buchanan, Joseph J. Hout, Alex Stubner, Mary T. Brueggemeyer, William BraggAbstract:ABSTRACTThis study was conducted among U.S. Army soldiers to evaluate the association between exposure to o-chlorobenzylidene malononitrile (CS Riot Control Agent) and urinary metabolite 2-chlorohippuric acid (CHA) detected in test subjects (n = 87) after completion of Mask Confidence Training. CS exposures ranged 0.086–4.9 mg/m³ ( = 2.7 mg/m³). CHA levels (corrected for creatinine) at 2-, 8-, 24-, and 30-hr post-exposure resulted in ranges of 94.6–1120 µg/g-cr ( = 389 µg/g-cr), 15.80–1170 µg/g-cr ( = 341 µg/g-cr), 4.00–53.1 µg/g-cr ( = 19.3 µg/g-cr), and 1.99–28.4 µg/g-cr ( = 10.6 µg/g-cr), respectively. Spearman's correlation revealed CHA levels strongly correlated with time sampled (r = −0.748, p < 0.05) and weakly correlated with CS concentration (r = 0.270, p < 0.05). A linear relationship was observed between CHA, CS concentration, and time of urine sample according to the following regression equation: ln(CHA, μg/g-cr) = 5.423 + 0.316 (CS conc., mg/m³) – 0.002 (time sampled), (R = 0.910, R² = 0.827...
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o chlorobenzylidene malononitrile cs Riot Control Agent associated acute respiratory illnesses in a u s army basic combat training cohort
Military Medicine, 2014Co-Authors: Joseph J. Hout, Duvel W. White, Anthony R Artino, Joseph J. KnapikAbstract:ABSTRACT Acute respiratory illnesses (ARIs) are among the leading causes for hospital visits in U.S. military training populations and historically peak during U.S. Army Basic Combat Training (BCT) following mandatory exposure to the Riot Control Agent o-chlorobenzylidene malononitrile (CS). This observational prospective cohort studied the association between CS exposures and ARI-related health outcomes in 6,723 U.S. Army recruits attending BCT at Fort Jackson, South Carolina from August 1 to September 25, 2012 by capturing and linking the incidence of ARI before and after the mask confidence chamber to CS exposure data. Recruits had a significantly higher risk (risk ratio = 2.44; 95% confidence interval = 1.74, 3.43) of being diagnosed with ARI following exposure to CS compared to the period of training preceding exposure, and incidence of ARI after CS exposure was dependent on the CS exposure concentration (p = 0.03). There was a significant pre-/postexposure ARI difference across all CS concentration ...
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O-Chlorobenzylidene Malononitrile (CS Riot Control Agent) Exposures and Associated Acute Respiratory Illnesses in a United States Army Basic Combat Training Cohort
2014Co-Authors: Joseph J. HoutAbstract:Abstract : Acute Respiratory Illnesses (ARIs) are among the leading causes for hospital visits and lost work time in United States (US) military training populations. The occurrence of ARIs in military recruit populations has been well studied, but understanding of casual factors is limited. Studies consistently demonstrate an increased ARI rate during week four through six of US Army Basic Combat Training (BCT), immediately following mandatory exposure to the Riot Control Agent o-chlorobenzylidene malononitrile (CS tear gas) during Mask Confidence Training (MCT). MCT is conducted during the first three weeks of BCT by thermally dispersing CS in a relatively air-tight structure where recruits wearing military issued M40 series protective masks enter, perform a series of exercises, remove their protective masks, and exit the structure. Recruits feel an intense burning sensation on exposed skin and, after removing the mask, almost immediate lacrimation, violent coughing spasms, and sometimes vomiting. Partly as a result of initial studies conducted for this dissertation, the US Army implemented All Army Activities Message (ALARACT) 051/2013 to decrease CS exposure concentrations and health effects associated with this training. Currently, no studies exist that quantify CS exposure concentrations in a US Army BCT population; furthermore, there are no studies that consider CS exposure as a potential risk factor for ARI diagnoses in this population.
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O-chlorobenzylidene malononitrile (CS Riot Control Agent) exposure in a U.S. Army basic combat training cohort.
Journal of environmental health, 2014Co-Authors: Joseph J. Hout, Duvel W. White, Alex Stubner, Michael E. Stevens, Joseph J. KnapikAbstract:All U.S. Army soldiers participate in mask confidence training during initial military training and periodically throughout their careers. Training is conducted by dispersing the Riot Control Agent, o-chlorobenzylidene malononitrile (CS), in a relatively air-tight structure where soldiers enter and conduct a series of exercises that culminate with mask removal. The study described here quantified CS concentrations experienced by 6,723 trainees and seven chamber operators during U.S. Army basic combat training at Fort Jackson, South Carolina, from August 1 to September 25, 2012. All 6,723 trainees were potentially exposed to CS concentrations exceeding the American Conference of Governmental Industrial Hygienists threshold limit value-ceiling (TLV-C) (0.39 mg/m3), 6,589 of which were potentially exposed to concentrations exceeding the value deemed immediately dangerous to life and health (IDLH) (2.0 mg/m3) by the National Institute for Occupational Safety and Health. All chamber operators were exposed to concentrations exceeding both the TLV-C and the IDLH.
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Identification of Compounds Formed During Low Temperature Thermal Dispersion of Encapsulated o-Chlorobenzylidene Malononitrile (CS Riot Control Agent)
Journal of occupational and environmental hygiene, 2010Co-Authors: Joseph J. Hout, Gary L. Hook, Peter T. Lapuma, Duvel W. WhiteAbstract:U.S. Army chemical mask confidence training is conducted in an enclosed chamber where airborne o-chlorobenzylidene malononitrile (also known as CS or “tear gas”) is generated using a low temperature (150–300°C) dispersal method. CS capsules are placed onto a flame-heated aerosol generator that melts the capsules and disperses CS into the chamber. To instill confidence in chemical protective equipment, trainees are required to break the seal of their chemical protective mask, resulting in the immediate irritation of their eyes, nose, throat, and lungs. Solid phase micro extraction (SPME) sample collection techniques were used inside the chamber, followed by gas chromatography and mass spectrometry (GC/MS) to identify unintended thermal degradation products created during the CS dispersal process. The temperature of the aerosol generator averaged 257°C, and 17 thermal degradation products were identified. To characterize the relationship between temperature and the types of CS thermal degradation products f...
R Vijayaraghavan - One of the best experts on this subject based on the ideXlab platform.
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Thermal decomposition studies of Riot Control Agent ω-chloroacetophenone (CN) by pyrolysis-gas chromatography-mass spectrometry.
Journal of hazardous materials, 2010Co-Authors: Anil K Nigam, M.v.s. Suryanarayana, P. K. Gutch, Shiv P Sharma, L N S Tomar, R VijayaraghavanAbstract:Pyrolysis-GC/MS system with on-line micro-furnace was used to make rapid evaluation of ω-chloroacetophenone (CN) decomposition under inert thermal atmospheres. The volatile products evolved during pyrolysis were analyzed by thermal gravimetric analysis (TGA) and Py-GC/MS to obtain specific thermogram and pyrogram. Thermal gravimetric analysis results showed that CN undergoes sublimation at 167°C prior to its decomposition at 229°C. Totally 45 degradation products were identified based on mass spectral library matching with the aid of correlation of the values of boiling point (bp) and retention time. A large number of mono-aromatics and polycyclic aromatic hydrocarbons were observed beyond 600°C. In addition to the aromatic hydrocarbons, oxygenated compounds were also observed during the pyrolysis process. The pyrolysis mechanism was proposed based on the determined pyrolysates and their relative abundance with temperature. The investigation results can provide significant information for understanding the thermal behavior of CN and evaluation of the potential influence of the pyrolysates to living being and the environment.
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Thermal decomposition studies of Riot Control Agent ω-chloroacetophenone (CN) by pyrolysis-gas chromatography–mass spectrometry
Journal of Hazardous Materials, 2010Co-Authors: Anil K Nigam, Pranav K. Gutch, M.v.s. Suryanarayana, Shiv P Sharma, L N S Tomar, R VijayaraghavanAbstract:Abstract Pyrolysis-GC/MS system with on-line micro-furnace was used to make rapid evaluation of ω-chloroacetophenone (CN) decomposition under inert thermal atmospheres. The volatile products evolved during pyrolysis were analyzed by thermal gravimetric analysis (TGA) and Py-GC/MS to obtain specific thermogram and pyrogram. Thermal gravimetric analysis results showed that CN undergoes sublimation at 167 °C prior to its decomposition at 229 °C. Totally 45 degradation products were identified based on mass spectral library matching with the aid of correlation of the values of boiling point (bp) and retention time. A large number of mono-aromatics and polycyclic aromatic hydrocarbons were observed beyond 600 °C. In addition to the aromatic hydrocarbons, oxygenated compounds were also observed during the pyrolysis process. The pyrolysis mechanism was proposed based on the determined pyrolysates and their relative abundance with temperature. The investigation results can provide significant information for understanding the thermal behavior of CN and evaluation of the potential influence of the pyrolysates to living being and the environment.
P. K. Gutch - One of the best experts on this subject based on the ideXlab platform.
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Thermal decomposition studies of Riot Control Agent ω-chloroacetophenone (CN) by pyrolysis-gas chromatography-mass spectrometry.
Journal of hazardous materials, 2010Co-Authors: Anil K Nigam, M.v.s. Suryanarayana, P. K. Gutch, Shiv P Sharma, L N S Tomar, R VijayaraghavanAbstract:Pyrolysis-GC/MS system with on-line micro-furnace was used to make rapid evaluation of ω-chloroacetophenone (CN) decomposition under inert thermal atmospheres. The volatile products evolved during pyrolysis were analyzed by thermal gravimetric analysis (TGA) and Py-GC/MS to obtain specific thermogram and pyrogram. Thermal gravimetric analysis results showed that CN undergoes sublimation at 167°C prior to its decomposition at 229°C. Totally 45 degradation products were identified based on mass spectral library matching with the aid of correlation of the values of boiling point (bp) and retention time. A large number of mono-aromatics and polycyclic aromatic hydrocarbons were observed beyond 600°C. In addition to the aromatic hydrocarbons, oxygenated compounds were also observed during the pyrolysis process. The pyrolysis mechanism was proposed based on the determined pyrolysates and their relative abundance with temperature. The investigation results can provide significant information for understanding the thermal behavior of CN and evaluation of the potential influence of the pyrolysates to living being and the environment.
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Chromatographic analysis of benzylidenemalononitrile analogues of 2-chlorobenzylidenemalononitrile
Journal of the Indian Chemical Society, 2004Co-Authors: P. K. Gutch, R. C. Malhotra, V. Dubey, R. S. Dangi, D. K. JaiswalAbstract:The Riot Control Agent 2-chorobenzylidenemalononitrile (CS) and its ortho and para substituted benzylidenemalononitrile (BMN) analogues were synthesised and characterized by spectroscopic techniques (IR, NMR and mass spectrometry). These compounds were also analysed using thin layer chromatography (TLC), high performance liquid chromatography (HPLC) and gas chromatography (GC). The chromatographic identification parameters such as retardation factor, capacity factor and retention indices were related to the hydrophobicity of synthesised BMN. Since hydrophobicity is an important determinant of the irritancy, the study thus provides a suitable measure for estimating the potential use of the derivatives of CS as tear gas compounds for Riot Control.
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Studies on thermal degradation of benzylidene malononitriles
Journal of Thermal Analysis and Calorimetry, 2003Co-Authors: P. K. Gutch, S. K. Raza, R. C. MalhotraAbstract:Thermal decomposition studies have been carried out using flash vacuum thermolysis (FVT) to find out the decomposition temperature for benzylidene malononitriles (BMNs) including 2-chlorobenzylidene malononitrile (cs), a widely used Riot Control Agent. The FVT studies have been carried out in a specially designed all glass assembly at various temperatures ranging from 300 to 600°C. A number of rearranged products along with hydrogen cyanide were obtained as major decomposition products. The products were analysed and the structures were confirmed by GC/MS. the thermal behaviour of BMNs has also been investigated by TG under nitrogen atmosphere. These studies show that the pyrotechnic mixture for tear gas munitions should not have burst temperature above 300°C.
