30 results on '"James C. Ball"'
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2. DUAL USE RESEARCH OF CONCERN: DERIVATIVES OF 3-QUINUCLIDINYL BENZILATE (BZ)
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James C. Ball
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Emergency Medical Services ,Chemical Warfare Agents ,Engineering ,3-Quinuclidinyl benzilate ,business.industry ,Veterinary (miscellaneous) ,Biosecurity ,Internet privacy ,Public Health, Environmental and Occupational Health ,Computer security ,computer.software_genre ,Quinuclidinyl Benzilate ,Dual (category theory) ,Immunology and Microbiology (miscellaneous) ,Drug development ,Emergency Medicine ,medicine ,business ,Pharmacology, Toxicology and Pharmaceutics (miscellaneous) ,computer ,medicine.drug ,Chemical weapon - Abstract
Summary Dual Use Research of Concern (DURC) deals with the unintended consequences of research and development and is particularly acute in the area of drug development. The United States National Science Advisory Board for Biosecurity (NSABB) has defined DURC as "research that, based on current understanding, can be reasonably anticipated to provide knowledge, products, or technologies that could be directly misapplied by others to pose a threat to public health, agriculture, plants, animals, the environment, or materiel” (1). One particular receptor antagonist and glycolate anticholinergic compound (BZ, QNB or 3 -quinuclidinyl benzilate) was stockpiled by the United States as a non-lethal chemical weapon that incapacitates and severely degrades the capability of exposed individuals (2). Given time and medical treatment, combatants and non-combatants exposed to such incapacitating agents could recover without any long-term effects. The purpose of this review is to identify potential new and more potent incapacitating agents based on the structures of BZ or atropine using peer reviewed publications of new pharmaceutical agents. A number of peer reviewed studies have reported on compounds with effects observed at lower concentrations than or comparable to BZ suggesting that these compounds could also be developed as potential chemical incapacitating chemical warfare agents and represent good examples of the principal of Dual Use Research of Concern.
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- 2015
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3. BINDING OF QUATERNARY AMMONIUM SALTS TO ACETYLCHOLINE RECEPTORS: POSSIBLE CHEMICAL WARFARE NERVE AGENTS
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James C. Ball
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Emergency Medical Services ,Chemistry ,Veterinary (miscellaneous) ,Public Health, Environmental and Occupational Health ,Combinatorial chemistry ,chemistry.chemical_compound ,Immunology and Microbiology (miscellaneous) ,Emergency Medicine ,medicine ,Ammonium ,Pharmacology, Toxicology and Pharmaceutics (miscellaneous) ,Acetylcholine receptor ,Nerve agent ,medicine.drug - Published
- 2013
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4. Atmospheric Chemistry of Perfluoroaldehydes (CxF2x+1CHO) and Fluorotelomer Aldehydes (CxF2x+1CH2CHO): Quantification of the Important Role of Photolysis
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Robert C. Buck, James C Ball, Robert L. Waterland, Fabio E Malanca, Malisa S. Chiappero, Steven T Wooldridge, Timothy J Wallington, Gustavo A Argüello, and Michael D Hurley
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Uv spectra ,Chemistry ,Atmospheric chemistry ,Yield (chemistry) ,Photodissociation ,Uv absorption ,Analytical chemistry ,Quantum yield ,Physical and Theoretical Chemistry ,Fluorotelomer - Abstract
The UV absorption spectra of CF(3)CHO, C(2)F(5)CHO, C(3)F(7)CHO, C(4)F(9)CHO, CF(3)CH(2)CHO, and C(6)F(13)CH(2)CHO were recorded over the range 225-400 nm at 249-297 K. C(x)F(2)(x)(+1)CHO and C(x)F(2)(x)(+1)CH(2)CHO have broad absorption features centered at 300-310 and 290-300 nm, respectively. The strength of the absorption increases with the size of the C(x)F(2)(x)(+1) group. There was no discernible (
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- 2006
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5. Atmospheric Chemistry of CF3CH2CH2OH: Kinetics, Mechanisms and Products of Cl Atom and OH Radical Initiated Oxidation in the Presence and Absence of NOX
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Michael D. Hurley, Jessica A. Misner, James C. Ball, Timothy J. Wallington, D. A. Ellis, J. W. Martin, S. A. Mabury, and M. P. Sulbaek Andersen
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Physical and Theoretical Chemistry - Abstract
Relative rate techniques were used to study the kinetics of the reactions of Cl atoms and OH radicals with CF(3)CH(2)C(O)H and CF(3)CH(2)CH(2)OH in 700 Torr of N(2) or air diluent at 296 +/- 2 K. The rate constants determined were k(Cl+CF(3)CH(2)C(O)H) = (1.81 +/- 0.27) x 10(-11), k(OH+CF(3)CH(2)C(O)H) = (2.57 +/- 0.44) x 10(-12), k(Cl+CF(3)CH(2)CH(2)OH) = (1.59 +/- 0.20) x 10(-11), and k(OH+CF(3)CH(2)CH(2)OH) = (6.91 +/- 0.91) x 10(-13) cm(3) molecule(-1) s(-1). Product studies of the chlorine initiated oxidation of CF(3)CH(2)CH(2)OH in the absence of NO show the sole primary product to be CF(3)CH(2)C(O)H. Product studies of the chlorine initiated oxidation of CF(3)CH(2)CH(2)OH in the presence of NO show the primary products to be CF(3)CH(2)C(O)H (81%), HC(O)OH (10%), and CF(3)C(O)H. Product studies of the chlorine initiated oxidation of CF(3)CH(2)C(O)H in the absence of NO show the primary products to be CF(3)C(O)H (76%), CF(3)CH(2)C(O)OH (14%), and CF(3)CH(2)C(O)OOH (or =10%). As part of this work, an upper limit of k(O(3)+CF(3)CH(2)CH(2)OH)2 x 10(-21) cm(3) molecule(-1) s(-1) was established. Results are discussed with respect to the atmospheric chemistry of fluorinated alcohols.
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- 2005
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6. Atmospheric Chemistry of 4:2 Fluorotelomer Alcohol (CF3(CF2)3CH2CH2OH): Products and Mechanism of Cl Atom Initiated Oxidation
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Timothy J. Wallington, Scott A. Mabury, Michael D. Hurley, James C. Ball, Jonathan W. Martin, David A. Ellis, and M. P. Sulbaek Andersen
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Fluorotelomer alcohol ,chemistry.chemical_compound ,chemistry ,Atmospheric chemistry ,Torr ,Atom ,Physical and Theoretical Chemistry ,Fourier transform infrared spectroscopy ,Photochemistry ,Smog chamber ,Diluent - Abstract
Smog chamber/FTIR techniques were used to study the products and mechanism of the Cl atom initiated oxidation of 4:2 fluorotelomer alcohol (CF3(CF2)3CH2CH2OH) in 700 Torr of N2/O2 diluent at 296 K....
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- 2004
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7. Atmospheric Chemistry of n-CxF2x+1CHO (x = 1, 3, 4): Reaction with Cl Atoms, OH Radicals and IR Spectra of CxF2x+1C(O)O2NO2
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Ole John Nielsen, Scott A. Mabury, Jonathan E. Stevens, M. P. Sulbaek Andersen, Michael D. Hurley, Timothy J. Wallington, James C. Ball, David A. Ellis, and Jonathan W. Martin
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Chemistry ,Computational chemistry ,Torr ,Atmospheric chemistry ,Radical ,Analytical chemistry ,Infrared spectroscopy ,Physical and Theoretical Chemistry ,Fourier transform infrared spectroscopy ,Smog chamber - Abstract
Smog chamber/FTIR techniques were used to measure (Cl + n-CxF2x+1CHO, x = 1, 3, 4) = (2.1 ± 0.5) × 10-12 and k(OH + n-CxF2x+1CHO, x = 1, 3, 4) = (6.5 ± 1.2) × 10-13 cm3 molecule-1 s-1 in 700 Torr o...
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- 2004
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8. The First Shed Skin of Neonate Corn Snakes Is Chemically Different from Adult Shed Skins
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James C. Ball
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integumentary system ,biology ,Botany ,food and beverages ,Animal Science and Zoology ,Food science ,Gas chromatography ,Elaphe ,biology.organism_classification ,Ecology, Evolution, Behavior and Systematics ,Saponification - Abstract
The first shed skins from the same clutch of neonate Corn Snakes (Elaphe gutatta gutatta) and the shed skin of conspecific adults were extracted sequentially with hexane, dichloromethane, and methanol. These solvents extracted more mass from neonate shed skins compared to adults. Gas chromatography of the hexane extract, after saponification of the lipids, showed that the percent of cholesterol was greater in shed skins from neonates, whereas many of the fatty acids were found in greater amounts from adults shed skins. These data show that the first shed skin of Corn Snakes is biochemically different from adults.
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- 2004
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9. Homogeneous Aerosol Formation by the Chlorine Atom Initiated Oxidation of Toluene
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Rune S. Karlsson, James C. Ball, Joseph J. Szente, and M. Matti Maricq
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Particle number ,Chemistry ,Inorganic chemistry ,Analytical chemistry ,chemistry.chemical_element ,Toluene ,Chemical reaction ,Aerosol ,chemistry.chemical_compound ,Volume (thermodynamics) ,Scanning mobility particle sizer ,Chlorine ,Particle ,Physical and Theoretical Chemistry - Abstract
The photolysis of Cl2 molecules in the presence of toluene and oxygen, at levels of ∼1014 radicals/cm-3, initiates a sequence of chemical reactions that rapidly produce an aerosol. Size distributions of the aerosol particles are examined, using a scanning mobility particle sizer, as a function of time, photolysis energy, the initial concentrations of toluene and chlorine, and of added NO and HO2. The number of particles and the volume of aerosol both exhibit a steep nonlinear increase as the initial chlorine atom level is raised. Surprisingly, the number of particles displays a strong inverse dependence on the initial toluene concentration, whereas the aerosol volume remains nearly unaffected by toluene level. Kinetic measurements of particle formation made using a flow reactor reveal an incubation period after initiation of the Cl + C6H5CH3 reaction, followed by steep increases in particle number and volume. The particle number rapidly reaches a plateau, whereas the aerosol volume continues to increase w...
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- 2000
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10. Atmospheric Chemistry of the Phenoxy Radical, C6H5O(•): UV Spectrum and Kinetics of Its Reaction with NO, NO2, and O2
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Ann Marie Straccia, J. Platz, Michael D. Hurley, William F. Schneider, Jens Sehested, Timothy J. Wallington, Ole John Nielsen, and James C. Ball
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chemistry.chemical_compound ,Reaction rate constant ,chemistry ,Atmospheric chemistry ,Radical ,Radiolysis ,Kinetics ,Analytical chemistry ,Phenol ,Physical and Theoretical Chemistry ,Mass spectrometry ,Photochemistry ,NOx - Abstract
Pulse radiolysis and FT-IR smog chamber experiments were used to investigate the atmospheric fate of C6H5O(•) radicals. Pulse radiolysis experiments gave σ(C6H5O(•))235 nm = (3.82 ± 0.48) × 10-17 cm2 molecule-1, k(C6H5O(•) + NO) = (1.88 ± 0.16) × 10-12, and k(C6H5O(•) + NO2) = (2.08 ± 0.15) × 10-12 cm3 molecule-1 s-1 at 296 K in 1000 mbar of SF6 diluent. No discernible reaction of C6H5O(•) radicals with O2 was observed in smog chamber experiments, and we derive an upper limit of k(C6H5O(•) + O2) < 5 × 10-21 cm3 molecule-1 s-1 at 296 K. These results imply that the atmospheric fate of phenoxy radicals in urban air masses is reaction with NOx. Density functional calculations and gas chromatography−mass spectrometry are used to identify 4-phenoxyphenol as the major product of the self-reaction of C6H5O(•) radicals. As part of this study, relative rate techniques were used to measure rate constants for reaction of Cl atoms with phenol [k(Cl + C6H5OH) = (1.93 ± 0.36) × 10-10], several chlorophenols [k(Cl + 2-c...
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- 1998
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11. FTIR Product Study of the Reactions CH3O2 + CH3O2 and CH3O2 + O3
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Timothy J. Wallington, James C. Ball, and Geoffrey S. Tyndall
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Ozone ,Chemistry ,Branching fraction ,Radical ,Photodissociation ,medicine.disease_cause ,Photochemistry ,Troposphere ,chemistry.chemical_compound ,Yield (chemistry) ,medicine ,Physical and Theoretical Chemistry ,Fourier transform infrared spectroscopy ,Ultraviolet - Abstract
The products of the self-reaction of methylperoxy radicals have been determined at 296 K in a 140-L chamber using continuous ultraviolet photolysis with FTIR detection. The branching fraction for the reaction channel giving methoxy radicals is found to be (41 ± 4)%, in good agreement with two earlier studies but somewhat higher than the most recent investigations. No evidence was found for the production of CH3OOCH3 (yield
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- 1998
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12. Trifluoroacetic acid in ancient freshwater
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Timothy J. Wallington, Ole John Nielsen, Brian F. Scott, James C. Ball, and Christine Spencer
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Atmospheric Science ,chemistry.chemical_compound ,chemistry ,Environmental protection ,Environmental chemistry ,Trifluoroacetic acid ,General Environmental Science - Abstract
Substantial concentrations (typically 10–100 ng/l) of trifluoroacetic acid (TFA) have been reported in contemporary saltwater and freshwater. It is well established that TFA is produced as the result of industrial activities. It is unclear whether there are any significant natural sources of this compound. To provide insight into the likely magnitude of possible natural sources of TFA we collected five samples of pre-industrial (>2000 year old) freshwater from Greenland and Denmark; there was no detectable TFA (
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- 2001
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13. Comparison of plate counts, Petrifilm, dipslides, and adenosine triphosphate bioluminescence for monitoring bacteria in cooling-tower waters
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Byung R. Kim, James E. Anderson, James C. Ball, and Sherry A. Mueller
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Microbiological culture ,food.ingredient ,Luminescence ,Colony Count, Microbial ,Petrifilm ,Incubation period ,Microbiology ,chemistry.chemical_compound ,food ,Adenosine Triphosphate ,Environmental Chemistry ,Yeast extract ,Agar ,Food science ,Waste Management and Disposal ,Water Science and Technology ,biology ,Bacteria ,Ecological Modeling ,Liter ,biology.organism_classification ,Pollution ,chemistry ,Water Microbiology ,Nutrient agar - Abstract
Effective bacterial control in cooling-tower systems requires accurate and timely methods to count bacteria. Plate-count methods are difficult to implement on-site, because they are time- and labor-intensive and require sterile techniques. Several field-applicable methods (dipslides, Petrifilm, and adenosine triphosphate [ATP] bioluminescence) were compared with the plate count for two sample matrices--phosphate-buffered saline solution containing a pure culture of Pseudomonas fluorescens and cooling-tower water containing an undefined mixed bacterial culture. For the pure culture, (1) counts determined on nutrient agar and plate-count agar (PCA) media and expressed as colony-forming units (CFU) per milliliter were equivalent to those on R2A medium (p = 1.0 and p = 1.0, respectively); (2) Petrifilm counts were not significantly different from R2A plate counts (p = 0.99); (3) the dipslide counts were up to 2 log units higher than R2A plate counts, but this discrepancy was not statistically significant (p = 0.06); and (4) a discernable correlation (r2 = 0.67) existed between ATP readings and plate counts. For cooling-tower water samples (n = 62), (1) bacterial counts using R2A medium were higher (but not significant; p = 0.63) than nutrient agar and significantly higher than tryptone-glucose yeast extract (TGE; p = 0.03) and PCA (p < 0.001); (2) Petrifilm counts were significantly lower than nutrient agar or R2A (p = 0.02 and p < 0.001, respectively), but not statistically different from TGE, PCA, and dipslides (p = 0.55, p = 0.69, and p = 0.91, respectively); (3) the dipslide method yielded bacteria counts 1 to 3 log units lower than nutrient agar and R2A (p < 0.001), but was not significantly different from Petrifilm (p = 0.91), PCA (p = 1.00) or TGE (p = 0.07); (4) the differences between dipslides and the other methods became greater with a 6-day incubation time; and (5) the correlation between ATP readings and plate counts varied from system to system, was poor (r2 values ranged from < 0.01 to 0.47), and the ATP method was not sufficiently sensitive to measure counts below approximately 10(4) CFU/mL.
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- 2009
14. Fourier transform infrared studies of the reaction of Cl atoms with PAN, PPN, CH3OOH, HCOOH, CH3COCH3 and CH3COC2H5 at 295�2 K
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Steven M. Japar, Timothy J. Wallington, Jean M. Andino, and James C. Ball
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chemistry.chemical_classification ,Atmospheric Science ,Chemistry ,Formic acid ,Chloromethane ,Butanone ,Analytical chemistry ,Chloroethane ,Chemical reaction ,Methane ,chemistry.chemical_compound ,Hydrocarbon ,Reaction rate constant ,Environmental Chemistry ,Organic chemistry - Abstract
The relative rate technique has been used to measure rate constants for the reaction of chlorine atoms with peroxyacetylnitrate (PAN), peroxypropionylnitrate (PPN), methylhydroperoxide, formic acid, acetone and butanone. Decay rates of these organic species were measured relative to one or more of the following reference compounds; ethene, ethane, chloroethane, chloromethane, and methane. Using rate constants of 9.29×10−11, 5.7×10−11, 8.04×10−12, 4.9×10−13, and 1.0×10−13 cm3 molecule−1 sec−1 for the reaction of Cl atoms with ethene, ethane, chloroethane, chloromethane, and methane respectively, the following rate constants were derived, in units of cm3 molecule−1 s−1: PAN
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- 1990
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15. Atmospheric chemistry of the Z and E isomers of CF3CF=CHF; kinetics, mechanisms, and products of gas-phase reactions with Cl atoms, OH radicals, and O3
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James C. Ball, Michael D. Hurley, and Timothy J. Wallington
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Reaction rate constant ,Chemistry ,Radical ,Atmospheric chemistry ,Kinetics ,Physical chemistry ,Physical and Theoretical Chemistry ,Fourier transform infrared spectroscopy ,Smog chamber ,Gas phase - Abstract
Smog chamber/FTIR techniques were used to study the atmospheric chemistry of the Z and E isomers of CF3CF=CHF, which we refer to as CF3CF=CHF(Z) and CF3CF=CHF(E). The rate constants k(Cl + CF3CF=CHF(Z)) = (4.36 +/- 0.48) x 10-11, k(OH + CF3CF=CHF(Z)) = (1.22 +/- 0.14) x 10-12, and k(O3 + CF3CF=CHF(Z)) = (1.45 +/- 0.15) x 10-21 cm3 molecule-1 s-1 were determined for the Z isomer of CF3CF=CHF in 700 Torr air diluent at 296 +/- 2 K. The rate constants k(Cl + CF3CF=CHF(E)) = (5.00 +/- 0.56) x 10-11, k(OH + CF3CF=CHF(E)) = (2.15 +/- 0.23) x 10-12, and k(O3 + CF3CF=CHF(E)) = (1.98 +/- 0.15) x 10-20 cm3 molecule-1 s-1 were determined for the E isomer of CF3CF=CHF in 700 Torr air diluent at 296 +/- 2 K. Both the Cl-atom and OH-radical-initiated atmospheric oxidation of CF3CF=CHF give CF3C(O)F and HC(O)F in molar yields indistinguishable from 100% for both the Z and E isomer. CF3CF=CHF(Z) has an atmospheric lifetime of approximately 18 days and a global warming potential (100 year time horizon) of approximately 6. CF3CF=CHF(E) has an atmospheric lifetime of approximately 10 days and a global warming potential (100 year time horizon) of approximately 3. CF3CF=CHF has a negligible global warming potential and will not make any significant contribution to radiative forcing of climate change.
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- 2007
16. Atmospheric chemistry of a model biodiesel fuel, CH3C(O)O(CH2)2OC(O)CH3: kinetics, mechanisms, and products of Cl atom and OH radical initiated oxidation in the presence and absence of NOx
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S. Bertman, A. Toft, Ole John Nielsen, M. Perkovic, Michael D. Hurley, Timothy J. Wallington, and James C. Ball
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Free Radicals ,Molecular Structure ,Spectrophotometry, Infrared ,Chemistry ,Atmosphere ,Radical ,Kinetics ,Analytical chemistry ,Diluent ,Medicinal chemistry ,chemistry.chemical_compound ,Reaction rate constant ,Models, Chemical ,Torr ,Atom ,Hydroxides ,Ethylene Glycols ,Nitrogen Oxides ,Physical and Theoretical Chemistry ,Chlorine ,Ethylene glycol ,Oxidation-Reduction ,NOx ,Gasoline - Abstract
Relative rate techniques were used to study the kinetics of the reactions of Cl atoms and OH radicals with ethylene glycol diacetate, CH3C(O)O(CH2)2OC(O)CH3, in 700 Torr of N2/O2 diluent at 296 K. The rate constants measured were k(Cl + CH3C(O)O(CH2)2OC(O)CH3) = (5.7 +/- 1.1) x 10(-12) and k(OH + CH3C(O)O(CH2)2OC(O)CH3) = (2.36 +/- 0.34) x 10(-12) cm3 molecule-1 s-1. Product studies of the Cl atom initiated oxidation of ethylene glycol diacetate in the absence of NO in 700 Torr of O2/N2 diluent at 296 K show the primary products to be CH3C(O)OC(O)CH2OC(O)CH3, CH3C(O)OC(O)H, and CH3C(O)OH. Product studies of the Cl atom initiated oxidation of ethylene glycol diacetate in the presence of NO in 700 Torr of O2/N2 diluent at 296 K show the primary products to be CH3C(O)OC(O)H and CH3C(O)OH. The CH3C(O)OCH2O* radical is formed during the Cl atom initiated oxidation of ethylene glycol diacetate, and two loss mechanisms were identified: reaction with O2 to give CH3C(O)OC(O)H and alpha-ester rearrangement to give CH3C(O)OH and HC(O) radicals. The reaction of CH3C(O)OCH2O2* with NO gives chemically activated CH3C(O)OCH2O* radicals which are more likely to undergo decomposition via the alpha-ester rearrangement than CH3C(O)OCH2O* radicals produced in the peroxy radical self-reaction.
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- 2007
17. Atmospheric chemistry of n-C(x)F(2)(x)(+1)CHO (x = 1, 2, 3, 4): fate of n-C(x)F(2)(x)(+1)C(O) radicals
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Ole John Nielsen, Scott A. Mabury, Michael D. Hurley, Timothy J. Wallington, Jonathan W. Martin, James C. Ball, David A. Ellis, and M. P. Sulbaek Andersen
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Air Pollutants ,Aldehydes ,Fluorocarbons ,Free Radicals ,Stereochemistry ,Chemistry ,Atmosphere ,Radical ,Analytical chemistry ,Carboxylic Acids ,Smog chamber ,Decomposition ,Peroxides ,Reaction rate constant ,Atmospheric chemistry ,Molecule ,Physical and Theoretical Chemistry - Abstract
Smog chamber/FTIR techniques were used to study the atmospheric fate of n-C(x)F(2)(x)(+1)C(O) (x = 1, 2, 3, 4) radicals in 700 Torr O(2)/N(2) diluent at 298 +/- 3 K. A competition is observed between reaction with O(2) to form n-C(x)()F(2)(x)()(+1)C(O)O(2) radicals and decomposition to form n-C(x)F(2)(x)(+1) radicals and CO. In 700 Torr O(2)/N(2) diluent at 298 +/- 3 K, the rate constant ratio, k(n-C(x)F(2)(x)(+1)C(O) + O(2) --> n-C(x)F(2)(x)(+1)C(O)O(2))/k(n-C(x)F(2)(x)(+1)C(O) --> n-C(x)F(2)(x)(+1) + CO) = (1.30 +/- 0.05) x 10(-17), (1.90 +/- 0.17) x 10(-19), (5.04 +/- 0.40) x 10(-20), and (2.67 +/- 0.42) x 10(-20) cm(3) molecule(-1) for x = 1, 2, 3, 4, respectively. In one atmosphere of air at 298 K, reaction with O(2) accounts for 99%, 50%, 21%, and 12% of the loss of n-C(x)F(2)(x)(+1)C(O) radicals for x = 1, 2, 3, 4, respectively. Results are discussed with respect to the atmospheric chemistry of n-C(x)F(2)(x)(+1)C(O) radicals and their possible role in contributing to the formation of perfluorocarboxylic acids in the environment.
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- 2006
18. Atmospheric chemistry of perfluoroaldehydes (CxF2x+1CHO) and fluorotelomer aldehydes (CxF2x+1CH2CHO): quantification of the important role of photolysis
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Malisa S, Chiappero, Fabio E, Malanca, Gustavo A, Argüello, Steven T, Wooldridge, Michael D, Hurley, James C, Ball, Timothy J, Wallington, Robert L, Waterland, and Robert C, Buck
- Abstract
The UV absorption spectra of CF(3)CHO, C(2)F(5)CHO, C(3)F(7)CHO, C(4)F(9)CHO, CF(3)CH(2)CHO, and C(6)F(13)CH(2)CHO were recorded over the range 225-400 nm at 249-297 K. C(x)F(2)(x)(+1)CHO and C(x)F(2)(x)(+1)CH(2)CHO have broad absorption features centered at 300-310 and 290-300 nm, respectively. The strength of the absorption increases with the size of the C(x)F(2)(x)(+1) group. There was no discernible (5%) effect of temperature on the UV spectra. Quantum yields for photolysis at 254 and 308 nm were measured. Quantum yields at 254 nm were 0.79 +/- 0.09 (CF(3)CHO), 0.81 +/- 0.09 (C(2)F(5)CHO), 0.63 +/- 0.09 (C(3)F(7)CHO), 0.60 +/- 0.09 (C(4)F(9)CHO), 0.74 +/- 0.08 (CF(3)CH(2)CHO), and 0.55 +/- 0.09 (C(6)F(13)CH(2)CHO). Quantum yields at 308 nm were 0.17 +/- 0.03 (CF(3)CHO), 0.08 +/- 0.02 (C(4)F(9)CHO), and 0.04 +/- 0.01 (CF(3)CH(2)CHO). The quantum yields decrease with increasing size of the C(x)F(2)(x)(+1) group and with increasing wavelength of the photolysis light. The photolysis quantum yield at 308 nm for CF(3)CHO measured here is a factor of at least 8 greater than that reported previously. Photolysis is probably the dominant atmospheric fate of C(x)F(2)(x)(+1)CHO (x = 1-4) and is an important fate of C(x)F(2)(x)(+1)CH(2)CHO (x = 1 and 6). These results have important ramifications concerning the yield of perfluorocarboxylic acids in the atmospheric oxidation of fluorotelomer alcohols.
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- 2006
19. Atmospheric chemistry of 4:2 fluorotelomer alcohol (n-C4F9CH2CH2OH): products and mechanism of Cl atom initiated oxidation in the presence of NOx
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David A. Ellis, Jonathan W. Martin, Scott A. Mabury, Michael D. Hurley, James C. Ball, Timothy J. Wallington, M. P. Sulbaek Andersen, and Ole John Nielsen
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chemistry.chemical_classification ,Fluorotelomer alcohol ,Chemistry ,Stereochemistry ,Radical ,Medicinal chemistry ,Decomposition ,chemistry.chemical_compound ,Atmospheric chemistry ,Yield (chemistry) ,Alkoxy group ,Physical and Theoretical Chemistry ,NOx ,Alkyl - Abstract
Smog chamber/FTIR techniques were used to study the Cl atom initiated oxidation of 4:2 fluorotelomer alcohol (C(4)F(9)CH(2)CH(2)OH, 4:2 FTOH) in the presence of NO(x) in 700 Torr of N(2)/O(2) diluent at 296 K. Chemical activation effects play an important role in the atmospheric chemistry of the peroxy, and possibly the alkoxy, radicals derived from 4:2 FTOH. Cl atoms react with C(4)F(9)CH(2)CH(2)OH to give C(4)F(9)CH(2)C(*)HOH radicals which add O(2) to give chemically activated alpha-hydroxyperoxy radicals, [C(4)F(9)CH(2)C(OO(*))HOH]*. In 700 Torr of N(2)/O(2) at 296 K, approximately 50% of the [C(4)F(9)CH(2)C(OO(*))HOH]* radicals decompose "promptly" to give HO(2) radicals and C(4)F(9)CH(2)CHO, the remaining [C(4)F(9)CH(2)C(OO(*))HOH]* radicals undergo collisional deactivation to give thermalized peroxy radicals, C(4)F(9)CH(2)C(OO(*))HOH. Decomposition to HO(2) and C(4)F(9)CH(2)CHO is the dominant atmospheric fate of the thermalized peroxy radicals. In the presence of excess NO, the thermalized peroxy radicals react to give C(4)F(9)CH(2)C(O(*))HOH radicals which then decompose at a rate >2.5 x 10(6) s(-1) to give HC(O)OH and the alkyl radical C(4)F(9)CH(2)(*). The primary products of 4:2 FTOH oxidation in the presence of excess NO(x) are C(4)F(9)CH(2)CHO, C(4)F(9)CHO, and HCOOH. Secondary products include C(4)F(9)CH(2)C(O)O(2)NO(2), C(4)F(9)C(O)O(2)NO(2), and COF(2). In contrast to experiments conducted in the absence of NO(x), there was no evidence (
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- 2006
20. Atmospheric chemistry of propionaldehyde: kinetics and mechanisms of reactions with OH radicals and Cl atoms, UV spectrum, and self-reaction kinetics of CH3CH2C(O)O2 radicals at 298 K
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Eric Villenave, Michael D. Hurley, Jean-Paul Le Crâne, James C. Ball, and Timothy J. Wallington
- Subjects
Chemical kinetics ,chemistry.chemical_compound ,Reaction rate constant ,chemistry ,Computational chemistry ,Radical ,Kinetics ,Photodissociation ,Molecule ,Flash photolysis ,Physical chemistry ,Propionaldehyde ,Physical and Theoretical Chemistry - Abstract
The kinetics and mechanism of the reactions of Cl atoms and OH radicals with CH3CH2CHO were investigated at room temperature using two complementary techniques: flash photolysis/UV absorption and continuous photolysis/FTIR smog chamber. Reaction with Cl atoms proceeds predominantly by abstraction of the aldehydic hydrogen atom to form acyl radicals. FTIR measurements indicated that the acyl forming channel accounts for (88 +/- 5)%, while UV measurements indicated that the acyl forming channel accounts for (88 +/- 3)%. Relative rate methods were used to measure: k(Cl + CH3CH2CHO) = (1.20 +/- 0.23) x 10(-10); k(OH + CH3CH2CHO) = (1.82 +/- 0.23) x 10(-11); and k(Cl + CH3CH2C(O)Cl) = (1.64 +/- 0.22) x 10(-12) cm3 molecule(-1) s(-1). The UV spectrum of CH3CH2C(O)O2, rate constant for self-reaction, and rate constant for cross-reaction with CH3CH2O2 were determined: sigma(207 nm) = (6.71 +/- 0.19) x 10(-18) cm2 molecule(-1), k(CH3CH2C(O)O2 + CH3CH2C(O)O2) = (1.68 +/- 0.08) x 10(-11), and k(CH3CH2C(O)O2 + CH3CH2O2) = (1.20 +/- 0.06) x 10(-11) cm3 molecule(-1) s(-1), where quoted uncertainties only represent 2sigma statistical errors. The infrared spectrum of C2H5C(O)O2NO2 was recorded, and products of the Cl-initiated oxidation of CH3CH2CHO in the presence of O2 with, and without, NO(x) were identified. Results are discussed with respect to the atmospheric chemistry of propionaldehyde.
- Published
- 2005
21. Particle characteristics responsible for effects on human lung epithelial cells
- Author
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Ann E, Aust, James C, Ball, Autumn A, Hu, JoAnn S, Lighty, Kevin R, Smith, Ann M, Straccia, John M, Veranth, and Willie C, Young
- Subjects
Air Pollutants ,Oxidative Stress ,Metals ,Biological Availability ,Humans ,Epithelial Cells ,Lung ,Oxidation-Reduction ,Cells, Cultured - Abstract
Some recent epidemiologic investigations have shown an association between increased incidence of respiratory symptoms and exposure to low levels of particulate matter (PM*) less than 10 microm or less than 2.5 microm in aerodynamic diameter (PM10 and PM2.5, respectively). If particulates are causally involved with respiratory symptoms, it is important to understand which components may be responsible. However, increasing evidence suggests that transition metals present in particles, especially iron, generate reactive oxygen species (ROS) that may be involved in producing some of the observed respiratory symptoms. The hypothesis for this study is twofold: bioavailable transition metals from inhaled airborne particulates catalyze redox reactions in human lung epithelial cells, leading to oxidative stress and increased production of mediators of pulmonary inflammation: and the size, transition metal content, and mineral speciation of particulates affect their ability to cause these effects. This work focused on the relation between physical characteristics of particles (eg, size, bioavailable transition metal content, and mineral speciation) and their ability to generate hydroxyl radicals in cell-free systems and to cause oxidative stress, which results in the synthesis of mediators of pulmonary inflammation in cultured human lung epithelial cells. These relations were studied by comparing size-fractionated, chemically characterized coal fly ash (CFA) produced by combustion of three different coals to obtain milligram quantities of ash. One transition metal, iron, was studied specifically because it is by far the predominant transition metal in CFA. In addition, smaller quantities of particles from gasoline engines, diesel engines, and ambient air were studied. Phosphate buffer soluble fractions from particles from all sources were capable of generating ROS, as measured by production of malondialdehyde (MDA) from 2-deoxyribose. This activity was inhibited over 90% for all particles by the metal chelator N-[5-[3-[(5-aminopentyl)hydroxycarbamoyl]propionamidol-pentyl]-3-[[5-(N-hydroxyacetamido)pentyl]carbamoyl]propionohydroxamic acid (desferrioxamine B, or DF), strongly suggesting that transition metal(s), probably iron, were responsible. Particles from coal or gasoline combustion had greater ability to produce ROS than particles from diesel combustion. Iron was mobilized by citrate (at pH 7.5) from particles of all sources tested; gasoline combustion particles were the only particles not analyzed for iron mobilization because there were not enough particles for the iron mobilization assay. CFA particles were size-fractioned; the amount of iron mobilized by citrate was inversely related to the size of particles and also depended on the source of coal. Iron from the CFA particles was responsible for inducing the iron-storage protein ferritin in cultured human lung epithelial cells (A549 cells). The amount of iron mobilized by citrate was directly proportional to the amount of ferritin induced in the A549 cells. Iron from the CFA was also responsible for inducing the inflammatory mediator interleukin (IL) 8 in A549 cells. Iron existed in several species in the fly ash, but the bioavailable iron was associated with the glassy aluminosilicate fraction, which caused ferritin and IL-8 to be induced in the A549 cells. In crustal dust, another component of urban particulates, iron was associated with oxides and clay but not with aluminosilicates. The crustal dust contained almost no iron that could be mobilized by citrate. Iron could be mobilized from diesel combustion particulates, but at a much lower level than for all other combustion particles. Samples of ambient PM2.5 collected in Salt Lake City over 5-day periods during one month varied widely in the amount of iron that could be mobilized. If bioavailable transition metals (eg, iron) are related to the specific biological responses outlined here, then the potential exists to develop in vitro assays to determine whether particulates of unknown composition and origin can cause effects similar to those observed in this study.
- Published
- 2003
22. The formation of reactive oxygen species catalyzed by neutral, aqueous extracts of NIST ambient particulate matter and diesel engine particles
- Author
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Ann E. Aust, Ann Marie Straccia, James C. Ball, and Willie C. Young
- Subjects
Aqueous solution ,Diesel exhaust ,Vanadyl sulfate ,Inorganic chemistry ,chemistry.chemical_element ,Zinc ,Air Pollutants, Occupational ,Management, Monitoring, Policy and Law ,Particulates ,Ascorbic acid ,Catalysis ,Mass Spectrometry ,chemistry.chemical_compound ,Iron sulfate ,chemistry ,Environmental chemistry ,Malondialdehyde ,Sulfate ,Reactive Oxygen Species ,Waste Management and Disposal ,Vehicle Emissions - Abstract
It is important to characterize the chemical properties of particulate matter in order to understand how low doses, inhaled by a susceptible population, might cause human health effects. The formation of reactive oxygen species catalyzed by neutral, aqueous extracts of two ambient particulate samples, National Institute of Standards & Technology (NIST) Standard Reference Materials (SRM) 1648 and 1649, and two diesel particulate samples, NIST SRM 1650 and SRM 2975, were measured. The formation of reactive oxygen species was estimated by measuring the formation of malondialdehyde from 2-deoxyribose in the presence of ascorbic acid; H2O2 was not added to this assay. SRM 1649, ambient particulate matter collected from Washington, DC, generated the most malondialdehyde, while SRM 2975, diesel particulate matter collected from a forklift, yielded the least amount. Desferrioxamine inhibited the formation of malondialdehyde from the particulate samples providing additional data to support the observation that transition metals were involved in the generation of reactive oxygen species. Six transition metal sulfates (iron sulfate, copper sulfate, vanadyl sulfate, cobalt sulfate, nickel sulfate, and zinc sulfate) were assayed for their ability to generate reactive oxygen species under the same conditions used for the particulate samples in order to facilitate comparisons between particles and these transition metals. The concentration of transition metals was measured in aqueous extracts of these particulate samples using ion-coupled plasma mass spectrometry (ICP-MS) analysis. There was qualitative agreement between the concentrations of Fe, Cu, and V and the amount of malondialdehyde produced from extracts of these particulate samples. These data suggest that transition metals can be dissolved from particles in neutral, aqueous solutions and that these metals are capable of catalyzing the formation of reactive oxygen species.
- Published
- 2000
23. Recovery of Ames Assay Mutagenicity of a Polar Fraction of a Diesel Engine Paniculate Extract from Capillary Gas Chromatography
- Author
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Joel F. O. Richert, Trescott E. Jensen, Willie C. Young, and James C. Ball
- Subjects
Chromatography, Gas ,Chromatography ,Mutagenicity Tests ,Chemistry ,Exhaust gas ,Fraction (chemistry) ,In Vitro Techniques ,Particulates ,Diesel engine ,Capillary gas chromatography ,Rats ,Ames test ,Animals ,Polar ,Gas chromatography ,Fuel Oils ,Mutagens ,Vehicle Emissions - Published
- 1991
- Full Text
- View/download PDF
24. Formation of trifluoroacetic acid from the atmospheric degradation of hydrofluorocarbon 134a: a human health concern?
- Author
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Timothy J. Wallington and James C. Ball
- Subjects
Air Pollutants ,Hydrocarbons, Fluorinated ,Management, Monitoring, Policy and Law ,chemistry.chemical_compound ,Human health ,chemistry ,Environmental chemistry ,Trifluoroacetic acid ,Degradation (geology) ,Organic chemistry ,Humans ,Trifluoroacetic Acid ,Hydrofluorocarbon ,Waste Management and Disposal ,Chemical decomposition - Published
- 1993
25. Detection of oxidative mutagens in an urban air-particulate extract: a preliminary study
- Author
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Marion Hoyer, Gerald J. Keeler, and James C. Ball
- Subjects
DNA, Bacterial ,Salmonella typhimurium ,Air Pollutants ,Methylene Chloride ,Chromatography ,Chemistry ,Mutagenicity Tests ,fungi ,Air pollution ,food and beverages ,Mutagen ,Pilot Projects ,General Medicine ,Oxidative phosphorylation ,Particulates ,medicine.disease_cause ,Oxidants ,Chloride ,Bacterial strain ,Ambient air ,Ames test ,Toxicology ,medicine ,medicine.drug ,Mutagens - Abstract
The Ames assays strains TA98 and TA100 have been useful in characterizing complex mixtures from organic solvent extracts of particles from diesel-powered vehicles, ambient air, and other sources. In this paper we report preliminary experiments using TA102, a bacterial strain that detects compounds that can oxidize DNA, to characterize the mutagenicity of an ambient air sample collected in Ann Arbor, MI. Four sets of ambient air filters were collected in duplicate over a period of several days. The mutagenicities of methylene chloride extracts of these filters were compared using strains TA98, TA100 and TA102. The concentration-mutagenicity data for TA98 and TA100 were linear over the concentration range 0–200 μg extract/plate. The mutagenicity of the extracts using TA102 was much lower than the other two strains and was non-linear over the concentration range tested. These results suggest that it would be difficult to use TA102 to identify the oxidative mutagens present in an ambient air particulate extract.
- Published
- 1992
26. Ames assay mutagenicity and electronic structure calculations of bromomethylfluoranthenes, chloromethylfluoranthenes, and hydroxymethylfluoranthenes
- Author
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James C. Ball and Willie C. Young
- Subjects
Fluorenes ,Strain (chemistry) ,Molecular Structure ,Stereochemistry ,Chemistry ,Mutagenicity Tests ,Methanol ,Intercalation (chemistry) ,Mutagenesis ,MNDO ,General Medicine ,Carbocation ,Toxicology ,Standard enthalpy of formation ,Ames test ,Hydrocarbons, Brominated ,Acetone ,Hydrocarbons, Chlorinated ,Solvents ,Thermodynamics ,Reactivity (chemistry) ,Dimethyl Sulfoxide - Abstract
The mutagenicities of the five possible isomers of bromomethylfluoranthene, chloromethylfluoranthene, and hydroxymethylfluoranthene were determined in the Ames assay using strains TA100 and TA98 without the addition of rat-liver S9 tissue extract. The mutagenicities of the bromomethyl and chloromethylfluoranthenes ranged from 25 to 6000 rev./nmol. The most mutagenic compound was 8-chloromethylfluoranthene in strain TA98 (6000 rev./nmol). The reactivities of the bromomethylfluoranthenes and the chloromethylfluoranthenes were estimated from electronic structure calculations using the MNDO and the PM3 semi-empirical methods. The bromomethylfluoranthenes showed the smallest differences between the heats of formation of the carbocations and the heats of formation of the parent bromomethyl derivatives. Therefore, the bromomethylfluoranthenes were estimated to be the most reactive of the halomethylfluoranthenes studied. The compound that showed the largest change in heat of formation (the most stable halomethylfluoranthene) going from the halomethylfluoranthene to the carbocation was 2-chloromethylfluoranthene. However, neither the most reactive nor the most stable halomethylfluoranthenes were the most mutagenic in either strain of bacteria. These results are interpreted to suggest that the reactivity of the parent halomethylfluoranthene is not a critical factor in the mechanism by which these compounds are mutagenic, but some other factor, perhaps intercalation, must be a critical step in the mechanism of mutagenesis of these compounds.
- Published
- 1991
27. Atmospheric Chemistry of Propionaldehyde: Kinetics and Mechanisms of Reactions with OH Radicals and Cl Atoms, UV Spectrum, and Self-Reaction Kinetics of CH3CH2C(O)O2 Radicals at 298 K.
- Author
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Jean-Paul Le Crâne, Eric Villenave, Michael D. Hurley, Timothy J. Wallington, and James C. Ball
- Published
- 2005
- Full Text
- View/download PDF
28. Cytotoxicity and mutagenicity of aflatoxin dichloride in normal and repair deficient diploid human fibroblasts
- Author
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Deborah Richmond, Veronica M. Maher, James C. Ball, Eileen M. Mahoney, David H. Swenson, and J. Justin McCormick
- Subjects
Male ,Aflatoxin B1 ,Xeroderma pigmentosum ,DNA Repair ,Cell Survival ,Guanine ,DNA damage ,DNA repair ,Toxicology ,Cell Line ,chemistry.chemical_compound ,Aflatoxins ,Salmon ,DNA adduct ,medicine ,Animals ,Humans ,Chromatography, High Pressure Liquid ,Carcinogen ,Mutagenicity Tests ,Infant, Newborn ,DNA ,General Medicine ,Fibroblasts ,medicine.disease ,chemistry ,Biochemistry ,Cattle ,Nucleotide excision repair - Abstract
The cytotoxic and mutagenic effect of aflatoxin B1-dichloride (AFB1-Cl2), a direct-acting carcinogen which is a model for the proposed ultimate reactive metabolite of AFB1 (the 2,3-epoxide), was compared in normal, repair-proficient, diploid human fibroblasts and in complementation Group A xeroderma pigmentosum cells (XP12BE) which are virtually incapable of excision repair of DNA damage induced by ultraviolet radiation, the 7,8-diol-9,10-epoxide of benzo[a]pyrene, and several reactive aromatic amide derivatives. The XP cells were significantly more sensitive than normal to the cytotoxic and mutagenic effects of AFB1-Cl2, not only as a function of concentration administered but also of the number of AFB1-Cl2 residues initially bound to DNA. Cytotoxicity was determined from survival of colony-forming ability; resistance to 6-thioguanine was the genetic marker used for mutagenicity. We compared the rate of loss of AFB1-Cl2-DNA adducts from cells treated and held in the non-dividing state (confluent) over several days, as well as their ability to recover from the potentially mutagenic and/or cytotoxic effects of the agent. AFB1-Cl2 residues were lost from both strains of cells and both exhibited a gradual increase in survival. However, the rate of loss of adducts from the DNA in the normal cells was more rapid than in XP cells and they exhibited recovery from higher doses of AFB1-Cl2 than XP cells. The major primary DNA adduct formed in the human cells and in isolated DNA was a chemically unstable guanine derivative which could undergo a change in structure with time posttreatment to form a more stable secondary adduct. The cytotoxic effect of AFB1-Cl2 was highly correlated with the presence of either of these guanine adducts. Evidence suggests that the primary adduct is an N7-guanine adduct. The kinetics of the loss of this guanine and its transformation into the more stable secondary adduct resembled that reported recently for the major primary DNA adduct formed by the reaction of AFB1 at the N-7 position of guanine in the DNA of normal and XP cells and its transformation into the putative AFB1-ring opened triamino pyrimidyl structure.
- Published
- 1984
- Full Text
- View/download PDF
29. Polar polynuclear aromatic hydrocarbon derivatives in extracts of particulates: Biological characterization and techniques for chemical analysis
- Author
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D. Schuetzle, James C. Ball, and Trescott E. Jensen
- Subjects
lcsh:GE1-350 ,Diesel fuel ,Polynuclear aromatic hydrocarbon ,Chromatography ,Chemistry ,Particulate material ,Polar ,Organic chemistry ,Particulates ,Decomposition ,lcsh:Environmental sciences ,General Environmental Science ,Characterization (materials science) - Abstract
A protocol incorporating the concept of “bioasssay directed chemical analysis” has been developed for the analysis of polar polynuclear aromatic hydrocarbon (polar-PAH) derivatives in particulate matter samples. As an example of the protocol, results and are presented for a National Bureau of Standards (NBS) candidate standard reference diesel particulate material (SRM 1650). Good recovery of mutagenicity and mass suggests that compound decomposition/conversion was minimized. Identification of polar-PAH derivatives was undertaken for liquid chromatographic fractions of a heavy-duty diesel particulate extract that were found to contain a large portion of the total extract mutagenicity. Hydroxy-PAH, hydroxy-nitro-PAH, PAH-quinones, and nitrated heterocyclics were tentatively identified in the polar fractions of the diesel extract. The compounds of most interest at this time, because of their relatively high mutagenicity, are multifunctional nitrated-PAH (e.g., hydroxy-nitro-PAH) and nitrated-heterocyclics. Several new techniques are described that could greatly facilitate the identification of specific isomers of polar mutagens.
- Published
- 1985
30. Chemical reactivities and mutagenicities of a series of chloromethylbenzo[a]pyrenes
- Author
-
Alberto A. Leon, David L. Vander Jagt, Susan Foxall-Van Aken, Guido H. Daub, and James C. Ball
- Subjects
Magnetic Resonance Spectroscopy ,Chemical Phenomena ,Chemistry ,Mutagenicity Tests ,Chemical shift ,food and beverages ,General Medicine ,Nuclear magnetic resonance spectroscopy ,Carbocation ,Toxicology ,Mass Spectrometry ,Ames test ,chemistry.chemical_compound ,Kinetics ,Structure-Activity Relationship ,Solubility ,embryonic structures ,Structure–activity relationship ,Organic chemistry ,Solvolysis ,Methylene ,Benzopyrenes ,Mutagens - Abstract
The chemical and mutagenic properties of a series of chloromethylbenzo[a]pyrenes (chloromethyl-BaP) (chloromethyl groups in position 1-, 4-, 5-, 6-, 10-, 11- or 12-) were studied in order to address the question of the importance of arylmethyl carbocations as possible ultimate carcinogens of methylated polycyclic aromatic hydrocarbons (PAH). The rates of solvolysis of the series of chloromethyl-BaP in 50% aqueous acetone decrease in the order: 6 greater than 1 much greater than 4 greater than 12 greater than 5 greater than 10 greater than 11. There is a rough correlation (r = -0.80, P less than 0.05) between rates of solvolysis and the carbon chemical shifts of the methylene carbons. There is a good correlation (r = 0.98, P less than 0.001) between the rates of solvolysis and the gas phase stabilities of the carbocations, (M+ -35), obtained from mass spectral analysis. The mutagenicities of the series of chloromethyl-BaP in the Ames assay with strains TA98 and TA100 showed strong to very strong mutagenicities for the 4-, 5-, 10-, 11- and 12-isomers and weak mutagenicities for the 1- and 6-isomers. The corresponding hydroxymethyl-BaP were not mutagenic. The mutagenicities of some of the chloromethyl-BaP are among the highest reported for direct-acting (not requiring microsomal activation) mutagens in the Ames assay.
- Published
- 1985
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