Effects of Nitroaromatic Compounds

Antimutagenic activity of bis(D,L-lactato)-, bis(L-lactato)-, bis(thiolacetato)- and bis (thioglycolato)germanium(rV) has been tested in Salmonella typhimurium strains TA98 and TAIOO. They showed moderate activity against the mutagenic effect of nitroaromatic compounds . ... 

Effects of Nitroaromatic Compounds on the Soil Microbial Community... 

Comparative studies revealed that the lethal concentrations of ETNT, 2,4-DANT, and TNB were lower for amphipods than other invertebrates [8,9,13] (Table 5.2), suggesting a potentially high relative sensitivity of amphipods to sediment-associated nitroaromatic compounds. Amphipods and other crustaceans were also relatively sensitive to the toxic effects of nitroaromatic compounds compared to other invertebrate taxa and fish in water-only exposures (see Chapter 4). Therefore, the use of amphipods to assess the toxicity investigations of sediments from explosives-con-taminated sites is recommended to assure reasonable protectiveness. 

Hathaway J A Subclinical effects of trinitrotoluene A review of epidemiology studies. In Richert DE (ed) Toxicity of Nitroaromatic Compounds, pp 255-274. New York, Hemisphere Publishing, 1985... 

P 14.6 Evaluating the Effect of Substituents on the One-Electron Reduction Potentials of Nitroaromatic Compounds... 

Hofstetter T. B. Neumann A. Arnold W. A. Hartenbach A. E. Bolotin J. Cramer C. J. Schwarzenbach R. P. Substituent effects on nitrogen isotope fractionation during abiotic reduction of nitroaromatic compounds. Environ. Sci. Technol. 2008, 42, 1997-2003. 

The most powerful methods for the study of adsorption mechanism of nitroaromatic compounds on clay minerals have become in situ spectroscopic investigations. Handerlein et al. [152, 153] and Weissmahr et al. [154-156] have investigated the adsorption of NACs particularly on illites, montmorillonites and homoionic kaolinites. The substituted nitrobenzenes on the surface of smectites were investigated by Boyd et al. [157, 158], The main focus in the experimental study of adsorption of NACs on the surface of clay minerals is the influence of the type of clay mineral, the effect of exchangeable cation of the mineral, the effect of the structure and the kind of substituents of NAC compound on the position and orientation of NACs to the surface of mineral, the character of interaction between NACs and the surface of mineral, the adsorption energy. 

The obtained results enable the following conclusion. The calculated value of interaction energy between the nitrobenzene molecule and the partially hydrated surface of the clay minerals is very close to the interaction energy between the NAC molecules and the nonhydrated surface. This finding combined with the experimental data of the adsorption of nitroaromatic compounds on the hydrated surface of clay minerals indicates that this type of adsorption should be at least as effective as the adsorption, which includes coplanar interactions of TNB with nonhydrated silicon-oxygen surfaces. 

Electrode surface activation can be improved simply by electrochemical pretreatment. Determination of nitroaromatic compounds in water and soil spiked samples have been reported at electrochemically activated carbon-fiber microelectrodes. No interference was found from compounds such as hydrazine, phenolic compounds, carbamates, triazines or surfactants. The detection limit obtained can be approximately 0.03 iigml-1 for all the nitroaromatic compounds (Agui et al. 2005). Chen and coworkers reported an effective field-deployable tool for detecting nitroaromatic compounds with an electrochemically pre-anodized screen-printed carbon electrode (SPE) (Chen et al. 2006). 

Ascorbate Potentiated Cytotoxicity of Nitroaromatic Compounds. Extensive research aimed at finding chemicals or chemical systems that will sensitize hypoxic cells, which are ordinarily very resistant to radiation or chemicals, is being conducted in the field of radiobiology. Of particular interest are the investigations (58-6J) of the catalytic effect of certain carcinogens upon the oxidation of ascorbate. 4-Nitroquinoline N-oxide (4-NQO), which is one of many compounds (52,62,63) that mediate the ascorbate-oxygen reaction, is used as an example. 

Research on the effects of nitroaromatic EMs on terrestrial plants has taken a long and winding path that has yet to reach its destination. Early studies were mainly designed to demonstrate that newly developed explosives were not highly phytotoxic or focused on assessing the effects of TNT and related compounds associated with pink water waste on aquatic plants [33-35], Schott and Worthley [34] found that the growth of Lemna perpusilla Torn was reduced at TNT concentrations of 1 mg L 1... 

The fate of explosive compounds in soils has been well characterized [6] and was reviewed in Chapter 2 of this book. In contrast, reports on the fate and biological effects of explosives and related compounds in sediments are scarce, despite the potential ecological risk associated with their presence in this compartment of aquatic environments. Recent studies characterizing the processes that occur following the initial contact of explosives and related compounds with sediments revealed rapid rates of transformation for a variety of nitroaromatic compounds [7-14], Investigations of the toxicity of sediment-associated explosives were relatively recent and used sediment amended with contaminants in the laboratory [8-11,13,14],... 

The nitro group in the ortho- or para-positions is one of the strongest electron-withdrawing substituent, activating an aromatic ring for a nucleophilic attack [5]. No wonder that a great deal of both oxidative and eliminative Sn reactions have been observed in the series of nitroaromatic compounds [11, 15-18, 25, 27, 28, 30-32, 36, 37, 97-100]. The VNS protocol has been particularly effective for the Sn reactions of a large number of nitro-substituted aromatic and heteroaromatic compounds [11-18, 25, 27, 28, 30-32, 36, 37, 45, 98-100], as illustrated by nucleophilic alkylation of 3-nitropyridine with vicarious methyl chloroacetate (Scheme 22) [100]. 

Abstract - This work is concerned with the origin of effects on rate equilibrium processes when reactions are performed in dipolar aprotic media such as dimethyl sulfoxide and dimethyl-formamide compared to typical hydroxylic media. An example of processes studied in our laboratory is the competition between proton abstraction and a-complex (Meisenheimer adduct) formation in the interaction of nitroaromatic compounds with basic systems (e.g. 1,3-dinitrobenzene in DMF-D20-Na0D). Other reactions studied are the base catalyzed isotopic exchange of D2 in aqueous DMSO mixtures, and also isotopic exchange of fluoroform. It has been found possible in certain cases to dissect the initial state and transition state contributions to the reaction rates from the kinetically measured enthalpies of activation and the thermodynamically evaluated enthalpies of transfer of the reactants. This procedure affords insight into transition state properties and behaviour. 

NCI mass spectra of nitroaromatic compounds usually contain M" and [M — H] ions, whose relative abundance depends on the specific compounds and the reactant ions. In compounds such as TNT, where the ortho effect may operate, an [M — OH] is observed. 

Aromatic nitroso compounds usually are considered to be intermediates in the hydrogenation of a nitroaromatic compound to the aromatic hydroxyl-amine or amine. However, nitroso compounds do not accumulate in these reductions, suggesting that they are reduced more easily than are nitro compounds. Catalysts effective for the nitro group should also be effective for nitroso. 

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