Toxicity of aromatic compounds

Cronin, M.T.D. and Schultz, T.W. 2001. Development of quantitative structure-activity relationships for the toxicity of aromatic compounds to Tetrahymena pyriformis Comparative assessment of the methodologies. Chem. Res. Toxicol. 14 1284-1295. 

Cronin MTD, Manga N, Seward JR, Sinks GD, Schultz TW. Parametrization of electrophilicity for the prediction of the toxicity of aromatic compounds. Chem Res Toxicol 2001 14(ll) 1498-505. 

Netzeva, T.I., Dearden, J.C., Edwards, R., Worgan, A. D.P. and Cronin, M.T.D. (2004) QSAR analysis on the toxicity of aromatic compounds to Chlordla vulgaris in a novel short-term assay. J. Chan. Inf. Comput. Sci., 44, 258-265. 

Laszlo, T. Beteringhe, A. QSAR studies related to toxicity of aromatic compounds on Tetrahymena pyrifotmis. QSAR Comb. Sci. 2006, 25, 944—951. 

SVM Regression QSAR for the Toxicity of Aromatic Compounds to CMorella vulgaris... 

Comput. Sci., 44,258-265 (2004). QSAR Analysis of the Toxicity of Aromatic Compounds to Chlorella vulgaris in a Novel Short-term Assay. 

Except for polybrominated biphenyls (PBB), a limited number of studies regarding the toxicity of aromatic brominated compounds has been performed. Some experiments suggest a moderate acute toxicity of these compounds (ref. 1). 

Daly JW, DM Jerina, B Witkop (1972) Arene oxides and the NIH shift the metabolism, toxicity and carcinogenicity of aromatic compounds. Experientia 28 1129-1149. 

The physiological effects of the fluoride ion were reviewed by McClure 74) in 1933. Lehmann 72) published an article on the toxicity of aromatic fluorine compounds in 1928. However, it has been impossible to investigate the toxicity of the organofluorine compounds as thoroughly as that of the organochlorine compounds. 

The heat of decomposition (238.4 kJ/mol, 3.92 kJ/g) has been calculated to give an adiabatic product temperature of 2150°C accompanied by a 24-fold pressure increase in a closed vessel [9], Dining research into the Friedel-Crafts acylation reaction of aromatic compounds (components unspecified) in nitrobenzene as solvent, it was decided to use nitromethane in place of nitrobenzene because of the lower toxicity of the former. However, because of the lower boiling point of nitromethane (101°C, against 210°C for nitrobenzene), the reactions were run in an autoclave so that the same maximum reaction temperature of 155°C could be used, but at a maximum pressure of 10 bar. The reaction mixture was heated to 150°C and maintained there for 10 minutes, when a rapidly accelerating increase in temperature was noticed, and at 160°C the lid of the autoclave was blown off as decomposition accelerated to explosion [10], Impurities present in the commercial solvent are listed, and a recommended purification procedure is described [11]. The thermal decomposition of nitromethane under supercritical conditions has been studied [12], The effects of very high pressure and of temperature on the physical properties, chemical reactivity and thermal decomposition of nitromethane have been studied, and a mechanism for the bimolecular decomposition (to ammonium formate and water) identified [13], Solid nitromethane apparently has different susceptibility to detonation according to the orientation of the crystal, a theoretical model is advanced [14], Nitromethane actually finds employment as an explosive [15],... 

One of numerous examples of LOX-catalyzed cooxidation reactions is the oxidation and demethylation of amino derivatives of aromatic compounds. Oxidation of such compounds as 4-aminobiphenyl, a component of tobacco smoke, phenothiazine tranquillizers, and others is supposed to be the origin of their damaging effects including reproductive toxicity. Thus, LOX-catalyzed cooxidation of phenothiazine derivatives with hydrogen peroxide resulted in the formation of cation radicals [40]. Soybean LOX and human term placenta LOX catalyzed the free radical-mediated cooxidation of 4-aminobiphenyl to toxic intermediates [41]. It has been suggested that demethylation of aminopyrine by soybean LOX is mediated by the cation radicals and neutral radicals [42]. Similarly, soybean and human term placenta LOXs catalyzed N-demethylation of phenothiazines [43] and derivatives of A,A-dimethylaniline [44] and the formation of glutathione conjugate from ethacrynic acid and p-aminophenol [45,46],... 

Diesel-like products (jet fuel, diesel. No. 2 fuel oil, kerosene) are moderately volatile products that can evaporate with no residue. They have a low-to-moderate viscosity, spread rapidly into thin slicks, and form stable emulsions. They have a moderate-to-high (usually, high) toxicity to biota, and the specific toxicity is often related to type and concentration of aromatic compounds. They have the ability to penetrate substrate, but fresh (unoxidized) spills are nonadhesive. 

The experimentally observed sequence of toxicities of several polycyclic aromatics (3) is listed in Table I. Benzene is the least toxic and naphthalene the most toxic of the compounds investigated. The toxicity of naphthalene decreases, however, when bulky inert substituents such as F, Cl, and CHj are introduced. 

The chloroperoxidase of C. fumago was able to transform 17 of 20 PAHs assayed [100]. In this case, only halogenated products were observed, and no oxygenated products could be detected. This biocatalytic transformation should be carefully considered because the toxicity and environmental impact of aromatic compounds may be increased. 

SYN CHLORINATED HC AROMATIC SAFETY PROFILE In most instances, it is difficult to predict the toxicity of these compounds. However, in the case of most... 

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