Aromatic amines, soils

Oostdyk TS, Grob RL, Snyder JL, et al. 1995. Supercritical fluid extraction of primary aromatic amines from characterized soil samples comparison with sonication extraction. J Environ Sci Health A30(4) 783-816. 

Grob RL, Cao KB. 1990. High-performance liquid chromatographic study of the recovery of aromatic amine and nitro compounds from soil. J Environ Sci Health Part A Environ Sci Eng... 

Bimer, G Neumatm, H.-G (1988) Biomonitoring of aromatic amines. II Hemoglobin binding of some monocyclic aromatic amines. Arch. Toxicol., 62, 110-115 Bollag, J.-M., Blattmann, P. Laanio, T. (1978) Adsorption and transformation of four substituted anilines in soil. J. Am. Food Chem., 26, 1302-1306 Bull, D.L. (1973) Metabolism of chlordimefon in cotton plants. Environ. EntomoL, 2, 869-871 Chemical Information Services (1999) Directory of World Chemical Producers (Version 99.1.0) [CD-ROM], Dallas, TX... 

Fabrega, 3. R C. Jafvert, H. Li, and L. S. Lee, Modeling short-term soil-water distribution of aromatic amines , Environ. Sci. Technol., 32,2788-2794 (1998). 

Finally, mention must be made of possible conjugation reactions in which a covalent bond is formed between a contaminant molecule and a second contami nant molecule or soil organic matter. Oxidative coupling reactions of phenolics and aromatic amines are catalyzed by extracellular enzymes, clays, and oxides (Wang et al., 1986 Liu et al., 1987 Fluang, 1990). The bioavailability of the synthetic organic within the product is reduced or possibly eliminated (Dec et al., 1990 Allard et al., 1994). 

Supercritical fluid chromatography has been used to determine aromatic amines in soil [242-246]. 

Cohen and Wheals [185] used a gas chromatograph equipped with an electron capture detector to determine 10 substituted urea and carbamate herbicides in river water, soil and plant materials in amounts down to 0.001-0.05ppm. The methods are applicable to those urea and carbamate herbicides that can be hydrolysed to yield an aromatic amine. A solution of the herbicide is first spotted on to a silica gel G plate together with herbicide standards (5-10pg) and developed with chloroform or hexane-acetone (5 1). The plate containing the separated herbicide or the free amines is sprayed with 1-fluoro-1,4-dinitrobenzene (4% in acetone) and heated at 190°C for 40min to produce the 2,4-dinitrophenyl derivative of the herbicide amine moiety. Acetone extracts of the areas of interest are subjected to gas chromatography on a column of 1% of XE-60 and 0.1% of Epikote 1001 on Chromosorb C (AE-DCMS) (60-80 mesh) at 215°C. 

The most studied kinds of explosives are nitroaromatic explosives and their metabolites. Therefore, the emphasis of this review is on properties of nitroaromatic explosives, rather than propellants, pyrotechnics, or munitions, and their interactions with soils. Nitroaromatic explosives are toxic, and their environmental transformation products, including arylamines, arylhydroxyl-amines, and condensed products such azoxy- and azo-compounds, are equally or more toxic than the parent nitroaromatic [3]. Aromatic amines and hydroxylamines are implicated as carcinogenic intermediates as a result of nitrenium ions formed by enzymatic oxidation [4], Aromatic nitro compounds... 

Li, H., Lee, L.S., Jafvert, C.T., Graveel, J.J. (2000) Effect of substitution on irreversible binding and transformation aromatic amines with soils in aqueous systems. Environ. Sci. Technol. 34, 2674—3680. 

The phenoloxidase enzymes (peroxidases, tyrosinases, and laccases) are known to occur extracellularly in soils (16,17), and have been considered to play a role in catalyzing the coupling of aromatic amines to humic substances (3). Peroxidases have been studied most extensively. They use hydrogen peroxide to promote the one electron oxidation of aromatic amines and of phenolic moieties within humic substances to form free radicals. (12,18). 

The liquid phase NMR spectra comprise the first direct spectroscopic evidence differentiating phenoloxidase- and metal-catalyzed reactions from noncatalyzed nucleophilic addition reactions of aniline with humic substances. The solid state NMR spectra provide the first direct evidence for nucleophilic addition of aniline to quinone and other carbonyl groups in the organic matter of whole soil and peat. The NMR approach has potential for further investigation of the effects of reaction conditions on the incorporation of aromatic amines into naturally occurring organic matter, and for studies on how aromatic amines covalently bound to organic matter may ultimately be re-released or remineralized, either chemically or microbially. 

Although oxidation can occur in soil solution by reaction with dissolved oxygen, the reaction is often much more rapid in the presence of surfaces that serve as oxidizing agents or catalysts. For example, benzidine, an aromatic amine, is adsorbed on smectites as an organic cation, and is subsequently oxidized rapidly by structural iron ... 

P, primary amine S, secondary amine T, tertiary amine A, ammonia N, nitrosamine AA, aromatic amine PA, polyamine Al, aliphatic amine A, air H, water S, soil W, waste. 

Similar studies, however, suggest that N-nitrosobutalin will be quite persistent in soils (Oliver and Konston, 1978). Reduction of N-nitrosopendimethalin has been observed in anaerobic soils (Smith et al., 1979). Product studies indicate, however, that the nitroso moiety remains intact and reduction of the aromatic nitro group in the 6-position occurs to give the aromatic amine (Equation 3.36). 

Oasis HLB was successfully used for SPE and trace enrichment in the determination of phenols in water [300, 301], tetracycline, macro-lide, and sulfonamide antibiotics in aqueous media and agricultural soils [302—305], various pharmaceuticals in plasma and serum [306— 308], herbicides in natural waters [309-311], polycyclic aromatic hydrocarbons (PAHs) in plants [312], aromatic amines in mainstream cigarette smoke [313], as well as many other types of compounds [314-319],... 

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