Chlorine humic substances

Matsuda H, Hibino M, Sato T, et al. 1993a. Mutagenicity of ozonated and chlorinated humic substances. J Environ Sci Health Part A 28 821-837. 

Hydrodechlorination is a common reaction of chlorinated pesticides such as atrazine (eq. 15), alachlor, and metolachlor (2) (eq. 16). These reactions are catalyzed primarily by transition metals or by soil surfaces (clays or humic substances). 

Tanaka F, Fukushima M, Kikuchi A, Yabuta H, Ichikawa H, Tatsumi K (2005) Influence of chemical characteristics of humic substances on the partition coefficient of a chlorinated dioxin. Chemosphere 58 1319-1326... 

Sabljic, A., Lara, R., Ernst, W. (1989) Modelling association of highly chlorinated biphenyls with marine humic substances. Chemosphere 19, 1665-1676. 

Gaffney et al. 1987). Cyanogen chloride is formed in drinking water from reaction of humic substances with chloramine produced during chlorination (Jacangelo et al. 1989 Ohya and Kanno 1987). 

Photolytic. Photoproducts reported from the sunlight irradiation of propanil (200 mg/L) in distilled water were 3 -hydroxy-4 -chloropropionanilide, 3 -chloro-4 -hydroxypropionanilide, 3, 4 -di-hydroxypropionanilide, 3 -chloropropionanilide, 4 -chloropropionanilide, propionanilide, 3,4-di-chloroaniline, 3-chloroaniline, propionic acid, propionamide, 3,3, 4,4 -tetrachloroazobenzene, and a dark polymeric humic substance. These products formed by the reductive dechlorination, replacement of chlorine substituents by hydroxyl groups, formation of propionamide, hydrolysis... 

Zhang X, Minear RA (2006) Formation, adsorption and separation of high molecular weight disinfection byproducts resulting from chlorination of aquatic humic substances. Water Res 40(2) 221-230... 

Zhang X, Minear RA, Barrett SE (2005) Characterization ofhigh molecular weight disinfection byproducts from chlorination of humic substances with/without coagulation pretreatment using UF-SEC-ESI-MS/MS. Environ Sci Technol 39(4) 963-972... 

Elemental Analysis. The elemental analyses are presented in Table IV. The atomic ratios H/C for all drinking water samples (nos. 1-10) were between 1.28 and 1.39. These values were comparable to humic acid derived from lake sediments. However, H/C ratios were much lower when compared to the chlorinated model humic substances (e.g., 1.04-1.08 for CFH-1 and CFH-2). Bromine was present in almost negligible quantities, whereas Cl varied between 0.3 and 2.4, and S varied between 0.9 and 2.7 in the drinking water organic matter. All fractions from drinking water showed similar elemental composition. However, they differed from the elemental composition of the CFH samples in all respects, especially in chlorine content. 

Concentrated extracts of many drinking waters in the United Kingdom and elsewhere are mutagenic as observed in bacterial assays (i-3). Compounds that are widely distributed in the aquatic environment, such as humic substances and amino acids, have been found to react with chlorine to produce mutagenic compounds (4, 5). These compounds may account for at least some of the mutagenic activity of extracts of drinking waters. 

Tribromomethane [75-25-2] (bromoform), CHBr3, is usually sold mixed with up to 3—4% ethanol as a stabilizer. The pure liquid has mp, 7.7°C bp, 149.5°C cP A, 2.8912 g/mL 19D 1.5980 (87). Water solubility is about 0.3 g/100 g at 25°C. Bromoform is prepared from chloroform by the replacement procedures indicated (88). The classical method of preparation involves reaction of acetone and sodium hypobromite the latter may be generated from sodium hypochlorite and a bromide (89). Uses have been found in syntheses, in pharmacy as a sedative and antitussive, in gauge fluids, and as a dense liquid for separating minerals. Traces of bromoform and bromochloroforms are likely to be present in municipal waters and wastes as a result of chlorination in the presence of naturally occurring bromide ions and humic substances (90). Removal can be accomplished by adsorption on activated charcoal. 

Michaelis W, Richnow HH, Seifert R (1995) Chemically Bound Chlorinated Aromatics in Humic Substances. Naturwissenschaften 82 139... 

Reactions of Chlorine and Chlorine Dioxide with Humic Substances 694... 

Carvalho, E. R. (2003). Study of trihalomethanes formation from aquatic humic substances treated by chlorine and chlorine dioxide. Ph.D. thesis, University of Sao Paulo-USP, Brazil. 

Christman, R.F., Norwood, D.L., Webb, M.R. and Robenrath, M.J. US National Technical Information Service, Springfield, Virginia. Report No. PB8H61962 Chlorination of Aquatic Humic Substances (1981). 

Choi, W.-W., Chen, K.Y. (1976) Associations of chlorinated hydrocarbons with fine particles and humic substances in nearshore surficial sediments. Environ Sci. Technol. 10(8), 782-786. 

Because of their extensive use in industrial activities, phenolic compounds are abundant in many wastewaters. They are present in oil refining, petrochemical, plastic, pesticide, carbon liquefaction, and food processing industrial wastewaters. In addition, phenol-like structures are part of the macromolecular natural humic substances present in water humics are known precursors of trihalomethane compounds in drinking water chlorination [176,177], These compounds are refractory to conventional processes such as biological oxidation because of their toxicity for microorganisms [178]. 

ROLE OF HUMIC SUBSTANCES IN THE ENVIRONMENTAL CHEMISTRY OF CHLORINATED PHENOXYALKANOIC ACIDS AND ESTERS... 

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