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6018046 
Journal Article 
Reactions of Chlorine Dioxide With Aquatic Organic Materials and Their Health Effects 
Rav-Acha, C 
1984 
One of the most promising of alternatives to water chlorination is treatment with chlorine dioxide which does not lead to the formation of trihalomethanes (THM). Chlorine dioxide reacts primarily as a one-electron acceptor, in contrast to chlorine which acts via a variety of electrophilic, oxidative, and radical pathways. Consequently, the reactions of ClO2 are much more selective and specific than those of chlorine. Chlorine seems to be more efficient for the general removal of aquatic organics (TOC); if the primary consideration is to avoid the formation of harmful by-products, then ClO2 may be the disinfectant of choice. One of the major weaknesses of ClO2 is that upon reaction with aquatic organics, abour 50% of it is converted to chlorite. The more desirable water treatment should include physical processes to reduce the organic content prior to disinfection. The principle organic by-products formed by ClO2 in drinking water would probably be quinones and hydroquinones produced by the reaction of ClO2 with aquatic humic and fulvic acids. This is in addition to low molecular weight aldehydes and carboxylic acids. Although most of the aldehydes (with the exception of formaldehyde and alpha-keto-aldehydes) and carboxylic acids are generally considered to be non-toxic, some quinones and hydroquinones have recently been found to possess negative biological activities (Trevors, J.T. and J. Bursuraba, 1980. Bull. Environ. Contam. Toxic., Vol. 25, p 672-675). (Collier-IVI) 
Water Resources Abstracts; Disinfectants; Cholorine dioxide; Chlorination; Toxicity Chemical reactions; Water pollution effects; Trihalomethanes; Humic acids; Fulvic acids; Aldehydes; Carboxylic acids; Quinones