Drinking water chlorine

At present, chlorine dioxide is primarily used as a bleaching chemical in the pulp and paper industry. It is also used in large amounts by the textile industry, as well as for the aching of flour, fats, oils, and waxes. In treating drinking water, chlorine dioxide is used in this country for taste and odor control, decolorization, disinfection, provision of residual disinfectant in water distribution systems, and oxidation of iron, manganese, and organics. The principal use of chlorine dioxide in the United States is for the removal of taste and odor caused by phenolic compounds in raw water supplies. 

Pyrene is a common PAH contaminant and may occur in drinking water. Chlorination of water with or without bromide that may be present in coastal environments has been examined. Both chlorinated and brominated pyrenes with halogen substituents at the 1,3-, 1,6-, and 1,8-positions were found, and could putatively be produced by reaction of pyrene with hypochlorous acid and hypochlorite (Hu et al. 2006). 

In addition to drinking water, chlorinated oxidants reacting with organic materials will lead to the formation of chloroform in swimming pools. Since swimming pools are not routinely analyzed for their chloroform content, data are limited and derived from special studies. Such studies will often cover the broader family of THMs, and while chloroform levels in blood or alveolar air samples will be reported, the environmental agents will often simply be recorded in terms of THMs. A rule of thumb (Copaken 1990) is... 

Alavanja M, Goldstein I, Susser M. 1978. A case control study of gastrointestinal and urinary tract cancer mortality and drinking water chlorination. In Jolley RJ, Gorchen H, Hamilton DH Jr., eds. Water... 

Young TB, Kanarek MS, Tsiatis AA. 1981. Epidemiologic study of drinking water chlorination and Wisconsin female cancer mortality. J Natl Cancer Inst 67 1191-1198. 

Kallen BAJ, Robert L. 2000. Drinking water chlorination and delivery outcome—a registry-based study in Sweden. Reprod Toxicol 14 303-309. 

Chlorinated Drinking-water Chlorination By-products Some Other Halogenated Compounds Cobalt and Cobalt Compounds... 

I ARC (1991) lARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Vol, 52, Chlorinated Drinking-Water Chlorination By-Products Some Other Halogenated Compounds Cobalt and Cobalt Compounds, Lyon, pp. 337-359... 

Considerable information of a general nature is available for uncontaminated water subject to the production of disinfection byproducts. The mutagens produced by drinking water chlorination appear to be numerous, but they exist either at low levels or are of low potency. For both the unresolved mixtures and for the few mutagenic compounds thus far identified, activity is readily reduced or destroyed by treatment with alkali or 4-nitrothiophenol and may be removed by GAC treatment. From water sources subject both to mutagen formation via disinfection and to periodic contamination by toxic chemicals, experimental full-scale GAC treatment systems have provided mutagen-free water. 

We live in a time when 1.1 billion people lack access to safe drinking water. Chlorine powders, such as sodium hypochlorite, NaCIO, however, can provide a family with safe drinking water for as little as 10 cents/day. What agencies or institutions should be involved... 

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]. 

Water Quality and Health Council. Drinking water chlorination. A review of disinfection practices and issues, www.waterandhealth.org/drinkingwater/ wp.html... 

Koivusalo M, Vartiainen T. Drinking water chlorination by-products and cancer. Rev Environ Health 1997 12(2) 81—90. 

Mills, CJ, Cantor RJ, Reif J, et al. Health risks of drinking water chlorination byproducts Report of an expert working group. CDIC1998 19(3) 1-17. 

Phthalate and adipate esters in drinking water Chlorinated pesticides in water 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD)... 

A few court decisions, however, have been more skeptical of the linear model. Eor example, the U.S. EPA s use of the linear, no-threshold model in its risk assessment for drinking water chlorinated byproducts was rejected by the court because it was contrary to evidence suggesting a nonlinear model that had been accepted by both the U.S. EPA and its Science Advisory Board (CCC 2000). On the other hand, the U.S. OSHA s departure from the linear, no-threshold model in its formaldehyde risk assessment was likewise rejected by the court (lU 1989). The court held that the U.S. OSHAhad improperly used the maximum likelihood estimate (MLE) rather than the upper confidence limit (UCL) to calculate risk, and the UCL but not the MLE model was consistent with a linear dose-response assumption. The court held that the U.S. OSHA had failed to justify its departure from its traditional linear, no-threshold dose-response assumption. 

Total trihalomethanes (TTHM) Possible cancer risk 0.1-0 Chloroform, drinking water chlorination byproduct... 

Waste water chlorination is even older than drinking water chlorination. It makes use of the toxicological, oxidative and coagulant properties of chlorine. Besides the main target, the disinfection, chlorine is used to deodorize the waste water, e.g in presence of hydrogen sulfides, to decolorize, to retard putrefaction, to reduce the biochemical oxygen demand (BOD), and to ease the filtration by improved coagulation. 

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