Disinfection chlorine

Povidone—iodine is a brown, water-soluble powder containing approximately 10% iodine. However, the amount of free iodine, which is responsible for the antimicrobial activity, is low in a concentrated solution, but is released as the solution is diluted (41). Concentrated solutions have actually been contaminated with bacteria (42). For use as an antiseptic, povidine—iodine is diluted with water or alcohol to a concentration of 1% iodine. Detergents are added if it is used as a surgical scmb. lodophors are important as broad-spectmm antiseptics for the skin, although they do not have the persistent action of some other antiseptics. They are also used as disinfectants for clinical thermometers that have been used by tuberculous patients, for surface disinfection of tables, etc, and for clean equipment in hospitals, food plants, and dairies, much as chlorine disinfectants are used. 

Connell GE (2006) Key operation strategies for chlorine disinfection operating systems. Proceedings of WEFTEC, Water Environment Federation... 

In addition, brominated derivatives of alkylphenols (BrNPnEO and BrNPnEC) can be formed during chlorine disinfection of water if... 

In more recent in-depth investigations on this issue [22], a series of chlorinated and brominated by-products of alkylphenolic surfactants and their degradation intermediates formed during chlorine disinfection of raw water were identified using mass spectrometry (Table 6.6.2). 

Determination of Chlorinated Disinfection Byproducts and Chlorinated Solvents in Drinking Water by LLE and GC... 

Oyler, A.R., Llukkonen, R.J., Lukasewycz, M.T., Heikkila, K.E., Cox, D.A., and Carlson, R.M. Chlorine disinfection chemistry of aromatic compounds. Polynuclear aromatic hydrocarbons rates, products, and mechanisms. Environ. Sci. Technol, 17(6) 334-342, 1983. 

Pinkston KE, Sedlak DL (2004) Transformation of aromatic ether- and amine-containing pharmaceuticals during chlorine disinfection. Environ Sci Technol 38 4019 025... 

Nieuwenhuijsen MJ, Toledano MB, Eaton NE, Fawell J, Elliott P (2000) Chlorination disinfection byproducts in water and their association with adverse reproductive outcomes a review. Occup Environ Med 57(2) 73-85... 

Zhao Y, Qin F, Boyd JM, Anichina J, Li XF (2010) Characterization and determination of chloro- and bromo-benzoquinones as new chlorination disinfection byproducts in drinking... 

Kuhlich P, Gostl R, Teichert P, Piechotta C, Nehls I (2011) Transformation of polycyclic musks AHTN and HHCB upon disinfection with hypochlorite two new chlorinated disinfection by-products (CDBP) of AHTN and a possible source for HHCB-lactone. Anal Bioanal Chem 399 3579-3588... 

Takeuchi, K. and Frank, J. F. (2001). Quantitative determination of the role of lettuce leaf structures in protecting Escherichia coli 0157 H7 from chlorine disinfection. J. Food Prot. 64, 147-151. 

Anderson AC, Reimers RS, DeKemion P. 1982. A brief review of the current status of alternatives to chlorine disinfection of water. Am J Public Health 72(11) 1290-1293. 

Disinfection by-products (DBPs) form an undesired species in the chlorine disinfection processes of waters (performed with chlorine, chlorine dioxide, and chloramines). The high priority DBPs include brominated, chlorinated, and iodinated species of halomethanes, brominated, and chlorinated forms of haloacetonitriles, haloketones, haloacids, and halonitromethanes, as well as analogues of 3-chloro-(4-dichloromethyl)-5-hydroxy-2(5//)-furanone. All the high priority DBPs included in the Nation-wide DBP occurrence study are listed in Table 18.1 together with other contaminants. 

Because chlorine is inactivated by blood, serum, feces, and protein-containing materials, surfaces should be cleaned before chlorine disinfectant is applied. Undissociated hypochlorous acid (HOCI) is the active biocidal agent. When pH is increased,... 

Daniel, F.B., Schenck, K.M., Mattox, J.K., Lin, E.L., Haas, D.L. Pereira, M.A. (1986) Genotoxic properties of haloacetonitriles drinking water by-products of chlorine disinfection. Fundam. appl. Toxicol., 6, 447-453... 

Influence of Hypochlorite on Parfait Columns. One potential use of the parfait method is the recovery of organic matter from drinking water. To test for the interaction of chlorine disinfectant with column components or eluents, the influence of 2 ppm of hypochlorite was assessed in an unspiked control column. Each eluate was assayed for hypochlorite by using the ferrous N,N-diethyl-p-phenylenediamine titrimetric method (12). No hypochlorite was detected. Each eluate was also analyzed by GC and found to be virtually identical to a blank column without hypochlorite run simultaneously. 

Disinfection with Chlorine and Chlorine Dioxide. The comparison of the mutagenic activity of the DCM extract before and after disinfection treatment was studied by the Wilcoxon test. No statistical conclusions on disinfection effects can be drawn. However, the MeOH extract showed a significant decrease in mutagenic activity for the line 2 chlorine treatment. Comparison of the two disinfection treatments for the nonozonated GAC filtered water (treatment line 4) shows that chlorine disinfection yields greater mutagenic activity of the DCM extract than chlorine dioxide (Table V). 

The 1978 Guidelines for Canadian Drinking Water Quality included phenols (for organoleptic reasons), biocides, and THMs. Nitrilotriacetic acid (NTA) was included because of its use as a constituent ofdaundry detergents, most of which are disposed into surface waters. Studies with rodents have shown that very large doses of NTA can result in an increased incidence of urinary tract tumors. THMs were included because of their production during the process of chlorine disinfection. 

It is worthwhile mentioning that ozone is frequently used for swimming pool water clean-up prior to a chlorine disinfection step. According to Bohme (1999) almost 3600, i. e. more than 50 % of the ozone generators sold by German companies between 1954 and 1997, have been efficiently applied in this field. 

This oxidative reaction with UV/VIS-active substances induces molecular changes, but not mineralization. These changes are also the basis for the production of biodegradable metabolites and the formation of smaller molecules with a higher hydrophilicity that tend to form less DBPs with the chlorine disinfectant. 

In the control of chlorine disinfectant systems, the effective use of the chlorine for its intended purpose is assumed if the treated water considerably downstream from the chlorinalor contains a residual of chlorine. Depending upon use. lull-contact tinte may be assumed alter len miuules. or the interval may be extended lo several hnurs. The systems also are usually carefully monitored by bacteriological testing. Normally a dose of I lo 2 milligrams of chlorine per liter is adequate lo destroy all bacteria and leave an effective residual. Residuals of 0.1 to 0.2 milligrams per liter are usually maintained in the diluent streams front water-treatment plants as a factor of safely for consumers. 

Of all the food categories, dairy products also contain one of the higher frequencies of industrial chemicals (see Exhibit 2). This is expected because these industrial chemicals tend to accumulate in the fat of dairy products. The diversity of the chemicals found in dairy products, however, occurs for several reasons. Because chloroform is a byproduct of using a chlorine disinfectant, it would appear that a significant number of dairy producers in the United States either do not rinse or do not completely rinse their equipment after disinfection2. Another source of disinfection byproducts is from water that may be used in a dairy. Benzene, toluene, ethyl benzene, and xylenes and the other detected chlorinated petroleum solvents (e.g., CBZ, DCE, PCE, TCA, and TCE) occur in dairy foods is because (1) these chemicals were in products used to lubricate or clean machinery that contacted the dairy products or (2) these chemicals were in the ambient air of the dairy. 

It should also be noted that at least five dairy products were contaminated with both chloroform and bromodichloromethane (i.e., associated with both bromine and chlorine disinfection). 

Because chlorine is inactivated by blood, serum, feces, and protein-containing materials, surfaces should be cleaned before chlorine disinfectant is applied. Undissociated hypochlorous acid (HOC1) is the active biocidal agent. When pH is increased, the less active hypochlorite ion, OC1 , is formed. When hypochlorite solutions contact formaldehyde, the carcinogen /v.v-chloromethyl is formed. Rapid evolution of irritating chlorine gas occurs when hypochlorite solutions are mixed with acid and urine. Solutions are corrosive to aluminum, silver, and stainless steel. 

The reduction of aqueous chlorine (HOC1) to chloride by Fe° and other ZVMs [Eq. (5)] has long been known as a major contributor to the decay of residual chlorine disinfectant during distribution in drinking water supply systems that contain metal pipes (e.g., Ref. 82). This reaction can, however, be turned to advantage for the removal of excess residual chlorine, and a variety of proprietary formulations of granular ZVMs are available commercially for this purpose (e.g., KDF Fluid Treatment, Inc. Three Rivers, MI). This application is sometimes called dechlorination, but should not be confused with the dechlorination of organic contaminants, which is discussed below. 

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