【国外标准】 Standard Test Methods for Bromate, Bromide, Chlorate, and Chlorite in Drinking Water by Suppressed Ion Chromatography

4.1 The oxyhalides chlorite, chlorate, and bromate are inorganic disinfection by-products (DBPs) of considerable health risk concern worldwide. The occurrence of chlorite and chlorate is associated with the use of chlorine dioxide, as well as hypochlorite solutions used for drinking water disinfection. The occurrence of bromate is associated with the use of ozone for disinfection, wherein naturally occurring bromide is oxidized to bromate. Bromide is a naturally occurring precursor to the formation of bromate.1.1 These multi-test methods cover the determination of the oxyhalides—chlorite, bromate, and chlorate, and bromide, in raw water, finished drinking water and bottled (non-carbonated) water by chemically and electrolytically suppressed ion chromatography. The ranges tested using these test methods for each analyte were as follows:  Range SectionsTest Method A:Chemically Suppressed Ion Chromatography   8 to 20 Chlorite 5 to 500 µg/L   Bromate 1 to 25 µg/L   Bromide 5 to 250 µg/L   Chlorate 5 to 500 µg/L       Test Method B:Electrolytically Suppressed Ion Chromatography   21 to 31 Chlorite 20 to 1000 µg/L   Bromate 1 to 30 µg/L   Bromide 20 to 200 µg/L   Chlorate 20 to 1000 µg/L  1.1.1 The upper limits may be extended by appropriate sample dilution or by the use of a smaller injection volume. Other ions of interest, such as fluoride, chloride, nitrite, nitrate, phosphate, and sulfate may also be determined using these test methods. However, analysis of these ions is not the object of these test methods.1.2 It is the user’s responsibility to ensure the validity of these test methods for waters of untested matrices.1.3 These test methods are technically equivalent with Part B of U.S. EPA Method 300.1,2 titled “The Determination of Inorganic Anions in Drinking Water by Ion Chromatography.”1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.