【国外标准】 Standard Test Methods for Manganese in Water

4.1 Elemental constituents in potable water, receiving water, and wastewater need to be identified for support of effective pollution control programs. Test Methods A, B, and C provide the techniques necessary to make such measurements.4.2 Although inhaled manganese dusts have been reported to be toxic to humans, manganese normally is ingested as a trace nutrient in both food and water. Because it is considered to be relatively nontoxic to man, as well as aquatic life, a limit of 50 μg/L has been established in the EPA National Secondary Drinking Water Regulations. This limit is based primarily on its ability to stain laundry and produce objectionable tastes in beverages.4.3 Manganese does not occur naturally as a metal but is found in various salts and minerals, frequently in association with iron compounds. Manganese is not mined in the United States except when manganese is contained in iron ores that are deliberately used to form ferro-manganese alloys. Manganese salts are used as fertilizer additives and are commonly found in surface and ground waters.4.4 ICP-MS or ICP-AES may also be appropriate but at a higher instrument cost. See Test Methods D5673 and D1976.1.1 These test methods cover the atomic absorption determination of dissolved and total recoverable manganese in water and certain wastewaters. Section 34 on Quality Control pertains to these test methods. Three test methods are given as follows:Test Method Concentration Range SectionsA—Atomic Absorption, Direct 0.1 to 5 mg/L 7 to 15B—Atomic Absorption, Chelation-Extraction 10 to 500 μg/L 16 to 24C—Atomic Absorption, Graphite Furnace 5 to 50 μg/L 25 to 331.2 Test Methods A, B, and C were used successfully on reagent grade and natural waters. Other matrices used in the study were brine (Test Method B), effluent from a wood treatment plant, and condensate from a medium BTU coal gasification process (Test Method C). It is the user's responsibility to ensure the validity of a test method for waters of untested matrices.1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversion to inch-pound units that are provided for information only and are not considered standard.1.4  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 and health practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see 11.7, 20.2, 20.9, and 22.11.1.5 Former Test Method A (Colorimetric) was discontinued. For historical information, see Appendix X1.1.6 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.