usepa-6020b-2014(代替usepa6020a-2007)電感耦合等離子體質(zhì)譜法

1、 SW-846 Update V 6020B - 1 Revision 2 July 2014 METHOD 6020B INDUCTIVELY COUPLED PLASMA—MASS SPECTROMETRY SW-846 is not intended to be an analytical training manual. Therefore, method proce

2、dures are written based on the assumption that they will be performed by analysts who are formally trained in at least the basic principles of chemical analysis and in the use of the subject technology. In addition, SW

3、-846 methods, with the exception of required method use for the analysis of method-defined parameters, are intended to be guidance methods which contain general information on how to perform an analytical procedure or

4、technique which a laboratory can use as a basic starting point for generating its own detailed standard operating procedure (SOP), either for its own general use or for a specific project application. The performance

5、data included in this method are for guidance purposes only, and are not intended to be and must not be used as absolute quality control (QC) acceptance criteria for purposes of laboratory accreditation. 1.0 SCOPE AN

6、D APPLICATION 1.1 Inductively coupled plasma-mass spectrometry (ICP-MS) is applicable to the determination of sub-µg/L concentrations of a large number of elements in water samples and in waste extracts or diges

7、ts (Refs. 1 and 2). When dissolved constituents are required, samples must be filtered and acid-preserved prior to analysis. No digestion is required prior to analysis for dissolved elements in water samples. Acid d

8、igestion prior to filtration and analysis is required for groundwater, aqueous samples, industrial wastes, soils, sludges, sediments, and other solid wastes for which total (acid-leachable) elements are required. The

9、analyst should insure that a sample digestion method is chosen that is appropriate for each analyte and the intended use of the data. Refer to Chapter Three for the appropriate digestion procedures. 1.2 ICP-MS has bee

10、n applied to the determination of over 60 elements in various matrices. Analytes for which the acceptability of Method 6020 has been demonstrated through multi-laboratory testing on solid and aqueous wastes are listed

11、 below. Element Symbol CASRNa Element Symbol CASRNa Aluminum Al 7429-90-5 Magnesium Mg 7439-95-4 Antimony Sb 7440-36-0 Manganese Mn 7439-96-5 Arsenic As 7440-38-2 Mercury Hg 7439-97-6 Barium Ba 7440-39-3 Nickel Ni 744

12、0-02-0 Beryllium Be 7440-41-7 Potassium K 7440-09-7 SW-846 Update V 6020B - 3 Revision 2 July 2014 interference from lithium native to the sample is minimized. Other elements may need to be

13、used as internal standards when samples contain significant native amounts of the recommended internal standards as indicated by high bias of internal standard recoveries. Note: Other potential causes of a high bias sho

14、uld also be considered before a final decision is made that the internal standard high bias is caused by an excessive concentration of the internal standard isotope in the sample. 1.6 Prior to employing this method,

15、analysts are advised to consult the preparatory method for each type of procedure that may be employed in the overall analysis (e.g., Methods 3005, 3010, 3015, 3031, 3040, 3050, 3051, 3052, 7000, and 6800) for addition

16、al information on QC procedures, development of QC acceptance criteria, calculations, and general guidance. Analysts also should consult the disclaimer statement at the front of the manual and the information in Chap

17、ter Two for guidance on the intended flexibility in the choice of methods, apparatus, materials, reagents, and supplies, and on the responsibilities of the analyst for demonstrating that the techniques employed are app

18、ropriate for the analytes of interest, in the matrix of interest, and at the levels of concern. In addition, analysts and data users are advised that, except where explicitly specified in a regulation, the use of SW-

19、846 methods is not mandatory in response to Federal testing requirements. The information contained in this method is provided by EPA as guidance to be used by the analyst and the regulated community in making judgmen

20、ts necessary to generate results that meet the data quality objectives (DQOs) for the intended application. 1.7 This method is restricted to use by, or under supervision of, properly experienced and trained personnel.

21、 Each analyst must demonstrate the ability to generate acceptable results with this method. 2.0 SUMMARY OF METHOD 2.1 Prior to analysis, aqueous and solid samples are solubilized or digested using the appropriate sa

22、mple preparation methods (see Chapter Three). When analyzing groundwater samples for dissolved constituents, acid digestion is not necessary, if the samples are filtered and acid-preserved prior to analysis (e.g., Met

23、hods 3005, 3010, 3015, 3031, 3050, 3051 and 3052). For oils, greases, or waxes, use the solvent dissolution procedure in method 3040 to prepare the samples. 2.2 This method describes multi-element determinations using

24、 ICP-MS in environmental samples. The method measures ions produced by a radio-frequency inductively coupled plasma. Analyte species in liquid are nebulized and the resulting aerosol is transported by argon gas into

25、 the plasma torch. The ions produced by high temperatures are entrained in the plasma gas and introduced, by means of an interface, into a mass spectrometer. The ions produced in the plasma are sorted according to th

26、eir mass-to-charge (m/z) ratios and quantified with a channel electron multiplier. Interferences must be assessed and valid corrections applied or the data flagged to indicate problems. Interference correction must i