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Method 6010B (and draft 6010C) Both methods are broadly similar and provide guidelines on general laboratory practices such as sample preparation, instrument setup, calibration of analytes, and interference correction equations. They also provide specific rules on various analytical practices that must be followed, including elements covered, quality control practices and instrument validation. Since both methods are well established and readily available in the public domain they have become widely adopted as templates for methodologies used by a host of laboratories undertaking environmental analysis world-wide. The aim of the protocol is to ensure a consistently high quality of analytical data by enforcing compliance with a variety of stringent instrument and analytical performance checks. NOTE: Method 6010C, along with all Draft Update IVA SW-846 methods, may be downloaded from the EPA OSW website: http://www.epa.gov/epaoswer/hazwaste/test/up4a.htm 3. Experimental 3.1 Equipment An IRIS Intrepid II Model XDL ICP-AES (Thermo Electron Corporation, Franklin, Mass., USA) was used for the analysis of soil and sludge samples. It was fitted with a dual view optical design - axial view was used for elements expected at low concentration where the best sensitivity is required while radial view was used for elements at higher concentration or for those elements that suffer from EIE (Easily Ionised Element) interference. Internal standards were added on-line using the Internal Standard Mixing Kit (P/N 13670800). The instrument conditions used for the analysis are shown in Table 1 below. PARAMETER VALUE RF Forward power 1200 watts Torch Orientation Dual View Torch Gas Flow 16 L/min Auxiliary Gas Flow 0.5 L/min Mixing Chamber Glass Cyclone Nebulizer Glass Concentric Nebulizer Gas 0.65 L/min Sample Pump Winding 3-stop Orange Tygon Sample Uptake 1.7 mL/min Purge Gas Argon Tank Flow 4 L/min Nozzle Flow 4 L/min Camera Flow 1 L/min Table 1. Intrepid II XDL Parameters Details of the wavelengths and plasma view orientations used, as well as the internal standards employed, are shown in Table 2. ELEMENT WAVELENGTH PLASMA INTERNAL (nm) VIEW STANDARD Ag 328.289 Axial Y 361 Al 308.215 Radial Y360 As 189.042 Axial Y224 B 208.959 Axial Y224 Ba 455.403 Radial Y360 Be 313.107 Radial Y360 Ca 317.933 Radial Y360 Cd 214.438 Axial In230 Co 228.616 Axial In230 Cr 205.552 Axial Y224 Cu 324.754 Axial Y361 Fe 271.441 Radial Y360 In 230.606 Axial Int Std K 766.491 Radial Y360 Li 670.784 Radial Y360 Mg 279.079 Radial Y360 Mn 257.610 Axial Y361 Mo 202.030 Axial Y224 Na 589.592 Radial Y360 Ni 231.604 Axial In230 P 178.287 Axial In230 Pb 220.353 Axial In230 Sb 206.833 Axial Y224 Se 196.090 Axial Y224 Si 251.612 Radial Y360 Sn 189.989 Axial In230 Ti 334.941 Axial Y361 Tl 190.864 Axial In230 V 292.402 Axial Y361 Y 224.306 Axial Int Std Y 360.073 Radial Int Std Y 361.105 Axial Int Std Zn 206.200 Axial In230 Table 2. Wavelengths and Plasma View used. 3.2 Calibration Solutions Calibration Solutions High purity reagents were used throughout. Calibration standards were prepared in 5%v/v HCl and 1%v/v HNO3 from a range of SPEX ICP standards at concentrations selected to cover the linear range for each element. Mixed calibration standards were prepared according to the conditions laid down in Method 6010B. SOLUTION ELEMENTS I Be, Cd, Mn, Pb, Se and Zn II Ba, Co, Cu, Fe and V III As and Mo IV Al, Ca, Cr, K, Na, Ni, Li and Sr V Ag, Mg, Sb and Tl VI P A mixture of 20ppm In and 10ppm Y was used as the internal standard.
Blanks Two types of blanks are required for the analysis of samples prepared by any method other than EPA Method 3050B. The calibration blank is used in establishing the analytical curve and the method blank is used to identify possible contamination resulting from either the reagents (acids) or the equipment used during sample processing including filtration. The calibration blank is prepared by acidifying reagent water to the same concentrations of the acids found in the standards and samples. A sufficient quantity must be prepared to flush the system between standards and samples. The calibration blank will also be used for all initial (ICB) and continuing calibration blank (CCB) determinations. The method blank must contain all of the reagents in the same volumes as used in the processing of the samples. The method blank must be carried through the complete preparation procedure and contain the same acid concentration in the final solution as the sample solution used for analysis Check Solutions The initial calibration verification (ICV) standard is prepared by combining compatible elements from a standard source different from that used to prepare the calibration standard, and at concentration near the midpoint of the calibration curve. This standard may also be purchased commercially. The continuing calibration verification (CCV) standard is prepared in the same acid matrix using the same standards used for calibration, at a concentration near the mid-point of the calibration curve. The interference check solution (ICS) is prepared to contain known concentrations of interfering elements that will provide an adequate test of the correction factors. The sample is spiked with the elements of interest, particularly those with known interferences at the 0.5 to 1 mg/L level. 3.3 Method Development Interelement Corrections Due to the complex nature of the matrix experienced with these types of samples, significant interferences from spectral overlaps can be observed. As part of the method development process, high purity solutions of the major matrix elements, such as Al, Ca, Fe, Mg, Si and P, were checked for their contribution to the signals of other analyte elements. After the interfering elements were identified, their solutions were measured and the instrument software was used to automatically calculate the appropriate interference correction factors. Table 3 lists the major interferences found during this procedure. A dash indicates that no significant interference was encountered at the wavelength concerned. ELEMENT WAVELENGTH (nm) INTERFERING ELEMENT Ag 328.289 Ca, Fe Al 308.215 - As 189.042 - B 208.959 Al, Fe Ba 455.403 - Be 313.107 - Ca 315.887 - Cd 214.438 Fe Co 228.616 Fe Cr 205.552 Fe Cu 324.754 Ca, Fe Fe 271.441 - In 230.606 - K 766.491 - Li 670.784 - Mg 279.079 - Mn 257.610 Al, Mg Mo 202.030 - Na 589.592 - Ni 231.604 Al, Fe P 178.287 - Pb 220.353 Al, Fe Sb 206.833 Al, Fe Se 196.090 Al, Fe Si 251.612 - Sn 189.989 - Ti 334.941 - Tl 190.864 Mg V 292.402 Fe Y 224.306 - Y 360.073 - Y 361.105 - Zn 206.200 Fe, Mg Table 3. Interelement interferences. Method 6010B states that interference effects must be evaluated for each individual instrument and the interelement corrections should be verified daily by running an ICS. The measured values must be within 20% for five consecutive days. They must also be verified and updated every six months or when changes to the instrumentation have been made (i.e. changing torch or nebuliser or plasma conditions). Method Detection Limits (MDL) Method Detection Limits were established by measuring a solution containing all the analytes at concentration levels which are 3 - 5x the published Instrument Detection Limits for the IRIS Intrepid II. The solution was analysed ten times on three separate days and the mean of the three sigma values from all runs was calculated. Table 4 lists the MDL’s in mg/L measured in the test and Method 6010B calls for them to be re-confirmed on a quarterly basis.
Page 1: Application Note: AN_E0637 Key Word
Page 5 and 6: ELEMENT ICV (µg/g) CCV (µg/g) ACT
Page 7: Table 8 shows the results for a dup

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