1、October 2016 English price group 18No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 13.060.50!%nC“2577532www.din.deD
2、IN EN ISO 18635Water quality Determination of shortchain polychlorinated alkanes (SCCPs) in sediment,sewage sludge and suspended (particulate) matter Method using gas chromatographymass spectrometry (GCMS) and electron capture negative ionization (ECNI) (ISO 18635:2016);English version EN ISO 18635:
3、2016,English translation of DIN EN ISO 18635:2016-10Wasserbeschaffenheit Bestimmung kurzkettiger polychlorierter Alkane (SCCP) in Sediment, Klrschlamm und Schwebstoff Gaschromatographischmassenspektrometrisches Verfahren (GCMS) unter Anwendung negativer chemischer Ionisation und Elektroneneinfang (E
4、CNI) (ISO 18635:2016);Englische Fassung EN ISO 18635:2016,Englische bersetzung von DIN EN ISO 18635:2016-10Qualit de leau Dtermination des alcanes polychlors chane courte dans les sdiments et matires en suspension (particules) Mthode par chromatographie en phase gazeusespectromtrie de masse (CPGSM)
5、et ionisation chimique ngative (ICN) (ISO 18635:2016);Version anglaise EN ISO 18635:2016,Traduction anglaise de DIN EN ISO 18635:2016-10www.beuth.deDocument comprises 42 pagesDTranslation by DIN-Sprachendienst.In case of doubt, the German-language original shall be considered authoritative.10.16DIN
6、EN ISO 18635:2016-10 2 A comma is used as the decimal marker. National foreword This document (EN ISO 18635:2016) has been prepared by Technical Committee ISO/TC 147 “Water quality” in collaboration with Technical Committee CEN/TC 230 “Water analysis” (Secretariat: DIN, Germany). The responsible Ger
7、man body involved in its preparation was DIN-Normenausschuss Wasserwesen (DIN Standards Committee Water Practice), Working Committee NA 119-01-03 AA Wasseruntersuchung, Working Group 119-01-03-02-11 AK Chlorparaffine. Designation of the method: Determination of short-chain polychlorinated alkanes (S
8、CCPs) in sediment, sewage sludge and suspended (particulate) matter Method using gas chromatography-mass spectrometry (GC-MS) and electron capture negative ionization (ECNI) (H 48): Method DIN EN ISO 18635 H 48 The following changes have been made to the ISO Standard as regards application in German
9、y: In Clause B.3 “Multiple regression calibration for the sum of SCCPs”, with the help of, for example, Excel, the calculation with the LINEST function (RGP function) is easily possible. The DIN Standards corresponding to the International Standards referred to in this document are as follows: ISO 5
10、667-1 DIN EN ISO 5667-1 ISO 5667-12 DIN 38414-11 ISO 5667-13 DIN EN ISO 5667-13 ISO 5725-2 DIN ISO 5725-2 ISO 8466-1 DIN 38402-51 ISO 12010 DIN EN ISO 12010 DIN EN ISO 18635:2016-10 3 Expert assistance and specialized laboratories will be required to perform the analyses described in this standard.
11、Existing safety requirements are to be observed. Depending on the objective of the analysis, a check shall be made on a case-by-case basis as to whether and to what extent additional conditions will have to be specified. This standard has been prepared by DIN-Normenausschuss Wasserwesen (DIN Standar
12、ds Committee Water Practice) in collaboration with the Wasserchemische Gesellschaft - Fachgruppe in der Gesellschaft Deutscher Chemiker (Water Chemistry Society - Division of the German Chemical Society). It is part of the series Deutsche Einheitsverfahren zur Wasser-, Abwasser- und Schlammuntersuch
13、ung (German standard methods for the examination of water, waste water and sludge): Determination of short-chain polychlorinated alkanes (SCCPs) in sediment, sewage sludge and suspended (particulate) matter Method using gas chromatography-mass spectrometry (GC-MS) and electron capture negative ioniz
14、ation (ECNI) (H 48): Standard methods published as DIN Standards are obtainable from Beuth Verlag GmbH, either individually or grouped in volumes. The standard methods included in the loose-leaf publication entitled Deutsche Einheitsverfahren zur Wasser-, Abwasser- und Schlammuntersuchung will conti
15、nue to be published by Beuth Verlag GmbH and Wiley-VCH Verlag GmbH 410,9169; and 422,9355 (see Reference 6).Applying the entire procedure, a selection of chlorinated pollutants has been tested and found not to cause interferences below the concentrations given in Table 1.Table 1 Highest concentratio
16、n level which causes no interferences higher than the limit of quantification of 0,03 g/gPotential interfering compounds Highest concentration level which causes no interferences higher than the limit of quantification of 0,03 g/gAroclor 1262a0,25 g/gAroclor 1242a2 g/gAroclor 1221a2 g/gCampheclor (t
17、oxaphene) 0,35 g/gHalowax 1014a2 g/gHalowax 1051a0,08 g/gMCCP (medium-chain chlorinated n-alkanes) 42 % 2 g/gMCCP (medium-chain chlorinated n-alkanes) 52 % 1,2 g/gMCCP (medium-chain chlorinated n-alkanes) 57 % 2 g/gaAroclor 1262, Aroclor 1242, Aroclor 1221, Halowax 1014, and Halowax 1051 are product
18、s commercially available. This information is given for the convenience of users of this document and does not constitute an endorsement by ISO of these products.7EN ISO 18635:2016 (E) DIN EN ISO 18635:2016-10 5 Reagents Use solvents and reagents of sufficient purity, i.e. with negligibly low concen
19、trations of SCCPs, e.g. lower than the limit of detection of the method.Check blanks regularly over the entire procedure to establish proper analytical quality control.5.1 Solvents for extraction, column chromatography, and preparation of stock solutions.The solvent for extraction is n-heptane. Othe
20、r non-polar solvents, e.g. n-hexane (C6H14), cyclohexane (C6H12) can be used if the extraction efficiency is comparable with those of n-heptane.For conditioning of the clean-up columns, use mixtures of n-heptane and propanone (acetone) as described below.5.2 Reference SCCP stock solutions.Use commer
21、cially available solutions, e.g. in cyclohexane or n-hexane, of the single mixtures of SCCP congeners with defined carbon chain length and with different defined chlorine contents (see Table 2, first two columns). Alternatively, use commercially available ready mixed solutions with the same composit
22、ion.Mixtures of synthetic solutions are used to simulate environmentally occurring SCCPs or technical products of SCCPs. For example, the synthetic mixed calibration stock solution “Lake Ontario water” is mixed to resemble a Lake Ontario water as reported in Reference 5. Its characteristic is a rela
23、tively high content of C10to C12, especially C12and a low chlorine content as partly reported in water samples too. The synthetic mixed calibration stock solution “Perch” simulates a C-number distribution found in a perch (see Reference 6). The standard mixture “Sediment Drevnice” simulates a natura
24、l mixture reported about a sediment of the river Drevnice (see Reference 7) with a high content of C13and a higher chlorine content.The compositions of the calibration mixtures, as well as of the independent quality assurance solutions, are mandatory to achieve the quantification of the variety of S
25、CCP-mixtures. An example for recoveries of quality assurance solutions is given in Annex H.Prepare the solutions “Lake Ontario water”, “Perch”, and “Sediment Drevnice” according to Table 2.Table 2 Reference substances stock solutionsStandard solutions, e.g. in n-heptane Synthetic mixed standard solu
26、tions which resemble environmental mixturesn-alkane chain lengthChlorine content (%) of the individual C-number mixturesMean number of chlorines in the molecules (calculated)“Lake Ontario water”“Perch” “Sediment Drevnice”Chlorine content calculated (%) 50,2 60,6 65,0Composition, ng/mlC1044,82 3,22C1
27、050,18 3,97 1 000C1055,00 4,79 1 000C1060,09 5,86 500C1065,02 7,16 1 100 280C1145,50 3,63 1 000C1150,21 4,37 1 0008 EN ISO 18635:2016 (E) DIN EN ISO 18635:2016-10 Standard solutions, e.g. in n-heptane Synthetic mixed standard solutions which resemble environmental mixturesn-alkane chain lengthChlori
28、ne content (%) of the individual C-number mixturesMean number of chlorines in the molecules (calculated)“Lake Ontario water”“Perch” “Sediment Drevnice”Chlorine content calculated (%) 50,2 60,6 65,0Composition, ng/mlC1155,20 5,31 600C1160,53 6,55 1 000 500C1165,25 7,94 3 000 660C1245,32 3,93 2 000C12
29、50,18 4,76 2 000 800C1255,00 5,74 2 000 2 000C1265,08 8,59 900 1 000C1269,98 10,62 830C1344,90 4,19C1350,23 5,16C1355,03 6,22C1359,98 7, 56 100 730C1365,18 9,34 6 000Sum of SCCP (ng/ml) 10 000 10 000 10 000The chlorine content (third column) of the mixtures is calculated as the weighted mean.Store t
30、he prepared solutions in a refrigerator at 2 C to 6 C.5.3 Internal standard stock solutions from individual congeners.Use commercially available individual congener standard solutions and prepare a stock solution in propanone (acetone) (5.1) at a concentration of, for example, 1 g/ml. Individual SCC
31、P congeners with chlorine contents of between 50 % and 67 % are suitable as internal standards if the mass trace in mass spectrometric detection is not affected by matrix components, e.g. 1,1,1,3,11,13,13,13-octachlorotridecane at e.g. 0,1 g/ml.NOTE 1 The different individual SCCP congeners used as
32、internal standard substances probably contribute in environmental samples to the sum of SCCPs. Nevertheless, the contribution is approximately 50 % and no interfering peak should appear in the gas chromatogram. If necessary, GPC conditions need to be modified to meet these requirements.NOTE Alternat
33、ive clean-up procedures, an extended column chromatographic clean-up (see Annex D), and a modified gel chromatographic clean-up (see Annex E) can be used. The interferences quantified in Clause 4 apply only to the conditions described in this subclause.8.3 Measurement and integration of the chromato
34、gramOptimize the operating conditions of the GC-ECNI-MS system, e.g. according to the manufacturers instructions. Examples of the gas chromatographic conditions are given in Annex C.Prior to analysis, verify the performance of the GC-ECNI-MS system by analysis of calibration standards. Use, as a min
35、imum, the calibration solutions “Lake Ontario water” and “Sediment Drevnice” to optimize the GC-ECNI-MS system.Check the GC-ECNI-MS system performance regularly, e.g. between every 10 to 20 samples, by independently prepared calibration solutions (Table 3) with a concentration of, e.g. 1 g/ml sum of
36、 SCCP.The measurement is performed in the selected ion mode with four selected mass ion fragments (mass to charge values, m/z), i.e. m/z 375, m/z 411, and m/z 423, and m/z 449. For an explanation of this selection, see Reference 4.The integration of the different m/z values should be carried out wit
37、hin different time retention ranges that are established from calibration solutions. An example of the integration ranges dotted in Annex F is given in Table 4.Table 4 Typical retention time rangesm/z value Approximate retention time range Approximate retention time range of the response maximum ami
38、n min375 4,3 to 4,9 4,4 to 4,7411 4,5 to 5,0 4,7 to 4,9423 4,5 to 5,3 4,8 to 5,0449 4,8 to 5,7 5,0 to 5,5aThis represents the major portion of the SCCPs for the mass ion fragment monitored and is represented by an unresolved complex mixture of peaks.An example for integration of a real sample is giv
39、en in Annex I.Use selected ion mode measurements for detecting the internal standard. Integrate the response of the internal standard as a single peak with the following m/z values (see Table 5).Table 5 m/z values of internal standardInternal standard m/z for quantification m/z for qualification1,1,
40、1,3,11,13,13,13-Octachlorotridecane 460 4588.4 Calibration8.4.1 GeneralShort-chain polychlorinated n-alkanes with 50 % to 67 % chlorine content are mixtures containing approximately 6 000 congeners. SCCP compounds of different chlorine contents exhibit different 13EN ISO 18635:2016 (E) DIN EN ISO 18
41、635:2016-10 response factors in ECNI-MS. Interferences occur in the mass spectra because individual compounds cannot be separated by GC.Using multiple linear regression techniques quantification can be carried out to a large extent independent of chlorine content (see Annex B and Reference 4).While
42、modern mass spectrometric software frequently does not enable multiple linear regression techniques to be carried out, commercial software is available that does. See also the ready to use spreadsheet (http:/standards.iso.org/iso/18635/).8.4.2 Basic calibrationAnalyse the calibration solutions (5.4)
43、 and integrate the responses as described in 8.3. Calibration is carried out by multiple linear regression using Formula (1).SCCPsIS IS=+bAAAA1122b (1)or in case of calibration only with m/z 411SCCPsIS= bAA11whereSCCPsis the target concentration of the sum of SCCPs in the calibration solution, in mi
44、crograms per millilitre, g/ml;b1, b2are the regression coefficients, in micrograms per millilitre, g/ml;A1, A2are the peak areas of the analyte, e.g. m/z 375, m/z 423;AISis the peak area of the internal standard, e.g. m/z 460.The regression coefficients determined are used for quantification of unkn
45、own concentrations in samples. A graphical presentation of the three-dimensional calibration area is given in B.3.The graphical presentation of calculated against target sum concentrations of SCCPs is a suitable means for two-dimensional graphical assessment of the goodness of fit. A typical example
46、 is given in Annex G using 15 calibration solutions in Table 3.14 EN ISO 18635:2016 (E) DIN EN ISO 18635:2016-10 Table 6 Typical regression coefficients for the sum of SCCP with 50 % to 67 % chlorine content based on internal standardizationRegression coefficient with associated standard deviation (
47、in brackets) for the mass ion fragment combinationRegression coefficient with associated standard deviation (in brackets) for the mass ion fragment combinationRegression coefficient with associated standard deviation (in brackets) for the mass ion fragmentm/z 375 and m/z 423 m/z 411 and m/z 449 m/z
48、411Concentration range 0,15 g/ml to 3,0 g/ml, e.g. 0,03 g/g to 0,6 g/g with 15 calibration solutions, see Table 3m/z 375 m/z 411 m/z 4110,665 3 (0,027 5) 0,958 0 (0,129 6) 0,826 0 (0,096 5)m/z 423 m/z 4490,146 3 (0,012 13) 0,559 1 (0,316 7)Standard deviation of the predicted concentration0,216 0,416
49、 0,446Correlation coefficient 0,986 0,948 0,935The calibration can be checked with independent quality control mixtures of known concentrations of the sum of SCCPs. Any variation in the expected values should not exceed specified levels in 8.4.3. Typical examples are shown in Annex K (see also ISO 12010).Verify the limit of quantification and the limit of detection according to ISO/TS 13530. Use the graphical presentation of the goodness of fit (see Annex G) as a start-estimate of the concentration of th
