DIN EN 16802-2016 Foodstuffs - Determination of elements and their chemical species - Determination of inorganic arsenic in foodstuffs of marine and plant origin by anion-exchange .pdf

1、July 2016 English price group 10No 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 67.050; 67.060; 67.120.30!%XLU“2534

2、150www.din.deDIN EN 16802Foodstuffs Determination of elements and their chemical species Determination of inorganic arsenic in foodstuffs of marine and plant origin by anion-exchange HPLC-ICP-MS;English version EN 16802:2016,English translation of DIN EN 16802:2016-07Lebensmittel Bestimmung von Elem

3、enten und ihren Verbindungen Bestimmung von anorganischem Arsen in Lebensmitteln marinen Ursprungs und pflanzlichenLebensmitteln mit Anionenaustausch-HPLC-ICP-MS;Englische Fassung EN 16802:2016,Englische bersetzung von DIN EN 16802:2016-07Produits alimentaires Dtermination des lments et de leurs esp

4、ces chimiques Dtermination de la teneur en arsenic inorganique dans les produits alimentaires dorigines marine et vgtale, par CLHP avec change danions et spectromtrie de masse plasma induit par haute frquence (ICP-SM);Version anglaise EN 16802:2016,Traduction anglaise de DIN EN 16802:2016-07www.beut

5、h.deDTranslation by DIN-Sprachendienst.In case of doubt, the German-language original shall be considered authoritative.Document comprises 15 pages 06.16 DIN EN 16802:2016-07 2 A comma is used as the decimal marker. National foreword This document (EN 16802:2016) has been prepared by Technical Commi

6、ttee CEN/TC 275 “Food analysis Horizontal methods” (Secretariat: DIN, Germany). The responsible German body involved in its preparation was DIN-Normenausschuss Lebensmittel und landwirtschaftliche Produkte (DIN Standards Committee Food and Agricultural Products), Working Committee NA 057-01-09 AA El

7、emente und ihre Verbindungen. The DIN Standards corresponding to the International Standards referred to in this document are as follows, whereby EN ISO Standards are only listed below if these have not been published as DIN EN ISO Standards with the same number: EN ISO 3696 DIN ISO 3696 ISO 5725-2

8、DIN ISO 5725-2 National Annex NA (informative) Bibliography DIN ISO 3696, Water for analytical laboratory use Specification and test methods DIN ISO 5725-2, Accuracy (trueness and precision) of measurement methods and results Part 2: Basic method for the determination of repeatability and reproducib

9、ility of a standard measurement method EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 16802 March 2016 ICS 67.050; 67.060; 67.120.30 English Version Foodstuffs - Determination of elements and their chemical species - Determination of inorganic arsenic in foodstuffs of marine and plant origin b

10、y anion-exchange HPLC-ICP-MS Produits alimentaires - Dtermination des lments et de leurs espces chimiques - Dtermination de la teneur en arsenic inorganique dans les produits alimentaires dorigines marine et vgtale, par CLHP avec change danions et spectromtrie de masse plasma induit par haute frquen

11、ce (ICP-SM) Lebensmittel - Bestimmung von Elementen und ihren Verbindungen - Bestimmung von anorganischem Arsen in Lebensmitteln marinen Ursprungs und pflanzlichen Lebensmitteln mit Anionenaustausch-HPLC-ICP-MS This European Standard was approved by CEN on 8 February 2016. CEN members are bound to c

12、omply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENE

13、LEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the

14、 same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembo

15、urg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels

16、 2016 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 16802:2016 EEN 16802:2016 (E) 2 Contents Page European foreword . 3 1 Scope 4 2 Normative references 4 3 Principle . 4 4 Reagents . 4 5 Apparatus and equipment . 6 6 Procedure.

17、7 6.1 General 7 6.2 Waterbath extraction 7 6.3 Determination of inorganic arsenic by HPLC-ICP-MS 7 6.3.1 Preparation of HPLC-ICP-MS for analysis . 7 6.3.2 Calibration . 8 6.3.3 Determination of samples and blank solution . 8 6.3.4 HPLC sequence . 8 6.3.5 Typical HPLC-ICP-MS settings . 8 6.4 Quality

18、control . 9 7 Calculation . 9 7.1 Integration of peaks . 9 7.2 Inorganic arsenic in test solutions 9 7.3 Calculation of inorganic arsenic in the samples 9 8 Precision 10 8.1 General . 10 8.2 Repeatability 10 8.3 Reproducibility . 10 9 Test report 10 Annex A (informative) Precision data . 11 Annex B

19、(informative) Supplementary information about chromatographic conditions 12 Bibliography . 13 DIN EN 16802:2016-07 EN 16802:2016 (E) 3 European foreword This document (EN 16802:2016) has been prepared by Technical Committee CEN/TC 275 “Food analysis - Horizontal methods”, the secretariat of which is

20、 held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by September 2016, and conflicting national standards shall be withdrawn at the latest by September 2016. Attention is drawn to the possi

21、bility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document has been prepared under mandate M 422 given to CEN by the European Commission and the European Free Tra

22、de Association. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedo

23、nia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. DIN EN 16802:2016-07 EN 16802:2016 (E) 4 1 Scope This European Standard

24、 describes a procedure for the determination of inorganic arsenic in foodstuffs of marine and plant origin by anion-exchange HPLC-ICP-MS following waterbath extraction. This method has been validated in an interlaboratory test on white rice, wholemeal rice, leek, blue mussels, fish muscle and seawee

25、d with an inorganic arsenic mass fraction in the range 0,073 mg/kg to 10,3 mg/kg 1. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For un

26、dated references, the latest edition of the referenced document (including any amendments) applies. EN 13804, Foodstuffs Determination of elements and their chemical species General considerations and specific requirements EN ISO 3696, Water for analytical laboratory use Specification and test metho

27、ds (ISO 3696) 3 Principle This standard describes a method for the determination of inorganic arsenic. Inorganic arsenic consists of arsenite, As(III) and arsenate, As(V). A representative test portion of the sample is treated with a diluted nitric acid and hydrogen peroxide solution in a heated wat

28、erbath. Hereby the arsenic species are extracted into solution and As(III) is oxidized to As(V). The inorganic arsenic is selectively separated from other arsenic compounds using anion exchange HPLC (High Performance Liquid Chromatography) coupled online to the element-specific detector ICP-MS (Indu

29、ctively Coupled Plasma Mass Spectrometry) for the determination of the mass fraction of inorganic arsenic. External calibration with solvent matrix-matched standards is used for quantification of the amount of inorganic arsenic. WARNING The use of this standard can involve hazardous materials, opera

30、tions and equipment. This standard does not purport to address all the safety problems 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 its use. 4 Rea

31、gents 4.1 General The concentration of the arsenic species in the reagents and water used shall be low enough to not affect the results of the determination. When using a method of high sensitivity like ICP-MS, the control of the blank levels of water, acid and other reagents is very important. Gene

32、rally ultra-pure water complying with ISO 3696 grade 1 (i.e. electrical conductivity below 0,1 S/cm at 25 C) and acid of high purity, e.g. cleaned by sub-boiling distillation, are recommended. Reagents should be of minimum p.a. quality where possible. Special facilities can be used in order to avoid

33、 contamination during the steps of preparation and measurement (e.g. uses of laminar flow benches or comparable clean room facilities). 4.2 Nitric acid concentrated, mass fraction w(HNO3), 65 %, mass concentration of approximately (HNO3) = 1,4 g/ml. Use only nitric acid available with high purity or

34、 perform a clean-up by a sub-boiling distillation in order to avoid potential contamination. DIN EN 16802:2016-07 EN 16802:2016 (E) 5 4.3 Hydrogen peroxide, w(H2O2) 30 %. High purity is essential to avoid potential contamination. Commercially available hydrogen peroxide for analysis should be tested

35、 for contamination of arsenic. 4.4 Extraction solution 1, c(HNO3) = 0,1 mol/l in 3 %(V/V) H2O2.Pour 800 ml of H2O and then 6,5 ml of HNO3(4.2) and thereafter 100 ml of H2O2(4.3) into a 1 000 ml volumetric flask. Fill it up to the mark with H2O. This solution should be prepared on the same day of use

36、. It is recommended that the total volume needed for the analysis is estimated and only this amount is produced. 4.5 Extraction solution 2, c(HNO3) = 0,2 mol/l in 6 % (V/V) H2O2.Pour 70 ml of H2O, 1,3 ml of nitric acid (4.2) and 20 ml of hydrogen peroxoide (4.3) into a 100 ml volumetric flask. Fill

37、up to the mark at 100 ml with H2O. This solution should be prepared on the same day of use. It is recommended that the total volume needed for the analysis is estimated and only this amount is produced. 4.6 Ammonium carbonate, w(NH4)2CO3 99,999 %, for production of mobile phase solution. 4.7 Aqueous

38、 ammonia, wNH3(aq.) 25 %, for adjustment of pH in the mobile phase. 4.8 Methanol, (CH3OH), HPLC grade, for production of mobile phase. 4.9 Mobile phase, e.g. 50 mmol/l ammonium carbonate in 3 % methanol at pH 10,3. Dissolve e.g. 4,80 g of ammonium carbonate (4.6) in approximately 800 ml of water. Ad

39、just the pH to 10,3 with aqueous ammonia (4.7), add 30 ml of methanol (4.8) and fill up to 1 000 ml with water. Filter the mobile phase solution through a 0,45 m filter prior to use. The optimal concentration of ammonium carbonate in the mobile phase depends on the analytical column used (e.g. brand

40、, particle size and dimensions). The appropriate concentration of ammonia carbonate is at the discretion of the analyst and should fulfil the criteria for sufficient resolution of the arsenate peak as stated in 5.10. Methanol is added to the mobile phase in order to enhance the signal intensity for

41、arsenic (carbon enhancement effect 2). The concentration of methanol for maximum signal depends on the instrument used and should be identified by the analyst. 4.10 Diarsenic trioxide, w(As2O3) 99,5 %, optional. 4.11 Potassium hydroxide solution, (KOH) = 20 g/100 ml, optional. 4.12 Sulfuric acid sol

42、utions, w(H2SO4) = 20 % and w(H2SO4) = 1 %, optional. 4.13 Phenolphthalein, optional. 4.14 Standard solutions, with an arsenic mass concentration of 1 000 mg/l. The use of commercial standards of arsenic, arsenic III and/or V, with a mass concentration of 1 000 mg/l is recommended. DIN EN 16802:2016

43、-07 EN 16802:2016 (E) 6 Otherwise proceed as follows: Dissolve e.g. 1,320 g of diarsenic trioxide (4.10) in 25 ml of potassium hydroxide solution (4.11), neutralize with 20 % sulfuric acid solution (4.12) with phenolphthalein (4.13) as indicator and dilute to 1 000 ml in a volumetric flask with 1 %

44、sulfuric acid solution (4.12). NOTE By preparing the standard in the extraction solution 1 (4.4) all arsenite will be completely oxidized to arsenate. 4.15 Calibration solutions. Prepare a range of standards including a blank calibration solution that covers the linear range of the analyte to be det

45、ermined by diluting the analyte stock solution with extraction solution 1 (4.4). Appropriate matrix matching of the calibration solutions shall be performed by using the extraction solution 1 (4.4) for the final dilution step, which furthermore will prevent reduction of arsenate to arsenite. Transfe

46、r an aliquot of the calibration solutions to HPLC vials prior to analysis (6.3.2). The quantitative oxidation of arsenite to arsenate in the standard solutions should be verified (e.g. visual inspection of chromatogram by looking for an additional peak or a reduced intensity of the arsenate peak). 4

47、.16 Solution for checking chromatographic separation, containing the organic arsenic compounds (e.g. 10 g/l) monomethylarsenous acid (MMA), dimethylarsinic acid (DMA) and arsenobetaine (AB), as well as arsenate (e.g. 10 g/l) and chloride (e.g. 100 mg/l). 5 Apparatus and equipment 5.1 General To mini

48、mize the contamination, all apparatus and equipment that come into direct contact with the sample and the solutions shall be carefully pre-treated. It is recommended to avoid the use of glassware, since this may cause contamination with arsenate, see 3. WARNING Some autosampler systems use syringes

49、made of glass. In this case, it is only possible to check for contamination and to minimize it. 5.2 Laboratory grinder, capable of grinding to a particle size of less than 0,5 mm. 5.3 Analytical balance, accuracy of 1 mg. 5.4 Filtering device, for filtration of mobile phase, maximum pore size 0,45 m. 5.5 Waterbath, adjustable to 90 C. 5.6 Centrifuge, minimum 2 010 g (4 000 min-1). 5.7 Single use syringe filters (0,45 m) or