1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN 13804:2013Foodstuffs Determination of elements and their chemical species General considerations and specific r e q u i r e m e n t sBS EN 13804:2013 BRITISH STANDARDNation
2、al forewordThis British Standard is the UK implementation of EN 13804:2013. Itsupersedes BS EN 13804:2002 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee AW/275, Food analysis - Horizontal methods.A list of organizations represented on this committee ca
3、n beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2013. Published by BSI StandardsLimited 2013ISBN 978 0 580 76412 7ICS 67.050Compliance
4、with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 March 2013.Amendments issued since publicationDate Text affectedBS EN 13804:2013EUROPEAN STANDARD NORME EUROPENNE EUROPISCH
5、E NORM EN 13804 March 2013 ICS 67.050 Supersedes EN 13804:2002English Version Foodstuffs - Determination of elements and their chemical species - General considerations and specific requirements Produits alimentaires - Dtermination des lments et de leurs espces chimiques - Considrations gnrales et e
6、xigences spcifiques Lebensmittel - Bestimmung von Elementen und ihren Verbindungen - Allgemeines und spezielle Festlegungen This European Standard was approved by CEN on 12 January 2013. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for givi
7、ng 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-CENELEC Management Centre or to any CEN member. This European Standard exists in three offi
8、cial 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 same status as the official versions. CEN members are the national standards bodies of
9、 Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
10、Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2013 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN nation
11、al Members. Ref. No. EN 13804:2013: EBS EN 13804:2013EN 13804:2013 (E) 2 Contents Page Foreword . 3 Introduction 4 1 Scope 5 2 Sample preparation 5 3 Specific requirements for analysis of trace elements 9 4 Performance requirements and characteristics . 10 5 Interpretation and expression of results
12、. 13 6 Test report 14 Bibliography 15 BS EN 13804:2013EN 13804:2013 (E) 3 Foreword This document (EN 13804:2013) has been prepared by Technical Committee CEN/TC 275 “Food analysis - Horizontal methods”, the secretariat of which is held by DIN. This European Standard shall be given the status of a na
13、tional standard, either by publication of an identical text or by endorsement, at the latest by September 2013, and conflicting national standards shall be withdrawn at the latest by September 2013. Attention is drawn to the possibility that some of the elements of this document may be the subject o
14、f patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN 13804:2002. Compared to EN 13804:2002, the following changes were made: a) the Scope was updated; b) former Clause 3, “Terms and definitions“ was deleted; c) f
15、ormer Clause 4, “Performance characteristics“ was deleted; d) former Clause 5, “Sampling“ was deleted; e) former Clause 6, “Sample preparation“ was updated and wording is now more precise and appears in the new Clause 2; f) Subclause 2.3.2, “Storage for speciation purposes“ was added; g) Subclause 2
16、.4.2, Table 2 on “Examples of sample preparation procedures for some foodstuffs“ was thoroughly updated; h) Subclause 2.4.3, “Drying and lyophilisation“ was added; i) Former Subclause 7.1, “Reagents“ was revised and introduced in 3.1; j) Former Clause 8, “Laboratory Quality standards“ was completely
17、 revised and appears now as Clause 4, “Performance requirements and characteristics“; k) Former Clause 9, “Expression of results“ was revised and appears now as Clause 5, “Interpretation and expression of results“; l) Former Clause 10, “Test report“ was specified and appears now as Clause 6; m) the
18、Bibliographic references were completed; n) the whole document was editorially revised. According to the CEN/CENELEC Internal Regulations, the national standards organisations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech
19、 Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, 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.
20、 BS EN 13804:2013EN 13804:2013 (E) 4 Introduction The Working Group, CEN/TC 275/WG 10 “Elements and their chemical species“, selects and elaborates methods of analysis of elements and their chemical species in foodstuffs. There are many methods of analysis for the determination of elements in foodst
21、uffs which have been validated and published; the analyst is often required to make a choice between several established methods all of which purport to be applicable to the same analyte/matrix combination. The Working Group decided to establish specific criteria to guide the analyst in the selectio
22、n between several methods of analysis. As a general rule, analysts should give preference to methods of analysis which comply with the provisions given in Clauses 1 and 2 of the annex to 1, with the Decision in 2 and with the General Principles for Methods of Analysis of the Codex Alimentarius Commi
23、ssion (CAC), as defined in the CAC Procedural Manual and further developed in the ”criteria approach“ to methods of analysis developed by the Codex Committee of Methods of Analysis and Sampling (CCMAS). The performance criteria laid down in this European Standard are based on published data or colle
24、cted from official reports on European interlaboratory studies. When such performance characteristics are not available, the criteria were established based on the experience and opinions of the experts of CEN/TC 275/WG 10. The criteria included in this European Standard have also been used as guida
25、nce in the Working Group 10 for the selection of specific methods of analysis of trace elements to be standardised. In addition, the Working Group 10 also decided to provide some general information on sample handling and sample preparation, laboratory organisation and equipment. This document does
26、not deal with sampling issues. It provides an overview of the processes involved from receipt of the laboratory sample to the end result. General sample preparation procedures are specified, as well as examples for some foodstuffs. BS EN 13804:2013EN 13804:2013 (E) 5 1 Scope This European Standard s
27、pecifies performance criteria for the selection of methods of analysis of elements and their chemical species in foodstuffs and contains performance requirements and characteristics, guidelines for laboratory set-up, sample preparation and test reports. 2 Sample preparation 2.1 General Food samples
28、are commonly treated in the same way as is done before consumption (washed, peeled, removal of non-edible parts). Apart from the treatments that are just mentioned and that are clarified in some more detail in 2.4.1 and 2.4.2, samples should not undergo further processing (i.e. samples should not be
29、 boiled, steamed, fried, heated or the like). Extra treatments, like drying, may be performed to prevent the sample from decaying. In particular, for speciation analyses, the potential loss or change of analytes shall be considered carefully though. Finally the sample needs to be homogenised (for ex
30、ample by grinding) to obtain a homogenous test portion. Contamination and uncontrolled loss of liquid, e.g. during operations such as grinding and cutting, shall be avoided to the greatest extent possible. 2.2 Reagents, apparatus and equipment No reagents and chemicals other than water shall be used
31、 in sample preparation. Water with the quality of drinking water may be used for washing some samples, e.g. vegetables. However, depending on the purpose of the analysis and the element to be determined, it may be necessary to use purified water (see 3.1). Apparatuses and equipment should preferably
32、 be designated for trace element analysis. Typical kitchen utensils (e.g. plastic dishes, plastic salad spinner, and coffee grinder) may also be used for sample preparation steps as long as they do not affect both the sample and the elements to be determined. Any equipment coming into direct contact
33、 with the sample shall, if necessary, be cleaned with detergent and hot water. Equipment cleaned with detergent, and containers for storage of homogenised samples, should be treated with diluted nitric acid (approximately 6 % by volume) followed by purified water, if appropriate. Contamination probl
34、ems may arise when stainless steel or iron equipment is used for analysis of elements such as chromium, molybdenum, nickel and iron. Special apparatus shall be used in such cases, e.g. titanium or ceramic knives, agate mortar or ball mill for size reduction and homogenisation. Ceramic materials show
35、 a high degree of mechanical and chemical stability, but they might have varying compositions (e.g. Al-oxides, Zr-oxides). Homogenisers shall be chosen carefully as not to cause losses of volatile elements (e.g. by heating up the sample during mixing) or to cause contamination of the elements to be
36、determined or modification of species (e.g. due to warm-up by friction) in the case of speciation analyses. 2.3 Storage 2.3.1 General Both laboratory samples and test samples shall be stored in such a way that the composition and sample mass does not change as a result of, for instance, drying out,
37、evaporative loss, spoilage or decay. The test sample should be prepared as quickly as possible after arrival of the laboratory sample. Test samples may be stored in a refrigerator or frozen depending on the nature of the material and the expected storage time. Suitable storage material may be made o
38、f glass, plastic containers closed with a screw cap or plastic bags. Dry products may be stored at room temperature. BS EN 13804:2013EN 13804:2013 (E) 6 2.3.2 Storage for speciation purposes Some considerations shall be kept in mind when storing samples for speciation purposes. Parameters with a str
39、ong influence in speciation analysis are (see Table 1): a) Temperature: Storage temperature shall be low enough to prevent microbial activity resulting in reactions, e.g. methylation and biodegradation (see Table 1). b) pH: The pH of the media may strongly affect the stability of the inorganic speci
40、es. Samples intended for species analysis shall not be changed in their acidity for preservation purposes. c) Light: Light may cause instability of organometallic compounds by photodegrading. When analysing organometallic compounds storage shall be done in dark or in opaque containers. d) Storage ti
41、me: Generally, storage should be kept as short as possible. Table 1 Examples of storage conditions for samples intended for speciation purposes Element (species) Storage conditions Hg (Hg(II), methylmercury) Keep samples at 4 C or lower in darkness. Dilution shall be done only immediately before the
42、 analysis. Sn (butylated organotin compounds) PVC containers shall not be used to avoid contamination by organotin compounds. Store samples in borosilicate glass bottles in the dark, at least at 4 C or lower. Cr (Cr (III) and Cr (VI) Only borosilicate or quartz glass should be used for handling and
43、storage. Some glassware may cause contamination with chromium. Keep samples at 4 C or lower. The pH has different effect on the stability of Cr (III) and Cr (VI). Se (Se (IV), Se (VI) and methylated compounds) Avoid the use of poly tetra fluoro ethylene containers 3. Keep at -20 C or lower to avoid
44、any change of the inorganic species. Acid media (pH 1,5 to 2) avoid oxidation of Se (IV) to Se (VI). As (As (III), As (V), and organic As-species) Keep samples at 4 C or lower, in darkness. Avoid the use of glassware as this may cause contamination with arsenate. 2.4 Procedures for sample preparatio
45、n 2.4.1 General For some trace elements sampling preparation procedures are laid down in EU legislation. Commission Regulation (EC) No 1881/2006 4 defines the foodstuffs to which the EU maximum levels apply. Further sample preparation methods for official control of the levels of these elements are
46、laid down in Regulation (EC) No 333/2007 5. Other specific legislation may also apply to trace elements. Without prejudice to the specific provisions of EU legislation for official control, in food analysis only the edible part should be investigated and the results should refer to this part. Parts
47、which are usually not intended for consumption should be removed, e.g. outer leaves, shell, skin and bones. Surface contamination like soil should be thoroughly removed by rinsing with drinking water or purified water. For preparation of the test portion a sufficient and representative amount should
48、 be available from the edible part of the laboratory sample. Please note that the edible part can differ between countries. The prepared and analysed part of the test portion has to be described in the test report (e.g. potatoes peeled or potatoes washed and unpeeled). Rinse samples with water befor
49、e cutting to avoid leaching from cut surfaces. After rinsing with drinking water samples shall be rinsed with purified water. Excess water should be physically removed, e.g. by shaking, using a sieve or a strainer (e.g. for leafy vegetables). Removing excess water by wiping with a soft tissue paper can cause random sample contamination and should not be used for elemental trace analysis. The washing step can be omitted for samples designated as “ready to eat”. BS EN 13804:2013EN 13804:2013 (E) 7 2.4.2 Examples of sample preparation for some foodstuffs T