1、 DEUTSCHE NORMJune 2006DIN EN 15137 ICS 67.250; 71.040.40 Materials and articles in contact with foodstuffs Certain epoxy derivates subject to limitation Determination of NOGE and its hydroxy and chlorinated derivatives English version of DIN EN 15137:2006-06 Werkstoffe und Gegenstnde in Kontakt mit
2、 Lebensmitteln Bestimmte Epoxyderivate, die Beschrnkungen unterliegen Bestimmung von NOGE und dessen Hydroxy- und Chlorderivaten Englische Fassung DIN EN 15137:2006-06 Document comprises 26 pages No part of this standard may be reproduced without prior permission of DIN Deutsches Institut fr Normung
3、 e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany, has the exclusive right of sale for German Standards (DIN-Normen). English price group 13 www.din.de www.beuth.de !,o-X“10.06 9761053DIN EN 15137:2006-06 2 National foreword This standard has been prepared by CEN/TC 194 Utensils in contact wi
4、th food (Secretariat: United Kingdom). The responsible German body involved in its preparation was the Normenausschuss Materialprfung (Materials Testing Standards Committee), Technical Committee NMP 893 Bedarfsgegenstnde aus Kunststoff in Kontakt mit Lebensmitteln Prfung der Migration aus Kunststoff
5、en. EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 15137March 2006ICS 67.250; 71.040.40English VersionMaterials and articles in contact with foodstuffs - Certain epoxyderivatives subject to limitation - Determination of NOGE and itshydroxy and chlorinated derivativesMatriaux et objets en contact
6、avec des denresalimentaires - Drivs poxy soumis des limitations -Dtermination des NOGE et de leurs drivs hydroxyls etchlorsWerkstoffe und Gegenstnde in Kontakt mit Lebensmitteln- Bestimmte Epoxyderivate, die Beschrnkungenunterliegen - Bestimmung von NOGE und dessen Hydroxy-und ChlorderivatenThis Eur
7、opean Standard was approved by CEN on 23 January 2006.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references co
8、ncerning such nationalstandards may be obtained on application to the Central Secretariat or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own
9、language and notified to the Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg,
10、Malta, Netherlands, Norway, Poland, Portugal, Romania,Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2006 CEN All rights of expl
11、oitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 15137:2006: EEN 15137:2006 (E) 2 Contents Page Foreword .3 Introduction.4 1 Scope5 2 Normative references5 3 Principle .5 4 Reagents 6 5 Apparatus.8 6 Samples9 7 Procedure.11 8 Precision 14 9 Confirmation 14
12、 10 Test report15 Annex A (informative) The 7 positional 3-ring NOGE isomers.16 Annex B (informative) Substances that may occur in an HPLC chromatogram of a can coating .18 Annex C (informative) Principle of the determination of the content of NOGE and its hydroxy and chlorinated derivatives in can
13、coatings20 Annex D (informative) Typical chromatogram of NOGE standard, before and after hydrolysis 21 Annex ZA (informative) Relationship between this European Standard and the Essential Requirements of EU Directives.23 Bibliography24 EN 15137:2006 (E) 3 Foreword This document (EN 15137:2006) has b
14、een prepared by Technical Committee CEN/TC 194 “Utensils in contact with food”, the secretariat of which is held by BSI. 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 2006, and conflic
15、ting national standards shall be withdrawn at the latest by September 2006. This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association, and supports essential requirements of EU Directive(s). For relationship with EU Directive(s),
16、see informative Annex ZA, which is an integral part of this document. This document should be read in conjunction with EN 13130-1. WARNING: All chemicals are hazardous to health to a greater or lesser extent. It is beyond the scope of this European standard to give instructions for the safe handling
17、 of all chemicals, that meet, in full, the legal obligations in all countries in which this European standard may be followed. Therefore, specific warnings are not given and users of this European standard should ensure that they meet all the necessary safety requirements in their own country. Accor
18、ding to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuan
19、ia, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EN 15137:2006 (E) 4 Introduction NOGE (Novolac glycidyl ethers) is used as a monomer in the manufacture of certain polymeric food contact materials and articles.
20、The main application of NOGE is in epoxy coatings for cans and ends. The substance may also be used in organosol coatings. After the manufacture, residues of NOGE or its reaction products can remain in the finished product and may migrate into foodstuffs coming into contact with that product. The an
21、alytical method described allows for the determination NOGE and its reaction products in can coatings. EN 15137:2006 (E) 5 1 Scope This European standard describes the determination of NOGE components with more than two aromatic rings (the two-ring NOGE is equal to BFDGE = Bis(2-hydroxyphenyl)methan
22、e bis(2,3-epoxypropyl)ether) and at least one epoxy group as well as their derivatives containing chlorohydrin functions and having a molecular mass less than 1000 Daltons in can coatings. A high performance liquid chromatography (HPLC) method is employed based on reversed phase HPLC and fluorescenc
23、e detection. The method is capable of determining NOGE and its derivatives at a minimum level of 1 g/ml in solution. Direct HPLC analysis of the can coating extract may result in chromatograms difficult to interpret, due to interference from other components or the instability of the monomer resulti
24、ng in a complex mixture of derivatives and/or reaction products. By forced hydrolysis of all epoxy groups and their reaction products, the quantification of the NOGE is simplified and the identities of the substances are indicatively confirmed. NOTE In this European standard the term “NOGE and its d
25、erivatives” refers to the requirements of Directive 2002/16/EC 1 and its amendment, Directive 2004/13/EC 2. This includes NOGE components with more than two aromatic rings and at least one epoxy group as well as their derivatives containing chlorohydrin functions and having a molecular mass less tha
26、n 1000 Daltons. 2 Normative references The following referenced documents are indispensable for the application of this European standard. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. E
27、N 13130-1:2004, Materials and articles in contact with foodstuffs Plastics substances subject to limitation Part 1: Guide to the test methods for the specific migration of substances from plastics to foods and food simulants and the determination of substances in plastics and the selection of condit
28、ions of exposure to food simulants 3 Principle 3.1 Determination of NOGE and derivatives in a can coating Can coatings are extracted with acetonitrile for 24 h at room temperature. Then the extraction solvent is injected into a reverse phase HPLC column. The substances are separated using a gradient
29、 elution profile. Detection is performed by means of fluorescence detection. Identification is based on retention time and comparison with reference substances, fluorescence and UV detection response. For confirmation and quantification of NOGE and derivatives the epoxy and the chlorohydrin containi
30、ng components are fully hydrolysed in alkaline medium at elevated temperature to form the diol components. The hydrolysed components (NOGE per H2O) are separated by HPLC using fluorescence detection. The NOGE per H2O components will appear early in the chromatogram due to the increased polarity of t
31、he hydrolysed components. Compared to the HPLC chromatogram prior to hydrolysis a simpler HPLC chromatogram is obtained after hydrolysis, containing fewer peaks because all epoxy components and chlorohydrin derivatives disappear; if a peak remains then this substance shall be considered an interferi
32、ng substance originating from the matrix. To establish compliance with the restrictions set the total amount of diol substances is determined. If relevant, the total amount of NOGE per H2O derivatives is reduced with the amount of NOGE per H2O derivatives present initially, prior to hydrolysis. EN 1
33、5137:2006 (E) 6 3.2 Hydrolysis NOGE and its partly hydrolysed adducts hydrolyse in aqueous neutral and acid conditions. The chlorinated adducts are stable in acid conditions and hydrolyse only slowly in neutral aqueous media. However, in slightly alkaline conditions all adducts (excepting ether deri
34、vatives) hydrolyse to the NOGE per H2O components. To force complete hydrolysis of the epoxy and HCl adducts, the sample solutions are buffered at pH 8.5 and subsequently stored for a minimum of 20 h at 100 C. After that period the NOGE per H2O substances are determined. NOTE 1 Some structures of NO
35、GE and derivatives are shown in Annex A and B. NOTE 2 A flow chart showing the principle of the determination of NOGE and derivatives in can coatings is given in Annex C. 4 Reagents 4.1 Analytes 4.1.1 Poly(phenyl glycidyl ether)-co-formaldehyde CAS no 28064-14-4 The analyte substance contains approx
36、imately 40% of NOGE with 3 6 aromatic rings, but batch and supplier variations may occur. Average Mn approximately 345; Average epoxy groups per molecule, 2.2. 4.1.2 BFDGE.2H2O CAS no 72406-26-9 4.1.3 BFDGE CAS no 2095-03-6 NOTE 1 NOGE and its derivatives consist of a mixture of isomers (see Annexes
37、 A and D). The ratio of the various isomers may differ, depending on the supply source. Also the composition of the reference material may vary, depending on supply source and Lot number. NOTE 2 The substances of interest are those with more than two aromatic rings and at least one epoxy group as we
38、ll as their derivatives containing chlorohydrin functions and having a molecular mass less than 1000 Dalton. 4.2 Reagents NOTE During the analysis, unless otherwise stated, only reagents of recognized analytical grade and distilled water of equivalent purity should be used. 4.2.1 Acetonitrile, HPLC
39、grade 4.2.2 Boric acid 4.2.3 Methanol, HPLC grade 4.2.4 Sodium hydroxide 4.2.5 Water deionised, HPLC grade 4.3 Solutions 4.3.1 Borate buffer: 0,6 M Dissolve 9,28 g of boric acid in 220 ml of water. Add 4,5 M sodium hydroxide solution to a pH of 8,5. Fill the volume to 250 ml with water. EN 15137:200
40、6 (E) 7 4.3.2 Reference solutions of NOGE in acetonitrile (4 mg/ml) Weigh to the nearest 0,1 mg approximately 100 mg of NOGE (4.1) in a 25 ml volumetric flask. Fill the volumetric flask up to the mark with acetonitrile and mix carefully. Calculate the concentration of the substance in milligrams per
41、 millilitre solution. 4.3.3 Intermediate reference solution of NOGE in acetonitrile (160 g/ml) Pipette 1,0 ml of the stock solution (4.3.2) into a 25 ml volumetric flask and fill the flask up to the mark with acetonitrile to give a solution containing approximately 160 g/ml of NOGE. NOTE 1 The solut
42、ions prepared contain approximately 40 % of the components of interest (NOGE with 3 to 6 aromatic rings). NOTE 2 The solutions may be stored for up to 6 months in a refrigerator at a temperature between 4 C and 10 C. 4.3.4 Standard stock solutions of BFDGE in acetonitrile (500 g/ml) Weigh to the nea
43、rest 0,1 mg approximately 50 mg of BFGDE (4.1.3) in a 100 ml volumetric flask and add 80 ml acetonitrile (4.2.1), and mix thoroughly to dissolve the BFDGE. Fill the volumetric flask up to the mark with acetonitrile and mix carefully. Calculate the actual concentration of BFDGE in micrograms per mill
44、ilitre of solution. Repeat the procedure to obtain a second standard stock solution. Check the two primary standard solutions of analyte against one another. Check that the response factor, i.e. detector response divided by concentration of analyte solution, of the two primary standard solutions (or
45、 dilutions of that) does not differ by more than 5 %. If there is agreement within 5 %, make subsequent diluted standard solutions from only one of the primary standard solutions. If the levels of the two independently prepared stock solutions do not correspond to within 5 %, discard both stock solu
46、tions and prepare new solutions. 4.3.5 Intermediate standard solution of BFDGE in acetonitrile (10 g/ml) Into a 50 ml volumetric flask pipette 1,0 ml of the BFDGE stock solution (4.3.4) and fill the volumetric flask up to the mark with acetonitrile and mix carefully. Calculate the actual concentrati
47、on of BFDGE in g/ml solution. NOTE The solutions may be stored for up to 6 months in a refrigerator at a temperature between 4 C and 10 C. 4.3.6 Sodium hydroxide solution in water; 4,5 M Dissolve 18 g of NaOH in 100 ml of water. EN 15137:2006 (E) 8 5 Apparatus 5.1 Analytical balance, capable of weig
48、hing accurately to 0,1 mg. 5.2 HPLC vials. 5.3 Headspace vials of suitable volume, with inert gas-tight closure capable of sustaining the build-up of pressure during the heating period. 5.4 Micro pipette. 5.5 Oven, capable of being maintained at 100 C 5 C. 5.6 pH meter, accurate to within pH 0,1. 5.
49、7 Mixer of vortex type. 5.8 Reaction-therm heating module with nitrogen gas flow supply and the temperature set to between 40 C to 50 C. 5.9 HPLC apparatus 5.9.1 High performance liquid chromatograph provided with an injector, 20 l to 50 l, a UV detector at 225 nm, and a variable fluorescence detector, set to ex=275 nm and em=305 nm, detectors should be connected to an integrator. NOTE For the determination of NOGE the use of the prescribed fluorescence wavelengths is essential. Alternative wavelengths may provide
