EN ISO 12193:1999

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Tierische und pflanzliche Fette und Öle - Bestimmung des Bleigehaltes - Graphitofen - Atomabsorptionsverfahren (ISO 12193:1994)Corps gras d'origines animale et végétale - Détermination de la teneur en plomb - Méthode par spectrométrie d'absorption atomique avec four en graphite (ISO 12193:1994)Animal and vegetable fats and oils - Determination of lead content - Graphite furnace atomic absorption method (ISO 12193:1994)67.200.10Animal and vegetable fats and oilsICS:Ta slovenski standard je istoveten z:EN ISO 12193:1999SIST EN ISO 12193:2000en01-julij-2000SIST EN ISO 12193:2000SLOVENSKI
STANDARD
INTERNATIONAL STANDARD ISO 12193 First edition 1994-11-01 Animal and vegetable fats and oils - Determination of lead content - Graphite furnace atomic absorption method Corps gras d’origines animale et v6g&ale - Determination de Ia teneur en plomb - Methode par spectromktrie d’absorption atomique avec four en graphite. Reference number ISO 12193:1994(E) SIST EN ISO 12193:2000

ISO 12193:1994(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national Standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Esch member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. International Standard ISO 12193 was prepared by Technical Committee ISOfTC 34, Agricultural food products, Subcommittee SC 11, Animal and vegetable fats and oils. Annex A of this International Standard is for information only. 0 ISO 1994 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronie or mechanical, including photocopying and microfilm, without Permission in writing from the publisher. International Organization for Standardization Case Postale 56 l CH-l 211 Geneve 20 l Switzerland Printed in Switzerland ii SIST EN ISO 12193:2000

INTERNATIONAL STANDARD 0 ISO ISO 12193:1994(E) Animal and vegetable fats and oils - Determination of lead content - Graphite furnace atomic absorption method 1 Scope This International Standard specifies a method for the determination of trace amounts (< 0,l mg/kg) of lead in animal and vegetable fats and oils, referred to hereinafter as fats. 2 Normative references The following Standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publi- cation, the editions indicated were valid. All Standards are subject to revision, and Parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most re- cent editions of the Standards indicated below. Members of IEC and ISO maintain registers of cur- rently valid International Standards. ISO 661:1989, Animal and vegetable fats and oils - Prepara tion of test Sample. ISO 3696: 1987, Wa ter for analytical laboratory use - Specification and test methods. 3 Principle Vaporization of a test Portion of the fat in a graphite furnace connected to an atomic absorption spectrometer, previously calibrated using Standard solutions of an organo compound of lead. Calculation of the lead content from the absorbance at a selected wavelength of 283,3 nm. 4 Reagents Use only reagents of recognized analytical grade and water in accordance with grade 2 of ISO 3696. 4.1 Cyclohexane 4.2 Dilution Oil, for example a refined edible Oil, liquid at ambient temperature. Store the oil in a metal-free poylethylene or polypropylene bottle (5.1). The lead content of the oil shall be not greater than 1 pg/kg. NOTE 1 Refined edible oils have a lead content below 1 wlkg. 4.3 Standard stock Solution By appropriate dilution of an organo-lead Standard with the dilution oil (4.21, prepare a stock Solution with a lead content of 10 mg/kg. NOTE 2 A suitable Standard is available from Continental Oil Company, Ponca City, Oklahoma, USA (Conostan, 5 000 mg/kg), or Merck, D-l 600 Darmstadt, Germany (1 000 mg/kg).l) 4.4 Standard working solutions Prepare working solutions as required on the day of use with lead contents of 0,020 mg/kg, 0,050 mg/kg and 0,100 mg/kg, by diluting the stock Solution (4.3) with the dilution oil (4.2). 4.5 n-Heptane 1) This information is given for the convenience of users of this international Standard and does not constitute an endorsement by ISO of this product. 1 SIST EN ISO 12193:2000

ISO 12193:1994(E) 0 ISO 4.6 Matrix modifier Dissolve 2 g of soya lecithin with a phosphorus con- tent of approximately 2 % (m/m) in 100 ml of cyclo- hexane. NOTE 3 A suitable lecithin is available from Unimills Zwijndrecht, Netherlands, or Verein Deutscher Oelfabriken, D-6800 Mannheim, Germany (Bolec M), or Lucas Meyer GmbH & Co., D-2000 Hamburg, Germany.1) 4.7 Argon, minimum purity 99,99 %. 5.8 Pyrolytic platform (optional). 6 Sampling lt is important that the laborator-y receive a Sample which is truly representative and has not been dam- aged or changed during transport and storage. Sampling is not part of the method specified in this International Standard. A recommended sampling method is given in ISO 5555. NOTE 4 If argon is not available, nitrogen may be used as the purge gas. At temperatures above 2 300 “C, nitrogen forms the toxic gas hydrogen cyanide, therefore continuous Ventilation of the furnace area is necessary. 7 Preparation of test Sample Prepare the test Sample in accordance with ISO 661. 5 Apparatus Usual laboratoty equipment and, in particular, the fol- lowing. DO not filter the test Sample. 8 Procedure NOTE 8 If it is required to check whether the repeat- 5.1 Bottles and taps, made of polyethylene or polypropylene, metal-free, of 20 ml capacity. ability requirement is met, carry out two Single determi- nations under repeatability conditions. NOTE 5 If necessary, the polyethylene or polypropylene bottles and taps may be rendered metal-free by cleaning thoroughly with warm nitric acid soluton [c(HNO~) = 1 mol/l], rins
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