4876 (ISo International Standard INTERNATIONALORGANIZATION FOR STANDARDIZATION MEXKAYHAPOAHAROPTAHM3ALMR NO CTAHAAPTW3AUWWORGANISATION INTERNATIONALEDE NORMALISATION ANsI Internat Doc Sect Tobacco and tobacco products -- Determination of maleic hydrazide residues Tabac et produits du tabac --- Détermination des residus d'hydrazide maléique First edition - 1980-04-01 "APR 1 8 1980 UDC 663.97 : 543.8 Ref. No. ISO 4876-1980(E) ISO 4876-1980 (E) Descriptors : tobacco, chemical analysis, determination of content, residues, spectrophotometric analysis, test equipment. Price based on 6 pages Not for Resale Foreword ISo (the International Organization for Standardization) is a worldwide federation of national standards institutes (IsO member bodies). The work of developing Inter- national Standards is carried out through IsO technical committees. Every member body interested in a subject for which a technical committee has been set up 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. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the ISo Council. International Standard ISO 4876 was developed by Technical Committee ISO/TC 126, Tobacco and tobacco products, and was circulated to the member bodies in November 1978. It has been approved by the member bodies of the following countries : Australia Ireland Sweden Belgium Italy Switzerland Brazil Korea, Rep. of Thailand Bulgaria Turkey Mexico Czechoslovakia Netherlands United Kingdom Egypt, Arab Rep. of Romania USSR Greece South Africa, Rep. of Yugoslavia India Spain The member body of the following country expressed disapproval of the document on technical grounds : Germany, F. R. @ International Organization for Standardization, 1980 Printed in Switzerland Copyright International Organization for Standardization ISO 4876-1980 (E) INTERNATIONAL STANDARD Tobacco and tobacco products - Determination of maleic hydrazide residues Scope and field of application Purification of reagent 4.1.1 This International Standard specifies a method for the deter- Dissolve 20 g of 4-dimethylaminobenzaldehyde in 150 ml of ab- mination of maleic hydrazide residues in tobacco and tobacco solute ethanol. Add 5 g of powdered activated charcoal and stir products. mechanically for 5 min. Filter through a Buchner funnel and add, slowly and with constant stirring, 200 ml of water at 0 oC The method is applicable to tobacco and tobacco products and to the filtrate. Filter the white or pate yellow crystals on a to the residues from maleic hydrazide sucker control agents Buchner funnel and wash the crystals with 50 ml of cold water used on tobacco crops. Dry in a vacuum desiccator over phosphorus(V) oxide and store in a dark bottle. 2 References 4.1.2 Preparation of reagent solution iso 1042, Laboratory glassware -- One-mark volumetric Dissolve 2 g of the purified crystals in 100 ml of the 0,5 M flasks. sulphuric acid solution (4.6); filter through a sintered glass filter Iso 1770, Solid-stem general purpose thermometers. 1) funnel, if necessary. ISo 4793, Laboratory sintered (fritted) filters - Porosity The reagent is stable for up to 1 month if stored in the dark in a grading, classification and designation2). refrigerator; otherwise fresh reagent should be prepared daily. ISso 4874, Tobacco and tobacco products - ( General condi- tions of sampling.2) 4.2 Maleic hydrazide, standard solution corresponding to 10 μg /ml. 3 Principle Weigh, to the nearest 0,1 mg, 10 mg of pure maleic hydrazide, dissolve it in 100 ml of 0,1 M sodium hydroxide solution (4.5) Boiling of the test portion with sodium hydroxide solution to and dilute to 1 000 ml with water. remove volatile basic compounds. Addition of granulated zinc and reduction by the nascent hydrogen of the maleic hydrazide 4.3 Granulated