CEN/TS 13130-23:2005

Materials and articles in contact with foodstuffs - Plastics substances subject to limitation - Part 23: Determination of formaldehyde and hexamethylenetetramine in food simulants

This document, part of EN 13130, specifies an analytical procedure for the chemical conversion of HMTA to formaldehyde and the determination of formaldehyde in food simulants water, 3 % w/v aqueous acetic acid, 15 % v/v aqueous ethanol and rectified olive oil.
The method is appropriate for the quantitative determination of formaldehyde in approximate analyte concentration range of 3,0 mg to 30 mg formaldehyde per kilogram of food simulant, which corresponds to
2,3 mg to 23,3 mg hexamethylenetetramine per kilogram of food simulant.
NOTE   The method should also be applicable to other aqueous food simulants as well as to other fatty food simulants e.g. sunflower oil, corn oil or a mixture of synthetic triglycerides.

Werkstoffe und Gegenstände in Kontakt mit Lebensmitteln - Substanzen in Kunststoffen, die Beschränkungen unterliegen - Teil 23: Bestimmung von Formaldehyd und Hexamethylentetramin in Prüflebensmitteln

Diese Technische Spezifikation, Teil der EN 13130, legt ein Analyseverfahren für die chemische Umwandlung von HMTA in Formaldehyd und zur Bestimmung von Formaldehyd in den Prüflebensmitteln destilliertes Wasser, 3%ige Essigsäure (m/V) in wässriger Lösung, 15%iges Ethanol (Volumenanteil) in wässriger Lösung und rektifiziertes Olivenöl fest.
Das Verfahren eignet sich zur quantitativen Bestimmung von Formaldehyd im angenäherten Konzentrationsbereich des Analyten von 3,0 mg bis 30 mg Formaldehyd je Kilogramm Prüflebensmittel, das entspricht 2,3 mg bis 23,3 mg Hexamethylentetramin je Kilogramm Prüflebensmittel.
ANMERKUNG   Das Verfahren sollte auch auf andere wässrige Prüflebensmittel sowie weitere fettige Prüflebensmittel, z. B. Sonnenblumenöl, Maiskeimöl oder eine Mischung synthetischer Triglyceride, anwendbar sein.

Matériaux et objets en contact avec les denrées alimentaires - Substances dans les matières plastiques soumises à des limitations - Partie 23 : Détermination du formaldéhyde et de l'hexaméthylènetétramine dans les simulants d'aliments

Le présent document qui fait partie de l'EN 13130, spécifie un mode opératoire d'analyse pour la conversion chimique du HMTA en formaldéhyde et la détermination du formaldéhyde présent dans les quatre simulants d'aliments suivants : eau, solution aqueuse d'acide acétique à 3 % (m/v), solution aqueuse d'éthanol à 15 % (v/v) et huile d'olive rectifiée.
Cette méthode convient pour la détermination quantitative du formaldéhyde dans une gamme de concentrations d'analyte comprise approximativement entre 3,0 mg et 30 mg de formaldéhyde par kilogramme de simulant d'aliments, ce qui correspond à une concentration comprise entre 2,3 mg et 23,3 mg d'hexaméthylenètetramine par kilogramme de simulant d'aliments.
NOTE   ll convient que cette méthode puisse également être appliquée à d'autres simulants aqueux ainsi qu'à d'autres simulants gras tels que l'huile de tournesol, l'huile de maïs ou un mélange de triglycérides synthétiques.

Materiali in predmeti v stiku z živili - Snovi v polimernih materialih, katerih koncentracija je omejena - 23. del: Določevanje formaldehida in heksametilentetramina v modelnih raztopinah za živila

General Information

• Status: Published
• Publication Date: 22-Feb-2005
• ICS: 67.250 - Materials and articles in contact with foodstuffs
• Technical Committee: CEN/TC 194 - Utensils in contact with food
• Drafting Committee: CEN/TC 194/SC 1/WG 2 - Methods of test for monomers
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 23-Feb-2005
• Completion Date: 23-Feb-2005
• Ref Project: SIST-TS CEN/TS 13130-23:2005 - Materials and articles in contact with foodstuffs - Plastics substances subject to limitation - Part 23: Determination of formaldehyde and hexamethylenetetramine in food simulants

CEN/TS 13130-23:2005 - Overview

CEN/TS 13130-23:2005 is a CEN Technical Specification within the EN 13130 series for plastics materials and articles in contact with food. It specifies an analytical procedure for the chemical conversion of hexamethylenetetramine (HMTA) to formaldehyde and the quantitative determination of formaldehyde in food simulants. The method targets an approximate analyte range of 3.0–30 mg formaldehyde/kg food simulant (equivalent to 2.3–23.3 mg HMTA/kg). Food simulants covered include water, 3% w/v aqueous acetic acid, 15% v/v aqueous ethanol, and rectified olive oil, with applicability noted for other aqueous and fatty simulants (e.g., sunflower or corn oil).

Key topics and technical requirements

• Principle: Acid-catalysed conversion of HMTA to formaldehyde followed by spectrophotometric determination.
• Primary analytical reaction: Formaldehyde reacts with chromotropic acid in sulfuric acid to produce a measurable chromophore; measurement at 574 nm using a 10 mm cell.
• Confirmation method: Alternative quantitative method using acetylacetone (pentane-2,4-dione) with ammonium acetate forming 3,5-diacetyl-1,4-dihydrolutidine, measured at 410 nm. The two procedures were shown to be interchangeable in collaborative trials.
• Calibration and quantification: External standards prepared from known formaldehyde stock solutions; method precision and detection limits were pre-validated in inter-laboratory trials.
• Reagents & apparatus: Recommends analytical-grade reagents (chromotropic acid, sulfuric acid, acetone, etc.), spectrophotometer (preferably double-beam), water bath and standard volumetric equipment.
• Scope limits: Designed for the stated concentration range; sample preparation and exposure conditions should follow EN 13130-1 guidance.

Practical applications

• Compliance testing of food-contact plastics for residual HMTA/formaldehyde migration.
• Quality control and routine lab analysis in contract testing laboratories and manufacturer QC labs.
• Regulatory support for demonstrating conformity with EU food contact legislation (as it stood at time of publication) and for risk assessment of migrating formaldehyde from plastic articles.
• Use in method development, validation, or as a reference procedure when assessing alternative food simulants.

Who should use this standard

• Analytical chemists and testing laboratories specializing in food contact materials.
• Plastic manufacturers, converters and packaging suppliers performing migration testing.
• Regulatory authorities and conformity assessors reviewing laboratory reports for food-contact compliance.

Related standards

• EN 13130-1 (Guide to test methods and selection of exposure conditions) - normative reference for sample preparation and migration conditions.
• Other EN 13130 parts covering specific monomers and migration test methods.

Keywords: formaldehyde in food simulants, hexamethylenetetramine (HMTA), plastics migration testing, CEN/TS 13130-23:2005, chromotropic acid spectrophotometry, food-contact materials.

Standards Content (Sample)

SLOVENSKI STANDARD
01-april-2005
0DWHULDOLLQSUHGPHWLYVWLNX]åLYLOL6QRYLYSROLPHUQLKPDWHULDOLKNDWHULK
NRQFHQWUDFLMDMHRPHMHQDGHO'RORþHYDQMHIRUPDOGHKLGDLQ
KHNVDPHWLOHQWHWUDPLQDYPRGHOQLKUD]WRSLQDK]DåLYLOD
Materials and articles in contact with foodstuffs - Plastics substances subject to limitation
- Part 23: Determination of formaldehyde and hexamethylenetetramine in food simulants
Werkstoffe und Gegenstände in Kontakt mit Lebensmitteln - Substanzen in Kunststoffen,
die Beschränkungen unterliegen - Teil 23: Bestimmung von Formaldehyd und
Hexamethylentetramin in Prüflebensmitteln
Matériaux et objets en contact avec les denrées alimentaires - Substances dans les
matieres plastiques soumises a des limitations - Partie 23 : Détermination du
formaldéhyde et de l'hexaméthylenetétramine dans les simulants d'aliments
Ta slovenski standard je istoveten z: CEN/TS 13130-23:2005
ICS:
67.250 Materiali in predmeti v stiku z Materials and articles in
živili contact with foodstuffs
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

TECHNICAL SPECIFICATION
CEN/TS 13130-23
SPÉCIFICATION TECHNIQUE
TECHNISCHE SPEZIFIKATION
February 2005
ICS 67.250
English version
Materials and articles in contact with foodstuffs - Plastics
substances subject to limitation - Part 23: Determination of
formaldehyde and hexamethylenetetramine in food simulants
Matériaux et objets en contact avec les denrées Werkstoffe und Gegenstände in Kontakt mit Lebensmitteln
alimentaires - Substances dans les matières plastiques - Substanzen in Kunststoffen, die Beschränkungen
soumises à des limitations - Partie 23 : Détermination du unterliegen - Teil 23: Bestimmung von Formaldehyd und
formaldéhyde et de l'hexaméthylènetétramine dans les Hexamethylentetramin in Prüflebensmitteln
simulants d'aliments
This Technical Specification (CEN/TS) was approved by CEN on 16 December 2004 for provisional application.
The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit their
comments, particularly on the question whether the CEN/TS can be converted into a European Standard.
CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS available
promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the CEN/TS)
until the final decision about the possible conversion of the CEN/TS into an EN is reached.
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, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,
Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2005 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 13130-23:2005: E
worldwide for CEN national Members.

Contents
page
Foreword .3
Introduction.5
1 Scope.6
2 Normative references.6
3 Principle .6
4 Reagents .6
5 Apparatus.8
6 Samples.9
7 Procedure.10
8 Precision .12
9 Confirmation .13
10 Test report.15
Bibliography.16

Foreword
This document (CEN/TS 13130-23:2005) has been prepared by Technical Committee CEN/TC 194 “Utensils
in contact with food”, the secretariat of which is held by BSI.
This part of EN 13130 has been prepared within the Standards, Measurement and Testing project,
MAT1-CT92-0006, “Development of Methods of Analysis for Monomers” and has been prepared by
Subcommittee (SC 1) of TC 194 "Utensils in contact with food" as one of a series of test methods for plastics
materials and articles in contact with foodstuffs.
This standard is intended to support Directives 2002/72/EC [1], 89/109/EEC [2], 82/711/EEC [3] and its
amendments 93/8/EEC [4] and 97/48/EC [5], and 85/572/EEC [6].
At the time of preparation and publication of this part of EN 13130 the European Union legislation relating to
plastics materials and articles intended to come into contact with foodstuffs is incomplete. Further Directives
and amendments to existing Directives are expected which could change the legislative requirements which
this standard supports. It is therefore strongly recommended that users of this standard refer to the latest
relevant published Directive(s) before commencement of a test or tests described in this standard.
This part of EN 13130 should be read in conjunction with EN 13130-1.
Further parts of EN 13130, under the general title Materials and articles in contact with foodstuffs - Plastics
substances subject to limitation, have been prepared, and others are in preparation, concerned with the
determination of specific migration from plastics materials into foodstuffs and food simulants and the
determination of specific monomers and additives in plastics. The parts of EN 13130 are as follows.
Part 1: Guide to 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 conditions of exposure to food
simulants
Part 2: Determination of terephthalic acid in food simulants
Part 3: Determination of acrylonitrile in food and food simulants
Part 4: Determination of 1,3-butadiene in plastics
Part 5: Determination of vinylidene chloride in food simulants
Part 6: Determination of vinylidene chloride in plastics
Part 7: Determination of monoethylene glycol and diethylene glycol in food simulants
Part 8: Determination of isocyanates in plastics
Part 9: Determination of acetic acid, vinyl ester in food simulants
Part 10: Determination of acrylamide in food simulants
Part 11: Determination of 11-aminoundecanoic acid in food simulants
Part 12: Determination of 1,3-benzenedimethanamine in food simulants
Part 13: Determination of 2,2-bis(4-hydroxyphenyl)propane (Bisphenol A) in food simulants
Part 14: Determination of 3,3-bis(3-methyl-4-hydroxyphenyl)-2-indoline in food simulants
Part 15: Determination of 1,3-butadiene in food simulants
Part 16: Determination of caprolactam and caprolactam salt in food simulants
Part 17: Determination of carbonyl chloride in plastics
Part 18: Determination of 1,2-dihydroxybenzene, 1,3-dihydroxybenzene,
1,4-dihydroxybenzene, 4,4’-dihydroxybenzophenone and 4,4’dihydroxybiphenyl in food simulants
Part 19: Determination of dimethylaminoethanol in food simulants
Part 20: Determination of epichlorohydrin in plastics
Part 21: Determination of ethylenediamine and hexamethylenediamine in food simulants
Part 22: Determination of ethylene oxide and propylene oxide in plastics
Part 23: Determination of formaldehyde and hexamethylenetetramine in food simulants
Part 24: Determination of maleic acid and maleic anhydride in food simulants
Part 25: Determination of 4-methyl-pentene in food simulants
Part 26: Determination of 1-octene and tetrahydrofuran in food simulants
Part 27: Determination of 2,4,6-triamino-1,3,5-triazine in food simulants
Part 28: Determination of 1,1,1-trimethylolpropane in food simulants
Parts 1 to 8 are European Standards. Parts 9 to 28 are Technical Specifications.
WARNING All chemicals are hazardous to health to a greater or lesser extent. It is beyond the
scope of this Technical Specification to give instructions for the safe handling of all chemicals, that
meet, in full, the legal obligations in all countries in which this Technical Specification may be
followed. Therefore, specific warnings are not given and users of this Technical Specification should
ensure that they meet all the necessary safety requirements in their own country.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to announce this CEN Technical Specification: Austria, Belgium, Cyprus, Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland
and United Kingdom.
Introduction
Formaldehyde, CH O, PM/Ref. No 17260, and hexamethylenetetramine, C H N , PM/Ref. No 18670, are
2 6 12 4
monomers used in the manufacture of certain plastics materials and articles intended to come into contact
with foodstuffs. After manufacture residual formaldehyde or residual hexamethylenetetramine (HMTA) can
remain in the finished product and may migrate into foodstuffs coming into contact with that product.
Since migration of HMTA is limited as formaldehyde, this method allows the determination of formaldehyde,
liberated from HMTA, in food simulants water, 3 % w/v aqueous acetic acid, 15 % v/v aqueous ethanol and
rectified olive oil.
The chemical conversion of HMTA to formaldehyde is as follows:
C H N + 6 H O → 6 CH O + 4 NH
6 12 4 2 2 3
The method allows the determination of HMTA and formaldehyde at the same time.
The method has been pre-validated by collaborative trial with two laboratories. The confirmation procedure
was found to be quantitative. In collaborative trials with three laboratories comparable results using the
chromotropic acid method and the acetyl acetone method were found for the detection limits, repeatability,
recovery and migration of formaldehyde. Therefore the method of determination and the confirmation
procedure are interchangeable.
1 Scope
This document, part of EN 13130, specifies an analytical procedure for the chemical conversion of HMTA to
formaldehyde and the determination of formaldehyde in food simulants water, 3 % w/v aqueous acetic acid,
15 % v/v aqueous ethanol and rectified olive oil.
The method is appropriate for the quantitative determination of formaldehyde in approximate analyte
concentration range of 3,0 mg to 30 mg formaldehyde per kilogram of food simulant, which corresponds to
2,3 mg to 23,3 mg hexamethylenetetramine per kilogram of food simulant.
NOTE The method should also be applicable to other aqueous food simulants as well as to other fatty food simulants
e.g. sunflower oil, corn oil or a mixture of synthetic triglycerides.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
EN 13130-1:2004, Materials and articles in contact with foodstuffs – Plastics substances subject to limitation –
Part 1: Guide to 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 conditions of exposure to food
simulants.
3 Principle
HMTA is treated with acid and heated to release formaldehyde.
Formaldehyde in food simulant is determined by spectrophotometry. Formaldehyde reacts with chromotropic
acid in the presence of sulfuric acid. This solution is measured in a spectrophotometer at the wavelength of
574 nm, with cells of an optical path length of 10 mm. Quantification is achieved using an external standard.
Confirmation of formaldehyde is carried out by spectrophotometer. Formaldehyde reacts with
pentane-2,4-dione in the presence of ammonium acetate to form 3,5-diacetyl-1,4-dihydrolutidine. The
absorption of this extract is measured at 410 nm, with a spectrophotometer with cells of an optical path length
of 10 mm.
NOTE The confirmation procedure is also a quantitative method and can therefore be used as the method of
determination. In that case the method with chromotropic acid should be used as the confirmation procedure.
4 Reagents
NOTE All reagents should be of recognized analytical quality unless otherwise stated.
4.1 Analyte
Formaldehyde solution, CH O, minimum 37 % (w/v), stabilized with approximately 10 % methanol.
4.2 Chemicals
4.2.1 Water, deionised.
4.2.2 Acetic acid, glacial 100 %.
4.2.3 Ethanol, absolute.
4.2.4 Olive oil, rectified (according to Directive 93/8/EEC)
4.2.5 Chromotropic acid disodium salt (dihydrate), 4,5-dihydroxy-2,7-naphthalene-disulfonic acid,
C H Na O S .2H O.
10 6 2 8 2 2
4.2.6 Sulfuric acid, density 1,84 g/cm .
4.2.7 Acetone
4.2.8 Starch, soluble
4.2.9 n-pentane
4.3 Solutions
4.3.1 90 % Acetone
Measure 900 ml of acetone (4.2.7) and make up with water (4.2.1) to 1 000 ml.
4.3.2 Stock solution of formaldehyde in water containing approximately 1,5 mg formaldehyde per
millilitre
Weigh to the nearest 1 mg approximately 0,8 g formaldehyde solution (4.1.1) into a 200 ml volumetric flask
and make up to the mark with water (4.2.1).
Determine the strength of this solution as follows.
Pipette 10,0 ml formaldehyde stock solution into a beaker, add 25,0 ml of a 0,05 mol standard iodine solution
(4.3.5) and 10,0 ml of 1 mol sodium hydroxide solution (4.3.6) to the beaker. Allow to stand for 5 min. Acidify
with 11,0 ml of 1 mol hydrochloric acid (4.3.7) and determine the excess iodine by titration with a 0,1 mol
standard sodium thiosulfate solution (4.3.8) using 0,1 ml of the starch solution (4.3.12) as indicator.
Make a blank test on the corresponding amount of standard iodine solution.
1 ml of 0,1 N iodine consumed is equivalent to 1,5 mg formaldehyde.
Calculate the concentration in mg formaldehyde per millilitre of solution.
Repeat the procedure to obtain a second stock solution.
Store the formaldehyde stock solution for up to 3 months in a refrigerator.
4.3.3 Stock solution of formaldehyde in 90 % acetone containing approximately 1 mg formaldehyde
per millilitre
Weigh to the nearest 1 mg approximately 0,3 g formaldehyde solution (4.1.1) into a 100 ml volumetric flask
and make up to the mark with 90 % acetone (4.3.1).
Calculate the concentration of formaldehyde in the 90 % acetone solution using the concentration of the 37 %
formaldehyde solution (4.1.1) derived from the result obtained in 4.3.2.
Repeat the procedure to obtain a second stock solution.
Store the solutions in well-closed containers in the dark for a maximum period of 3 months in a refrigerator.
4.3.4 Diluted standard solutions of formaldehyde in aqueous food simulants
Pipette into a series of five 100 ml volumetric flasks, 100 µl, 400 µl, 700 µl, 1 000 µl and 2 000 µl of the stock
solution (4.3.2). Make up to the mark with the appropriate food simulant. The standard solutions thus obtained
contain approximately 1,5 mg/l, 6,0 mg/l, 10,5 mg/l, 15 mg/l and 30 mg formaldehyde per litre.
Calculate the exact concentration in milligrams of formaldehyde per litre of solution corresponding to mg/kg
food simulant.
Repeat the procedure using the second standard stock solution to obtain a second set of diluted standard
solutions.
Store the solutions in well closed contained for a maximum period of 3 months in a refrigerator.
4.3.5 Iodine in aqueous solution, 0,05 M.
4.3.6 Sodium hydroxide in aqueous solution, NaOH, 1 M.
4.3.7 Hydrochloric acid in aqueous solution, HCl, 1 M.
4.3.8 Sodium thiosulfate in aqueous solution, Na S O .5H O, 0,1 M.
2 5 3 2
4.3.9 0,5 % chromotropic acid disodium salt (dihydrate)
Weigh 500 mg of chromotropic acid disodium salt (4.2.5) into a 100 ml volumetric flask and make to the mark
up with water (4.2.1). This solution shall be prepared freshly on the day of use.
4.3.10 Sulfuric acid solution
Measure 100 ml water (4.2.1) and make up with sulfuric acid (4.2.6) to 400 ml.
4.3.11 Sulfuric acid solution (4M)
Add carefully 222 ml sulfuric acid (4.2.6) to a flask containing approximately 700 ml of water. After cooling to
room temperature, make up to 1 000 ml with water (4.2.1).
4.3.12 Starch solution
Dissolve 1 g soluble starch (4.2.8) i
...