SIST EN 71-12:2013

Safety of toys - Part 12: N-nitrosamines and N-nitrosatable substances

This European Standard specifies the requirements and test methods for N-nitrosamines and N-nitrosatable substances for: - toys and parts of toys made from elastomers and intended for use by children under 36 months; - toys and parts of toys made from elastomers and intended to be placed in the mouth; - finger paints for children under 36 months.

Sicherheit von Spielzeug - Teil 12: N-Nitrosamine und N-nitrosierbare Stoffe

Diese Europäische Norm legt Anforderungen und Prüfverfahren zu N-Nitrosaminen und N-nitrosierbaren Stoffen für folgendes Spielzeug fest:
-   Spielzeug und Spielzeugteile aus Elastomeren, die für die Verwendung durch Kinder unter 36 Monaten vorgesehen sind;
-   Spielzeug und Spielzeugteile aus Elastomeren, die in den Mund genommen werden sollen;
-   Fingermalfarben für Kinder unter 36 Monaten.
BEISPIEL   Luftballons und Beißringe sind Beispiele für Spielzeug aus Elastomeren.

Sécurité des jouets - Partie 12: N-nitrosamines et substances N-nitrosables

La présente Norme européenne spécifie les exigences et les méthodes d’essai relatives aux N-nitrosamines et aux substances N-nitrosables pour :
   les jouets et parties de jouets en élastomères et destinés à l’usage d’enfants de moins de 36 mois ;
   les jouets et parties de jouets en élastomères et destinés à être mis en bouche ;
   les peintures au doigt destinées aux enfants de moins de 36 mois.
EXEMPLES   Les ballons de baudruche et les anneaux de dentition sont des exemples de jouets en matériaux élastomères.

Varnost igrač - 12. del: N-nitrozamini in N-nitrozabilne snovi

Ta evropski standard določa zahteve in preskusne metode za N-nitrozamine in N-nitrozabilne snovi za: – igrače in dele igrač, izdelane iz elastomera in namenjene uporabi otrok, mlajših od 36 mesecev; – igrače in dele igrač, izdelane iz elastomera in namenjene dajanju v usta; – prstne barve za otroke, mlajše od 36 mesecev.

General Information

• Status: Withdrawn
• Public Enquiry End Date: 19-Jun-2012
• Publication Date: 10-Jul-2013
• Withdrawal Date: 06-Feb-2017
• ICS: 97.200.50 - Toys
• Technical Committee: OTR - Child use and care article
• Current Stage: 9900 - Withdrawal (Adopted Project)
• Start Date: 07-Feb-2017
• Due Date: 02-Mar-2017
• Completion Date: 07-Feb-2017
• Directive: 2009/48/EC - DIRECTIVE 2009/48/EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 18 June 2009 on the safety of toys
• Mandate: M/445 - Standardisation mandate addressed to CEN and CENELEC within the framework of Directive 2009/48/EC revising Directive 88/378/EEC concerning the safety of Toys
• Ref Project: EN 71-12:2013 - Safety of toys - Part 12: N-Nitrosamines and N-nitrosatable substances

Relations

• Replaced By: SIST EN 71-12:2017 - Safety of toys - Part 12: N-Nitrosamines and N-nitrosatable substances
• Effective Date: 01-Apr-2017

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 71-12:2013
01-september-2013
9DUQRVWLJUDþGHO1QLWUR]DPLQLLQ1QLWUR]DELOQHVQRYL
Safety of toys - Part 12: N-nitrosamines and N-nitrosatable substances
Sicherheit von Spielzeug - Teil 12: N-Nitrosamine und N-nitrosierbare Stoffe
Sécurité des jouets - Partie 12: N-nitrosamines et substances N-nitrosables
Ta slovenski standard je istoveten z: EN 71-12:2013
ICS:
97.200.50 ,JUDþH Toys
SIST EN 71-12:2013 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 71-12:2013

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SIST EN 71-12:2013


EUROPEAN STANDARD
EN 71-12

NORME EUROPÉENNE

EUROPÄISCHE NORM
June 2013
ICS 97.200.50
English Version
Safety of toys - Part 12: N-Nitrosamines and N-nitrosatable
substances
Sécurité des jouets - Partie 12: N-Nitrosamines et Sicherheit von Spielzeug - Teil 12: N-Nitrosamine und N-
substances N-nitrosables nitrosierbare Stoffe
This European Standard was approved by CEN on 29 May 2013.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving 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 official 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 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, Sweden, Switzerland, Turkey and United
Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2013 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 71-12:2013: E
worldwide for CEN national Members.

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SIST EN 71-12:2013
EN 71-12:2013 (E)
Contents Page
Foreword . 4
Introduction . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Requirements . 8
4.1 Requirements for finger paints . 8
4.2 Requirements for elastomers . 8
5 Principle. 9
6 Reagents and apparatus . 9
6.1 Reagents . 9
6.2 Standards . 10
6.3 Apparatus . 10
7 Sample preparation . 11
7.1 General . 11
7.2 Finger paints . 11
7.2.1 N-nitrosamines . 11
7.2.2 N-nitrosatable substances . 11
7.3 Elastomers. 12
7.3.1 Sample preparation for balloons . 12
7.3.2 Sample preparation for other toys or parts of toys than balloons . 12
7.3.3 Nitrosation . 13
7.3.4 Preparation of solution for determination of N-nitrosamines by HPLC-MS/MS . 13
8 Methods of analysis . 13
8.1 General . 13
8.2 HPLC chromatographic conditions . 13
8.3 MS/MS conditions . 14
8.4 Confirmation of detected N-nitrosamines . 15
9 Calculation of results for N-nitrosamines and N-nitrosatable substances . 16
9.1 Finger paint . 16
9.1.1 General . 16
9.1.2 N-nitrosamines . 16
9.1.3 N-nitrosatable substances . 17
9.2 Elastomers. 17
9.2.1 General . 17
9.2.2 N-nitrosamines . 18
9.2.3 N-nitrosatable substances . 18
10 Quality . 19
10.1 Finger paints . 19
10.1.1 Repeatability, reproducibility and measurement uncertainty . 19
10.1.2 Limits of detection (LOD) and quantification (LOQ) . 19
10.2 Elastomers. 19
10.2.1 Repeatability, reproducibility and measurement uncertainty . 19
10.2.2 Limits of detection and quantification . 20
11 Test report . 20
Annex A (informative) Background and rationale for this European Standard . 22
A.1 Requirements for finger paints (see 4.1) . 22
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SIST EN 71-12:2013
EN 71-12:2013 (E)
A.2 Requirements for elastomers (see 4.2).2 2
A.3 Avoidance N-nitrosamines in finger paints .2 2
A.4 Explanation for decision to do static migration for elastomers . 22
A.5 Reference to other standards and relevant deviations . 23
A.6 Conditions for nitrosation .2 3
A.7 NDELA in balloons .2 3
A.8 Selection of N-nitrosamines specified in this standard . 23
Annex B (informative) Sample storage conditions .2 4
Annex C (informative) A-deviations .2 5
Annex ZA (informative) Relationship between this European Standard and the Essential
Requirements of EU Directive 2009/48/EC .2 6
Bibliography .2 7

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SIST EN 71-12:2013
EN 71-12:2013 (E)
Foreword
This document (EN 71-12:2013) has been prepared by Technical Committee CEN/TC 52 “Safety of toys”, the
secretariat of which is held by DS.
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 December 2013, and conflicting national standards shall be withdrawn
at the latest by December 2013.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
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), see informative Annex ZA, which is an integral part of this document.
th
This European Standard constitutes the 12 part of the European Standard on safety of toys.
This European Standard for safety of toys consists of the following parts:
 Part 1: Mechanical and physical properties;
 Part 2: Flammability;
 Part 3: Migration of certain elements;
 Part 4: Experimental sets for chemistry and related activities;
 Part 5: Chemical toys (sets) other than experimental sets;
 Part 7: Finger paints — Requirements and test methods;
 Part 8: Activity toys for domestic use;
 Part 9: Organic chemical compounds — Requirements;
 Part 10: Organic chemical compounds — Sample preparation and extraction;
 Part 11: Organic chemical compounds — Methods of analysis;
 Part 12: N-nitrosamines and N-nitrosatable substances;
 Part 13: Olfactory board games, gustative board games, cosmetic kits and gustative kits;
 Part 14: Trampolines for domestic use.
NOTE 1 In addition to the above parts of EN 71, the following guidance documents have been published: CEN Report,
CR 14379, Classification of toys — Guidelines, CEN Technical Report CEN/TR 15071, Safety of toys — National
translations of warnings and instructions for use in EN 71, and CEN Technical Report CEN/TR 15371, Safety of toys —
Replies to requests for interpretation of EN 71-1, EN 71-2, and EN 71-8.
NOTE 2 Words in italics are defined in Clause 3 (Terms and definitions).
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SIST EN 71-12:2013
EN 71-12:2013 (E)
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
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.
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SIST EN 71-12:2013
EN 71-12:2013 (E)
Introduction
There are ongoing developments in the following area:
 the influence of the mouthing behaviour (mouthing time and sucking/chewing) on the migration out of
teethers and other elastomers than balloons.
WARNING — N-nitrosamines can endanger human health owing to their toxicity. Persons using this
European Standard should be familiar with normal laboratory practice. This European Standard does
not purport to address all of the safety problems, if any, associated with its use. It is the responsibility
of the user to establish appropriate safety and health practices and to ensure compliance with any
national regulatory conditions.
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SIST EN 71-12:2013
EN 71-12:2013 (E)
1 Scope
This European Standard specifies the requirements and test methods for N-nitrosamines and N-nitrosatable
substances for:
 toys and parts of toys made from elastomers and intended for use by children under 36 months;
 toys and parts of toys made from elastomers and intended to be placed in the mouth;
 finger paints for children under 36 months.
EXAMPLES Examples of toys made from elastomers are balloons and teethers.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
EN ISO 3696, Water for analytical laboratory use — Specification and test methods (ISO 3696)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
finger paint
paste and/or jelly like, coloured mixture specially designed for children to apply directly to suitable surfaces
with the fingers and hands
Note 1 to entry: In addition to water, finger paints essentially consist of colorants, binders, preservatives and
embittering agent and may additionally contain extenders, humectants and surfactants.
[SOURCE: prEN 71-7:2012, 3.1]
3.2
elastomer
material which undergoes substantial, elastic ((fully) reversible) deformation when put under stress and
consisting of three-dimensional networks of cross-linked flexible polymers
Note 1 to entry: The cross-links can be chemical bonds in rubbers (like natural rubber, synthetic rubber and silicones)
or physical, thermo-reversible fixation points in thermoplastic elastomers (TPE) or the combination of both (TPE-V).
3.3
N-nitrosamine
substance characterised by the -N-N=O functional group, usually formed by the reaction of an amine with a
nitrosating agent at acidic pH
Note 1 to entry: The reacting amines primarily are secondary amines.
Note 2 to entry: An example for a nitrosating agent is nitrite.
3.4
N-nitrosatable substance
substance which when released into the test solution undergoes nitrosation to form a N-nitrosamine under
specified conditions
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EN 71-12:2013 (E)
4 Requirements
4.1 Requirements for finger paints
The concentration of N-nitrosamines in finger paints shall not exceed 0,02 mg/kg when tested in accordance
with 7.2 and Clause 8, calculated as sum of all detected N-nitrosamines according to 9.1.
The migration of N-nitrosatable substances from finger paints shall not exceed 1 mg/kg of toy material,
calculated as sum of all detected N-nitrosamines after nitrosation.
At least the substance in Table 1 shall be tested in finger paint. If there are indications of the presence of other
N-nitrosamines, they should also be tested.
Table 1 — List of N-nitrosamines in finger paints
Name of the substance CAS number Abbreviation
N-nitrosodiethanolamine 1116-54-7 NDELA

4.2 Requirements for elastomers
The migration of N-nitrosamines from toys intended for use by children under 36 months or in other toys or
parts of toys intended to be placed into the mouth shall not exceed 0,05 mg/kg of toy material when tested in
accordance with 7.3 and Clause 8, calculated as sum of all detected N-nitrosamines according to 9.2.
The migration of N-nitrosatable substances from toys intended for use by children under 36 months or in other
toys or parts of toys intended to be placed into the mouth shall not exceed 1 mg/kg of toy material, calculated
as sum of all detected N-nitrosamines after nitrosation.
At least the substances in Table 2 shall be tested in elastomers. If there are indications of the presence of
other N-nitrosamines they should also be tested.
Table 2 — List of N-nitrosamines in elastomers
Name of the substance CAS number Abbreviation
N-nitrosodiethanolamine 1116-54-7 NDELA
N-nitrosodimethylamine 62-75-9 NDMA
N-nitrosodiethylamie 55-18-5 NDEA
N-nitrosodipropylamine 621-64-7 NDPA
N-nitrosodiisopropylamine 601-77-4 NDiPA
N-nitrosodibutylamine 924-16-3 NDBA
N-nitrosodiisobutylamine 997-95-5 NDiBA
N-nitrosodiisononylamine 1207995-62-7 NDiNA
N-nitrosomorpholine 59-89-2 NMOR
N-nitrosopiperidine 100-75-4 NPIP
N-nitrosodibenzylamine 5336-53-8 NDBzA
N-nitroso-N-methyl-N-phenylamine 614-00-6 NMPhA
N-nitroso-N-ethyl-N-phenylamine 612-64-6 NEPhA

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5 Principle
N-nitrosamines and N-nitrosatable substances migrate into a test solution. N-nitrosatable substances are
converted to N-nitrosamines by acidification. The final test solutions are analysed for N-nitrosamines by a
suitable validated analytical technique. The N-nitrosamines and N-nitrosatable substances are expressed in
mg/kg of sample.
The test solution for N-nitrosamines in finger paints is water. The test solution for N-nitrosatable substances in
finger paints and for N-nitrosamines and N-nitrosatable substances in elastomers is saliva test solution.
6 Reagents and apparatus
6.1 Reagents
Unless otherwise specified, all reagents shall be of analytical grade and distilled water, or water of equivalent
purity conforming to at least grade 3 of EN ISO 3696.
N-nitrosamines are degraded by ultra-violet light. Exposure of extracts or standards to sources such as
sunlight or fluorescent tube light should be avoided. The samples and standards shall be protected by
wrapping in aluminium foil or using amber glassware and stored in the dark at a temperature of (5 ± 3) °C.
6.1.1 Sodium hydrogen carbonate.
6.1.2 Sodium chloride.
6.1.3 Potassium carbonate.
6.1.4 Sodium nitrite.
6.1.5 Hydrochloric acid solution, c(HCL) = 0,1 mol/l.
6.1.6 Sodium hydroxide solution, c(NaOH) = 0,1 mol/l.
6.1.7 Saliva test solution.
Dissolve 4,2 g of the sodium hydrogen carbonate (6.1.1), 0,5 g of the sodium chloride (6.1.2), 0,2 g of the
potassium carbonate (6.1.3) and 30 mg of the sodium nitrite (6.1.4) in water and dilute to 900 ml with water.
Adjust to pH 9,0 if necessary by adding the hydrochloric acid solution (6.1.5) or sodium hydroxide solution
(6.1.6) drop by drop. Transfer into a 1 l volumetric flask and dilute to the mark with water.
The saliva test solution shall be prepared freshly every day to ensure an accurate nitrite concentration. If the
solution is stored and not prepared freshly the laboratory shall prove that the nitrite concentration has not
decreased during storage.
6.1.8 Hydrochloric acid solution, c(HCL) = 1 mol/l.
6.1.9 Sodium hydroxide solution, c(NaOH) = 1 mol/l.
6.1.10 Methanol, ≥ 99,9 %, HPLC-grade.
6.1.11 Formic acid, ≥ 99,5 %, LC-MS grade.
6.1.12 Eluent A: 0,1 % (volume fraction) formic acid in water.
6.1.13 Eluent B: 0,1 % (volume fraction) formic acid in methanol.
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6.2 Standards
6.2.1 N-nitrosamines or their solutions, with known purities.
6.2.2 Internal standard, d8-N-nitrosodiethanolamine (d8-NDELA), with known purity.
6.2.3 Internal standard, d6-N-nitrosodimethylamine (d6-NDMA), with known purity.
6.2.4 Stock solution of N-nitrosamines.
Prepare a stock solution containing 10 mg/l of each N-nitrosamine (6.2.1) in methanol (6.1.10). This solution
shall be stored in the absence of light at (-18 ± 3) °C.
NOTE Certified N-nitrosamines standards can be purchased from several suppliers including storage and stability
information.
6.2.5 Solutions of internal standards.
6.2.5.1 Stock solution of internal standards for elastomers.
Prepare a stock solution containing 1 mg/l d8-NDELA (6.2.2) and d6-NDMA (6.2.3) in methanol (6.1.10). This
solution shall be stored in the absence of light at (-18 ± 3) °C.
6.2.5.2 Working solution of internal standards for finger paints.
Prepare an internal standard working solution containing 1 mg/l d8-NDELA (6.2.2) in water. This solution has
a stability of one day.
6.2.6 Calibration solutions.
6.2.6.1 Calibration solutions for N-nitrosamines in finger paints.
Prepare five calibration solutions by diluting the stock solution of the N-nitrosamines (6.2.4) and the working
solution of d8-NDELA (6.2.5.2) with water. The concentrations of the calibration solutions shall be 0,001 mg/l,
0,002 mg/l, 0,005 mg/l, 0,010 mg/l and 0,020 mg/l. Each solution shall contain 0,010 mg/l of d8-NDELA.
These solutions have a stability of one day.
6.2.6.2 Calibration solutions for elastomers and nitrosatable substances in finger paints.
Prepare five calibration solutions by diluting the stock solutions of the N-nitrosamines (6.2.4) with saliva test
solution (6.1.7). The concentration range of the calibration solutions shall be 0,001 mg/l to 0,05 mg/l. To 1 ml
of each solution, add 0,020 ml of the internal standards stock solution containing d8-NDELA and d6-NDMA
(6.2.5.1). Shake to mix the solutions. These solutions have a stability of one day.
6.3 Apparatus
Laboratory equipment that can come into contact with the sample shall be free from N-nitrosamines.
Standard laboratory equipment and equipment appropriate for applying the test method shall be used. The
following equipment could be used when applying the test method specified in this standard.
6.3.1 Vortex mixer.
6.3.2 Shaking machine.
6.3.3 Centrifuge, capable of achieving not less than 20 000 g.
6.3.4 Oven, capable of maintaining a temperature of (40 ± 2) °C.
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EN 71-12:2013 (E)
6.3.5 High performance liquid chromatography apparatus coupled with tandem mass spectrometry
equipped with atmospheric pressure ionisation (APCI).
6.3.6 Analytical reversed phase HPLC column, C18, for example Macherey-Nagel, Nucleodur C18
1)
Sphinx®, column length 50 mm, internal diameter 3 mm, particle size 1,8 μm. .
NOTE Using this HPLC column and the conditions given in 8.2 NDELA was not eluted within the void volume. When
using another column it needs to be ensured that NDELA has sufficient retention and does not elute within the void
volume of the column used.
6.3.7 Membrane filter.
7 Sample preparation
NOTE Other determination methods than HPLC-MS/MS might require modifications of this procedure after the
migration. For nitrosation, it is mandatory to use the given volume ratios of sample solution, hydrochloric acid and sodium
hydroxide as well as the given time and temperature.
7.1 General
N-nitrosamines are degraded by ultra-violet light. Exposure of samples, extracts, migrates or standard
solutions to sources such as sunlight or fluorescent tube light shall be avoided. All extracts, migrates and
standard solutions shall be protected by wrapping in aluminium foil or using amber glassware. If not analysed
directly after preparing extracts, migrates and standard solutions shall be stored in the dark at a temperature
of (5 ± 3) °C.
For analysis of finger paints and elastomers a method blank should be prepared and analysed to check if
there are any blank values. For NDELA, blank values have been reported which originated from the HPLC-
vials used. This could be avoided by prewashing the HPLC-vials with ethanol. In the presence of N-
nitrosamines in the blank sample this shall be investigated and removed before analysing samples.
7.2 Finger paints
7.2.1 N-nitrosamines
Finger paints shall be homogenised by mixing (for example using a glass rod).
Weigh about 1,0 g of the sample (note the exact mass) into a sample tube, add 0,20 ml of d8-NDELA working
solution (6.2.5.2) and add 18,8 ml water. After vortexing for about 1 min, shake continuously for approximately
15 min on a shaking machine (6.3.2). Centrifuge the sample solution at approximately 4 000 g for about
15 min. Transfer a portion of the supernatant into a second sample tube and centrifuge at approximately
20 000 G for about 15 min. If necessary, filter the supernatant through a membrane filter which will not retain
analytes.
7.2.2 N-nitrosatable substances
Finger paints shall be homogenised by mixing (for example using a glass rod).
Weigh about 0,4 g of the sample (note the exact mass) into a sample tube and add saliva test solution until
the total weight is 20 g (note the exact mass). After vortexing for about 1 min, shake continuously for
approximately 15 min on a shaking machine (6.3.2) to homogenise the sample solution.

1) This information is given for the convenience of users of this European Standard and does not constitute an
endorsement by CEN of the product named. Equivalent products may be used if they can be shown to lead to the same
results.
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Transfer 5,0 ml of the test solution in an amber vial and add 0,5 ml of 1 mol/l hydrochloric acid solution (6.1.8).
Cap the vial, shake to mix and allow the solution to stand for (30 ± 1) min at (40 ± 2) °C. Add 1,0 ml of 1 mol/l
sodium hydroxide solution (6.1.9) and shake to mix. Transfer the solution in a centrifugation tube and
centrifuge the sample solution at 20 000 g for 15 min. If necessary, filter the supernatant through a membrane
filter.
This test solution should be stored in a refrigerator at (5 ± 3) °C and may be used to reanalyse for N-
nitrosamines.
Transfer immediately 1,0 ml of the test solution into an amber HPLC-Vial and add 0,020 ml of the internal
standards stock solution containing d8-NDELA and d6-NDMA (6.2.5.1). Shake to mix the solution. The
solution is now ready for measurement of N-nitrosamines after nitrosation.
In the event the measured N-nitrosamine concentrations are above the calibration range the test solutions
stored in the refrigerator may be diluted with saliva test solution for reanalysing.
7.3 Elastomers
7.3.1 Sample preparation for balloons
Cut the balloons longitudinal in two halves to obtain nearly symmetrical pieces. Depending on the weight of
the sample the halves shall be cut again longitudinal to get again two nearly symmetrical pieces. Weigh the
balloon halves and/or quarters in a 50 ml conical flask until the sample weight is between 3,5 g and 4,5 g. Add
a corresponding amount of saliva test solution ((6.1.7), preheated to (40 ± 2) °C) between 35,0 ml and 45,0 ml
to get a weight to volume ratio of 10. Ensure that the sample is totally immersed, e.g. by adding some glass
balls (preheated to (40 ± 2) °C). Close the flask with a ground stopper and allow the solution to stand at
(40 ± 2) °C for (60 ± 3) min.
Immediately decant the test solution into a suitable glass vessel to stop the migration process. The test
solution is used for both, the determination of N-nitrosamines ac
...