report of the interlaboratory comparison organised by the...
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Report EUR 25686 EN
2 0 1 2
Giorgia Beldì, Natalia Jakubowska, Oguzhan Yavuz and Catherine Simoneau
ILC01 2012- Formaldehyde and Melamine in 3% acetic acid migration solution
Report of the interlaboratory comparison organised by the European Reference Laboratory for Food Contact Materials
European Commission Joint Research Centre Institute for Health and Consumer Protection Contact information Catherine Simoneau Address: Joint Research Centre, Via Enrico Fermi 2749, TP 260, 21027 Ispra (VA), Italy E-mail: [email protected] Tel.: +39 0332 78 5889 Fax: +39 0332 78 5707 http://ihcp.jrc.ec.europa.eu/ http://www.jrc.ec.europa.eu/ This publication is a Reference Report by the Joint Research Centre of the European Commission. Legal Notice Neither the European Commission nor any person acting on behalf of the Commission is responsible for the use which might be made of this publication. Europe Direct is a service to help you find answers to your questions about the European Union Freephone number (*): 00 800 6 7 8 9 10 11 (*) Certain mobile telephone operators do not allow access to 00 800 numbers or these calls may be billed.
A great deal of additional information on the European Union is available on the Internet. It can be accessed through the Europa server http://europa.eu/. JRC77619 EUR 25686 EN ISBN 978-92-79-28085-6 ISSN 1831-9424 doi:10.2788/77358 Luxembourg: Publications Office of the European Union, 2012 © European Union, 2012 Reproduction is authorised provided the source is acknowledged. Printed in Italy
EURL – FCM ILC01 2012- Formaldehyde and melamine in food contact migration solution
Report of the interlaboratory comparison
ILC01 2012- Formaldehyde and Melamine in 3% acetic acid
migration solution
EC-JRC-IHCP, CAT Unit action 15014
2012
No SANCO/2011/FOOD SAFETY070-Food Contact Materials
Giorgia Beldì, Natalia Jakubowska, Oguzhan Yavuz and Catherine Simoneau
EURL – FCM ILC01 2012- Formaldehyde and melamine in food contact migration solution
4
Table of content 1. Summary...................................................................................................................... 5
2. Introduction ................................................................................................................. 6
3. Scope ........................................................................................................................... 6
4. Time frame................................................................................................................... 6
5. Test materials.............................................................................................................. 7
5.1 Preparation........................................................................................................... 7
5.2 Homogeneity assessment .................................................................................... 7
5.3 Stability test .......................................................................................................... 8
5.4 Distribution ........................................................................................................... 8
6. Instructions to participants........................................................................................ 8
7. Assigned values.......................................................................................................... 8
8. Target standard deviation .......................................................................................... 9
9. Evaluation of results................................................................................................... 9
9.1 General observations ........................................................................................... 9
9.2 Statistical evaluation of results ............................................................................. 9
9.2.1. Determination of the consensus value .......................................................... 9 9.2.2. Scores and evaluation criteria....................................................................... 9
9.3 Laboratory results and scores ............................................................................ 10
10. Migration exercise................................................................................................... 25
11. Conclusion .............................................................................................................. 31
12. Acknowledgements ................................................................................................ 33
12. References............................................................................................................... 35
13. Annexes ................................................................................................................... 35
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1. Summary
The Institute for Health and Consumer Protection (IHCP) of the European Commission’s Directorate-General Joint Research Centre hosts the EU Reference Laboratory for Food Contact Materials (EURL-FCM). One of its core tasks is to organise interlaboratory comparisons (ILCs) among appointed National Reference Laboratories (NRLs).
This report presents the results of the ILC of the EURL-FCM which focused on the quantification of formaldehyde and melamine in migration solutions of 3% acetic acid from food contact materials. The test material used for preparation of the migration solutions were melamine kitchenware (spoons). The migration was done in 3% acetic acid (w/v) which is the simulant for acidic foods and represents the worst case scenario for melamine plastics. The EURL prepared and distributed three concentration levels of migration solutions and three spoon samples (only for NRLs).
The general aim of the exercise was to assess the performance of the official control laboratories and consequently the participants were free to use any analytical method of their choice.
The homogeneity and stability studies were performed by the EURL-FCM laboratory. Participants were invited to report 4 results for each concentration level and 2 results for each spoon. Laboratory results were processed using several algorithms: ISO 13528 [1], Harmonized protocol [2], DIN 38402 A45 (Q-Hampel) [3] and ISO GUIDE 35:2006 [4]. The assigned values were obtained after applying the robust statistics to the results of the participants. Standard deviations for proficiency assessment (also called target standard deviations) were set based on Horwitz equation [5].
There were 70 participants to whom samples were dispatched (EURL, 27 NRLs + 42 Official Control Laboratories (OCLs) from Belgium, France, Germany, Italy, Poland, Slovenia, Spain and United Kingdom) and 66 of which submitted results, as follows: 4 for melamine only, 27 for formaldehyde only, and 35 for both formaldehyde and melamine. In the context of the physical check of formaldehyde the total results submitted were thus 62.
As a conclusion of the ILC exercise on the quantification of formaldehyde and melamine in the migration solutions of kitchenware in 3% acetic acid, this ILC showed that:
The level of participation was 94%, of which 88.5% for formaldehyde,56% for melamine and 50% for both substances under test. As this ILC targeted the correct implementation of Regulation 284/2011 on China and Hong Kong imports which requires the analysis of 10% of the consignments, all reporting laboratories were expected to report at least results for formaldehyde.
The level of success in the exercise was of 80% of correctly estimated results for formaldehyde and 89% for melamine (for all three concentration levels) when considering all 66 laboratories comprising of NRLs and OCLs. With regards to the performance of NRLs only, 79 % of all reported results were correctly estimated for formaldehyde, and 88% for melamine.
Therefore for this exercise and the enforcement of the physical tests for consignment of imports under Regulation 284/2011, the OCLs and NRLs performance was the same as can be considered as one unique population in terms of reliability of results.
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2. Introduction
ILC studies are an essential element of laboratory quality assurance and allow individual laboratories to compare their analytical results with those from other laboratories while providing them objective standards to perform against.
It is one of the core duties of the EU Reference Laboratories to organize interlaboratory comparisons, as is stated in Regulation (EC) No 882/2004 of the European Parliament and of the Council [6].
In accordance with the above requirements the European Reference Laboratory for Food Contact Materials (EURL-FCM) organised in 2011-2012 interlaboratory comparison tests for the network of appointed National Reference Laboratories (NRLs).
3. Scope
The scope of this ILC was to test the competence of the appointed NRLs to analyse formaldehyde and melamine from melamine kitchenware into migration solutions of 3% acetic acid as acidic simulant according to Regulation 10/2011. The different concentration levels were obtained by dilution/ spiking from real melamine kitchenware migration solutions.
The purpose of the exercise was 2-fold
Demonstration of the continued capacity of NRLs and guests to perform adequately the measurement of formaldehyde from a migration solution in the context of support to Regulation (EU) No 284/2011 for melamine kitchenware.
Demonstration and provision to the accreditation body of the third line control for the accreditation of NRLs and OCLs for the method for formaldehyde.
An additional optional scope for this ILC only for volunteer NRLs was to quantify concentration of formaldehyde migrated from kitchen utensils (spoons) into 3% acetic acid food simulant. Melamine spoon samples were used to carry out the migration exercise.
The assessment of the measurement results was undertaken on the basis of requirements laid down in international standards and guidelines [1-5, 7].
4. Time frame
The ILC01 2012 was launched in January 2012. Invitation letters were sent to the laboratories on 20th January 2012 (Annex 1). Laboratories were invited to fill in a letter of confirmation of their participation (Annex 2).
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The samples were prepared in December 2011. Homogeneity tests were also run in December 2011. The results from homogeneity test were accepted as time zero for stability test.
The samples were dispatched to participants on 8th February 2012, together with the letters accompanying the samples (Annex 3) and a format for the compilation of results to be eventually sent in non-electronic format (Annex 5). Electronic ProLab files, where the result should be inserted, were sent to the participants by e-mail on 8th February 2012.The participants were asked to compile a letter of confirmation of the receipt of the samples (Annex 4).
The deadline for reporting has been set to 16th March 2012.
5. Test materials 5.1 Preparation
The preparation of the test materials was done by the EURL-FCM laboratory.
The migration solutions were obtained after migration experiment immersing melamine kitchenware (e.g. a batch of spoons) in 3% acetic acid for 2 hours at 70 °C. The three levels of concentrations were obtained by dilution/spiking of the original migration solution in order to obtain more reliable data of the precision and reproducibility for the concentration range under, around and above the permitted limit for formaldehyde (15 mg/kg) and melamine (2.5 mg/kg), where the decision should be made by the Competent Authorities.
Additionally, 3 spoon samples were dispatched to volunteer NRLs for a formaldehyde migration exercise (Table 1).
Table 1. Test materials
5.2 Homogeneity assessment
The samples were tested for homogeneity by the EURL laboratory. Ten randomly selected test specimens for each sample (F&M01, F&M02 and F&M03) were analysed in duplicate for formaldehyde and melamine using the CEN 13130-23 chromotropic acid method [8] and CEN 13130-27 [9] respectively. The homogeneity of the migration solutions matrices was evaluated by the ProLab Software [10] according to IUPAC International Harmonized Protocol [2], F-test and to the method proposed in the ISO 13528 [1]. The results together with their statistical evaluation are given in Annex 6. All solutions showed sufficient homogeneity for the target standard deviation. The batch of
Exercise Name Sample
F&M01 1 bottle of 3% acetic acid migration solution at level 1
F&M02 1 bottle of 3% acetic acid migration solution at level 2
F&M03 1 bottle of 3% acetic acid migration solution at level 3
ILC
01
2012
F&M04 3 spoon samples for formaldehyde migration exercise (NRLs ONLY)
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spoons used for migration exercise was also analysed for homogeneity. The results showed that the batch of spoons did not pass the homogeneity to allow EURL-FCM to allocate the z-scores to laboratories. This confirms that for articles that are grossly non-compliant, the intrinsic homogeneity of objects within a batch is already very low.
5.3 Stability test
Randomly selected specimens for each sample (F&M01, F&M02, and F&M03) were stored at 3 different temperature conditions (5 ºC, 20 °C and 40 ºC). The test samples were monitored for stability by the EURL laboratory from the date of preparation (December 2011) and homogeneity assessment to the closing of the ILC01 2012 (March 2012). Stability was evaluated as described in ISO GUIDE 35:2006 [4]. No significant trend was observed for the test samples at all temperature conditions i.e. 5 ºC, 20 °C and 40 ºC (Annex 7).
5.4 Distribution
The sample kits were dispatched to the participants by the EURL-FCM on 8th February 2012. Each participant received:
a) The box containing the test materials;
b) The accompanying letters with instructions on samples handling, analysis and reporting of results (Annex 3);
c) The receipt form to confirm the samples arrival (Annex 4);
d) The form for reporting the result in non-electronic format (Annex 5).
6. Instructions to participants
Detailed instructions were given to all participants in the letters that accompanied the samples (Annex 3). Laboratories were asked to report 4 results for each concentration level and 2 results for each spoon. Participants were asked to follow their own procedures and to indicate sample preparation method – CR-chromotropic acid, AA-acetyl acetone, 2,4DNPH-2,4 dinitrophenylhydrazine or other, and instrumental method of analysis – UV-VIS, HPLC-DAD, LC-MS or other. The results had to be reported using the unit of measure indicated in the instruction letter. The results were reported in a specific form sent to the participants in hard copy and electronic format (Annex 5).
7. Assigned values
The assigned values from the migration solutions were established as the robust mean values (for each level of concentrations) which came from the participants test results and obtained from robust statistics using the ProLab software [10].
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8. Target standard deviation
The value of target standard deviation (σp) determines the limits of satisfactory performance in ILC test. It should be set as a value that reflects best practice for the analysis in question. The standard deviation of the reproducibility found in the collaborative trials is generally considered as an appropriate indicator of the best agreement that can be obtained between laboratories. However, it is not applicable to all cases. In the absence of appropriate collaborative trial data, σp could be derived from the appropriate form of the modified Horwitz equation [5]. For all samples of this ILC01 2012 exercise the target standard deviation was set to the calculated by Horwitz formula.
9. Evaluation of results 9.1 General observations
There were 70 participants to whom samples were dispatched (EURL, 27 NRLs + 42 national control laboratories from Belgium, France, Germany, Italy, Poland, Slovenia, Spain and United Kingdom), 66 of which submitted results. Out of the submitted results 62 submitted for formaldehyde, 27 had reported only formaldehyde (not both formaldehyde and melamine as requested), and 4 laboratories reported only for melamine and gave no results for formaldehyde. 35 laboratories submitted as requested results both for formaldehyde and melamine. The overall level of participation in the exercise was therefore 94% in total, of which 88.5% for formaldehyde, 56% for melamine and 50% for both substances under test.
9.2 Statistical evaluation of results 9.2.1. Determination of the consensus value
The statistical evaluation of the results was performed using the ProLab software [10] according to Q/Hampel estimator (DIN 38402 A45) [3]
9.2.2. Scores and evaluation criteria
Individual laboratory performance was expressed in terms of z-scores (z) in accordance with ISO 13528 [1] and the International Harmonised Protocol [2]:
p
assignedlab Xxz
σ)( −
= ,
where:
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x lab is the measurement result reported by a participant;
X assigned is the assigned value;
σ p is the target standard deviation for proficiency assessment .
The z- scores can be interpreted as follow:
|z|≤2 satisfactory result;
2<|z|≤3 questionable result;
|z|>3 unsatisfactory result.
9.3 Laboratory results and scores
The summary of the laboratories’ results for formaldehyde and melamine with their robust repeatability standard deviations and robust reproducibility standard deviations was calculated according to Q/Hampel algorithm (ISO 20612:2007 [11] and DIN 38402 A45 [3] ). This was done by the ProLab software as well as assigned values and target standard deviation of the ILC and are reported in Tables 2-3 and Figures 1-6. The summary of the calculated z-scores are reported in Tables 4 and 5, while Figures 7-12 present graphs of the calculated by ProLab z-scores with the tolerance limit z = 2.
Table 2. Summary of results for formaldehyde calculated according to DIN 38402 A45 F&M01 F&M02 F&M03
Method DIN 38402 A45 Robust Mean = Assigned value , mg/kg 9.12 18.85 229.45 Robust Repeatability s.d., mg/kg 0.11 0.21 2.48 Robust Reproducibility s.d., mg/kg 1.10 2.18 38.06 Rel. target s.d., % 11.47 10.28 7.06 Rel. Reproducibility s.d., % 12.02 11.54 16.59 Rel. Repeatability s.d., % 1.23 1.11 1.08 Lower limit of tolerance, mg/kg 7.03 14.97 197.05 Upper limit of tolerance, mg/kg 11.22 22.73 261.84 No. of results 62 62 62
Table 3. Summary of results for melamine calculated according to DIN 38402 A45 F&M01 F&M02 F&M03
Method DIN 38402 A45 Robust Mean = Assigned value , mg/kg 0.25 2.39 3.96 Robust Repeatability s.d., mg/kg 0.01 0.06 0.09 Robust Reproducibility s.d., mg/kg 0.05 0.33 0.77 Rel. target s.d., % 19.68 14.03 13.01 Rel. Reproducibility s.d., % 18.93 13.69 19.43 Rel. Repeatability s.d., % 3.53 2.37 2.28 Lower limit of tolerance, mg/kg 0.15 1.72 2.93 Upper limit of tolerance, mg/kg 0.35 3.06 4.99 No. of results 36 39 39
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ProL
ab 2
010
Labo
rato
ry
LC0032
LC0004
LC0108
LC0060
LC0048
LC0043
LC0018
LC0101
LC0103
LC0006
LC0034
LC0020
LC0029
LC0105
LC0027
LC0066
LC0041
LC0011
LC0095
LC0075
LC0039
LC0003
LC0067
LC0007
LC0106
LC0016
LC0040
LC0050
LC0073
LC0089
LC0044
LC0061
LC0035
LC0049
LC0077
LC0052
LC0037
LC0038
LC0056
LC0010
LC0098
LC0110
LC0074
LC0111
LC0090
LC0025
LC0033
LC0031
LC0080
LC0076
LC0082
LC0005
LC0107
LC0064
LC0017
LC0078
LC0104
LC0013
LC0093
LC0100
LC0109
LC0102
mg/kg18 17 16 15 14 13 12 11 10 9 8 7 6
E
E
EE
E
E
E
Sam
ple:
F&M
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easu
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IN 3
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abor
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Ass
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piric
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Assign
ed va
lue
Mean
Lim
it of
tole
ranc
e
Lim
it of
tole
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e
Figure 1. Summary graph of the laboratory’s test results for formaldehyde (F&M01)
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ProL
ab 2
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Labo
rato
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LC0032
LC0004
LC0060
LC0018
LC0043
LC0034
LC0103
LC0020
LC0048
LC0027
LC0029
LC0056
LC0006
LC0106
LC0011
LC0077
LC0105
LC0066
LC0039
LC0108
LC0075
LC0067
LC0037
LC0016
LC0095
LC0040
LC0101
LC0010
LC0041
LC0007
LC0003
LC0073
LC0038
LC0035
LC0061
LC0044
LC0089
LC0025
LC0049
LC0111
LC0110
LC0033
LC0098
LC0052
LC0080
LC0076
LC0107
LC0074
LC0090
LC0031
LC0005
LC0064
LC0050
LC0017
LC0104
LC0078
LC0082
LC0100
LC0013
LC0109
LC0093
LC0102
mg/kg30 28 26 24 22 20 18 16 14 12
E
E
E
EE
E
E
Sam
ple:
F&M
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easu
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:Fo
rmal
dehy
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IN 3
8402
A45
No.
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abor
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62
Ass
igne
d va
lue:
18.8
499
mg/
kg (E
mpi
rical
val
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Rel
. tar
get s
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orw
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Lim
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kg
(|Z s
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Assign
ed va
lue
Mean
Lim
it of
tole
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e
Lim
it of
tole
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e
Figure 2. Summary graph of the laboratory’s test results for formaldehyde (F&M02)
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ProL
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LC0007
LC0066
LC0004
LC0061
LC0078
LC0040
LC0064
LC0067
LC0106
LC0016
LC0111
LC0033
LC0017
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LC0098
LC0041
LC0011
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LC0107
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LC0035
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LC0075
LC0076
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LC0031
LC0103
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LC0003
LC0101
LC0056
LC0043
LC0050
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LC0034
LC0104
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LC0090
LC0005
LC0080
LC0095
LC0025
LC0020
mg/kg350
300
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200
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Sam
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abor
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Ass
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229.
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mpi
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Assign
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Mean
Lim
it of
tole
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e
Lim
it of
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Figure 3. Summary graph of the laboratory’s test results for formaldehyde (F&M03)
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LC0027
LC0034
LC0044
LC0035
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LC0098
LC0018
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LC0067
LC0077
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LC0060
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LC0038
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mg/kg1
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oler
ance
:0.
1531
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it of
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e
Figure 4. Summary graph of the laboratory’s test results for melamine (F&M01)
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ProL
ab 2
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rato
ry
LC0034
LC0035
LC0027
LC0006
LC0104
LC0094
LC0093
LC0020
LC0007
LC0082
LC0044
LC0002
LC0039
LC0038
LC0040
LC0060
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LC0098
LC0067
LC0018
LC0077
LC0061
LC0107
LC0075
LC0033
LC0041
LC0016
LC0073
LC0099
LC0078
LC0066
LC0017
LC0050
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LC0032
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7.5 7
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66 m
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(Em
piric
al v
alue
)R
el. t
arge
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.:14
.03%
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witz
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%Li
mits
of t
oler
ance
:1.
7167
- 3.
0564
mg/
kg
(|Z s
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Assign
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lue
Mean
Lim
it of
tole
ranc
e
Lim
it of
tole
ranc
e
Figure 5. Summary graph of the laboratory’s test results for melamine (F&M02)
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ProL
ab 2
010
Labo
rato
ry
LC0034
LC0035
LC0044
LC0111
LC0027
LC0006
LC0002
LC0094
LC0104
LC0020
LC0007
LC0082
LC0040
LC0018
LC0093
LC0039
LC0061
LC0067
LC0075
LC0050
LC0078
LC0041
LC0033
LC0073
LC0029
LC0016
LC0032
LC0099
LC0013
LC0066
LC0110
LC0077
LC0017
LC0038
LC0060
LC0098
LC0090
LC0107
LC0074
mg/kg10 9.5 9
8.5 8
7.5 7
6.5 6
5.5 5
4.5 4
3.5 3
2.5 2
E
E
E
E
Sam
ple:
F&M
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easu
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:M
elam
ine
Met
hod:
DIN
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02 A
45N
o. o
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orat
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Ass
igne
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lue:
3.95
79 m
g/kg
(Em
piric
al v
alue
)R
el. t
arge
t s.d
.:13
.01%
(Hor
witz
func
tion)
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. rep
eata
bilit
y s.
d.:
2.28
%Li
mits
of t
oler
ance
:2.
9284
- 4.
9874
mg/
kg
(|Z s
core
| < 2
.00)
Assign
ed va
lue
Mean
Lim
it of
tole
ranc
e
Lim
it of
tole
ranc
e
Figure 6. Summary graph of the laboratory’s test results for melamine (F&M03)
EURL – FCM ILC01 2012- Formaldehyde and melamine in food contact migration solution
17
Table 4. Laboratories’ z-scores for formaldehyde
Laboratory Code
F&M01 F&M02 F&M03 Laborator
y Code F&M01 F&M02 F&M03
LC0003 -0.380 -0.129 1.161 LC0056 0.334 -0.753 1.204 LC0004 -1.814 -2.154 -8.997 LC0060 -1.477 -1.804 0.013 LC0005 0.838 0.929 2.812 LC0061 0.133 0.123 -6.622 LC0006 -1.026 -0.696 2.596 LC0064 1.041 1.056 -2.359 LC0007 -0.304 -0.142 -12.408 LC0066 -0.562 -0.494 -9.507 LC0010 0.336 -0.168 0.210 LC0067 -0.342 -0.431 -2.215 LC0011 -0.548 -0.658 -1.875 LC0073 0.050 -0.052 -1.046 LC0013 2.193 2.257 -0.708 LC0074 0.468 0.847 0.446 LC0016 -0.194 -0.338 -2.117 LC0075 -0.500 -0.439 -0.583 LC0017 1.108 1.102 -1.945 LC0076 0.645 0.660 -0.431 LC0018 -1.315 -1.715 -0.364 LC0077 0.250 -0.593 0.061 LC0020 -0.858 -1.122 6.563 LC0078 1.842 1.264 -4.303 LC0025 0.599 0.322 4.004 LC0080 0.635 0.626 2.884 LC0027 -0.586 -1.025 0.946 LC0082 0.709 1.566 0.821 LC0029 -0.660 -0.944 0.488 LC0089 0.104 0.172 -1.281 LC0031 0.623 0.903 0.990 LC0090 0.520 0.868 2.648 LC0032 -2.516 -2.848 -0.617 LC0093 2.417 2.947 2.124 LC0033 0.609 0.507 -2.047 LC0095 -0.502 -0.329 3.695 LC0034 -0.971 -1.447 2.152 LC0098 0.456 0.568 -1.923 LC0035 0.186 0.034 -1.100 LC0100 2.998 2.142 0.785 LC0037 0.286 -0.383 -0.386 LC0101 -1.080 -0.178 1.193 LC0038 0.286 -0.035 1.140 LC0102 8.218 4.793 -1.686 LC0039 -0.457 -0.488 0.425 LC0103 -1.067 -1.359 0.994 LC0040 0.002 -0.206 -3.346 LC0104 2.033 1.109 2.195 LC0041 -0.551 -0.151 -1.898 LC0105 -0.619 -0.542 0.219 LC0043 -1.339 -1.512 1.231 LC0106 -0.304 -0.673 -2.129 LC0044 0.121 0.129 2.442 LC0107 0.910 0.838 -1.585 LC0048 -1.408 -1.109 0.899 LC0108 -1.695 -0.451 0.775 LC0049 0.243 0.357 -1.935 LC0109 3.550 2.323 -0.679 LC0050 0.026 1.058 1.518 LC0110 0.456 0.477 0.420 LC0052 0.260 0.613 -0.352 LC0111 0.508 0.459 -2.065
EURL – FCM ILC01 2012- Formaldehyde and melamine in food contact migration solution
18
Table 5. Laboratories’ z-scores for melamine
Laboratory Code
F&M01 F&M02 F&M03
LC0002 0.152 -0.370 -1.366 LC0006 -0.955 -1.378 -1.424 LC0007 -0.452 -0.624 -0.652 LC0013 -0.699 0.903 1.106 LC0016 0.403 0.480 0.349 LC0017 - 0.801 1.544 LC0018 -0.170 0.053 -0.580 LC0020 -0.236 -0.647 -1.035 LC0027 -2.867 -1.400 -1.623 LC0029 0.313 1.331 0.286 LC0032 1.153 2.317 1.024 LC0033 -0.075 0.406 0.092 LC0034 -2.616 -2.490 -2.988 LC0035 -1.222 -1.500 -1.940 LC0038 0.504 -0.318 1.631 LC0039 -0.402 -0.326 -0.462 LC0040 -0.518 -0.318 -0.588 LC0041 2.224 0.464 0.052 LC0044 -1.308 -0.378 -1.866 LC0050 7.700 0.898 -0.064 LC0060 0.182 -0.232 1.734 LC0061 0.001 0.077 -0.404 LC0066 1.359 0.645 1.349 LC0067 0.051 0.010 -0.176 LC0073 0.303 0.488 0.179 LC0074 67.982 13.909 10.306 LC0075 - 0.339 -0.112 LC0077 0.051 0.070 1.485 LC0078 0.605 0.592 -0.015 LC0082 -0.301 -0.579 -0.627 LC0090 1.973 2.261 2.175 LC0093 1.269 -0.655 -0.504 LC0094 -0.050 -0.751 -1.307 LC0098 -0.200 -0.102 1.981 LC0099 1.812 0.495 1.024 LC0104 -0.804 -1.236 -1.060 LC0107 -0.146 0.143 2.680 LC0110 - 1.234 1.442 LC0111 -0.251 -0.117 -1.647
EURL – FCM ILC01 2012- Formaldehyde and melamine in food contact migration solution
19
ProL
ab 2
010
Labo
rato
ry
LC0032
LC0004
LC0108
LC0060
LC0048
LC0043
LC0018
LC0101
LC0103
LC0006
LC0034
LC0020
LC0029
LC0105
LC0027
LC0066
LC0041
LC0011
LC0095
LC0075
LC0039
LC0003
LC0067
LC0007
LC0106
LC0016
LC0040
LC0050
LC0073
LC0089
LC0044
LC0061
LC0035
LC0049
LC0077
LC0052
LC0037
LC0038
LC0056
LC0010
LC0098
LC0110
LC0074
LC0111
LC0090
LC0025
LC0033
LC0031
LC0080
LC0076
LC0082
LC0005
LC0107
LC0064
LC0017
LC0078
LC0104
LC0013
LC0093
LC0100
LC0109
LC0102
Z score
8 6 4 2 0 -2
E
EE
E
E
E
E
Sam
ple:
F&M
01M
easu
rand
:Fo
rmal
dehy
deM
etho
d:D
IN 3
8402
A45
No.
of l
abor
ator
ies:
62
Ass
igne
d va
lue:
9.12
31 m
g/kg
(Em
piric
al v
alue
)R
el. t
arge
t s.d
.:11
.47%
(Hor
witz
func
tion)
Rel
. rep
eata
bilit
y s.
d.:
1.23
%Li
mits
of t
oler
ance
:7.
0304
- 11
.215
8 m
g/kg
(|Z
sco
re| <
2.0
0)
Lim
it of
tole
ranc
e
Lim
it of
tole
ranc
e
Figure 7. Summary graph of the laboratory’s z-scores for formaldehyde (F&M01)
EURL – FCM ILC01 2012- Formaldehyde and melamine in food contact migration solution
20
ProL
ab 2
010
Labo
rato
ry
LC0032
LC0004
LC0060
LC0018
LC0043
LC0034
LC0103
LC0020
LC0048
LC0027
LC0029
LC0056
LC0006
LC0106
LC0011
LC0077
LC0105
LC0066
LC0039
LC0108
LC0075
LC0067
LC0037
LC0016
LC0095
LC0040
LC0101
LC0010
LC0041
LC0007
LC0003
LC0073
LC0038
LC0035
LC0061
LC0044
LC0089
LC0025
LC0049
LC0111
LC0110
LC0033
LC0098
LC0052
LC0080
LC0076
LC0107
LC0074
LC0090
LC0031
LC0005
LC0064
LC0050
LC0017
LC0104
LC0078
LC0082
LC0100
LC0013
LC0109
LC0093
LC0102
Z score6 4 2 0 -2
EE
EE
E
E
E
Sam
ple:
F&M
02M
easu
rand
:Fo
rmal
dehy
deM
etho
d:D
IN 3
8402
A45
No.
of l
abor
ator
ies:
62
Ass
igne
d va
lue:
18.8
499
mg/
kg (E
mpi
rical
val
ue)
Rel
. tar
get s
.d.:
10.2
8% (H
orw
itz fu
nctio
n)R
el. r
epea
tabi
lity
s.d.
:1.
11%
Lim
its o
f tol
eran
ce:
14.9
734
- 22.
7265
mg/
kg
(|Z s
core
| < 2
.00)
Lim
it of
tole
ranc
e
Lim
it of
tole
ranc
e
Figure 8. Summary graph of the laboratory’s z-scores for formaldehyde (F&M02)
EURL – FCM ILC01 2012- Formaldehyde and melamine in food contact migration solution
21
ProL
ab 2
010
Labo
rato
ry
LC0007
LC0066
LC0004
LC0061
LC0078
LC0040
LC0064
LC0067
LC0106
LC0016
LC0111
LC0033
LC0017
LC0049
LC0098
LC0041
LC0011
LC0102
LC0107
LC0089
LC0035
LC0073
LC0013
LC0109
LC0032
LC0075
LC0076
LC0037
LC0018
LC0052
LC0060
LC0077
LC0010
LC0105
LC0110
LC0039
LC0074
LC0029
LC0108
LC0100
LC0082
LC0048
LC0027
LC0031
LC0103
LC0038
LC0003
LC0101
LC0056
LC0043
LC0050
LC0093
LC0034
LC0104
LC0044
LC0006
LC0090
LC0005
LC0080
LC0095
LC0025
LC0020
Z score
6 4 2 0 -2 -4 -6 -8 -10
-12
EE
EE
EE
EE
EE
EE
EE
EE
EE
EE
EE
E
Sam
ple:
F&M
03M
easu
rand
:Fo
rmal
dehy
deM
etho
d:D
IN 3
8402
A45
No.
of l
abor
ator
ies:
62
Ass
igne
d va
lue:
229.
4457
mg/
kg (E
mpi
rical
val
ue)
Rel
. tar
get s
.d.:
7.06
% (H
orw
itz fu
nctio
n)R
el. r
epea
tabi
lity
s.d.
:1.
08%
Lim
its o
f tol
eran
ce:
197.
0515
- 26
1.83
99 m
g/kg
(|Z
sco
re| <
2.0
0)
Lim
it of
tole
ranc
e
Lim
it of
tole
ranc
e
Figure 9. Summary graph of the laboratory’s z-scores for formaldehyde (F&M03)
EURL – FCM ILC01 2012- Formaldehyde and melamine in food contact migration solution
22
ProL
ab 2
010
Labo
rato
ry
LC0027
LC0034
LC0044
LC0035
LC0006
LC0104
LC0013
LC0040
LC0007
LC0039
LC0082
LC0111
LC0020
LC0098
LC0018
LC0107
LC0033
LC0094
LC0061
LC0067
LC0077
LC0002
LC0060
LC0073
LC0029
LC0016
LC0038
LC0078
LC0032
LC0093
LC0066
LC0099
LC0090
LC0041
LC0050
LC0074
Z score10 8 6 4 2 0 -2 -4
EE
E
E
Sam
ple:
F&M
01M
easu
rand
:M
elam
ine
Met
hod:
DIN
384
02 A
45N
o. o
f lab
orat
orie
s:36
Ass
igne
d va
lue:
0.25
25 m
g/kg
(Em
piric
al v
alue
)R
el. t
arge
t s.d
.:19
.68%
(Hor
witz
func
tion)
Rel
. rep
eata
bilit
y s.
d.:
3.53
%Li
mits
of t
oler
ance
:0.
1531
- 0.
3518
mg/
kg
(|Z s
core
| < 2
.00)
Lim
it of
tole
ranc
e
Lim
it of
tole
ranc
e
Figure 10. Summary graph of the laboratory’s z-scores for melamine (F&M01)
EURL – FCM ILC01 2012- Formaldehyde and melamine in food contact migration solution
23
ProL
ab 2
010
Labo
rato
ry
LC0034
LC0035
LC0027
LC0006
LC0104
LC0094
LC0093
LC0020
LC0007
LC0082
LC0044
LC0002
LC0039
LC0038
LC0040
LC0060
LC0111
LC0098
LC0067
LC0018
LC0077
LC0061
LC0107
LC0075
LC0033
LC0041
LC0016
LC0073
LC0099
LC0078
LC0066
LC0017
LC0050
LC0013
LC0110
LC0029
LC0090
LC0032
LC0074
Z score10 8 6 4 2 0 -2 -4
E
EE
Sam
ple:
F&M
02M
easu
rand
:M
elam
ine
Met
hod:
DIN
384
02 A
45N
o. o
f lab
orat
orie
s:39
Ass
igne
d va
lue:
2.38
66 m
g/kg
(Em
piric
al v
alue
)R
el. t
arge
t s.d
.:14
.03%
(Hor
witz
func
tion)
Rel
. rep
eata
bilit
y s.
d.:
2.37
%Li
mits
of t
oler
ance
:1.
7167
- 3.
0564
mg/
kg
(|Z s
core
| < 2
.00)
Lim
it of
tole
ranc
e
Lim
it of
tole
ranc
e
Figure 11. Summary graph of the laboratory’s z-scores for melamine (F&M02)
EURL – FCM ILC01 2012- Formaldehyde and melamine in food contact migration solution
24
ProL
ab 2
010
Labo
rato
ry
LC0034
LC0035
LC0044
LC0111
LC0027
LC0006
LC0002
LC0094
LC0104
LC0020
LC0007
LC0082
LC0040
LC0018
LC0093
LC0039
LC0061
LC0067
LC0075
LC0050
LC0078
LC0041
LC0033
LC0073
LC0029
LC0016
LC0032
LC0099
LC0013
LC0066
LC0110
LC0077
LC0017
LC0038
LC0060
LC0098
LC0090
LC0107
LC0074
Z score10 8 6 4 2 0 -2 -4
E
E
E
ES
ampl
e:F&
M03
Mea
sura
nd:
Mel
amin
eM
etho
d:D
IN 3
8402
A45
No.
of l
abor
ator
ies:
39
Ass
igne
d va
lue:
3.95
79 m
g/kg
(Em
piric
al v
alue
)R
el. t
arge
t s.d
.:13
.01%
(Hor
witz
func
tion)
Rel
. rep
eata
bilit
y s.
d.:
2.28
%Li
mits
of t
oler
ance
:2.
9284
- 4.
9874
mg/
kg
(|Z s
core
| < 2
.00)
Lim
it of
tole
ranc
e
Lim
it of
tole
ranc
e
Figure 12. Summary graph of the laboratory’s z-scores for melamine (F&M03)
EURL – FCM ILC01 2012- Formaldehyde and melamine in food contact migration solution
25
10. Migration exercise
In addition to migration solution samples, 19 volunteer NRLs received three melamine spoons which they tested for migration of formaldehyde into 3% acetic acid.
Participants received the corresponding standard operation procedure to carry out the test on the articles (Annex 3).
Participating laboratories were informed that the batch of the articles came from the market and released non compliant levels of formaldehyde.
EURL-FCM performed the homogeneity test on three consecutive migrations from the spoons. All solutions showed different level of heterogeneity in particular the second and the third migrations. For this reason the EURL-FCM asked to participants to quantify formaldehyde in the first migration solution and left them free to quantify the concentrations of formaldehyde also in the second and third migration solutions.
NRLs were asked to report two results of the resulting concentration of formaldehyde from the migration solution for each spoon, and to also report the volume of simulant used1 to perform the test and an estimation of the contact surface area.
The data were analysed statistically using ProLab and the robust mean was calculated by Q/Hampel algorithm (DIN 38402 A45) [3] and reported in Figure13. Due to insufficient homogeneity of the spoons themselves, the z-scores for this part of exercise were not allocated.
The data compared are reported in Table 6. In Figure 14 the concentration of formaldehyde from first, second and third migration solution obtained from migration are presented to evaluate possible trend in the release of formaldehyde along the migration exposure. Any significant trend was observed.
1 Excerpt of Regulation EU 10/2011[12]: “for materials and articles for which it is impracticable to estimate the relationship between the surface area and the quantity of food in contact therewith, for example due to their shape or use, the migration is calculated using the conventional surface area/volume conversion factor of 6 dm2/kg.”.
26
Table 6. Summary results from migration exercise
FIRST MIGRATION
Laboratory code Sample
Formaldehyde in migration
solution [mg/L]
Volume of migration
solution [L]
Formaldehyde in migration solution [mg]
Contact surface [dm2]
Formaldehyde (based on individual surface estimation)
[mg/dm2]
Formaldehyde (based on
surface robust mean)
[mg/dm2]
Formaldehyde (based on
individual surface estimation) by using S/V* 6
dm2/kg [mg/kg]
Formaldehyde (based on surface robust mean, 1.52)
by using S/V* 6 dm2/kg [mg/kg]
1st Spoon A 181.52 0.590 107.10 77.61 70.23 465.63 421.40 1st Spoon B 187.51 0.590 110.63 80.17 72.55 480.99 435.30 2nd Spoon A 188.59 0.590 111.27 80.63 72.97 483.77 437.82 2nd Spoon B 188.53 0.590 111.23 80.60 72.95 483.63 437.68 3rd Spoon A 122.71 0.590 72.40 52.46 47.48 314.77 284.87
LC0013
3rd Spoon B 123.73 0.590 73.00
1.38
52.90 47.88 317.40 287.25 1st Spoon A 64.07 0.600 38.44 - 25.21 - 151.26 1st Spoon B 64.02 0.600 38.41 - 25.19 - 151.14 2nd Spoon A 70.34 0.600 42.20 - 27.68 - 166.06 2nd Spoon B 70.59 0.600 42.35 - 27.78 - 166.65 3rd Spoon A 78.54 0.600 47.12 - 30.90 - 185.42
LC0017
3rd Spoon B 78.85 0.600 47.31
-
- 31.03 - 186.16 1st Spoon A 64.05 0.891 57.06 40.02 37.42 240.10 224.53 1st Spoon B 63.24 0.891 56.34 39.51 36.95 237.05 221.67 2nd Spoon A 54.84 0.868 47.61 33.39 31.22 200.34 187.34 2nd Spoon B 55.65 0.868 48.32 33.89 31.69 203.32 190.13 3rd Spoon A 68.72 0.896 61.56 43.17 40.37 259.02 242.22
LC0018
3rd Spoon B 65.20 0.896 58.40
1.43
40.95 38.30 245.73 229.79 1st Spoon A 187.25 0.452 84.64 47.55 55.50 285.29 333.03 1st Spoon B 174.22 0.452 78.75 44.24 51.64 265.44 309.86 2nd Spoon A 245.37 0.450 110.42 62.03 72.41 372.19 434.47 2nd Spoon B 238.80 0.450 107.46 60.37 70.47 362.22 422.83 3rd Spoon A 181.93 0.460 83.69 47.02 54.88 282.10 329.30
LC0027
3rd Spoon B 181.01 0.460 83.27
1.78
46.78 54.61 280.67 327.64 1st Spoon A 20.12 0.660 13.28 7.63 8.71 45.79 52.25 1st Spoon B 20.15 0.660 13.30 7.64 8.72 45.86 52.33 2nd Spoon A 17.80 0.620 11.04 6.34 7.24 38.06 43.42 2nd Spoon B 17.68 0.620 10.96 6.30 7.19 37.80 43.13 3rd Spoon A 16.49 0.650 10.72 6.16 7.03 36.96 42.18
LC0033
3rd Spoon B 16.57 0.650 10.77
1.74
6.19 7.06 37.14 42.38
27
FIRST MIGRATION
Laboratory code Sample
Formaldehyde in migration
solution [mg/L]
Volume of migration
solution [L]
Formaldehyde in migration solution [mg]
Contact surface [dm2]
Formaldehyde (based on individual surface estimation)
[mg/dm2]
Formaldehyde (based on
surface robust mean)
[mg/dm2]
Formaldehyde (based on
individual surface estimation) by using S/V* 6
dm2/kg [mg/kg]
Formaldehyde (based on surface robust mean, 1.52)
by using S/V* 6 dm2/kg [mg/kg]
1st Spoon A 161.30 0.470 75.81 47.09 49.72 282.53 298.30 1st Spoon B 161.10 0.470 75.72 47.03 49.66 282.18 297.93 2nd Spoon A 192.50 0.470 90.48 56.20 59.33 337.17 356.00 2nd Spoon B 191.70 0.470 90.10 55.96 59.09 335.77 354.52 3rd Spoon A 212.40 0.470 99.83 62.00 65.47 372.03 392.80
LC0035
3rd Spoon B 212.70 0.470 99.97
1.61
62.09 65.56 372.56 393.36 1st Spoon A 171.10 0.485 82.98 55.32 54.42 331.93 326.52 1st Spoon B 170.50 0.485 82.69 55.13 54.23 330.77 325.38 2nd Spoon A 136.40 0.496 67.65 45.10 44.37 270.62 266.21 2nd Spoon B 135.20 0.496 67.06 44.71 43.98 268.24 263.86 3rd Spoon A 120.20 0.492 59.14 39.43 38.78 236.55 232.70
LC0037
3rd Spoon B 118.20 0.492 58.15
1.50
38.77 38.14 232.62 228.83 1st Spoon A 210.85 0.500 105.42 63.51 69.14 381.05 414.82 1st Spoon B 211.87 0.500 105.93 63.82 69.47 382.89 416.83 2nd Spoon A 219.80 0.500 109.90 66.21 72.07 397.23 432.44 2nd Spoon B 220.08 0.500 110.04 66.29 72.16 397.73 432.98 3rd Spoon A 214.03 0.500 107.01 64.47 70.18 386.80 421.08
LC0038
3rd Spoon B 212.93 0.500 106.46
1.66
64.13 69.82 384.81 418.91 1st Spoon A 61.06 0.600 36.64 29.55 24.03 177.27 144.16 1st Spoon B - - - - - - - 2nd Spoon A 42.65 0.600 25.59 20.64 16.78 123.82 100.69 2nd Spoon B - - - - - - - 3rd Spoon A 20.94 0.600 12.56 10.13 8.24 60.79 49.44
LC0039
3rd Spoon B - - -
1.24
- - - - 1st Spoon A 115.46 0.530 61.19 30.75 40.13 184.50 240.79 1st Spoon B 115.58 0.530 61.26 30.78 40.17 184.70 241.04 2nd Spoon A 153.77 0.530 81.50 40.95 53.45 245.72 320.68 2nd Spoon B 152.35 0.530 80.75 40.58 52.95 243.45 317.72 3rd Spoon A 149.89 0.530 79.44 39.92 52.10 239.52 312.59
LC0040
3rd Spoon B 150.44 0.530 79.73
1.99
40.07 52.29 240.40 313.73
28
FIRST MIGRATION
Laboratory code Sample
Formaldehyde in migration
solution [mg/L]
Volume of migration
solution [L]
Formaldehyde in migration solution [mg]
Contact surface [dm2]
Formaldehyde (based on individual surface estimation)
[mg/dm2]
Formaldehyde (based on
surface robust mean)
[mg/dm2]
Formaldehyde (based on
individual surface estimation) by using S/V* 6
dm2/kg [mg/kg]
Formaldehyde (based on surface robust mean, 1.52)
by using S/V* 6 dm2/kg [mg/kg]
1st Spoon A 104.85 0.800 83.88 52.43 55.01 314.55 330.05 1st Spoon B 106.13 0.800 84.90 53.07 55.68 318.39 334.08 2nd Spoon A 102.24 0.800 81.79 51.12 53.64 306.72 321.84 2nd Spoon B 102.41 0.800 81.93 51.21 53.73 307.23 322.37 3rd Spoon A 95.59 0.800 76.47 47.80 50.15 286.77 300.90
LC0060
3rd Spoon B 91.54 0.800 73.23
1.60
45.77 48.03 274.62 288.15 1st Spoon A 62.03 0.580 35.98 - 23.59 - 141.56 1st Spoon B 61.60 0.580 35.73 - 23.43 - 140.58 2nd Spoon A 58.67 0.580 34.03 - 22.32 - 133.90 2nd Spoon B 49.59 0.580 28.76 - 18.86 - 113.17 3rd Spoon A 60.45 0.580 35.06 - 22.99 - 137.96
LC0066
3rd Spoon B 73.15 0.580 42.43
-
- 27.82 - 166.94 1st Spoon A 233.70 0.500 116.85 - 76.63 - 459.78 1st Spoon B 233.40 0.500 116.70 - 76.53 - 459.19 2nd Spoon A 193.20 0.500 96.60 - 63.35 - 380.10 2nd Spoon B 195.00 0.500 97.50 - 63.94 - 383.64 3rd Spoon A 123.40 0.500 61.70 - 40.46 - 242.78
LC0067
3rd Spoon B 123.10 0.500 61.55
-
- 40.36 - 242.19 1st Spoon A 149.07 0.500 74.54 43.33 48.88 260.01 293.28 1st Spoon B 154.80 0.500 77.40 45.00 50.76 270.00 304.55 2nd Spoon A 189.20 0.500 94.60 55.00 62.04 330.00 372.23 2nd Spoon B 194.90 0.500 97.45 56.66 63.91 339.94 383.45 3rd Spoon A 177.73 0.500 88.87 51.67 58.28 309.99 349.67
LC0073
3rd Spoon B 183.47 0.500 91.74
1.72
53.33 60.16 320.01 360.96 1st Spoon A 187.79 0.505 94.83 - 62.19 - 373.15 1st Spoon B 203.28 0.505 102.66 - 67.32 - 403.93 2nd Spoon A 85.10 0.490 41.70 - 27.35 - 164.08 2nd Spoon B 91.60 0.490 44.88 - 29.43 - 176.61 3rd Spoon A 128.09 0.495 63.40 - 41.58 - 249.48
LC0077
3rd Spoon B 137.20 0.495 67.91
-
- 44.54 - 267.23
29
FIRST MIGRATION
Laboratory code Sample
Formaldehyde in migration
solution [mg/L]
Volume of migration
solution [L]
Formaldehyde in migration solution [mg]
Contact surface [dm2]
Formaldehyde (based on individual surface estimation)
[mg/dm2]
Formaldehyde (based on
surface robust mean)
[mg/dm2]
Formaldehyde (based on
individual surface estimation) by using S/V* 6
dm2/kg [mg/kg]
Formaldehyde (based on surface robust mean, 1.52)
by using S/V* 6 dm2/kg [mg/kg]
1st Spoon A 112.50 0.510 57.38 - 37.63 - 225.76 1st Spoon B 116.30 0.510 59.31 - 38.90 - 233.39 2nd Spoon A 90.10 0.495 44.60 - 29.25 - 175.49 2nd Spoon B 91.70 0.495 45.39 - 29.77 - 178.61 3rd Spoon A 107.70 0.485 52.23 - 34.26 - 205.53
LC0093
3rd Spoon B 110.90 0.485 53.79
-
- 35.27 - 211.64 1st Spoon A 116.00 0.490 56.84 36.16 37.28 216.95 223.65 1st Spoon B 116.00 0.490 56.84 36.16 37.28 216.95 223.65 2nd Spoon A 109.50 0.490 53.66 34.13 35.19 204.79 211.12 2nd Spoon B 109.50 0.490 53.66 34.13 35.19 204.79 211.12 3rd Spoon A 160.70 0.490 78.74 50.09 51.64 300.55 309.84
LC0098
3rd Spoon B 161.40 0.490 79.09
1.57
50.31 51.86 301.85 311.19 1st Spoon A 110.00 0.600 66.00 47.14 43.28 282.86 259.70 1st Spoon B 108.00 0.600 64.80 46.29 42.50 277.71 254.98 2nd Spoon A 38.20 0.600 22.92 16.37 15.03 98.23 90.19 2nd Spoon B 38.40 0.600 23.04 16.46 15.11 98.74 90.66 3rd Spoon A 114.60 0.600 68.76 49.11 45.09 294.69 270.56
LC0107
3rd Spoon B 115.60 0.600 69.36
1.40
49.54 45.49 297.26 272.92 1st Spoon A 77.99 0.630 49.13 67.31 32.22 403.84 193.33 1st Spoon B 74.70 0.630 47.06 64.47 30.86 386.80 185.18 2nd Spoon A 88.31 0.630 55.64 76.21 36.49 457.28 218.91 2nd Spoon B 85.69 0.630 53.98 73.95 35.40 443.71 212.42 3rd Spoon A 85.65 0.630 53.96 73.92 35.39 443.50 212.32
LC0111
3rd Spoon B 84.48 0.630 53.22
0.73
72.91 34.90 437.44 209.42
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30
ProL
ab 2
010
Labo
rato
ry
LC0033
LC0039
LC0066
LC0017
LC0093
LC0111
LC0107
LC0018
LC0098
LC0077
LC0037
LC0040
LC0060
LC0073
LC0035
LC0027
LC0067
LC0013
LC0038
mg/kg500
450
400
350
300
250
200
150
100 50 0
E
EE
E
EE
E
E
E
E
E
E
EE
E
Sam
ple:
F&M
04M
easu
rand
:Fo
rmal
dehy
deM
etho
d:D
IN 3
8402
A45
No.
of l
abor
ator
ies:
19M
ean:
260.
8407
mg/
kg
Mean
Figure 13. Summary graph of the laboratory’s test results for formaldehyde (F&M04)
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Figure 14. Comparison of the formaldehyde concentration from first, second and third migration ( 1st spoon)
11. Conclusion
An overview of the ILC01 2012 outcome shows that the participation of the laboratories in the ILC01 2012 could be regarded as satisfactory. Sixty six participants (94.3%) reported results out of 70 sent sample kits. Four participants do not report results. Out of the laboratories who reported results, 88.5% reported for formaldehyde, 56% for melamine and 50% for both substances under test.
As this ILC targeted the correct implementation of Regulation 284/2011 on imports which requires the analysis of 10% of the consignments, all reporting laboratories were expected to report at least results for formaldehyde.
Regarding the quantification of formaldehyde and melamine in the migration solutions of kitchenware in 3% acetic acid, this ILC showed that:
For all 66 laboratories comprising of NRLs and OCLs
o For formaldehyde 80 % of all reported results (for all three concentration levels) were properly estimated;
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o For melamine 89 % of all reported results were properly estimated;
For the NRLs-FCM:
o for formaldehyde 79 % of all reported results were correctly calculated;
o for melamine 88 % of all reported results were properly estimated.
Therefore for this exercise and the enforcement of the physical tests for consignment of imports under Regulation 284/2011, the OCLs and NRLs performance was the same as can be considered as one unique population in terms of reliability of results.
The results and z-scores for NRLs were investigated further specifically on formaldehyde for the 62 laboratories who submitted results. The results for F&M01 and F&M02 had 7 of the 62 laboratories (ca. 11%) returning questionable or unsatisfactory results. For the third solution, F&M03, 23 of the 62 laboratories (ca. 37%) returned questionable or unsatisfactory (i.e. z-score higher than 2). The third sample required dilution step before analysis, which could have caused the highest robust reproducibility standard deviation value, so possible reasons were investigated.
The EURL-FCM will therefore follow up with a questionnaire in order to identify the potential processes that led to the questionable or unsatisfactory performance (including how and when diluted, what was the measured concentration and what was the calibration range). This will constitute the first measure (root cause analysis) as prescribed by Eurachem for underperformance. The second measure will be the production of a new blind solution that will be sent to underperforming NRLs and give the opportunity to improve performance.
For melamine, F&M01, F&M02 and F&M03 88% of the laboratories reported satisfactory results.
With regards to the migration experiments, the data highlighted that the release of formaldehyde does not follow a diffusion-led migration as the results between 1st, 2nd and 3rd migration do not decrease steadily and remain somewhat unpredictable. The results confirmed a great variability between kitchen items for the high migrating non compliant articles, indicating a lack of good manufacturing practice in their production.
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12. Acknowledgements The NRLs and guests signed up for this exercise are listed below. NRLs
AUSTRIA Austrian Agency for Health and Food Safety (AGES), Wien
BELGIUM Institute of Public Health, ISSP-LP, Bruxelles
BULGARIA National Centre for Public Health Protection, Sofia
CYPRUS Laboratory for Control of Food Contact Materials and Control of Toys Ministry of Health, State General Laboratory (SGL), Nicosia
CZECH NIPH- NRL for Food Contact Materials and for Articles for children under 3 years old, National Institute of Public Health (SZU’), Praha
DENMARK Department of Food Chemistry, Danish Veterinary and Food Administration, Lystrup
ESTONIA Health Protection Inspectorate - Central Laboratory of Chemistry, Tallinn
FINLAND Finnish Customs Laboratory, Espoo
FRANCE Centre for Energy Material and Packaging - Laboratoire National d'Essais, Trappes Cedex
FRANCE SCL Laboratoire de Bordeaux-Pessac, Pessac
GERMANY Bundesinstitut für Risikobewertung (BFR) (Federal Institute for Risk Assessment), Berlin
GREECE General Chemical State Laboratory, D’ Chemical Service of Athens, Section Laboratory of Articles and Materials in Contact with Foodstuffs, Athens
HUNGARY Central Agricultural Office, Food and Feed Safety Directorate, Food Toxicology National Reference Laboratory, Budapest
HUNGARY Central Agricultural Office, Food and Feed Safety Directorate, National Reference Laboratory for Feed, Budapest
IRELAND Public Analyst Laboratory - Sir Patrick Duns Hospital, Dublin
ITALY Istituto Superiore di Sanità, Laboratorio Esposizione e rischio da materiali, c/o Dipartimento ambiente e connessa prevenzione primaria, Roma
LUXEMBOURG Laboratoire National de Santé, Division du Controle des Denrées Alimentaires, Luxembourg
LATVIA Institute of food Safety, animal Health and Environment (BIOR), Riga
LITHUANIA National Public Health Investigation Centre, Laboratory of Chemistry, Vilnius
POLAND Laboratory of Department of Food and Consumer Articles Research, National Institute of Hygene, Warsaw
PORTUGAL ESB-SE (Portuguese Catholic University - Biotechnology College – Packaging Department), Porto
SLOVAKIA National Reference Centre and Laboratory for material and articles intended to come into contact with food, Regional Public Health Authority In Poprad (RUVZ), Poprad
SLOVENIA National Institute of Public Health of Republic of Slovenia, Department of Sanitary Chemistry, Ljubijana
SPAIN Centro Nacional de Alimentación, Agencia Espanola de Seguridad Alimentaria y Nutrición (AESAN), Madrid
SWEDEN SWEDEN National Food Agency, Science Department, Uppsala
THE NETHERLANDS Food and Consumer Product Safety Authority (VWA), Ministry of Economic Affairs, Agriculture and Innovation, Groningen
UNITED KINGDOM Central Science Laboratory, York GUESTs BELGIUM Agence Federale Pour la Securite Alimentaire, Liege
FRANCE SCL, Oullins Cedex
GERMANY Chemisches und Veterinäruntersuchungsamt Stuttgart, Fellbach
GERMANY CVUA-OWL, Detmold
GERMANY CVUA-RRW, Krefeld
GERMANY Hessisches Landeslabor, Wiesbaden
GERMANY Landesamt für Gesundheit und Verbraucherschutz (LGV), Saarbrücken
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GERMANY Landeshauptstadt Düsseldorf, Der Oberbürgermeister Amt für Verbraucherschutz – Chemische und
Lebensmitteluntersuchung, Düsseldorf
GERMANY Landesuntersuchungsamt, Institut für Lebensmittelchemie Koblenz, Koblenz
GERMANY LAV Sachsen-Anhalt, Fachbereich Lebensmittelsicherheit, Halle
GERMANY Niedersächsisches Landesamt für Verbraucherschutz und Lebensmittelsicherheit,
Institut für Bedaefsgegenstände Lüneburg, Lüneburg
ITALY ASL Varese
ITALY ARPA Calabria, Cosenza
ITALY ARPA Lazio, Roma
ITALY ARPA Liguria, Genova
ITALY ARPA Marche, Pesaro
ITALY ARPA Piemonte – Polo Alimenti, La Loggia
ITALY ARPA Trento, Trento
ITALY ARPA Umbria, Terni
ITALY ARPA Veneto, Verona
ITALY Istituto Zooprofilattico Sperimentale, Lombardia Emilia Romagna, Bologna
ITALY Istituto Zooprofilattico Sperimentale dell'Umbria e delle Marche, Perugia
ITALY Laboratorio di Prevenzione di Milano
ITALY Laboratorio di Sanità Pubblica, Azienda Sanitaria di Firenze
POLAND WSSE, Białystok
POLAND WSSE, Kielce
POLAND WSSE, Lublin
POLAND WSSE, Łódź
POLAND WSSE, Olsztyn
POLAND WSSE, Poznań
POLAND WSSE, Szczecin
POLAND WSSE, Warszawa
SLOVENIA Zavod za Zdravstveno Varstvo Maribor, Maribor
SPAIN Centro Analitico de Inspeccion y Control de Calidad de Comercio Exterior, Madrit
SPAIN CNTA-Laboratorio del Ebro, San Adrian
SPAIN Laboratorio de Salud Publica Alicante
SPAIN Laboratorio de Salud Publica de Telavera de la Reina, Toledo
SWITZERLAND Kantonales Labor Zürich, Zürich
UNITED KINGDOM Worcestershire Scientific Services, Worcester
UNITED KINGDOM Kent Scientific Services, Kent
UNITED KINGDOM West Yorkshire Analytical Services, Leeds
UNITED KINGDOM Public Analyst Scientific Services Ltd., Norwich
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12. References
13. Annexes
Annex 1: Invitation letter to laboratories ILC01 2012
Annex 2: Format for confirmation of participation to ILC01 2012
Annex 3: Letters accompanying the sample ILC01 2012
Annex 4: Letter of confirmation of receipt of ILC01 2012
Annex 5: Form for the compilation of the results in non-electronic format
Annex 6: Results of the homogeneity study
Annex 7: Results of the stability study
[1] ISO 13528:2005; Statistical Methods for Use in Proficiency Testing by Interlaboratory Comparisons
[2] The International Harmonised Protocol for the Proficiency Testing of Analytical Chemistry Laboratories by M. Thompson et al., Pure and Applied Chemistry (2006), 78, 145–196
[3] DIN 38402 A45 Ringversuche zur externen Qualitätskontrolle von Laboratorien
[4] ISO GUIDE 35:2006; Reference materials–General and statistical principles for certification
[5] M. Thompson, Analyst, (2000), 125, 385-386
[6] Regulation (EC) No 882/2004 of the European Parliament and of the Council of 29 April 2004 on official controls performed to ensure the verification of compliance with feed and food law, animal health and animal welfare rules
[7] T. Linsinger et al., Accreditation and Quality Assurance in Analytical Chemistry (2001), 6, 20-25
[8] CEN 13130-23:2005, Determination of formaldehyde and hexamethylenete-tramine in food simulants
[9] CEN 13130-27:2005, Determination of 2,4,6-triamino-1,3,5-triazine in food simulants
[10] ProLab Software – QuoData, Drezden – www.quodata.de
[11] ISO/TS 20612 Water quality – Interlaboratory comparison for proficiency testing of analytical chemistry laboratories
[12] Regulation (EC) No 10/2011 of the European Parliament and the Council of 14 January 2011 on plastic materials and articles intended to come into contact with food
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Annex 1. Invitation letter to laboratories ILC01 2012
EURL – FCM ILC01 2012- Formaldehyde and melamine in food contact migration solution
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Annex 2. Format for confirmation of participation to ILC01 2012
EURL – FCM ILC01 2012- Formaldehyde and melamine in food contact migration solution
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Annex 3. Letters accompanying the sample ILC01 2012
EURL – FCM ILC01 2012- Formaldehyde and melamine in food contact migration solution
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Annex 4. Letter of confirmation of receipt of ILC01 2012
EURL – FCM ILC01 2012- Formaldehyde and melamine in food contact migration solution
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Annex 5. Form for the compilation of the results in non-electronic format
EURL – FCM ILC01 2012- Formaldehyde and melamine in food contact migration solution
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Annex 6. Results of the homogeneity study
Sample Measurand Unit Mean s(analytical) % Mode s(target) HORRAT s(target) %
F-test Check for significant
heterogeneity
ISO 13528 Check for sufficient homogeneity
Harmonized Protocol - test on
significant heterogeneity
Formaldehyde mg/kg 9.53 5.77 1 11.39 OK OK OK F&M01
Melamine mg/kg 0.27 2.77 1 19.51 OK OK OK
Formaldehyde mg/kg 19.62 9.35 1 10.22 OK OK OK F&M02
Melamine mg/kg 2.41 1.90 1 14.01 OK OK OK
Formaldehyde mg/kg 238.86 5.07 1 7.02 OK OK OK F&M03
Melamine mg/kg 4.86 8.79
Horwitz
1 12.61 OK OK OK
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Annex 7. Results of the stability study A)
B) C)
Figure 15. Results of the stability for formaldehyde A) F&M01, B) F&M02 and C)
F&M03
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A)
B)
C)
Figure 16. Results of the stability for melamine A) F&M01, B) F&M02 and C) F&M03
European Commission EUR 25686 – Joint Research Centre – Institute for Health and Consumer Protection Title: Report of the interlaboratory comparison organised by the European Reference Laboratory for Food Contact Material, ILC01 2012- Formaldehyde and Melamine in 3% acetic acid migration solution. Author(s): Giorgia Beldì, Natalia Jakubowska, Oguzhan Yavuz and Catherine Simoneau Luxembourg: Publications Office of the European Union 2012 – 49 pp. – 21.0 x 29.7 cm EUR – Scientific and Technical Research series – ISSN 1831-9424 ISBN 978-92-79-28085-6 doi:10.2788/77358 Abstract This report presents the results of the Inter-laboratory comparison (ILC) organised by the EURL-FCM, Ispra (Italy), which focused on the quantification of formaldehyde and melamine in migration solutions of 3% acetic acid from food contact materials. The test materials used for preparation of the migration solutions were melamine kitchenware (spoons) containing formaldehyde and melamine. The EURL prepared and distributed three concentration levels of migration solution and in addition three melamine kitchen articles (spoons). The general aim of the exercise was to assess the performance of the official control laboratories and consequently the participants were free to use any analytical method of their choice. There were 70 participants to whom samples were dispatched (EURL, 27 NRLs + 42 national control laboratories from Belgium, France, Germany, Italy, Poland, Slovenia, Spain and United Kingdom) and 66 of which submitted results. The assigned values were obtained after applying the robust statistics to the results of the participants. Participants were invited to report 4 results for each concentration level and 2 results for each spoon. The ILC showed that the participation in the ILC was satisfactory regarding the number of the participating laboratories. For formaldehyde 80 % of all reported results were properly estimated, for melamine 89 % of all reported results were properly estimated.
z
As the Commission’s in-house science service, the Joint Research Centre’s mission is to provide EU policies with independent, evidence-based scientific and technical support throughout the whole policy cycle. Working in close cooperation with policy Directorates-General, the JRC addresses key societal challenges while stimulating innovation through developing new standards, methods and tools, and sharing and transferring its know-how to the Member States and international community. Key policy areas include: environment and climate change; energy and transport; agriculture and food security; health and consumer protection; information society and digital agenda; safety and security including nuclear; all supported through a cross-cutting and multi-disciplinary approach.
LB-N
A-25686-E
N-N