The certification of the mass fraction of pesticides in wheat flour : ERM®-BC706.
Date: 2022-11-24
Institutions: Joint Research Centre
Subjects: Community certification, cereal flour, dangerous substance, pesticide, research method, research report

CERTIFICATION REPORT 

 The certification of the mass fraction of 
pesticides in wheat flour: ERM®-BC706 

EUR 30972 EN 

This publication is a Reference Materials report by the Joint Research Centre (JRC), the European Commission’s science and knowledge service. It aims to 
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JRC128302 

EUR 30972 EN 

PDF 

ISBN 978-92-76-46990-2 

ISSN 1831-9424 

doi:10.2760/919535 

Luxembourg: Publications Office of the European Union, 2022 

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Abstract 
This report describes the production of ERM-BC706, a wheat flour material certified for the mass fraction of selected pesticides. The material was 
produced and certified in accordance with ISO 17034:2016 and ISO Guide 35:2017. ERM-BC706 was produced within the scope of ISO 17034 
accreditation. 
The wheat grains originated from Denmark where they were treated with pesticides on the field. Subsequently, the grains were further fortified with 
pesticides, air dried, cryo-milled and homogenised. The CRM is available in glass bottles with screw caps containing at least 45 g of wheat flour. The 
bottles were closed inside a glovebox filled with nitrogen. Afterwards the closed bottles were placed in sachets that were sealed outside the glovebox. The 
minimum amount of sample to be used is 1 g. 
Between-unit homogeneity was quantified and stability during dispatch and storage was assessed in accordance with ISO Guide 35:2017.  
The material was characterised by an inter-laboratory comparison of laboratories of demonstrated competence and adhering to ISO/IEC 17025:2017. 
Technically invalid results were removed but no outlier was eliminated unless a technical reason for the deviation was found. 
Uncertainties of the certified values were calculated in accordance with ISO 17034:2016 and ISO Guide 35:2017 and include uncertainties related to 
possible inhomogeneity, instability and characterisation. 
The material is intended for the quality control and assessment of method performance. As with any reference material, it can be used for establishing 
control charts or validation studies. 
Before release of the CRM, the certification project was subjected to peer-review involving both internal and external experts. 

How to cite this report: B. Sejerøe-Olsen, P. Shegunova, S. Harbeck, J. Seghers, M. E. Poulsen, M. Dabrio, The certification of the mass fraction of  
pesticides in wheat flour: ERM®-BC706, EUR 30972 EN, Publications Office of the European Union, Luxembourg, 2022, ISBN 978-92-76-46990-2, 
doi:10.2760/919535, JRC128302. 

CERTIFICATION REPORT 

The certification of the mass fraction of 
pesticides in wheat flour: ERM®-BC706 

B. Sejerøe-Olsen1, P. Shegunova1, S. Harbeck1,
J. Seghers1, M. E. Poulsen2, M. Dabrio1

1European Commission, Joint Research Centre 
Directorate F – Health, Consumers and Reference Materials 
Geel, Belgium 

2European Union Reference Laboratory for Cereals and Feedingstuff (EURL-CF), 
DTU, Kgs. Lyngby, Denmark 

Disclaimer 

Certain  commercial  equipment,  instruments,  and  materials  are  identified  in  this  paper  to  specify  adequately  the 
experimental procedure. In no case does such identification imply recommendation or endorsement by the European 
Commission, nor does it imply that the material or equipment is necessarily the best available for the purpose.  

Summary 

This report describes the production of ERM-BC706, a  wheat  flour  material certified  for the mass 
fraction  of  selected  pesticides.  The  material  was  produced  and  certified  in  accordance  with  ISO 
17034:2016 [1] and ISO Guide 35:2017 [2]. ERM-BC706 was produced within the scope of ISO 17034 
accreditation. 

The  wheat  grains  originated  from  Denmark  where  they  were  treated  with  pesticides  on  the  field. 
Subsequently,  the  grains  were  further  fortified  with  pesticides,  air  dried,  cryo-milled  and 
homogenised. The CRM is available in glass bottles with screw caps containing at least 45 g of wheat 
flour. The bottles were closed inside a glovebox filled with nitrogen. Afterwards the closed bottles 
were placed in sachets that were sealed outside the glovebox. The minimum amount of sample to be 
used is 1 g. 

Between-unit homogeneity was quantified and stability during dispatch and storage was assessed in 
accordance with ISO Guide 35:2017 [2].  

The material was characterised by an inter-laboratory comparison of laboratories of demonstrated 
competence and adhering to ISO/IEC 17025:2017 [3]. Technically invalid results were removed but 
no outlier was eliminated unless a technical reason for the deviation was found. 

Uncertainties of the certified values were calculated in accordance with ISO 17034:2016 [1] and ISO 
Guide  35:2017  [2]  and  include  uncertainties  related  to  possible  inhomogeneity,  instability  and 
characterisation. 

The material is intended for the quality control and assessment of method performance. As with any 
reference material, it can be used for establishing control charts or validation studies. 

Before  release  of  the  CRM,  the  certification  project  was  subjected  to  peer-review  involving  both 
internal and external experts. 

The following values were assigned: 

Azoxystrobin (CAS RN 131860-33-8) 

Chlormequat2,3) (CAS RN 7003-89-6) 

Chlorpyrifos (CAS RN 2921-88-2) 

Cypermethrin4,5) (CAS RN 52315-07-8) 

Deltamethrin4,6) (CAS RN 52918-63-5) 

Diazinon (CAS RN 333-41-5) 

α-Endosulfan4) (CAS RN 959-98-8) 

β-Endosulfan4) (CAS RN 33213-65-9) 

Endosulfan sulfate4) (CAS RN 1031-07-8) 

Sum of α- and β-endosulfan and endosulfan sulfate 
expressed as endosulfan4,7) 

Fipronil (CAS RN 120068-37-3) 

Fipronil sulfone (CAS RN 120068-36-2) 

1 

Mass Fraction 1) 

Certified value 12) 
[mg/kg] 

Uncertainty 13) 
[mg/kg] 

0.075 

2.1 

2.43 

3.7 

3.8 

0.38 

0.093 

0.27 

0.36 

0.72 

0.42 

0.59 

0.010 

0.4 

0.23 

0.5 

0.7 

0.04 

0.016 

0.04 

0.06 

0.09 

0.04 

0.06 

 
 
Sum of fipronil and fipronil sulfone expressed as fipronil8) 

Glyphosate2) (CAS RN 1071-83-6) 

Imazalil9) (CAS RN 35554-44-0) 

Imidacloprid2) (CAS RN 138261-41-3) 

Linuron2) (CAS RN 330-55-2) 

Malaoxon (CAS RN 1634-78-2) 

Malathion (CAS RN 121-75-5) 

Sum of malathion and malaoxon expressed as malathion10) 

Permethrin11) (CAS RN 52645-53-1) 

Tebuconazole (CAS RN 107534-96-3) 

Thiabendazole2) (CAS RN 148-79-8) 
1) Based on dry mass and corrected for recovery 

0.98 

1.20 

0.23 

0.044 

0.51 

0.0112 

9.7 

9.0 

0.40 

0.041 

0.41 

0.09 

0.19 

0.04 

0.007 

0.06 

0.0015 

1.0 

1.3 

0.07 

0.006 

0.05 

2) As obtained by liquid chromatography/triple quadrupole mass spectrometry 

3) Corresponds to the parameter “Chlormequat (sum of chlormequat and its salts, expressed as chlormequat-chloride)” as listed in 
Commission Regulation (EU) 2020/1565 

4) As obtained by extraction with acetonitrile/water and gas chromatography/triple quadrupole mass spectrometry 

5) Corresponds to the parameter “Cypermethrin (cypermethrin including other mixtures of constituent isomers (sum of isomers))” as 
listed in Commission Regulation (EU) 2017/626 

6) Corresponds to the parameter “Deltamethrin (cis-deltamethrin)” as listed in Commission Regulation (EU) 2018/832 

7)  Corresponds  to  the  parameter  “Endosulfan  (sum  of  alpha-  and  beta-isomers  and  endosulfan-sulphate  expressed  as 
endosulfan)” as listed in Commission Regulation (EU) 310/2011 

8)  Corresponds  to  the  parameter  “Fipronil  (sum  of  fipronil  +  sulfone  metabolite  (MB46136)  expressed  as  fipronil)”  as  listed  in 
Commission Regulation (EU) 2019/1792 

9) Corresponds to the parameter “Imazalil (any ratio of constituent isomers)” as listed in Commission Regulation (EU) 2020/856 

10) Corresponds to the parameter “Malathion (sum of malathion and malaoxon expressed as malathion)” as listed in Commission 
Regulation (EU) 2015/399 

11) Corresponds to the parameter “Permethrin (sum of isomers)” as listed in Commission Regulation (EU) 2017/623 

12) Certified values are values that fulfil the highest standards of accuracy. The given value(s) represent(s) the unweighted mean 
value of the means of accepted sets of data, each set being obtained in a different laboratory and/or with a different method 
of determination. The certified value and its uncertainty are traceable to the International System of Units (SI). 

13) The uncertainty of the certified value is the expanded uncertainty with a coverage factor k = 2 corresponding to a level of 
confidence of about 95 % estimated in accordance with ISO 17034:2016 and ISO Guide 35:2017. 

2 

 
 
 
 
Table of contents 

Summary ............................................................................................................................................................. 1 
Table of contents ............................................................................................................................................. 3 
Glossary ............................................................................................................................................................... 4 
Introduction .......................................................................................................................................... 7 
1. 
Background .............................................................................................................................................................................. 7 
1.1 
Choice of the material ....................................................................................................................................................... 8 
1.2 
Outline of the CRM project .............................................................................................................................................. 8 
1.3 
Participants ....................................................................................................................................... 10 
2. 
Project management, data evaluation and processing ............................................................................... 10 
2.1 
Homogeneity and stability measurements ......................................................................................................... 10 
2.2 
Characterisation measurements .............................................................................................................................. 10 
2.3 
Material processing and process control ............................................................................... 11 
3. 
Origin of the starting material ................................................................................................................................... 11 
3.1 
Processing.............................................................................................................................................................................. 11 
3.2 
Process control.................................................................................................................................................................... 12 
3.3 
Homogeneity ..................................................................................................................................... 13 
4. 
Between-unit homogeneity ......................................................................................................................................... 13 
4.1 
4.1.1  Homogeneity approach for chlormequat, glyphosate and AMPA ........................................................... 13 
4.1.2  Homogenity approach for the remaining pesticides...................................................................................... 13 
4.1.3  Results of the homogeneity tests ............................................................................................................................ 14 
Within-unit homogeneity and minimum sample size ................................................................................... 18 
4.2 
Stability .............................................................................................................................................. 19 
5. 
Short-term stability study ............................................................................................................................................ 19 
5.1 
Long-term stability study ............................................................................................................................................. 21 
5.2 
Estimation of uncertainties ......................................................................................................................................... 23 
5.3 
Characterisation .............................................................................................................................. 26 
6. 
Selection of participants................................................................................................................................................ 26 
6.1 
Study setup ........................................................................................................................................................................... 26 
6.2 
Methods used ...................................................................................................................................................................... 26 
6.3 
Dry mass determination ................................................................................................................................................ 27 
6.4 
6.5 
Evaluation of results ....................................................................................................................................................... 27 
6.5.1  Technical evaluation ........................................................................................................................................................ 27 
6.5.2  Statistical evaluation ....................................................................................................................................................... 27 
Value Assignment ........................................................................................................................... 31 
7. 
Certified values and their uncertainties ............................................................................................................... 31 
7.1 
Indicative values and their uncertainties ............................................................................................................. 33 
7.2 
Metrological traceability and commutability ....................................................................... 34 
8. 
Metrological traceability ................................................................................................................................................ 34 
8.1 
Commutability ..................................................................................................................................................................... 34 
8.2 
Instructions for use ........................................................................................................................ 35 
9. 
Safety information ........................................................................................................................................................... 35 
9.1 
Storage conditions ............................................................................................................................................................ 35 
9.2 
Preparation and use of the material ...................................................................................................................... 35 
9.3 
Minimum sample size ..................................................................................................................................................... 35 
9.4 
Dry mass correction ......................................................................................................................................................... 35 
9.5 
Use of the certified value ............................................................................................................................................. 35 
9.6 
Acknowledgements ......................................................................................................................... 37 
10. 
References ......................................................................................................................................... 38 
11. 

3 

 
Glossary 

AMPA 

ANOVA 

CAS 

CRM 

EC 

EI 

ERM® 

ESI 

EU 

GC 

GC-MS/MS 

GUM 

ISO 

JRC 

k 

Aminomethylphosphonic acid 

Analysis of variance 

Chemical Abstracts Service, Common Chemistry 

Certified reference material 

European Commission 

Electron ionisation 

Trademark owned by the European Commission; used by the JRC for 
reference materials 

Electrospray ionization 

European Union 

Gas chromatography 

Gas chromatography- triple quadrupole mass spectrometry 
Guide to the Expression of Uncertainty in Measurement 

International Organization for Standardization 

Joint Research Centre of the European Commission 

Coverage factor 

LC-MS/MS 

Liquid chromatography-triple quadrupole mass spectrometry 

LOD 

LOQ 

MRL 

MS 

MSbetween 

MSwithin 

n 

N 

n.a. 

n.c. 

p 

PSA 

QC 

QTOF 

QuEChERS 

rel 

RM 

Limit of detection 

Limit of quantification 

Maximum residue level 

Mass spectrometry 

Mean of squares between-unit from an ANOVA 

Mean of squares within-unit from an ANOVA 

Number of replicate analysis per unit 

Number of units analysed 

Not applicable 

Not calculated 

Number of technically valid datasets 

Primary and secondary amino exchange material 

Quality control 

Quadrupole time of flight 

Sample preparation approach; quick, easy, cheap, effective, rugged and safe 

Index denoting relative figures (uncertainties etc.) 

Reference material 

4 

 
s 

sbb 

sbetween 

SI 

swb 

swithin 

SPE 

Σ 

t 

ti 

t, df 

tsl 

ttt 

u 

U 

u*

bb 

ubb 

uchar 

uCRM 

UCRM 

uΔ 

ults 

umeas 

Umeas 

usts 

VIM 

Standard deviation 

Between-unit standard deviation; an additional index "rel" is added when 
appropriate; this parameter is linked to the homogeneity of the material 

Standard deviation between groups as obtained from ANOVA; an 
additional index "rel" is added as appropriate 

International System of Units 

Within-unit standard deviation; ; an additional index "rel" is added when 
appropriate; this parameter is linked to the homogeneity of the material 

Standard deviation within groups as obtained from ANOVA; an additional 
index "rel" is added as appropriate 

Solid phase extraction 

Sum of 

Time 

Time point for each replicate 

Critical t-value for a t-test, with a level of confidence of 1- and df 
degrees of freedom 

Proposed shelf life 

Proposed transport time 

Standard uncertainty 

Expanded uncertainty 

Standard uncertainty related to a maximum between-unit inhomogeneity 
that could be hidden by method repeatability, an additional index "rel" is 
added as appropriate 

Standard uncertainty related to a possible between-unit inhomogeneity; 
an additional index "rel" is added as appropriate 

Standard uncertainty of the material characterisation; an additional index 
"rel" is added as appropriate 

Combined standard uncertainty of the certified value; an additional index 
"rel" is added as appropriate 

Expanded uncertainty of the certified value; an additional index "rel" is 
added as appropriate 

Combined standard uncertainty of measurement result and certified 
value 

Standard uncertainty of the long-term stability; an additional index "rel" is 
added as appropriate 

Standard measurement uncertainty 

Expanded measurement uncertainty 

Standard uncertainty of the short-term stability; an additional index "rel" 
is added as appropriate 

International Vocabulary of Metrology – Basic and General Concepts and 
Associated Terms 

5 

 
 

meas 

MSwithin 

X10 

X50 

X90 

y(cid:3364) 

Significance level 

Absolute difference between mean measured value and the certified 
value 

Degrees of freedom of MSwithin 

Particle diameter corresponding to 10 % of the cumulative undersize 
distribution (here by volume) 

Median particle diameter corresponding to 50 % of the cumulative 
undersize distribution (here by volume) 

Particle diameter corresponding to 90 % of the cumulative undersize 
distribution (here by volume) 

Mean of all results of the homogeneity study 

6 

 
 
 
 
1. Introduction 

1.1  Background 

To ensure safe food for the citizens, European legislation establishes maximum residue levels (MRL) 
of  pesticide  residues  in  food  stuffs  [4].  Compliance  with  these  levels  is  required  prior  to 
commercialization of products inside the EU. To perform the control and monitoring, laboratories need 
reliable  analytical  methods  which  are  developed  and  validated  in  accordance  with  the  quality 
standard  requirements  listed  in  ISO/IEC  17025  [3].  Usually,  multi-residual  analytical  methods  are 
developed as a way to optimise the process. Yet the list of active compounds and their metabolites 
which  are  authorised  or  banned  for  use  in  the  EU  is  extensive.  Therefore,  the  validation  of  the 
analytical methods has become a complex and highly time consuming task. The effort required is 
significantly increased when considering the large amount of different food commodities, giving rise 
to thousands of matrix/pesticide combinations. 

Being aware of this challenge, the European Commission's Directorate for Health and Food Safety 
(DG SANTE) has developed guidance on the validation of analytical procedures for pesticides which 
is  regularly  updated  [5,  6].  The  guidance  document  groups  certain  commodities  in  categories.  For 
vegetables and fruits, cereals and food of animal origin, ten commodity clusters are distinguished 
based on composition:  

-  high water content  
-  high acid content and high water content  
-  high sugar and low water content  
-  high oil content and low/intermediate water content 
-  high starch and/or protein content with low water and fat content 
-  difficult or unique commodities 
-  meat and seafood 
-  milk and milk products 
- 
- 

eggs 
fat from food of animal origin 

Each category can be represented by one typical commodity that would be employed during method 
validation resulting in a significant simplification for the laboratories. Still, all active compounds and 
metabolites within the scope of the analytical method need validation, including the assessment of 
accuracy.  

According to ISO/IEC 17025, the use of reference materials and the participation in proficiency testing 
schemes are essential tools for assuring and controlling the quality of analytical data [3]. Likewise, 
the validation guidance document specifies Certified Reference Materials (CRMs) as the preferable 
option to provide evidence of analytical method performance [5]. CRMs are used for verification of 
the  accuracy  and  trueness,  for  the  estimation  of  measurement  uncertainty  and  to  establish  the 
metrological traceability of analytical results. For pesticide analysis, access to matrix CRMs is currently 
limited. 

To cover this need and to contribute to the harmonisation of reliable analytical results, and the proper 
implementation  of  EU  legislation,  the  Joint  Research  Centre  of  the  European  Commission  has 
produced  a  suite  of  CRMs  covering  pesticides  in  food  commodities  of  high  water  content  (ERM-
BC403), high oil content (ERM-BC700) and eggs (ERM-BB125). The present CRM (ERM-BC706) has 
been planned in collaboration with the European Union Reference Laboratory for Cereals (EURL-CF) 
in order to select a representative combination of pesticides in a high starch plant species with low 
water and fat content commodity. 

Wheat (Kalmar) was chosen as a characteristic matrix for this group. For the production of this wheat-
based  CRM, a range  of pesticides (see  Annex A) were  carefully selected based on their  use  in  the 
commodity, their authorisation status in the EU legislation and their different chemical properties.  

7 

 
1.2  Choice of the material 

Wheat flour was selected as a matrix to represent groups of food commodities with high starch and 
low water and fat content [5]. Wheat grains originating from Denmark were provided by the Aarhus 
University Science and Technology, Department of Agroecology, Slagelse, DK. 

Target pesticides were carefully chosen based on a number of criteria with the intention to achieve a 
broad coverage of different aspects such as the chemical compound families, their intended use, the 
simplicity/difficulty of analysis as well as to include pesticides which are authorised or banned for 
use in the EU. Annex A includes information about the different compounds.  

The target mass fraction levels for pesticides in the wheat flour material were mainly chosen based 
on the range of the MRLs established for the different residues by the EU legislation [4]. For some 
pesticides, the target mass fractions in the matrix were set to cover values near the MRLs and for 
other pesticides  higher levels were chosen to allow for testing of entire calibration ranges..  

Where the EU legislation [4] stipulates an MRL based on the sum of pesticides, these are included in 
the calculations (see Annex A for details). It should be noted that the certified values for the sum 
contain only datasets where all individual components  of the  sum are provided  by the  participant 
laboratories.  There  are  a  few  other  particular  cases  to  be  noted.  For  deltamethrin,  the  MRL  is 
established for cis-deltamethrin. This compound separates chromatographically in two peaks and the 
distribution  can  vary  due  to  the  high  possibility  of  isomerisation  (between  different  cis-isomers) 
happening during the sample treatment, when using primary and secondary amino exchange material 
(PSA) in the clean-up, or in the GC-system [7,8]. The mass fraction of cis-deltamethrin is therefore 
reported as the sum of cis-isomers eluting in the two peaks. Chlormequat is reported as the sum of 
chlormequat and its salts, and imazalil is reported as the ratio of constituent isomers. Cypermethrin 
and permethrin are both reported as the sum of isomers in accordance with the EU legislation.  

1.3  Outline of the CRM project 

The production of a CRM as defined in ISO 17034 [1] is a project comprising planning, processing of 
the material, homogeneity and stability testing, characterisation and assigning of the property values 
and  finally  distribution  and  post-certification  monitoring  to  control  stability.  Selected  laboratories 
taking part in the production are ISO/IEC 17025 accredited for the particular applications. 

The  wheat  was  treated  on  the  field  with  the  following  pesticides:  azoxystrobin,  chlormequat, 
cypermethrin, deltamethrin, fipronil, glyphosate, imidacloprid, malathion and tebuconazole. Not all the 
target pesticides were possible to spray on the field, mainly due to their characteristics; chlorpyrifos, 
diazinon, dichlorvos, endosulfan, endosulfan sulfate, linuron and permethrin are not approved for use 
on the test field, and imazalil and thiabendazole are used as seed treatment before sowing and not 
applied on the plant. Furthermore some of the pesticides sprayed in the field (namely cypermethrin, 
deltamethrin, fipronil, fipronil sulfone and malathion), were not detected in the processed wheat flour 
at  quantifiable  levels.  It  was  therefore  necessary  to  treat  the  wheat,  once  harvested,  with  these 
pesticides a second time together with the pesticides not sprayed on the field. The harvested, treated 
grains were therefore sprayed with the following pesticides: chlorpyrifos, cypermethrin, deltamethrin, 
diazinon,  dichlorvos,  endosulfan,  endosulfan  sulfate,  fipronil,  fipronil  sulfone,  imazalil,  linuron, 
malathion,  permethrin  and 
(malaoxon  and 
aminomethylphoshonic  acid  (AMPA))  were  analysed  because  of  potential  degradation  of  the 
pesticides malathion and glyphosate respectively. 

thiabendazole.  Two  additional  pesticides 

Homogeneity and stability testing was done by validated and  accredited analytical  methodologies 
based on GC- and LC-MS/MS. 

Characterisation is based on an inter-laboratory comparison involving a number of expert laboratories 
in the field of pesticide residue analysis. The participants in the characterisation phase were requested 
to apply their own validated analytical methodology for the determination of pesticides in wheat and 
report values based on dry mass and corrected for recovery. Together with the candidate CRM ERM-

8 

 
BC706, the laboratories received an additional method quality control sample (MQC) of blank wheat 
flour material. The laboratories were instructed to report the blank values found. Furthermore, the 
MQC sample could be used for the laboratory's quality control and/or to be used for matrix matched 
calibration purposes.  

Uncertainties of certified and indicative values were estimated in compliance  with ISO  17034  [1], 
which implements the basic principles of ISO/IEC Guide 98 (GUM) [9].  

The CRM project, including the certification approach and the evaluation of the obtained measurement 
data, was subjected to peer-review involving both internal and external experts. 

9 

 
2. Participants 

2.1 

Project management, data evaluation and processing 

European  Commission,  Joint  Research  Centre,  Directorate  F  –  Health,  Consumers  and  Reference 
Materials, Unit F.6 (Reference Materials Unit), Geel, BE 
(accredited to ISO 17034:2016 for production of certified reference materials, BELAC No. 268-RM) 

2.2  Homogeneity and stability measurements 

European  Commission,  Joint  Research  Centre,  Directorate  F  –  Health,  Consumers  and  Reference 
Materials, Geel, BE 
(measurements under the scope of ISO/IEC 17025:2017 accreditation by BELAC, accreditation No. 268-TEST)  

WFSR Wageningen Food Safety Research, Wageningen, NL  
(measurements under the scope of ISO/IEC 17025 accreditation by RvA, accreditation No. L235) 

2.3  Characterisation measurements 

AGQ Labs & Technological Services, Sevilla, ES  
(measurements under the scope of ISO/IEC 17025:2017 accreditation by ENAC; accreditation number 305/LE1323) 

BIOR, Institute of Food Safety, Animal Health and Environment, Riga, LV  
(measurements under the scope of ISO/IEC 17025:2017 accreditation by LATAK, accreditation number T-012-39-95) 

DTU Fødevareinstituttet, Danmarks Tekniske Universitet, Kgs. Lyngby, DK 
(measurements under the scope of ISO/IEC 17025:2017 accreditation by DANAK, accreditation 350) 

European  Commission,  Joint  Research  Centre,  Directorate  F  –  Health,  Consumers  and  Reference 
Materials, Geel, BE 
(measurements under the scope of ISO/IEC 17025:2017 accreditation by BELAC, accreditation number 268-TEST) 

Finnish Customs Laboratory, Helsinki, FI 
(measurements under the scope of ISO/IEC 17025:2017 accreditation by FINAS, accreditation number T006) 

Institut Dr. Wagner Lebensmittel Analytik GmbH, Lebring, AT  
(measurements under the scope of ISO/IEC 17025:2017 accreditation by Akkreditierung Österreich, accreditation number 
0239) 

Istituto Zooprofilattico Sperimentale dell'Umbria e delle Marche, Perugia, IT  
(measurements under the scope of ISO/IEC 17025:2017 accreditation by Accredia, accreditation number 0217) 

LUFA-Speyer, Landwirtschaftliche Untersuchungs- und Forschungsanstalt Speyer, Speyer, DE 
(measurements under the scope of ISO/IEC 17025:2017 accreditation by DAkkS, accreditation number D-PL-14609-01-
00) 

Reactiva Laboratorio S.L., Almería, ES 
(measurements under the scope of ISO/IEC 17025:2017 accreditation by ENAC; accreditation number 543/LE1458) 

Sciensano, Brussel, BE 
(measurements under the scope of ISO/IEC 17025:2017 accreditation by BELAC, accreditation number 081-TEST) 

All  laboratories  are identified  by  a code (e.g.  L01).  The  numbering is  not  in  the  alphabetical  order 
presented above. 

10 

 
 
 
 
 
 
 
 
 
 
 
3. Material processing and process control 

3.1  Origin of the starting material 

Wheat (Kalmar)  was  provided  by  Department  of Agroecology,  Aarhus  University,  DK.  The material 
consisted  of  wheat  kernels  which  were  exposed  to  9  pesticides  (azoxystrobin,  chlormequat, 
cypermethrin,  deltamethrin,  fipronil,  glyphosate,  imidacloprid,  malathion  and  tebuconazole)  in  the 
field  of  the  research  station  during  July  2019  and harvested  in August  2019.  Additionally,  wheat 
without any treatment was grown at the same time. This untreated material was intended for a blank 
material used as MQC sample during characterisation. The exposed material was screened for the 
target pesticides. From these, azoxystrobin, chlormequat, glyphosate, imidacloprid and tebuconazole 
were found in quantifiable levels while the remaining pesticides were not detectable (below LOQ 0.01 
mg/kg). 

3.2 

Processing 

The  material  was  distributed  in  trays  and  the  wheat  was  sprayed  in  the  trays  with  a  solution  of 
fourteen  pesticides;  chlorpyrifos,  cypermethrin,  deltamehtrin,  diazinon,  dichlorvos,  endosulfan, 
endosulfan  sulfate,  fipronil,  fipronil  sulfone,  imazalil,  linuron,  permethrin  and  thiabendazole.    (see 
annex A for details) The pesticide solution was prepared from pure substances in a water/methanol 
solution. The trays were then placed into a rack and let to dry overnight in a ventilated but closed 
environment.  

The  wheat  kernels  sprayed  with  pesticides  were cooled  with liquid nitrogen at -196  °C  and milled 
using  a  Palla  VM-KT  vibrating  cryogenic  mill  (KHD  Humboldt  Wedag,  Cologne,  DE).  After  sieving 
through a 500 µm sieve using a Russel fine industrial sieve (Russell Finex London, UK), the coarse 
fraction larger than 500 µm was re-milled and added to the rest of the bulk material. The wheat 
powder was mixed using a Dyna-Mix CM200 three-dimensional mixer (Dyna-Mix CM200, Basel, CH) 
for one hour and kept in stainless steel drums at -20 °C until filling. The wheat blank material (MQC 
sample) was processed in the same way, apart from the spraying and air drying step. 

An MCPI vibrating filling machine (Meythet Cedex, France) was used to fill 45 g of powder into 125 
ml amber powder bottles under a nitrogen atmosphere. The bottles were closed with a PTFE coated 
screw cap and break ring. After labelling, the bottles were individually placed and sealed into pre-
labelled laminated aluminium pouches to protect the material from light and oxygen and thereafter 
stored at -40 °C.  

For the purpose of this report, the term ‘unit’ refers to one bottle of ERM-BC706, containing 45 g of 
powder. An example of ERM-BC706 is shown in Figure 1.  

Figure 1: ERM BC706 

11 

 
 
3.3 

Process control  

Water  content  in  the  fully  processed  wheat  powder  was  measured  in  duplicate  for  five  samples 
covering  the  filling  sequence  using  Volumetric-Karl  Fischer  titration  (Metrohm,  Herisau,  CH).  The 
average result was 12.63 ± 0.27 % (m/m) (expanded uncertainty (U, k=2)). 

Particle  size  distribution  measurements  based  on  laser  diffraction  (Helos  KR,  Sympatec  GmbH, 
Clausthal-Zellerfeld, DE) took place after the final processing of ERM-BC706. The particle size analysis 
was performed in duplicate on five units of the final material. Volume-weighted mean particle size 
of cumulative (Q3) and density (q3*) distributions for the final product are depicted in Figure 2.  

Results for the particle size distribution showed an average standard deviation for the X10, X50 and X90 
size classes (on the cumulative particle size distribution curve) well below 20 % (Table 1). 

1.0

%

/

3
Q
n
o

i
t

u
b
i
r
t
s
d
e
v
i
t

i

l

a
u
m
u
C

100
90

80
70

60

50

40
30

20

10
0
0.5

*
3
q
n
o

i
t

u
b
i
r
t
s
d
y
t
i

i

s
n
e
D

0.9

0.8

0.7

0.6
0.5

0.4

0.3

0.2

0.1
0.0

1.0

5

10

50

100

500 1000

particle size / µm

Figure 2: Mean particle size distribution for ERM-BC706 for N = 5, n = 2. Standard deviations are 
given in Table 1. 

Table 1: Results from the particle size analysis   

Upper band limit 

Mean particle size  
[µm] (N = 5, n = 2) 

Standard deviation 
[µm] 

Relative standard 
deviation  [%] 

X10 

X50 

X90 

17.48 

103.02 

305.47 

1.48 

11.52 

32.06 

8.5 

11.2 

10.5 

12 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4. Homogeneity 

A key requirement for any reference material produced as a batch of units is equivalence between 
those units. In this respect, it is relevant whether the variation between units is significant compared 
to  the  uncertainty  of  the  certified  value,  but  it  is  not  relevant  if  this  variation  between  units  is 
significant compared to the variation of measurement results. Consequently, ISO 17034 [1] requires 
RM  producers  to  quantify  the  between-unit  variation.  This  aspect  is  covered  in  between-unit 
homogeneity studies. 

The  within-unit  inhomogeneity  does  not  influence  the  uncertainty  of  the  certified  value  when the 
minimum sample size is respected, but determines the minimum size of sample that is representative 
for the whole unit. Quantification of within-unit homogeneity is therefore necessary to determine the 
minimum sample size. 

4.1  Between-unit homogeneity 

The between-unit homogeneity is evaluated to ensure that the certified values of the CRM are valid 
for all units of the material, within the stated uncertainties. 

The number of units selected corresponds to approximately the cube root of the total number of units 
produced. Thirteen units were selected using a random stratified sampling scheme covering the whole 
batch for the between-unit homogeneity test. Random stratified sampling involves dividing the batch 
into 13 groups (with a similar number of units in each group) and selecting one unit randomly from 
each group. Three independent samples were taken from each of the 13 selected units, and analysed 
by GC-MS/MS and LC-MS/MS.  

4.1.1 
Homogeneity approach for chlormequat, glyphosate and AMPA 
The  measurements  for  the  pesticides  chlormequat,  glyphosate  and  AMPA  were  performed  under 
repeatability  conditions  (in  one  analytical  sequence),  and  in  a  randomised  manner  to  separate  a 
potential drift in the measurement results from a potential trend in the filling sequence.   The obtained 
results are presented in annex B. 

The dataset was assessed for consistency using Grubbs outlier tests at a confidence level of 99 % on 
the individual results and on the unit means 

Quantification  of  between-unit  inhomogeneity  was  undertaken  by  analysis  of  variance  (ANOVA), 
which  separates  the  between-unit  variation  (sbb)  from  the  within-unit  variation  (swb).  The  latter  is 
equivalent to the method repeatability. 

Evaluation by ANOVA requires mean values per unit, which follow at least a unimodal distribution and 
results  for  each  unit  that  follow  unimodal  distributions  with  approximately  the  same  standard 
deviations.  The distribution of the mean values per unit was visually tested using histograms  and 
normal probability plots. Too few data are available for the unit means to make a clear statement of 
the  distribution.  Therefore,  it  was  checked  visually  whether  all  individual  data  follow  a  unimodal 
distribution using histograms and normal probability plots. Minor deviations from unimodality of the 
individual values do not significantly affect the estimate of between-unit standard deviations. The 
results of all statistical evaluations are given in Table 2. 

. 

Homogenity approach for the remaining pesticides 

4.1.2 
The  measurements  for  the  remaining  pesticides  were  performed  under  intermediate  precision 
conditions (on five different days). Consequently, day-to-day effects could occur for these pesticides 
that could mask the between-unit variation. To rule out or compensate for that possibility, significant 

13 

 
differences between the day means for the remaining pesticides were tested by analysis of variance 
(ANOVA) at a 95 % confidence level.  

Significant day-to-day effects  were  found  for  azoxystrobin, chlorpyrifos,  diazinon,  fipronil  sulfone, 
linuron, malaoxon, malathion and tebuconazole. Therefore the data were first normalised for all the 
pesticides measured under intermediate precision conditions to the respective day means and tested 
for outlying sample means and trends in the filling sequence. The obtained results are presented in 
annex B. 

One  outlier  on  the  individual  results  was  detected  for  deltamethrin  and  imidacloprid  at  99% 
confidence level. Since no technical reason for the outliers could be found, the data were retained for 
statistical  analysis.  No  outliers  and  trends  neither  in  the  filling  nor  the  analytical  sequence  were 
detected for the remaining pesticides.  

Subsequently,  between-unit  homogeneity  was  assessed  by  two-way  ANOVA  on  the  original,  non-
normalised  data  using  Statistika  13.5017  (Dell  Software,  Round  Rock,  USA).  Two-way  ANOVA 
differentiates  between  sample-to-sample,  day-to-day,  and  random  effects.  The  between-unit 
variation  (sbb)  is  separated  from  the  within-unit  variation  (swb),  which  is  equivalent  to  the  method 
intermediate precision.  

Tests for normality/unimodality were  performed as described in section 4.1.1. 

4.1.3 
The results of all statistical evaluations are given in Table 2.  

Results of the homogeneity tests 

14 

 
 
 
 
Table 2: Results of the statistical evaluation of the homogeneity studies  

Trends 1) 

Outliers 2) 

Distribution 

Pesticide 

Measure
ment 
sequence 

Filling 
sequence 

Individual 
results 

Unit 
means 

Individual 
results 

Unit 
means 

AMPA 

Azoxystrobin 

Chlormequat 

Chlorpyrifos 

Cypermethrin 

Deltamethrin 

Diazinon 

Dichlorvos 

α-Endosulfan 

β-Endosulfan 

Endosulfan sulfate 

Sum of α- and β-
endosulfan and 
endosulfan sulfate 
expressed as endosulfan 

Fipronil 

Fipronil sulfone 

Sum of fipronil and 
fipronil sulfone expressed 
as fipronil 

Glyphosate 

Imazalil 

Imidacloprid 

Linuron 

Malaoxon 

Malathion 

Sum of malathion and 
malaoxon expressed as 
malathion 

Permethrin 

Tebuconazole 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

normal 

unimodal 

normal 

unimodal 

normal 

unimodal 

normal 

normal 

normal 

normal 

1 -retained 

none 

normal 

normal 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

normal 

normal 

unimodal 

unimodal 

normal 

unimodal 

normal 

unimodal 

normal 

normal 

none 

none 

normal 

normal 

none 

none 

none 

none 

normal 

unimodal 

normal 

normal 

none 

none 

normal 

normal 

none 

none 

none 

none 

normal 

unimodal 

normal 

normal 

1 -retained 

none 

normal 

normal 

none 

none 

none 

none 

none 

none 

normal 

normal 

normal 

unimodal 

normal 

normal 

none 

none 

normal 

normal 

none 

none 

none 

none 

normal 

unimodal 

unimodal 

unimodal 

Thiabendazole 

unimodal 
no 
1) 95 % confidence level, performed on normalised values apart from chlormequat, glyphosate and AMPA 
2) 99 % confidence level 

none 

none 

no 

unimodal 

15 

 
 
It should be noted that sbb, rel and swb, rel are estimates of the standard deviations and are therefore 
consequently subject to random fluctuations. Therefore, the mean square between groups (MSbetween) 
can be smaller than the mean squares within groups (MSwithin), resulting in a negative number under 
the square root used for the estimation of the  between-unit variation, whereas the true  variation 
cannot  be  less  than  zero.  In  this  case,  u*
bb,  the  maximum  inhomogeneity  that  could  be  hidden  by 
method repeatability, was calculated as described by Linsinger et al. [10]. u*
bb is comparable to the 
limit of detection (LOD) of a measurement method yielding the maximum degree of inhomogeneity 
that might be undetected by the given study setup. 

Method repeatability (swb,  rel) (equivalent to the within-unit standard deviation for 1-way ANOVA or 
intermediate precision in case of 2-way ANOVA), between–unit standard deviation (sbb, rel) and u*
bb, rel 
were calculated as:  

swb, rel = 

(cid:3493)MSwithin
y(cid:3364)

sbb, rel = 

(cid:3495)MSbetween - MSwithin
n
y(cid:3364)

*
ubb, rel

 = 

(cid:3495)MSwithin
n

4
(cid:3495)

2
MSwithin

y(cid:3364)

Equation 1 

Equation 2 

Equation 3 

MSwithin 
MSbetween 
y(cid:3364) 
n 
MSwithin 

mean of squares within-unit from ANOVA  
mean of squares between-unit from ANOVA 
mean of all results of the homogeneity study 
mean number of replicate analysis per unit 
degrees of freedom of MSwithin 

The results of the evaluation of the between-unit variation are summarised in Table 3. The resulting 
values  from  the  above  equations  were  converted  into  relative  uncertainties.  In  most  cases,  the 
uncertainty contribution for homogeneity was determined by the method repeatability or intermediate 
precision. 

16 

 
 
 
 
 
 
 
   
 
 
 
 
   
 
 
 
 
 
 
 
 
Table 3: Results of the homogeneity studies 

Pesticide 

AMPA 

Azoxystrobin 

Chlormequat 

Chlorpyrifos 

Cypermethrin 

Deltamethrin 

Diazinon 

Dichlorvos 

α-Endosulfan 

β-Endosulfan 

Endosulfan sulfate 

Sum of α- and β-endosulfan and endosulfan 
sulfate expressed as endosulfan 

Fipronil 

Fipronil sulfone 

Sum of fipronil and fipronil sulfone expressed 
as fipronil 

Glyphosate 

Imazalil 

Imidacloprid 

Linuron 

Malaoxon 

Malathion 

Sum of malathion and malaoxon expressed as 
malathion 

Permethrin 

Tebuconazole 

Thiabendazole 
1) n.c.: cannot be calculated as MSbetween < MSwithin 

swb, rel 

[%] 

6.59 

2.93 

2.39 

1.95 

1.78 

2.96 

1.30 

5.48 

4.10 

5.53 

2.10 

2.31 

2.83 

1.02 

1.43 

5.98 

3.67 

4.42 

2.74 

4.24 

1.57 

1.57 

1.46 

4.06 

1.90 

sbb, rel 

[%] 

3.93 

0.79 

n.c. 

0.79 

n.c 

1.24 

0.42 

1.90 

1.38 

n.c 

0.96 

n.c 

n.c 

n.c 

n.c 

n.c. 

0.86 

n.c 

n.c 

n.c 

1.08 

u*

bb, rel 

[%] 

1.97 

1.25 

0.71 

0.83 

0.76 

1.26 

0.55 

2.33 

1.75 

2.35 

0.89 

0.98 

1.21 

0.43 

0.61 

1.79 

1.56 

1.88 

1.17 

1.80 

0.67 

ubb, rel 

[%] 

3.93 

1.25 

0.71 

0.83 

0.76 

1.26 

0.55 

2.33 

1.75 

2.35 

0.96 

0.98 

1.21 

0.43 

0.61 

1.79 

1.56 

1.88 

1.17 

1.80 

1.08 

1.08 

0.67 

1.08 

0.13 

1.46 

n.c 

0.62 

1.73 

0.81 

0.62 

1.73 

0.81 

The homogeneity studies showed no outlying unit means or trends in the filling sequence. Therefore, 
the between-unit standard deviation can be used as an estimate of ubb. As u*
bb sets the limits of the 
study to detect inhomogeneity, the larger value of sbb and u*
bb is adopted as uncertainty contribution 
to account for potential inhomogeneity. 

17 

 
 
4.2  Within-unit homogeneity and minimum sample size 

The within-unit homogeneity is correlated to the minimum sample size. As a result, individual samples 
of a unit will not contain the same amount of analyte if the sample intake is too small. The minimum 
sample size is the minimum amount of sample that is, for a given measurand, representative of the 
whole  unit  and  thus  should  be  used  in  an  analysis.  Using  sample  intakes  equal  to  or  above  the 
minimum sample size guarantees the certified value within its stated uncertainty. 

Homogeneity experiments were performed using a 1 g sample intake for the pesticides mentioned in 
section  4.1.2.  This  sample  intake  gives  acceptable  intermediate  precision,  demonstrating  that  the 
within-unit inhomogeneity no longer contributes to variation of measurement results. 

The  minimum  sample  size  for  AMPA,  chlormequat  and  glyphosate  was  established  based  on  the 
technically valid results of the characterisation study, using the method information supplied by the 
participants.  The  smallest  sample  intake  that  still  yielded  results  with  acceptable  precision  to  be 
included in the respective studies was taken as minimum sample size. Using the data from Annex E, 
the minimum  sample  size  is  1 g.  The  overall  minimum  sample  size  for  this material,  valid  for  all 
pesticides investigated, is set to 1 g. 

18 

 
 
 
5. Stability 

Time, temperature, light (including ultraviolet radiation) and water content were regarded as the most 
relevant influences on the stability of the materials. The influence of ultraviolet and visible light was 
minimised by storing the material in containers, which reduce light exposure. In addition, materials 
were stored in the dark and dispatched in boxes, thus removing any possibility of degradation by light. 
As  the  water  content  was  controlled  during  processing  and  remained  close  to  the  natural  water 
content in wheat, only the influences of time and temperature needed to be investigated. 

Stability testing is necessary to establish the conditions for storage (long-term stability) as well as 
the conditions for dispatch of the materials to the customers (short-term stability). During transport, 
especially in summer, temperatures up to 60 °C can be reached, and stability under these conditions 
must be demonstrated in case samples are to be transported without any additional cooling. 

The stability studies were carried out using an isochronous design [11]. In this approach, units were 
stored for a particular period of time in different temperature conditions. Afterwards, the units were 
moved to conditions where further degradation can be assumed negligible (reference conditions). At 
the end of the isochronous storage, the samples were analysed simultaneously under repeatability 
conditions.  Analysis  of  the  material  (after  various  exposure  times  and  temperatures)  under 
repeatability conditions greatly improves the sensitivity of the stability tests. 

5.1  Short-term stability study 

In the short-term stability study, the conditions for dispatch of the material to the customers were 
established. To this end, units were stored at 4 °C and 18 °C for 0, 1, 2 and 4 weeks respectively. The 
reference temperature was set to -70 °C. Two units per temperature and storage time were selected 
using a random stratified sampling scheme. From each unit, three samples were measured by GC-
MS/MS  or  LC-MS/MS.  Measurements  were  performed  under  repeatability  conditions,  and  in  a 
randomised sequence in order to differentiate any potential drift in the measurement results from a 
potential trend over storage time.  

The  data were  evaluated individually  for each temperature and results were screened for  outliers 
using the single and double Grubbs test on a confidence level of 99 %. 

In  addition,  the  data  were  evaluated  against  storage  time,  and  regression  lines  of  mass  fraction 
versus time were calculated, to test for potential increases or decreases of the pesticide mass fraction 
due to shipping conditions. The slopes of the regression lines were tested for statistical significance. 

The results of the measurements are shown in Annex C. The results of the statistical evaluation of 
the short-term stability are summarised in Table 4.  

19 

 
 
 
 
Table 4: Results of the short-term stability tests 

Pesticide 

AMPA 

Azoxystrobin 

Chlormequat 

Chlorpyrifos 

Cypermethrin 

Deltamethrin 

Diazinon 

Dichlorvos 

α-Endosulfan 

β-Endosulfan 

Endosulfan sulfate 

Sum of α- and β-endosulfan 
and endosulfan sulfate 
expressed as endosulfan 

Fipronil 

Fipronil sulfone 

Sum of fipronil and fipronil 
sulfone expressed as fipronil 

Glyphosate 

Imazalil 

Imidacloprid 

Linuron 

Malaoxon 

Malathion 

Sum of malathion and 
malaoxon expressed as 
malathion 

Permethrin 

Tebuconazole 

Thiabendazole 

1) 99 % confidence level 
2) 95 % confidence level 

Number of individual outlying 
results 1) 

statistical (retained) 
18 °C 

4 °C 

none 

none 

none 

none 

none 

none 

1 -retained 

2 - retained 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

1 -retained 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

1 -retained 

none 

none 

none 

none 

none 

none 

none 

20 

Significance of the trend 2) 

4 °C 

no 

yes 

no 

no 

no 

no 

no 

yes 

no 

no 

no 

no 

yes  

no 

yes 

no 

no 

no 

no 

yes 

no 

no 

no 

no 

no 

18 °C 

yes 

yes 

no 

no 

no 

no 

yes 

yes 

no 

no 

no 

no 

yes 

yes 

no 

no 

no 

no 

yes 

yes 

no 

no 

no 

yes 

no 

 
 
One individual statistical outlier was detected for chlorpyrifos, deltamethrin and imidacloprid at 4 °C. 
and two for chlorpyrifos at 18 °C. As no technical reason for these outliers could be found all data 
were retained for the estimation of usts.  

A significant trend at 4 °C was found for azoxystrobin, dichlorvos, fipronil and malaoxon.  

A positive trend at 4 °C was observed for fipronil, sum of fipronil, and malaoxon. As fipronil can only 
degrade in the sample, it cannot be formed. Therefore a positive trend can only be due to degradation 
of the matrix. This, however, should be seen for all measurands, which is not the case. The observed 
trend was therefore regarded as a statistical artefact. Malaoxon which is a degradation product of 
malathion,  showed  a  significant  trend  indicating  degradation  of  malathion.  Since  the  content  of 
malaoxon  in  comparison  to  malathion  is  negligible  (<  0.2  %),  this  degradation  is  hidden  in  the 
measurement uncertainty of malathion. Based on this study, the material shows clear indication of 
temperature sensitivity even for a short period of time. 

Based on the study, the material shall be shipped frozen. 

5.2 

Long-term stability study 

Long-term storage conditions and shelf life guaranteeing the stability of the material and the certified 
values were established. 

To  this  end,  units  were  stored  at  -20 °C  and  -40 °C  for  0,  4,  8  and  12  months,  respectively.  The 
reference temperature was set to -70 °C. Two units per storage time were selected using a random 
stratified sampling scheme. From each unit, three samples were analysed by GC-MS/MS and/or LC-
MS/MS. The measurements were performed under repeatability conditions and in a random sequence 
to be able to  separate any  potential drift in the measurement results from  a potential trend over 
storage time.  

Long-term stability data were evaluated individually for each temperature. The results were screened 
for outliers using the single and double Grubbs test at a confidence level of 99 %. 

In addition, data were plotted against storage time and linear regression lines of mass fraction versus 
time  were  calculated.  The  slopes  of  the  regression  lines  were  tested  for  statistical  significance 
(loss/increase due to storage). 

The  results  of  the  long-term  stability  measurements  are  shown  in  Annex  D.  The  results  of  the 
statistical evaluation of the long-term stability study are summarised in Table 5.  

21 

 
 
 
 
Table 5: Results of the long-term stability tests 

Pesticide 

Number of individual outlying 
results 1) 

statistical (retained) 

Significance of the trend 2) 

-20 °C 

-40 °C 

-20 °C 

-40 °C 

none 

none 

none 

none 

none 

none 

none 

none 

1 -retained 

none 

none 

none 

none 

none 

none 

none 

none 

n.d.3) 

none 

none 

none 

none 

none 

none 

none 

no 

no 

no 

no 

no 

no 

no 

yes 

no 

no 

no 

no 

no 

no 

no 

yes 

no 

no 

no 

yes 

no 

no 

yes 

no 

no 

AMPA 

Azoxystrobin 

Chlormequat 

Chlorpyrifos 

Cypermethrin 

Deltamethrin 

Diazinon 

Dichlorvos 

α-Endosulfan 

β-Endosulfan 

Endosulfan sulfate 

Sum of α- and β-endosulfan 
and endosulfan sulfate 
expressed as endosulfan 

Fipronil 

Fipronil sulfone 

Sum of fipronil and fipronil 
sulfone expressed as fipronil 

Glyphosate 

Imazalil 

Imidacloprid 

Linuron 

Malaoxon 

Malathion 

Sum of malathion and 
malaoxon expressed as 
malathion 

Permethrin 

Tebuconazole 

Thiabendazole 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

none 

1) 99 % confidence level 
2) 95 % confidence level 
3) n.d. not sufficient data points / technical reason  

22 

no 

no 

yes 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

no 

n.d.3) 

no 

no 

no 

no 

no 

no 

no 

 
 
During  the  analysis  fipronil  sulfone,  imidacloprid  and  malaoxon  showed  a  statistical  bias  for  the 
quality control sample. As the objective of this study is to detect temperature effects, the repeatable 
analytical conditions are of prime importance, whereas trueness does not play a role. The values for 
these three pesticides are therefore reported as normalised values. The normalisation is done versus 
the average result obtained for the reference samples (t=0). 

One statistical outlier was detected for α-endosulfan at -40 °C. As no technical reason for this outlier 
could be found, all data were retained for the estimation of ults.  

A technical problem occurred during the analysis of imidacloprid. Since there were insufficient data 
points to evaluate the trend, the ults for this pesticide is estimated on the higher temperature -20 °C, 
as a conservative estimate. 

A  positive  trend  was  observed  for  chlormequat  at  -40 °C  and  for  glyphosate  at  -20  °C.  As  these 
measurands cannot be created in the sample, a positive trend could only be due to degradation of 
the matrix. This, however, should be seen for all measurands, which is not the case. The observed 
trends were therefore regarded as a statistical artefacts. 

Dichlorvos, malaoxon and permethrin showed negative trends which were statistically significant on 
a 95 % confidence level at -20 °C however these trends were not visible at -40 °C. The material will 
therefore be stored at -40 °C. 

5.3 

Estimation of uncertainties 

Due to the intrinsic variation of measurement results, no study can entirely rule out degradation of 
materials, even in the absence of statistically significant trends. It is therefore necessary to quantify 
the  potential  degradation  that  could  be  hidden  by  the  method  repeatability,  i.e.  to  estimate  the 
uncertainty of stability. This means that, even under ideal conditions, the outcome of a stability study 
can only be that there is no detectable degradation within an uncertainty to be estimated. 

The uncertainties of stability during dispatch and storage were estimated, as described in [12] for 
each pesticide. In this approach, the uncertainty of the linear regression line with a slope of zero was 
calculated. The uncertainty contributions usts and ults were calculated as the product of the chosen 
transport time/shelf life and the uncertainty of the regression lines as: 

usts, rel = 

srel

(cid:3495)∑ (ti - t(cid:3365))

2

 ∙ ttt 

ults, rel = 

srel

(cid:3495)∑ (ti - t̅)

2

 ∙ tsl 

Equation 4 

Equation 5 

srel 
ti 
t̅ 
ttt 
tsl 

relative standard deviation of all results of the stability study 
time elapsed at time point i 
mean of all ti 
chosen transport time (1 month at -20 °C) 
chosen shelf life (12 months at -40 °C) 

As the material showed degradation for the temperatures tested during the short-term stability study, 
a lower temperature was selected for dispatch of the samples and the uncertainty of stability during 
dispatch could not be estimated, as described in [ ]. Instead, the uncertainty contribution of the long-
term stability study is used to assess usts.  

23 

 
 
 
 
 
 
 
 
 
 
 
 
 
The following uncertainties were estimated: 

-  usts,rel, the uncertainty of stability during dispatch. This was estimated based on the -20 °C study. 
The uncertainty describes the possible change during a dispatch at -20 °C lasting for one month. 
-  ults,rel, the uncertainty of stability during storage. This uncertainty contribution was estimated 
based on the -40 °C study apart from imidacloprid, which was estimated from the -20 °C study.  

The results of these evaluations are summarised in Table 6. 

Table 6 Uncertainties of stability during dispatch and storage. usts,rel was calculated for a storage period of 
1 month at -20 °C; ults,rel was calculated for a storage period of 12 months at -40 °C (-20 °C for imidacloprid). 

Pesticide 

AMPA 

Azoxystrobin 

Chlormequat 

Chlorpyrifos 

Cypermethrin 

Deltamethrin 

Diazinon 

Dichlorvos 

α-Endosulfan 

β-Endosulfan 

Endosulfan sulfate 

Sum of α- and β-endosulfan and endosulfan sulfate 
expressed as endosulfan 

Fipronil 

Fipronil sulfone 

Sum of fipronil and fipronil sulfone expressed as fipronil 

Glyphosate 

Imazalil 

Imidacloprid 

Linuron 

Malaoxon 

Malathion 

Sum of malathion and malaoxon expressed as malathion 

Permethrin 

Tebuconazole 

Thiabendazole 

* value obtained at -20 °C. 

24 

usts,rel 

[%] 

0.29 

0.24 

0.08 

0.16 

0.08 

0.16 

0.05 

0.15 

0.22 

0.16 

0.08 

0.07 

0.07 

0.09 

0.07 

0.19 

0.10 

0.10 

0.09 

0.08 

0.10 

0.10 

0.07 

0.13 

0.05 

ults,rel 

[%] 

3.29 

2.21 

1.10 

1.43 

1.15 

1.55 

0.86 

3.08 

4.83 

1.83 

1.14 

1.23 

0.92 

0.95 

0.80 

2.83 

1.12 

1.24* 

1.59 

1.22 

1.09 

1.08 

1.16 

1.27 

0.73 

 
 
Based on the long-term stability study, the uncertainty related to degradation during transport can 
be considered negligible. 

The material showed significant degradation of the pesticides tested at all temperatures above 0 °C. 
Transport on dry ice is necessary. 

After the certification study, the material will  be included in the  JRC's regular stability  monitoring 
programme, to control its further stability. 

25 

 
 
6. Characterisation 

The  material  characterisation  is  the  process  of  determining  the  property  values  of  a  reference 
material. 

This was based on an inter-laboratory comparison of expert laboratories, i.e. the mass fractions of 
pesticides  in  the  material  were  determined  in  different  laboratories  that  applied  different 
chromatographic measurement procedures to demonstrate the absence of a measurement bias. This 
approach converts the systematic bias of each laboratory into a random variable, the combined effect 
of which is reduced by averaging over several laboratories. 

6.1  Selection of participants  

Ten  laboratories  were  selected  based  on  criteria  that  comprised  both  technical  competence  and 
quality management aspects. Each participating laboratory was required to operate a quality system 
and  to  deliver  documented  evidence  of  its  proficiency  in  the  field  of  pesticide  measurements  in 
relevant  matrices  by  submitting  results  for  inter-laboratory  comparison  exercises  or  method 
validation  reports.  Having  a  formal  accreditation  was  not  mandatory,  however  meeting  the 
requirements of ISO/IEC 17025 [3] was obligatory. All measurements were covered by the scope of 
accreditation  of  the  respective  laboratory,  and  the  accreditation  number  is  stated  in  the  list  of 
participants (Section 2). 

6.2  Study setup  

Each  laboratory  received  two  units  of  ERM-BC706  and  was  requested  to  provide  six  independent 
results, corresponding to three results per unit. The units for material characterisation were selected 
using a random stratified sampling scheme covering the whole batch. The sample preparations and 
measurements had to be performed over (a minimum of) two days in order to ensure intermediate 
precision conditions. The water content had to be determined in duplicate for each unit and the results 
were  reported  on  a  dry  mass  basis.  The  laboratories  were  also  requested  to  deliver  the  results 
corrected for recovery.  

Laboratories  were  also  requested to give  estimations of  the  expanded uncertainties  for the mean 
value of the six results. No approach was prescribed for the estimation, i.e. top-down and bottom-up 
[9] were regarded as equally valid procedures. 

6.3  Methods used 

Extraction  and  clean-up  methods,  mainly  QuEChERS  or  modified  versions,  with  different 
quantification approaches were used to characterise the material. Some pesticides were analysed by 
a  combination  of  GC  and  LC  methods  while  others  were  exclusively  analysed  using  one  of  the 
methods. The combination of results originating from methods which target the same measurand but 
are based on different measurement principles, mitigates the undetected method bias. 

All methods used during the characterisation study are summarised in Annex E. The laboratory code 
(e.g. L01-GC-MS/MS) is a random number and does not correspond to the order of laboratories in 
Section 2.  The  lab-method  code  consists  of  a  number  assigned  to  each  laboratory  (e.g.  L01)  and 
abbreviation of the measurement used method (e.g. GC-MS/MS). An extra letter (e.g L01a, L01b) was 
assigned  to  laboratories  providing  data  for  particular  pesticides  using  more  than  one  method  of 
determination. 

26 

 
6.4  Dry mass determination  

For all measurements carried out during characterisation the protocol described in Section 9.5 for dry 
mass determination was applied. 

6.5 

Evaluation of results 

The characterisation study resulted in a minimum of four datasets per pesticide. All individual results 
of the participating laboratories, grouped per pesticide, are displayed in tabular and graphical form in 
Annex F. 

Technical evaluation 

6.5.1 
The obtained data were initially checked for compliance with the requested instructions and for their 
validity based on technical reasons. The following criteria were considered during the evaluation: 

- 

compliance with the instructions given: sample preparations and measurements performed 
on two days, and water content determination 

-  absence of values given as below limit of quantification (LOQ)  

-  method performance, MQC sample measured to confirm absence (<LOQ) of target pesticides 

-  according to SANTE/12682/2019 [6] the method repeatability should be not higher than  

20 %.  

Based on the above criteria all datasets were technically valid with the exception of the following 
cases: L04 reported recovery values of the MQC sample for dichlorvos outside the laboratory's normal 
acceptable range. L06 reported nine out of the total pesticides list as the others did not fulfil the 
specifications given by DG SANTE [5] for validated methods. For L03 and L10 method repeatability 
exceeded 20 % for malaoxon and endosulfan sulfate, respectively. The results from the mentioned 
pesticides  from  these  laboratories  are  therefore  not  included  in  the  final  evaluation.  The  sum  of 
endosulfan, fipronil  and malathion are calculated  based on the individual compound  results given 
from  the  participants. Datasets  where  one  or  more components  of  the  sum  were  not  reported  or 
accepted, are not included in the calculations. It should be noted that not all laboratories submitted 
results for all the pesticides. 

Statistical evaluation 

6.5.2 
The datasets which were accepted based on technical reasons, were tested for normality of dataset 
means using kurtosis/skewness tests and normal probability plots and additionally tested for 
outlying means using the Grubbs test and using the Cochran test for outlying standard deviations 
(both at a 99 % confidence level). Standard deviations within (swithin) and between (sbetween) 
laboratories were calculated using one-way ANOVA. The results of these evaluations are shown in 
Table 7. 

27 

 
 
 
 
Table 7: Statistical evaluation of the technically accepted datasets  for ERM-BC706.  p: number of 
technically valid datasets 

Pesticide 

AMPA 

Azoxystrobin 

Chlormequat 

Chlorpyrifos 

Cypermethrin 

Deltamethrin 

Diazinon 

Dichlorvos 

α-Endosulfan 

β-Endosulfan 

Endosulfan sulfate 

Sum of α- and β-
endosulfan and 
endosulfan sulfate 
expressed as 
endosulfan 

Fipronil 

Fipronil sulfone 

Sum of fipronil and 
fipronil sulfone 
expressed as fipronil 

Glyphosate 

Imazalil 

Imidacloprid 

Linuron 

Malaoxon 

Malathion 

Sum of malathion 
and malaoxon 
expressed as 
malathion 

Permethrin 

Tebuconazole 

Thiabendazole 

p 

4 

10 

6 

11 

9 

9 

12 

7 

9 

9 

8 

8 

11 

9 

9 

7 

10 

9 

10 

7 

10 

6 

11 

11 

10 

Outliers 

Means 

Varian-
ces 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1 

1 

2 

1 

0 

0 

0 

1 

1 

1 

2 

1 

1 

0 

0 

0 

2 

0 

1 

0 

0 

2 

2 

2 

1 

28 

Normally 
distributed 

insufficient 
data 

Statistical parameters 

Mean 

s 

sbetween 

swithin 

[mg/kg] 

[mg/kg] 

[mg/kg] 

[mg/kg] 

0.084 

0.023 

0.023 

0.011 

normal 

0.075 

0.014 

0.014 

0.004 

normal 

2.060 

0.464 

0.462 

0.117 

normal 

2.432 

0.352 

0.349 

0.127 

normal 

3.659 

0.638 

0.628 

0.278 

normal 

3.790 

0.928 

0.919 

0.318 

normal 

0.385 

0.064 

0.064 

0.017 

normal 

0.284 

0.098 

0.097 

0.021 

normal 

0.093 

0.019 

0.017 

0.007 

normal 

0.274 

0.043 

0.042 

0.016 

normal 

0.356 

0.081 

0.079 

0.025 

normal 

0.719 

0.115 

0.108 

0.036 

normal 

0.417 

0.046 

0.044 

0.031 

normal 

0.594 

0.080 

0.078 

0.043 

normal 

0.982 

0.127 

0.125 

0.055 

normal 

1.203 

0.221 

0.218 

0.089 

normal 

0.226 

0.047 

0.047 

0.019 

normal 

0.044 

0.010 

0.010 

0.003 

normal 

0.514 

0.084 

0.082 

0.038 

normal 

0.011 

0.002 

0.002 

0.001 

normal 

9.674 

1.512 

1.416 

1.165 

normal 

9.034 

1.414 

1.382 

0.795 

normal 

0.404 

0.101 

0.101 

0.030 

normal 

0.041 

0.009 

0.009 

0.002 

normal 

0.409 

0.063 

0.063 

0.017 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
The  laboratory  means  follow  normal  distributions  apart  from  AMPA,  due  to insufficient  data  sets. 
None of the data contains outlying means. The datasets are therefore consistent and the mean of 
laboratory means is a good estimate of the true value. Standard deviations between laboratories are 
considerably larger than the standard deviation within laboratories, showing that confidence intervals 
of replicate measurement results are unsuitable as estimates of measurement uncertainty. 

The statistical evaluation flags outlying variance for a number of pesticides. These variances were 
identified mainly from L02, L07 and L09. This merely reflects the fact that different methods have 
different intrinsic variability. As all measurement methods were found technically sound, all results 
were retained. 

It  should  be  borne  in  mind  that  the  methods  used  in  the  characterisation  are  methods  routinely 
applied for measuring pesticides in wheat flour. The agreement of results from different methods 
demonstrates that the processing did not affect any properties relevant to these methods and that 
ERM-BC706 behaves like a real sample. 

The measurement value for AMPA is close to or below LOQ, and an insufficient number of datasets 
(only 4) was reported. Furthermore, the combined uncertainty for dichlorvos exceeded 20%. These 
two pesticides are therefore not evaluated for certification, and the data are given only as indicative 
values.  

The uncertainty related to the characterisation is estimated as the standard error of  the  mean of 
laboratory means (s/√p) (Table 8). 

29 

 
 
 
Table 8 Uncertainty of characterisation for ERM-BC706 

Pesticide 

AMPA 

Azoxystrobin 

Chlormequat 

Chlorpyrifos 

Cypermethrin 

Deltamethrin 

Diazinon 

Dichlorvos 

α-Endosulfan 

β-Endosulfan 

Endosulfan sulfate 

Sum of α- and β-endosulfan and endosulfan 
sulfate expressed as endosulfan 

Fipronil 

Fipronil sulfone 

Sum of fipronil and fipronil sulfone expressed 
as fipronil 

Glyphosate 

Imazalil 

Imidacloprid 

Linuron 

Malaoxon 

Malathion 

Sum of malathion and malaoxon expressed 
as malathion 

Permethrin 

Tebuconazole 

Thiabendazole 

p 

4 

10 

6 

11 

9 

9 

12 

7 

9 

9 

8 

8 

11 

9 

9 

7 

10 

9 

10 

7 

10 

6 

11 

11 

10 

Mean 
[mg/kg] 

s 
[mg/kg] 

uchar 
[mg/kg] 

0.084 

0.075 

2.060 

2.432 

3.659 

3.790 

0.385 

0.284 

0.093 

0.274 

0.356 

0.719 

0.417 

0.594 

0.982 

1.203 

0.226 

0.044 

0.514 

0.011 

9.674 

9.034 

0.404 

0.041 

0.409 

0.023 

0.014 

0.464 

0.352 

0.638 

0.928 
0.064 

0.098 

0.019 

0.043 

0.081 

0.115 

0.046 

0.080 

0.127 

0.221 

0.047 

0.010 
0.084 

0.002 

1.512 

0.0115 

0.0045 

0.1896 

0.1063 

0.2127 

0.3093 

0.0186 

0.0371 

0.0062 

0.0142 

0.0285 

0.0405 

0.0139 

0.0266 

0.0422 

0.0836 

0.0150 

0.0033 

0.0265 

0.0007 

0.4780 

1.414 

0.5773 

0.101 

0.009 

0.063 

0.0305 

0.0028 

0.0200 

30 

 
 
7. Value Assignment 

Certified and indicative values were assigned. 

Certified values are values that fulfil the highest standards of accuracy. Procedures at JRC Directorate 
F recommend pooling of at least six datasets to assign certified values. Full uncertainty budgets in 
accordance with ISO 17034 [1] and ISO Guide 35 [2] were established. 

Indicative values are values where either the uncertainty is deemed too large or too few independent 
datasets were available to allow certification. Uncertainties are evaluated according to the same rules 
as for certified values. 

7.1  Certified values and their uncertainties 

The unweighted mean of the means of the accepted datasets as shown in  

9 was assigned as certified value for each parameter.  

The  assigned  uncertainty  consists  of  uncertainties  relating  to  characterisation  (uchar),  potential 
between-unit inhomogeneity (ubb), potential degradation during transport (usts), and long-term storage 
(ults). The uncertainty related to degradation during transport was found negligible. These different 
contributions were combined in order to estimate the relative expanded uncertainty of the certified 
value (UCRM, rel) with a coverage factor k given as: 

UCRM, rel = k  ∙  (cid:3495)ubb, rel

2

2
+ults, rel

2
+uchar, rel

Equation 6 

-  uchar was estimated as described in Section 6.5.2 

-  ubb was estimated as described in Section 4.1 

-  ults was estimated as described in Section 5.3 

The JRC’s procedures for assigning uncertainties to certified values stipulate that for more than five 
effective degrees  of freedom a coverage (k) factor of 2 can be chosen. This was the case for all 
pesticides for which a certified value could be established. Therefore, a k-factor of 2 was applied to 
obtain  the  expanded  uncertainties.  The  certified  values  and  their  uncertainties  are  summarised  in 
Table 9. 

31 

 
  
 
 
 
 
Table 9: Certified values and their uncertainties for ERM-BC706 

Pesticide 

Azoxystrobin 

Chlormequat 3) 

Chlorpyrifos 

Cypermethrin 4) 

Deltamethrin  4) 

Diazinon 

α-Endosulfan 4) 

β-Endosulfan 4) 

Endosulfan sulfate 4) 

Sum of α- and β-endosulfan 
and endosulfan sulfate 
expressed as endosulfan 4) 

Certified 
value1) 

[mg/kg] 

0.075 

2.1 

2.43 

3.7 

3.8 

0.38 

0.093 

0.27 

0.36 

uchar, rel 

ubb, rel 

ults, rel 

UCRM, rel 

UCRM 

2) 

[%] 

[%] 

[%] 

[%] 

[mg/kg] 

6.06 

9.20 

4.37 

5.81 

8.16 

4.84 

6.62 

5.18 

8.00 

1.25 

0.71 

0.83 

0.76 

1.26 

2.21 

1.10 

1.43 

1.15 

1.55 

0.55 

0.86 

1.75 

2.35 

0.96 

4.83 

1.83 

1.14 

13.4 

19.4 

9.9 

13.7 

18.5 

10.4 

17.2 

14.6 

16.8 

0.010 

0.4 

0.23 

0.5 

0.7 

0.04 

0.016 

0.04 

0.06 

0.72 

5.63 

0.98 

1.23 

12.5 

0.09 

Fipronil 

Fipronil sulfone 

0.42 

0.59 

3.33 

4.48 

1.21 

0.43 

0.92 

0.95 

9.6 

10.1 

Sum of fipronil and fipronil 
sulfone expressed as fipronil 

Glyphosate 3) 

Imazalil 

Imidacloprid 3) 

Linuron 3) 

Malaoxon 

Malathion 

Sum of malathion and 
malaoxon expressed as 
malathion 

Permethrin 

Tebuconazole 

0.04 

0.06 

0.09 

0.19 

0.04 

0.007 

0.06 

0.0015 

1.0 

0.98 

4.30 

0.61 

0.80 

9.2 

1.20 

0.23 

0.044 

0.51 

0.0112 

6.95 

1.79 

2.83 

6.63 

7.47 

5.16 

6.22 

1.56 

1.88 

1.17 

1.80 

1.12 

1.24 

1.59 

1.22 

9.7 

4.94 

1.08 

1.09 

15.8 

17.7 

15.8 

11.7 

13.4 

11.4 

9.0 

6.38 

1.08 

1.08 

14.4 

1.3 

0.40 

7.56 

0.62 

1.16 

0.041 

6.89 

1.73 

1.27 

17.3 

14.6 

0.07 

0.006 

0.41 

Thiabendazole 3) 

0.81 
1) Reported on dry mass basis (Section 9.5) and corrected for recovery 
2) Expanded (k = 2) and rounded uncertainty; uncertainties are always rounded up [13] and in a way that the 
rounding error corresponds to 3 % to 30 % of the uncertainty 
3) As obtained by liquid chromatography/triple quadrupole mass spectrometry 
4)  As  obtained  by  extraction  with  acetonitrile/water  and  gas  chromatography/triple  quadrupole  mass 
spectrometry 

12.2 

0.05 

4.90 

0.73 

32 

 
7.2 

Indicative values and their uncertainties 

Indicative values were assigned for AMPA and dichlorvos. The value for AMPA is close to the LOQ with 
only four laboratories submitting results. For both pesticides, the combined expanded uncertainty is 
deemed too high to allow for certification. An indicative value may not be used as certified value. The 
uncertainty budgets were set up as for the certified values and are listed together with the assigned 
values in Table 10. For AMPA a k-factor of 3.18 was used due to the limited degrees of freedom. 

Table 10: Indicative values and their uncertainties for ERM-BC706 

Pesticide 

Aminomethylphosphonic acid 
(AMPA)2) 

Indicative 
value 1) 

[mg/kg] 

uchar, rel 

ubb, rel 

ults, rel 

UCRM, rel 

UCRM 

[%] 

[%] 

[%] 

[%] 

[mg/kg] 

0.08 

13.73 

3.93 

3.29 

47.9 

0.043) 

Dichlorvos 

0.28 

13.07 

2.33 

3.08 

28.1 

0.084) 

1) Reported on dry mass basis (Section 9.5) 
2) As obtained by liquid chromatography/triple quadrupole mass spectrometry 
3) Expanded (k = 3.18) and rounded uncertainty; uncertainties are always rounded up [13] and in a way that the 
rounding error corresponds to 3 % to 30 % of the uncertainty 
4) Expanded (k = 2) and rounded uncertainty; uncertainties are always rounded up [13] and in a way that the 
rounding error corresponds to 3 % to 30 % of the uncertainty 

33 

 
 
 
8. Metrological traceability and commutability 

8.1  Metrological traceability 

Identity 

Pesticides are chemically, clearly defined substances. Their identity was confirmed by retention time 
elution from gas or liquid chromatography in combination with mass spectrometry. The participants 
used  different  methods  for  the  sample  preparation  as  well  as  for  the  final  determination, 
demonstrating absence of measurement bias. The measurands are therefore structurally defined and 
independent of the measurement method when the determination is based on different techniques. 
This  is  valid  for  azoxystrobin,  chlorpyrifos,  diazinon,  fipronil,  fipronil  sulfone,  imazalil,  malathion, 
malaoxon, permethrin and tebuconazole. Meanwhile, the identity of the measurand is operationally 
defined in those cases where exclusively LC-MS/MS (chlormequat, glyphosate, imidacloprid, linuron 
and  thiabendazole)  or  GC-MS/MS  (cypemethrin,  deltamethrin,  endosulfan,  endosulfan  sulfate)  is 
applied.  

Quantity value 

Only validated methods were used during the characterisation study. Different calibrants of (known 
purity and) specified traceability of their assigned values were used. Investigation of the method and 
measurement  details  of  the  individual  results  show  that  all  relevant  input  parameters  of  each 
technically  accepted  dataset  have  been  properly  calibrated.  All  technically  accepted  datasets  are 
therefore traceable to the same reference, namely the SI. This traceability to the same reference is 
also  confirmed  by  the  agreement  of  results  within  their  respective  uncertainties.  As  the  assigned 
values are combinations of agreeing results individually traceable to the SI, the assigned quantity 
values themselves are also traceable to the SI as well. 

8.2  Commutability 

The concept of commutability of a reference material is defined by the VIM [14] as: 

“property of a reference material, demonstrated by the closeness of agreement between the relation 
among  the  measurement  results  for  a  stated  quantity  in  this  material,  obtained  according  to  two 
given measurement procedures, and the relation obtained among the measurement results for other 
specified materials” 

ERM-BC706 was produced from wheat, which was field treated with pesticide formulations and the 
harvested  kernels  were  further spray-contaminated. The  wheat material  was processed  by milling 
and mixing. The CRM mimics as much as possible routine samples of wheat flour. Nevertheless, one 
has to bear in mind that steps during the processing such as spraying the pesticides on the kernels 
may have influenced the extractability. Furthermore, the particle size can influence the extraction of 
pesticides, and may lead to a significant measurement bias. 

For samples other than wheat flour, it is the responsibility of the CRM user to assess the suitability 
of the reference material. 

34 

 
 
 
 
9. Instructions for use 

9.1  Safety information 

The usual laboratory safety measures apply.  

9.2  Storage conditions 

The material should be stored at (-40 ± 5) °C in the dark. Care should be taken to avoid any change 
of the moisture content once the units are open, as the material is potentially hygroscopic. The user 
should close any unit immediately after taking a sample.  

Note that the European Commission cannot be held responsible for changes that may happen during 
storage of the material at the customer's premises, especially of opened samples. 

9.3 

Preparation and use of the material 

The material must be re-homogenised by repeatedly turning over the unit and shaking for 2 min prior 
to analysis. 

9.4  Minimum sample size 

The minimum sample size representative for all measurands is 1 g.  

9.5  Dry mass correction 

Dry mass determination shall be carried out on a separate portion of at least 1 g, by drying in an 
oven at (103 ± 2) °C until constant mass (separate weighing at time intervals of 30 min should not 
differ  by  more  than  5  mg)  is  attained.  Weighing  of  the  samples  for  dry  mass  determination  and 
weighing  for  the  analysis  shall  be  done  at  the  same  time  to  avoid  differences  due  to  possible 
absorption of moisture by the material. 

9.6  Use of the certified value 

The  intended  use  of  this  material  is  to  assess  method  performance,  i.e.  for  checking  accuracy  of 
measurement  results/calibration.  As  with  any  reference  material,  it  can  be  used  for  establishing 
control charts or validation studies. 

Use as a calibrant 

It is not recommended to use this matrix material as calibrant. If used nevertheless, the uncertainty 
of the certified value shall be taken into account in the estimation of the measurement uncertainty. 

Comparing a measurement result with the certified value 

A result is unbiased if the combined standard uncertainty of measurement and certified value covers 
the difference between the certified value and the measurement result (see also ERM  Application 
Note 1 [15]). 

When assessing the method performance, the measured values of the CRMs are compared with the 
certified values. The procedure is summarised here: 

-  Calculate  the  absolute  difference  between  mean  measured  value  and  the  certified  value 

(Δmeas). 

35 

 
 
-  Combine  the  measurement  uncertainty  (umeas)  with  the  uncertainty  of  the  certified  value 

(uCRM): uΔ = (cid:3495)umeas

2

2
 + uCRM

-  Calculate  the  expanded  uncertainty  (U)  from  the  combined  uncertainty  (u)  using  an 
appropriate coverage factor, corresponding to a level of confidence of approximately 95 %. 

- 

If Δmeas  U then no significant difference exists between the measurement result and the 
certified value, at a confidence level of approximately 95 %. 

Use in quality control charts 

The material(s) can be used for quality control charts. Using CRMs for quality control charts has the 
added value that a trueness assessment is built into the chart. 

36 

 
 
 
10. Acknowledgements  

The  authors  would  like  to  acknowledge  the  support  received  from  colleagues  of  JRC  for  the 
processing,  organising  of  stability  studies,  measuring,  reviewing  of  the  certification  project  and 
distribution of this CRM. Furthermore, the authors would like to thank Lise Nistrup Jørgensen, Dept. 
of  Agroecology,  Aarhus  University,  Slagelse,  DK  for  supplying  the  wheat,  and  FMC  Agricultural 
Solutions A/S, Hørsholm (DK) for the generous supply of malathion formulation. 

Finally,  the  authors  would  like  to  thank  the  experts  of  the  Reference  Material  Review  Panel  Tuija 
Pihlström  (National  Food  Agency,  SE)  and  Katrin  Vorkamp  (Aarhus  University,  DK)  for  their 
constructive comments and the external review of the certification report and certificate. 

37 

 
11. References

1  

2  

3  

4  

5  

6  

7 

8  

9  

ISO 17034:2016, General requirements for the competence of reference material producers, 
International Organization for Standardization, Geneva, Switzerland 

ISO Guide 35:2017, Reference materials – Guidance for characterization and assessment of 
homogeneity and stability, International Organization for Standardization, Geneva, Switzerland 

ISO/IEC 17025:2017, General requirements for the competence of testing and calibration 
laboratories, International Organization for Standardization, Geneva, Switzerland 

Regulation (EC) No 396/2005 of the European Parliament and of the Council of 23 February 
2005 on maximum residue levels of pesticides in or on food and feed of plant and animal 
origin and amendments, Brussels, Belgium.  

European Commission, Directorate General for Health And Food Safety, Guidance document on 
analytical quality control and method validation procedures for pesticide residues and analysis 
in food and feed (SANTE/111813/2017), Brussels, Belgium 
Main changes introduced in document SANTE/12682/2019 with respect to the previous   
version    (document SANTE/11813/2017)  https://www.eurl-
pesticides.eu/userfiles/file/EurlALL/AqcGuidance_SANTE_2019_12682.pdf (last assessed on 
28/03/2022) 

K Maštovská, S. J. Lehotay; Evaluation of common organic solvents for gas chromatographic 
analysis and stability of multiclass pesticide residues, Journal of Chromatography A, 1040 
(2004) 259–272 

M. L. Feo, E Eljarrat, Chapter 9. Determination of Pyrethroid Insecticides in Environmental 
Samples by GC-MS and GC-MS-MS, TrAC Trends in Analytical Chemistry, July 2010 

ISO/IEC Guide 98-3:2008, Uncertainty of measurement – Part 3: Guide to the Expression of 
Uncertainty in Measurement (GUM 1995), International Organization for Standardization, 
Geneva, Switzerland 

10   T.P.J. Linsinger, J. Pauwels, A.M.H. van der Veen, H. Schimmel, A. Lamberty, Homogeneity and 

stability of reference materials, Accred. Qual. Assur. 6 (2001) 20-25 

11   A. Lamberty, H. Schimmel, J. Pauwels, The study of the stability of reference materials by 

isochronous measurements, Fres. J. Anal. Chem. 360 (1998) 359-361 

12   T.P.J. Linsinger, J. Pauwels, A. Lamberty, H.G. Schimmel, A.M.H. van der Veen, L. Siekmann, 

Estimating the uncertainty of stability for matrix CRMs, Fres. J. Anal. Chem. 370 (2001) 183-
188 

13   DIN 1333:1992-02, Zahlenangaben, Deutsches Institut für Normung e.V., Berlin, Germany 

14  

15 

ISO/IEC Guide 99:2007, International vocabulary of metrology – Basic and general concepts 
and associated terms (VIM), International Organization for Standardization, Geneva, 
Switzerland 

T.P.J. Linsinger, ERM Application Note 1: Comparison of a measurement result with the certified 
value, https://crm.jrc.ec.europa.eu/e/132/User-support-Application-Notes (last accessed on 
28/03/2022) 

38 

 
 
39 

 
 
Annex A. List of pesticides for certification in ERM-BC706 with some characteristics 

Pesticide 

Chemical class  

Application 

CAS number 

Treatment 

On field 

Fortified 

Chemical structure 

Molecular 
weight 

MRL1 
[mg/kg] 

Regulation 
(EU)2 

Aminomethyl 
phoshonic acid 
(AMPA) 

glyphosate 
degradation products  

1066-51-9 

Azoxystrobin 

aryloxypyrimidines 

fungicide 

131860-33-8 

Chlormequat3 

organochlorides 

Chlorpyrifos 

organophosphates 

plant growth 
regulator 

7003-89-6 

insecticide, 
nematicide 

2921-88-2 

Cypermethrin4  

pyrethroides 

insecticide 

52315-07-8  
(undefined 
stereochemistry) 

Deltamethrin5 

pyrethroides 

insecticide 

52918-63-5 

Diazinon 

organophosphates 

insecticide 

333-41-5  

Dichlorvos 

organophosphates 

insecticide 

62-73-7 

x 

x 

x 

x 

39 

x 

x 

x 

x 

x 

186.2 

0.01* 

Not 
regulated 

403.4 

0.5 

2019/552 

122.6 

7.0 

2020/1565 

350.6 

0.01* 

2020/1085 

416.3 

2.0 

2017/626 

505.2 

1.0 

2018/832 

304.4 

0.01* 

2013/834 

221.0 

0.01* 

839/2008 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Pesticide 

Chemical class  

Application 

CAS number 

Treatment 

On field 

Fortified 

Chemical structure 

Molecular 
weight 

MRL1 
[mg/kg] 

Regulation 
(EU)2 

Endosulfan6  

organochlorides 

insecticide 

Endosulfan 
sulfate6 

endosulfan 
degradation products 

959-98-8  
(α-endosulfan) 
33213-65-9 
(β-endosulfan) 

1031-07-8 

Fipronil7 

pyrazoles 

insecticide 

120068-37-3 

x 

Fipronil sulfone7 

fipronil degradation 
products 

120068-36-2 

Glyphosate 

organophosphates 

herbicide 

1071-83-6 

x 

Imazalil8 

imidazoles 

fungicide 

35554-44-0 

x 

x 

x 

x 

x 

406.9 

422.9 

437.1 

453.1 

0.05* 

310/2011 

0.005* 

2019/1792 

169.1 

10.0 

293/2013 

297.2 

0.01* 

2020/856 

Imidacloprid 

neonicotinoides 

insecticide 

138261-41-3 

x 

255.7 

0.1 

2014/491 

40 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Pesticide 

Chemical class  

Application 

CAS number 

Treatment 

On field 

Fortified 

Chemical structure 

Molecular 
weight 

MRL1 
[mg/kg] 

Regulation 
(EU)2 

Linuron 

organochlorides 

herbicide 

330-55-2 

Malaoxon9 

malathion 
degradation products 

1634-78-2 

Malathion9 

phosphorodithioates  

insecticide 

121-75-5 

x 

Permethrin10 

pyrethroides 

insecticide 

52645-53-1 

Tebuconazole 

triazoles 

fungicide 

107534-96-3  

x 

Thiabendazole 

benzimidazoles 

fungicide 

148-79-8 

x 

x 

x 

x 

249.1 

0.01* 

2019/58 

314.3 

330.4 

8.0 

2015/399 

391.3 

0.05* 

2017/623 

307.8 

0.3 

2018/1514 

201.2 

0.01* 

2017/1164 

1MRL in wheat (last accessed March 2022) 
2EU Regulation amending relevant annexes of Regulation (EU) 396/2005 
3Chlormequat is defined as sum of chlormequat and its salts, expressed as chlormequat-chloride 
4Cypermethrin is defined as cypermethrin including other mixtures of constituent isomers 
(sum of isomers) 
5Deltamethrin is defined as cis-deltamethrin 

6Endosulfan is defined as the sum of α- and β-endosulfan and endosulfan sulfate 
expressed as endosulfan 
7Fipronil is defined as the sum of fipronil and sulfone metabolite expressed as fipronil 
8Imazalil is defined as imazalil (any ratio of constituent isomers) 
9Malathion is defined as the sum of malathion and malaoxon expressed as malathion 
10Permethrin is defined as permethrin (sum of isomers) 
* Indicates lower limit of analytical determination 

41 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Annex B. Results of the homogeneity measurements.  

Values are illustrated  as mean  mass fractions or normalised values with standard 
deviation  error  bars  of  pesticide  obtained  from  the  analysis  of  3  subsamples  per 
unit of ERM-BC706.  

42 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
43 

 
 
 
 
 
44 

 
 
 
 
 
 
 
45 

 
 
 
 
 
Annex C: Results of the short-term stability measurements (+4 0C).  

Graphs provide individual results (6 replicates per time point) to better illustrate the 
presence of, if any, outliers. A linear regression trendline is plotted whenever a trend 
is statistically significant. 

46 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
47 

 
 
 
 
 
48 

 
 
 
 
49 

 
 
 
Annex D. Results of the long-term stability results (-40 oC for 12 months).  

Graphs provide individual results (6 replicates per time point) to better illustrate the 
presence, if any, of outliers. A linear regression trendline is plotted whenever a trend 
is statistically significant.  

50 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
51 

 
 
 
52 

 
 
 
53 

 
 
 
Annex  E.  Summary of analytical methods used for characterisation of ERM-BC706 

Table E.1 Details of analytical methods, as given by the laboratories where gas chromatography was applied for the determination of 
pesticides in wheat flour. 

01 

02 

03 

04 

05 

LABO-
RATORY 
CODE 

Sample 
intake  
(g) 

Internal Standard 

Extraction 

Clean up 

5  Azoxystrobin-D4, 
chlorpyrifos-D10, 
imazalil-D5 

Quechers, Acetonitril/Water 
(1:1), shaking for 15 min, 
centrifugation 

5  Diazinon-D10 

Addition of water and 
acetonitrile, agitation with 
ultra turax, centrifugation 
and spike of Il-IS  

5 

Triphenylphosphate  Water/ACN, 10 + 10 mL 

salting out, with MgSO4, 
NaCl, Sodiumcitrate 
buffer, centrifugation, 6-
ml Aliquot, shaking with 
PSA/MgSO4 centrifugation, 
1ml acidified by formic 
acid 
Use of CAPTIVA EMR SPE 
cartridge, Concentration 
under nitrogen flux and 
re-constitution with 
diisopropyl ether 
QuEChERS - PSA/ODS  150 
mg/150 mg 

Injection 
technique 

Stationary phase and 
dimensions analytical 
column 

Analytical 
column  

Calibration  

Ionisation 
technique 

Mass 
analyser/ 
detector 

Split-
splitless 

      1,4-bis-
(Dimethylsiloy)phenylen-
dimethylpolysiloxan, ~38 
m+IG, 0.25 mm, 0.25 µm 

Rxi-5Sil ms 
15m + 10m 
Rxi-XLB  

Calibration 
curve 

EI 

Triple 
quadrupole 

Split-
splitless 

HP-5MS (30 m, 0.25mm, 
0,25 µm 

Agilent HP-
5MS 

Procedural 
calibration 

EI 

Triple 
quadrupole 

5 

13C6-
Hexachlorobenzene, 
D10-Chlorpyrifos, 
D6-Pirimicarb, D6-
Pirimiphos-methyl, 
Triphenylphosphate 

1  Azoxystrobin-D4 
Chlorpyrifos-D10 
13C6-Cypermethrin 
Deltamethrin-D5 
Diazinon-D10 
Dichlorvos-D6 
13C9-endosulfan II 
13C9-Endosulfan 
sulfate 
13C4-Fipronil 
Malathion-D10 
Permethrin-D5 
Tebucaonazole-D6 

Citrate buffered Quechers 
extraction with acetonitrile 

dSPE with PSA and C18e 

On-column 

5% Phenyl, 95% 
dimethylpolysiloxane 
(30m, 0.25mm, 0.25um) 

Agilent 
Technologies 
HP-5MS UI 

Split-
splitless 

Proprietary (30m, 
0.25mm, 0.2 um) 

Restek RTX-
CLPesticides2 

Calibration 
curve 

EI 

EI 

Triple 
quadrupole 

 Triple 
quadrupole 

Citrate buffered extraction 
with acetonitrile 

Supelco C18 SPE and 
Supelco PSA SPE  

Split-
splitless 

(20 m, 0.25 mm, 0.25 µm) 

TG-SQC 

Response 
factor 

EI 

Triple 
quadrupole 

54 

 
 
 
 
 
 
 
 
 
 
 
 
LABO-
RATORY 
CODE 

Sample 
intake  
(g) 

Internal Standard 

Extraction 

Clean up 

Injection 
technique 

Stationary phase and 
dimensions analytical 
column 

Analytical 
column  

Calibration  

Ionisation 
technique 

Mass 
analyser/ 
detector 

06 

07 

08 

09 

10 

5 

Triphenylphosphate 

5 

10 

Triphenylphosphate 
Atrazine-d5 

2 

5 

Triphenylphosphate, 
chlorobenzilate 

QuEChERS: 5 H2O/10 mL 
Acetonitrile 1% Acetic Acid, 
1ppm Tphp. 1h freezing. 5 g 
MgSO4/AcONa (4:1). Shake 
1', centrifuge 4'/4000 rpm. 
Ceramic homogenizer, 10 
mL water/10 mL acetonitrile. 
mechanically shaken 5 min. 
4 g MgSO4, 1 g NaCl, 1 g 
Na3 citrate dihydrate and 
0.5 g Na2H cirate 
sesquihydrate, shaken 1 
min, centrifuged 10 min at 
4500 rpm. 8 ml frozen out. 
Centrifuged 5 °C, 10 min 
4500 rpm. 
QuEChERS 

10 mL of water, automatic 
shaker 10 min,  10 mL of 
acetonitrile and QuEChERS 
citrate salts, automatic 
shaker 10 min 
10 mL water, extraction with 
10 mL of acetonitrile, 
manual shaking 3 min. 

4mL of acetonitrile extract 
with 1,0g MgSO4/0,6g PSA 
/ 0,4g C18. Shake and 
centrifuge 4'/4000 rpm. 

Split-
splitless 

Crossbond, similar to 5% 
diphenyl/95% dimethyl 
polysiloxane (30m, 
0.25mm, 0.25um) 

Restek Rxi-
5Sil MS 

Calibration 
curve 

EI 

Triple 
quadrupole 

8 ml extract, 900 mg PSA 
and 900 mg MgSO4, 
shaken 30 seconds and 
centrifuged five min at 
4500 rpm 

Split-
splitless 

DB5 (30 m, 0.25mm, 0.25 
um) 

Thermo 
Scientific  
5SILMS 
TG
w/5m 
‐
safeguard 

Calibration 
curve 

EI 

Triple 
quadrupole 

None 

Split-
splitless 

Centrifugation, freezing-
out, d-SPE (PSA) clean-up 

Split-
splitless 

Sílice fundida & 5% 
Diphenyl-Polysiloxane 
(0m, 0.25 mm, 0.25 um) 
(30 m x 0,25 mm 0,25 
µm) 

Matrix 
matched 

HP-5ms Ultra 
Inert 
Columns  
Zebron ZB-50   Calibration 

curve 

Outsalting with sodium 
chloride - sodium citrate - 
sodium hydrogen citrate 
and magnsulphate, dSPE 
purification with PSA, 
freezing out 

5%-phenyl-
methylpolysiloxane (15m, 
0.25mm, 0.25um) 

HP-5MS 

EI 

EI 

EI 

Triple 
quadrupole 

Triple 
quadrupole 

Triple 
quadrupole 

55 

 
 
 
 
 
 
 
 
 
 
 
 
 
LAB 
CODE 
1 

2 

3 

4 

5 

6 

7 

8 

9 

Table E.2: m/z transitions used for quantitative (in bold) and qualitative purposes for the different target compounds (gas 
chromatography) 

Azoxystrobin  

Chlorpyrifos 

Cypermethrin  

Deltamethrin 

Diazinon  

Dichlorvos 

α-Endosulfan,  

β-Endosulfan 

Endosulfan sulfate 

313.8 -> 257.8 
198.9 -> 171.0 
196.9 -> 169.0 

163.0 -> 91.0 
163.0 -> 127.0 
164.9 -> 91.0 

181.0 -> 152.1 
250.7 -> 172.0 
252.9 -> 93.0 

137.1 -> 84.0 
137.1 -> 54.0 
199.1 -> 93.0 

194.9 -> 125.0 
238.8 -> 204.0 
262.8 -> 192.9 

206.9 -> 172.0 
194.9 -> 158.9 
194.9 -> 124.9 

271.9 -> 237.0 
273.8 -> 236.9 
273.8 -> 238.9 

344.1 -> 329.0 
238.8 -> 204.0 
262.8 -> 192.9 
D4 348.1 -> 
333.0 
348.1 -> 186.9 
391.9 -> 348.9 

197 -> 169 
199 -> 171 

163 -> 127 
163 -> 91 

253 -> 93 
181 -> 152 

137 -> 84 
137 -> 54 

195 -> 125 
195 -> 159 

195 -> 159 
207 -> 172 

272 -> 237 
274 -> 239 

196.9 -> 169.0 
313.8 -> 257.8 

181.0 -> 152.1 
163.0 -> 127.0 

252.9 -> 174.0 
253.0 -> 93.0 

137.1 -> 84.0 
304.0 -> 179.0 

241.0 -> 206.0 
241.0 -> 170.0 

206.9 -> 172.0 
194.9 -> 124.9 

271.9 - 237.0 
229.0 - 194.0 

314 -> 258 
314 -> 286 
D10 324 -> 260 
324 -> 292 
315.9->259.9 
313.9->257.7 
D10 324.1-
>259.8 
326.0->261.8 

314.00 -> 
258.00 
314.00 -> 286.00 

344.0 -> 329.0 
388.0 -> 345.0 
D4 348.0 -> 
332.0 
348.0 -> 156.0 

344.00 -> 329.00 
344.00 -> 156.00 

163 -> 127 
180.8 -> 151.8 

253 -> 174 
253 -> 77 
253 -> 93 

241 -> 206 
195 -> 125 
339 -> 160 

241 -> 206 
195 -> 125 
339 -> 160 

181.1->151.9 
181.1->152.6 
13C6 187.2->157.8 
215.2->115.8 

181.0 -> 152.2 
209.1 -> 88.9 
D4 185.0 -> 156.4 
214.1 -> 146.4 

179.1->136.9 
304.1->179.9 
D10 183.3->123 
183.3->123.8 

184.9 -> 93.0 
184.9 ->109.1 
D6 191.0 -> 99.1 
191.0 -> 67.0 

338.9 -> 195.0 
338.9 -> 197.0 

338.9 -> 195.0 
338.9 -> 197.0 
13C9 348.0 -> 
131.2 
348.0 -> 167.0 

272.2 -> 237.2 
272 -> 117 
387 -> 253 

384.9 -> 204.0 
384.9 -> 217.1 
13C6 395.9 -> 
214.1 
397.9 -> 214.1 

163.00 -> 127.00 
181.00 -> 127.00 

172.00 -> 93.00 
253.00 -> 172.00 

304.00 -> 179.00 
304.00 -> 164.00 

185.00 -> 93.00 
185.00 -> 109.00 

241.00 -> 206.00 
195.00 -> 160.00 
241.00 -> 170.00 

241.00 -> 206.00 
195.00 -> 160.00 
241.00 -> 170.00 

274.00 -> 239.00 
386.80 -> 288.80 

344.1 -> 329 
344.1 -> 156 
344.1 -> 171.9 

196.7 -> 168.9 
313.9 -> 257.9 
316.1 -> 260 

163 -> 127 
181 -> 152 

314.0 -> 258.0 
314.0 -> 286.0 

163.0 -> 127.0 
165.0 -> 127.0 

196.9 -> 168.9 
198.9 -> 170.9 
313.8 -> 257.8 
198.9 -> 171.0 
196.9 -> 169.0 

181.0 -> 150.0 
163.0 -> 127.0 
209.0 -> 141.1 
163.0 -> 127.0 
163.0 -> 91.0 

10 

344.1 -> 155.8 
344.1 -> 329.0 
387.9 -> 360.0 

252.8 -> 92.9 
181 -> 152.1 
252.8 -> 172 

151.0 -> 172.0 
172.0 -> 93.0 
253.0 -> 174.0 
180.9 -> 151.9 
252.9 -> 93.0 
250.7 -> 172.0 
181.0 -> 152.1 
252.9 -> 93.0 

137.1 -> 84.1 
199 -> 93 
304.1 -> 179.1 

304.0 -> 179 
199.0 -> 135 

137.1 -> 84.1 
179.1 -> 137.1 
137.1 -> 84.0 
137.1 -> 54.0 
179.1 -> 137.1 

185.0 -> 93.0 
109.0 -> 79.0 

240.6 -> 205.9 
158.9 -> 123 
194.7 -> 125 

241.0 -> 206.0 
239.0 -> 204.0 

240.8 -> 205.9 
264.8 -> 192.9 
276.7 -> 241.9 
194.9 -> 160.0 
236.8 -> 118.9 

158.9 -> 123 
194.7 -> 125 
194.7 -> 159.4 

274 -> 239 
238.7 -> 203.9 
271.7 -> 234.9 

241.0 -> 206.0 
239.0 -> 204.0 

272.0 -> 237.0 
387.0 -> 289.0 

271.8 -> 236.8 
339.8 -> 195.9 
236.8 -> 118.8 
206.9 -> 172.0 
276.7 -> 240.9 

386.8 -> 240.8 
421.8 -> 386.8 
271.9 -> 237.0 
271.9 -> 235.0 
273.8 -> 238.9 

56 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
LAB 
CODE 
1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

Fipronil 

Fipronil sulfone 

Imazalil 

Malaoxon 

Malathion 

Permethrin 

Tebuconazole 

other 

366.8 -> 212.8 
254.9 -> 228.0 
350.8 -> 254.8 

382.8 -> 254.9 
254.9 -> 227.9 
384.8 -> 256.8 

214.9 -> 173.0 
216.8 -> 175.0 
D5 220.0 -> 173.2 
222.0 -> 161.0 
222.0 -> 175.1 

126.9 -> 99.0 
126.9 -> 55.0 
98.9 -> 71.0 

126.9 -> 99.0 
157.8 -> 125.0 
172.9 -> 99.0 

183.1 -> 153.1 
183.1 -> 168.1 
183.1 -> 165.1 

250.0 -> 125.0 
125.0 -> 99.0 
125.0 -> 89.0 

367.0 -> 213.0 
213.0 -> 143.0 

383.0 -> 255.0 
383.0 -> 213.0 

366.9 -> 213.1 
368.9 -> 215.1 
13C6 371.0 -> 
213.1 
373.0 -> 215.1 

127 -> 99 
173 -> 99 

183 -> 168 
183 -> 155 

126.9 -> 99.0 
157.8 -> 125.0 

183.1 -> 168.1 
183.1 -> 153.1 

183 -> 168 
183 -> 153 

250 -> 125 
250 -> 70 

173.2 -> 98.8 
127.1 -> 99.0 
D10 183.2 -> 
99.7 
132.2 -> 99.6 

183.0 -> 153.3 
183.0 -> 168.3 
D5 189.1 -> 
158.5 
188.1 -> 157.5 

250.1 -> 125.0 
252.1 -> 127.0 
D6 256.1 -> 
125.0 
258.0 -> 127.1 

367.00 -> 213.00 
367.00 -> 255.00 

452.00 -> 
383.00 
383.00 -> 255.00 

127.00 -> 99.00 
127.00 -> 109.00 

173.10 -> 99.00 
173.10 -> 127.00 

183.10 -> 165.10 
183.10 -> 168.10 

250.00 -> 153.00 
250.00 -> 163.00 

Triphenylphosphate
325.00 ->169.00 
325.00 -> 231.00 

366.9 -> 254.9 
369.9 -> 214.9 
368.8 -> 214.8 
254.9 -> 228.0 
366.8 -> 212.8 

255.0 -> 228.0 
383.0 -> 255.0 
382.8 -> 254.9 
384.8 -> 256.8 
254.9 -> 227.9 

127.0 -> 99.0 
127.0 -> 109.0 

157. 8-> 125.0 
157.8 -> 47.0 

127.0 -> 99.0 
127.0 -> 109.0 

127.0 -> 99.0 
173.0 -> 99.0 

250 -> 125 
125 -> 89 
125 -> 99 

250.0 -> 125.0 
250.0 -> 153.0 

183.1 -> 165.1 
183.1 -> 153 

163.0 -> 127.0 
165.0 -> 127.0 
183.0 -> 128.0 
183.0 -> 153.0 
183.0 -> 168.0 
164.9 -> 91.1 
162.9 -> 127.0 
182.9 -> 168.1 

57 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Annex  E.  Analytical methods used for characterisation of ERM-BC706 

Table E.3 Details of analytical methods, as given by the laboratories where liquid chromatography was applied for the determination of 
pesticides in wheat flour. 

LABORATORY 
CODE 

Sample 
intake 
 (g) 

Internal Standard 

Extraction 

Clean up 

Stationary phase 
and dimensions 
analytical column 

C18 (100mm, 3 
mm, 3 µm)  

Analytical column   Calibration  

Ionisation 
technique 

Mass 
analyser/detecto
r 

Gemini NX-C18 

ESI 

5 

Imidacloprid-D4 

Quechers, Acetonitril/Water 
(1:1), shaking for 15 min, 
centrifugation 

01 

2  Chlormequat-D4 

5  Glyphosat 13C2 

15N, AMPA 13C15N 

5  Oxfendazole 

02 

5 

Methanol/Water (1:1) 30 min 
Ultrasonication, 15 min 
shaking 
Methanol/Water (1:1) 30 min 
Ultrasonication, 15 min 
shaking 
add 10 ml of water, let stand 
15 min, add 20 ml of 
methanol , mix with ultraturrax 
1 min 
add 10 ml of water, let stand 
15 min, add 20 ml of 
methanol , mix with ultraturrax 
1 min 

salting out, with MgSO4, 
NaCl, Sodiumcitrate buffer, 
centrifugation, 6-ml Aliquot, 
shaking with PSA/MgSO4 
centrifugation, 1ml acidified 
by formic acid 
freezing out overnight 

HILIC (50mm, 2.1 
mm, 2.6 µm) 

Thermo Accucore 
HILIC 

ESI 

freezing out overnight 

C18 (100mm, 3mm,   Gemini NX C18 

centrifugation, filtration 

C18 (100mm, 2.1 
mm, 1.7 µm)  

Acquity BEH C18 
(Waters) 

Procedural 
calibration 

ESI 

centrifugation, filtration 

Styrene 
divinylbenzene 
copolymer (150mm, 
4.6 mm, 3.5 um) 

Shodex RSpak DE
413 

Procedural 
calibration, 
matrix 
matched 

‐

BEH C18 (100mm, 
2.1 mm, 1.7 um) 

Acquity UPLC BEH 
C18 

ESI 

ESI 

1  Glyphosate 13C2 

15N 
AMPA C13 N15 

10 ml of MilliQ Water, 10 ml 
of methanol and 5 ml of 
dichloromethane. Use of 
ultraturrax during 1 min 

centrifugation 20 min at 5 
°C, glyphosate and AMPA are 
derivatized with FMOC-
chloride before injection 

5 

Water/acetonitrile, 10 + 10 mL  QuEChERS - PSA/ODS  150 

mg/150 mg 

Triple 
quadrupole 

Triple 
quadrupole 

Triple 
quadrupole 

Triple 
quadrupole 

Triple 
quadrupole 

Triple 
quadrupole 

BEH C18 (150mm, 
2.1 mm, 1.7 um) 

Acquity UPLC BEH 
C18 

Calibration 
curve 

ESI 

Triple 
quadrupole 

03 

glyphosate 2-13C 
15N 

10 mL Water + 10 mL MeOH 
(Formic Acid 1%) + 100 µL 
Formic Acid 

Freeze out (-80°C) 30'; 
ultracentrifuge 15000 RCF 
5' (4°C) - Vivaspin (6 mL; 
5KDa) 

Proprietary 
(100mm, 2.1 mm, 
5um) 

Hypercarb 

ESI 

QTOF 

58 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
LABORATORY 
CODE 

Sample 
intake 
 (g) 

Internal Standard 

Extraction 

Clean up 

Analytical column   Calibration  

Ionisation 
technique 

Mass 
analyser/detecto
r 

04 

05 

06 

07 

Stationary phase 
and dimensions 
analytical column 

endcapped C18 
(octadeylsilane) 
50mm, 2.1 mm, 
1.8µm 

Agilent Zorbax 
EclipsePlus C18 
RRHD 

Matrix 
matched 

5  D4-Carbendazim, 
D6-Pirimicarb, D6-
Pirimiphos-methyl, 
Triphenylphosphate 

Citrate buffered Quechers 
extraction with acetonitrile 

no cleanup 

1  D9-Chlormequat 

chloride 

Extraction with acidified 
methanol (1% formic acid) 

freezing, dilution of extract 
with acetonitrile 

(150mm, 2.1mm, 
5µm) 

SIELC Obelisc R,  

2  1,2-13C2-15N 
Glyphosate 

Extraction with 
methanol/water followed by 
SPE and derivatization using 
FMOC-Cl 

SPE (cation exchanger and 
anion exchanger) 

C18 (100mm, 4.6 
mm, 2.7 um) 

Agilent Poroshell 
120 EC-C18 2.7 
µm 

ESI 

ESI 

ESI 

Triple 
quadrupole 

Triple 
quadrupole 

Triple 
quadrupole 

chlorpyrifos-D10 
Diazinon-D10  
13C4-Fipronil 
Imazalil-D5 
Imidacloprid-D4 
Linuron-D6 
Malathion-D10 
Malaoxon-D7 
Tebuconazole-D6 
Thiabendazole-D6 
Triphenylphosphate 

chlormequat 1,1,2,2 
D4 
glyphosate 1,2-
13C2 15N 

1 

5 

5 

5 

Citrate buffered extraction 
with acetonitrile 

Supelco C18 SPE and 
Supelco PSA SPE  

C18 (100 mm, 2.1 
mm, 1.7 µm) 

Waters Acquity 
UPLC BEH C18 

Response 
factor 

ESI 

Triple 
quadrupole 

4mL of acetonitrile extract 
with 1,0g MgSO4/0,6g PSA / 
0,4g C18. Shake and 
centrifuge 4'/4000 rpm. 

C18 Selectivity 
(100mm, 2.1 mm, 
1.9 um) 

Thermo Hypersil 
GOLD 

Calibration 
curve 

ESI 

Triple 
quadrupole 

(100 mm, 2.1 mm, 
5 um) 

Hypercarb™ 

Calibration 
curve 

ESI 

Triple 
quadrupole 

8 ml extract, 900 mg PSA 
and 900 mg MgSO4, shaken 
30 seconds and centrifuged 
five min at 4500 rpm 

(100mm, 2.1 mm, 
1.7 um) 

Accuity UPLC BEH 
C18  reversed-
phase column 

Calibration 
curve 

ESI 

Triple 
quadrupole 

QuEChERS: 5g sample/5 
H2O/10 mL Acetonitrile 1% 
Acetic Acid plus 1ppm Tphp. 1h 
freezing. 5 g MgSO4/AcONa 
(4:1). Shake 1' and centrifuge 
4'/4000 rpm 
QuPPe-PO-Method (Version 
11.1; 17-03-2021) for cereals. 
Section 5.2 

Ceramic homogenizer, 10 mL 
water/10 mL acetonitrile. 
mechanically shaken 5 min. 4 
g MgSO4, 1 g NaCl, 1 g Na3 
citrate dihydrate and 0.5 g 
Na2H cirate sesquihydrate, 
shaken 1 min, centrifuged 10 
min at 4500 rpm. 8 ml frozen 
out. Centrifuged 5 °C, 10 min 
4500 rpm. 

59 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
LABORATORY 
CODE 

Sample 
intake 
 (g) 

Internal Standard 

Extraction 

Clean up 

10 

Triphenylphosphate 
Atrazine-d5 

QuEChERS 

None 

08 

2.5  Mepiquat-d16 

QuPPE-Method 

C18 + Acetonitrile 

Stationary phase 
and dimensions 
analytical column 

C18 (100mm, 
2.1mm, 1.8 um) 

(100mm, 2.1mm, 
2.7 um) 

InfinityLab 
Poroshell 120 EC-
C18 
Poroshell 120 
HILIC-Z 

Matrix 
matched 

Matrix 
matched 

Analytical column   Calibration  

Ionisation 
technique 

Mass 
analyser/detecto
r 

ESI 

ESI 

ESI 

Triple 
quadrupole 

Triple 
quadrupole 

Triple 
quadrupole 

2  Glyphosate C13N15 
AMPA C13N15 

FMOC Derivatization 

PassTrough Bond Elut 
Cartridge 

(100mm, 2.1mm, 
2.5um) 

XSELECT HSS T3 

Matrix 
matched 

09 

10 

2 

2 

10 mL of water, automatic 
shaker 10 min, 10 mL 
acetonitrile and QuEChERS 
citrate salts, automatic shaker 
for 10 min 
10 mL of water, automatic 
shaker for 10 min, add 10 mL 
of methanol, automatic shaker 
for 10 min 

Centrifugation, freezing-out, 
d-SPE (PSA) clean-up, 
ultrafiltration through PVDF 
0,22 µm filters prior analysis 

Reversed phase 
(50mm, 3mm, 
1.7um) 

Centrifugation, ultrafiltration 
through PVDF 0,22 µm 
filters prior analysis 

Reversed phase 
(150mm, 2.1mm, 
5um) 

Kinetex C18  

Calibration 
curve 

ESI 

Triple 
quadrupole 

SCIELC Obelisc R 

Calibration 
curve 

ESI 

Triple 
quadrupole 

2  Glyphosate 13C2 

15N 
AMPA 13C 15N 

10 mL of water, automatic 
shaker for 10 min, add 10 mL 
of methanol, automatic shaker 
for 10 min 

Centrifugation, ultrafiltration 
through PVDF 0,22 µm 
filters prior analysis 

Reversed phase 
(100mm x 2,1 mm 
5 µm) 

Hypercarb  

Calibration 
curve 

ESI 

Triple 
quadrupole 

5 

10 mL water, extraction with 
10 mL of acetonitrile, manual 
shaking 3 min. 

5  Chlormequat 

chloride 1,1,2,2-D4 

5  Glyphosate-13C2, 

15N 

solvent: water + 1% formic 
acid in methanol, extraction: 
15 minutes in shaker 

solvent: water + 1% formic 
acid in methanol, extraction: 
15 minutes in shaker 

Outsalting with sodium 
chloride - sodium citrate - 
sodium hydrogen citrate and 
magnesium sulphate, dSPE 
puri-fication with PSA, freeze 
EDTA, formic acid and 
acetonitrile,precipitation, 
freezing out, Vivaspin 
filtration 
EDTA, formic acid and 
acetonitrile precipitation, 
freezing out, Vivaspin 
filtration 

60 

C18 (100mm, 
2.1mm, 1.7um) 

Waters: Acquity 
UPLC BEH 

bracketing 

ESI 

Triple 
quadrupole 

BEH HILIC (100mm, 
2.1 mm, 1.7um) 

Waters: Acquity 
UPLC BEH HILIC 

bracketing 

ESI 

DEA (diethylamine) 
(100mm, 2.1mm, 
5um) 

Waters: Anionic 
Polar Pesticide 

Bracketing 

ESI 

Triple 
quadrupole 

Triple 
quadrupole 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Table E.4: m/z transitions used for quantitative (in bold) and qualitative purposes for the different target compounds (liquid 
chromatography) 

LAB 
CODE 
1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

Azoxystrobin  

Chlorpyrifos 

Deltamethrin 

Diazinon 

Dichlorvos 

Fipronil 

Fipronil sulfone 

Imazalil 

Imidacloprid 

Linuron 

404 -> 372 
404 -> 329 

404 –> 372 
404 -> 344 

404 -> 372 
404 -> 344 

404->329 
404->344 
404->172 
D4 408->333 

404.1 -> 372.1 
211.0 -> 136.0 

404 -> 344 
404 -> 372 

221 -> 109 
221 -> 127 

256 -> 209 
256 -> 175 

249 -> 160 
249 -> 182 

221 ->109 
221 -> 95 

435 ->  330 
435 -> 250 

451 -> 415 
453 -> 415 

297 -> 159 
297 -> 69 

256 -> 175 
256 -> 209 

249 -> 160 
249 -> 182 

523 –> 281 
523 -> 506 

305 –> 169 
305 -> 153 

221 –> 109 
221 -> 127 

435 –> 330 
437 -> 332 

451 –> 415 
451 -> 282 

297 –> 159 
297 -> 201 

256 –> 175 
256 -> 209 

249 –> 160 
249 -> 182 

305.1 -> 169 
305.1 -> 96.9 

221 -> 109 
221 -> 79 

435 -> 330 
435 -> 250 

451 -> 415 
451 -> 282 

297 -> 201 
297 -> 159 

256.1 -> 209 
256.1 -> 175.1 

248.9 -> 181.9 
248.9 -> 160.1 

350 -> 198 
352 -> 200 
350 -> 125 
D10    360 -> 
131 

305 -> 169  
 305 -> 153  
 305 -> 97 
D10  315 -> 170 

435 -> 330 
435 -> 250 
435 -> 183 
13C4 439 -> 334 

435.22 -> 330.20 
435.22 -> 250.10 

451 -> 415 
451 -> 282 
453 -> 417 

297 -> 159 
297 -> 69 
299 -> 161 
D5  302 -> 159 

256 -> 209 
256 -> 175 
256 -> 84 
D4  260 -> 213 

249 -> 160 
249 -> 182 
249 -> 133 
D6  257 -> 162 

297.10 -> 176.00 
299.10 -> 41.10 

256.20 -> 209.10 
256.20 -> 175.15 

249.10 -> 160.00 
249.10 -> 182.15 

297 -> 159 
297 -> 201 

256 -> 175 
256 -> 209 

249 -> 160 
249 -> 182 

435.0 -> 330.0 
435.0 -> 250.0 

451.0 -> 415.0 
451.0 -> 282.0 

297.1 -> 159.0 
297.1 -> 201.0 

256.0 -> 208.9 
256.0 -> 175.0 

249.0 -> 160.1 
249.0 -> 182.3 

221 -> 109 
223 -> 109 

221 -> 109 
221 -> 79 

397 -> 159 
297 -> 201 

297 -> 159 
297 -> 69 

256 -> 175 
256 -> 209 

249 -> 160 
249 -> 182 

256.1 -> 209 
256.1 -> 174.9 

249 -> 159.9 
249 -> 181.9 

61 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
LAB 
CODE 

Malaozon 

Malathion 

Permethrin 

Tebuconazole 

Thiabendazole 

Other (as 
internal 
standard) 

Chlormequat 

Glyphosate 

AMPA 

1 

2 

3 

4 

5 

6 

7 

8 

9 

315 -> 127 
315 ->  99 

308 -> 70 
310 -> 70 

202 -> 175 
202 -> 131 

oxfendazole 
316 -> 159 

122 -> 58 
124 -> 58 

202 -> 175 
202 -> 131 

122 -> 58.2 
124 -> 58.2 

315 –> 127 
315 -> 99 

331 –> 127 
331 -> 285 

308 –> 70 
308 -> 125 

202 –> 131 
202 -> 175 

315 -> 127 
315 -> 99 

331 -> 285 
331 -> 127 

202 -> 175 
202 -> 131 

122 -> 58.1 
122 -> 63 
D9  131 -> 66.1 

315 -> 99 
315 -> 127 
315 -> 143 
D6 322- > 100 

331 -> 127 
331 -> 285 
331 -> 79 
D10  341 -> 132 

308 -> 70 
310 -> 70 
308 -> 125 
D6 314 -> 72 

202- > 175 
202 -> 131 
202 -> 65 
D6 208 -> 136 
202.00 -> 175.00 
202.00 -> 66.10 

315 -> 99 
315 -> 127 

331 -> 99 
331 -> 127 

202 -> 131 
202 -> 175 

202.0 -> 175.0 
202.0 -> 131.0 

308 -> 70 
308 -> 125 

202 -> 131 
202 -> 175 

10 

315 -> 127 
315 -> 98.9 

331.126 -> 
126.993 
331.126 -> 78.902 

408.3 -> 183 
408.24 -> 
355.126 

308.2 -> 70.1 
308.2 -> 124.9 

202 -> 174.9 
202 -> 130.9 

Triphenylphosp
hate 
325.00 -> 
169.00 
325.00 -> 
231.00 

122.10 -> 58.15 
122.10 -> 42.05 
124.20 -> 58.15 
D4 126.00 -> 58.20 
126.00 -> 67.05 
126.00 -> 59.20 

122.0 -> 58.0 
122.0 -> 63.0 
124.0 -> 58.0 
D16 130.0 -> 112.0 
122 -> 58 
124 -> 58 

122 -> 58 
122 -> 59 
122 -> 63 
D4 126 -> 59 
126 -> 58 

62 

212 -> 155.7 
212 -> 111.8 
N15 214 -> 
113.8 
334.05 -> 179.1 
334.05 -> 112.1 
C13N15  
336.2 -> 179.1 

110.0 - 62.9641 
110.0 - 78.9591 

351.1 -> 179 
351.1 -> 156 
351.1 -> 112 

110.20 -> 78.95 
110.20 -> 62.90 
110.00 -> 81.00 

332 -> 110 
332 -> 136 
13C.15N 
334 -> 112 
110 -> 63 
110 -> 79 
13C 15N 
112 -> 63 

269.9 -> 87.9 
269.9 -> 195.7 
N15 272.9 -> 90.9 
272.9 -> 125.9 
391.95 -> 88.0 
391.95 -> 179.1 
C13N15  
395.1 > 91.1 

168.1 -> 62.9641 
168.1 -> 149.9962 
13C15N  
170.0 -> 62.9641 
392.1 -> 88 
392.1 -> 170 
392.1 -> 179 
13C15N 395.1 -> 91 
395.1 -> 173 
395.1 -> 179 

169.90 -> 88.10 
169.90 -> 42.10 
169.90 -> 60.10 
13C2 15N 173.00 -> 
91.05 
173.00 -> 43.95 
173.00 -> 62.15 

390 -> 168 
390 -> 150 
13C.15N 
392 -> 170 
168 -> 63 
168 -> 150 
13C2 15N 
171 -> 63 
168 -> 150 
167.9 -> 62.9 
3C2. 15N  171 ->126 
171 -> 63 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Annex F: Results of the characterisation measurements 

Table F.1. Mass fractions of AMPA in wheat as reported by participant laboratories.  

LABORATORY 
CODE 

L01-LC-MS/MS 

L02-LC-MS/MS 

L03-LC-MS/MS 

L04-LC-MS/MS 

L08-LC-MS/MS 

L09-LC-MS/MS 

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

Expanded 
uncertainty 
[mg/kg] 

<0,05 

<0,05 

<0,05 

<0,05 

<0,05 

0.0649 

0.0608 

0.0663 

0.0713 

0.0776 

<0.1 

<0.1 

<0.1 

<0.1 

<0.1 

<0,05 

0.077 

<0.1 

0.070 

0.013 

0.0795 

0.0886 

0.102 

0.104 

0.0915 

0.088 

0.092 

0.028 

0.1224 

0.138 

0.1149 

0.0911 

0.1089 

0.0948 

0.0595 

0.0593 

0.057 

0.0659 

0.0625 

0.0602 

0.112 

0.061 

0.056 

0.009 

AMPA

0.20

0.15

0.10

t
a
e
h
w
g
k
/
g
m

0.05

0.00

L02

L04

L08

L09

Laboratory code

Figure F.1. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM

63 

 
 
 
 
 
 
 
 
 
 
 
 
 
Table F.2. Mass fractions of azoxystrobin in wheat as reported by participant laboratories.  

LABORATORY 
CODE 

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

L01-GC-MS/MS 

0.077 

0.081 

L02-LC-MS/MS 

0.0958 

0.0936 

L03-LC-MS/MS 

0.092 

0.094 

0.072 

0.108 

0.093 

0.077 

0.0898 

0.087 

0.077 

0.110 

0.087 

0.0700 

0.0656 

0.0667 

0.0734 

0.0734 

0.077 

0.116 

0.089 

0.069 

0.077 

0.102 

0.070 

0.090 

0.045 

Expanded 
uncertainty 
[mg/kg] 
0.016 

0.051 

0.028 

0.011 

0.007 

0.012 

0.0743 

0.0752 

0.0763 

0.0764 

0.079 

0.0757 

0.076 

0.0467 

0.0504 

0.0506 

0.0535 

0.0563 

0.0538 

0.065 

0.060 

0.064 

0.057 

0.062 

0.060 

0.052 

0.062 

0.0772 

0.0805 

0.0722 

0.0771 

0.0771 

0.0774 

0.079 

0.039 

0.0652 

0.0718 

0.0656 

0.0584 

0.0652 

0.0618 

0.0718 

0.0727 

0.0750 

0.0765 

0.0742 

0.0762 

0.065 

0.074 

0.010 

0.037 

azoxystrobin

L04-LC-MS/MS 

L05-GC-MS/MS 

L06-GC-MS/MS 

L07-GC-MS/MS 

L08-LC-MS/MS 

L09-LC-MS/MS 

L10-GC-MS/MS 

t
a
e
h
w
g
k
/
g
m

0.20

0.15

0.10

0.05

0.00

L01

L02

L03

L04

L05

L06

L07

L08

L09

L10

Laboratory code

Figure F.2. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM

64 

 
 
 
 
 
 
 
Table F.3. Mass fractions of chlormequat in wheat as reported by participant laboratories.  

LABORATORY 
CODE 

L01-LC-MS/MS 

L02-LC-MS/MS 

L04-GC-MS/MS 

L08-LC-MS/MS 

L09-LC-MS/MS 

L10-LC-MS/MS 

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

2.436 

2.499 

2.276 

0.989 

1.966 

2.02 

2.343 

2.296 

2.302 

0.982 

2.022 

1.98 

2.364 

2.595 

2.272 

1.036 

1.886 

2.04 

2.402 

2.349 

2.410 

1.383 

1.897 

2.06 

2.465 

2.609 

2.244 

1.388 

1.943 

2.00 

2.467 

2.376 

2.365 

1.491 

1.943 

2.06 

2.41 

2.45 

2.31 

1.21 

1.94 

2.03 

Expanded 
uncertainty 
[mg/kg] 
0.45 

1.23 

0.46 

0.61 

0.14 

1.01 

chlormequat

t
a
e
h
w
g
k
/
g
m

5.0

4.0

3.0

2.0

1.0

0.0

L01

L02

L04

L08

L09

L10

Laboratory code

Figure F.3. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM  

65 

 
 
 
 
 
 
 
 
 
 
 
 
Table F.4. Mass fractions of chlorpyrifos in wheat as reported by participant laboratories.  

LABORATORY 
CODE 

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

L01-GC-MS/MS 

2.545 

2.472 

Expanded 
uncertainty 
[mg/kg] 
0.37 

1.48 

1.36 

0.82 

0.15 

0.23 

0.35 

0.37 

1.13 

0.87 

0.95 

2.49 

2.96 

2.72 

2.04 

2.74 

2.52 

2.24 

2.08 

2.25 

2.81 

1.90 

2.93 

2.62 

2.014 

2.75 

2.51 

2.65 

2.63 

1.95 

2.72 

2.47 

2.61 

2.74 

2.68 

2.033 

2.77 

2.45 

2.284 

3.14 

2.71 

2.14 

2.78 

2.61 

2.088 

2.000 

2.298 

2.225 

2.21 

2.03 

2.09 

1.99 

2.47 

3.06 

2.84 

2.541 

3.28 

2.83 

1.993 

2.129 

2.80 

2.50 

2.33 

2.09 

2.64 

2.56 

2.501 

2.07 

2.2613 

2.2271 

2.2441 

2.2819 

2.2613 

2.243 

2.78 

1.82 

2.67 

1.85 

3.11 

1.82 

2.64 

1.89 

2.98 

2.08 

2.68 

1.94 

chlorpyrifos

L02-GC-MS/MS 

L03-GC-MS/MS 

L04-GC-MS/MS 

L05a-GC-MS/MS 

L05b-LC-MS/MS 

L06-GC-MS/MS 

L07-GC-MS/MS 

L08-GC-MS/MS 

L09-GC-MS/MS 

L10-GC-MS/MS 

5.0

4.0

t
a
e
h
w
g
k
/
g
m

3.0

2.0

1.0

0.0

L01

L02

L03

L04

L05a

L05b

L06

L07

L08

L09

L10

Laboratory code

Figure F.4. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM  

66 

 
 
 
 
 
 
 
 
 
 
 
Table F.5. Mass fractions of cypermethrin in wheat as reported by participant laboratories.  

LABORATORY 
CODE 

L01-GC-MS/MS 

L02-GC-MS/MS 

L03-GC-MS/MS 

L04-GC-MS/MS 

L05-GC-MS/MS 

L07-GC-MS/MS 

L08-GC-MS/MS 

L09-GC-MS/MS 

L10-GC-MS/MS 

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

3.876 

3.953 

3.931 

3.952 

4.264 

4.410 

3.42 

4.63 

3.16 

4.69 

3.65 

4.75 

4.26 

4.71 

3.63 

5.02 

4.32 

4.88 

3.653 

3.652 

3.650 

4.076 

4.060 

3.773 

3.99 

3.84 

4.05 

3.46 

4.07 

3.45 

3.94 

3.41 

4.24 

3.43 

4.17 

3.33 

2.5687 

2.5931 

3.4199 

2.6738 

3.4008 

3.4075 

3.59 

2.57 

3.52 

2.24 

3.51 

2.61 

2.84 

2.64 

3.09 

2.91 

3.50 

2.74 

4.06 

3.74 

4.78 

3.81 

4.08 

3.49 

3.01 

3.34 

2.62 

Expanded 
uncertainty 
[mg/kg] 
1.12 

1.87 

2.39 

1.52 

0.21 

0.70 

1.51 

0.87 

1.31 

cypermethrin

t
a
e
h
w
g
k
/
g
m

8.0

6.0

4.0

2.0

0.0

L01

L02

L03

L04

L05

L07

L08

L09

L10

Laboratory code

Figure F.5. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM  

67 

 
 
 
 
 
 
 
 
 
Table F.6. Mass fractions of deltamethrin in wheat as reported by participant laboratories.  

LABORATORY 
CODE 

L01-GC-MS/MS 

L02-GC-MS/MS 

L03-GC-MS/MS 

L04-GC-MS/MS 

L05-GC-MS/MS 

L07-GC-MS/MS 

L08-GC-MS/MS 

L09-GC-MS/MS 

L10-GC-MS/MS 

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

3.899 

3.918 

4.026 

3.772 

4.191 

4.217 

2.77 

4.18 

2.97 

4.23 

3.02 

4.46 

3.7 

3.88 

2.79 

4.01 

3.29 

4.04 

3.333 

3.500 

3.577 

3.842 

3.434 

3.383 

5.71 

4.01 

5.67 

3.61 

5.64 

3.65 

5.30 

3.63 

5.88 

3.64 

6.21 

3.55 

3.1195 

3.1148 

2.2206 

3.2259 

2.3376 

2.3379 

4.22 

2.68 

4.04 

2.13 

4.33 

3.18 

5.12 

2.80 

4.53 

3.24 

4.04 

3.08 

4.00 

3.09 

4.13 

3.51 

5.74 

3.68 

2.73 

4.38 

2.85 

Expanded 
uncertainty 
[mg/kg] 
1.36 

1.55 

2.07 

1.40 

0.51 

1.25 

1.36 

1.05 

1.43 

deltamethrin

t
a
e
h
w
g
k
/
g
m

8.0

6.0

4.0

2.0

0.0

L01

L02

L03

L04

L05

L07

L08

L09

L10

Laboratory code

Figure F.6. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM  

68 

 
 
 
 
 
 
 
 
 
Table F.7. Mass fractions of diazinon in wheat as reported by participant laboratories.  

LABORATORY 
CODE 

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

Expanded 
uncertainty 
[mg/kg] 
0.093 

0.459 

0.441 

0.456 

0.42 

0.471 

0.438 

0.413 

0.32 

0.430 

0.301 

0.300 

0.41 

0.44 

0.447 

0.445 

0.389 

0.323 

0.443 

0.287 

0.274 

0.468 

0.416 

0.45 

0.448 

0.442 

0.423 

0.333 

0.443 

0.290 

0.288 

0.40 

0.469 

0.419 

0.443 

0.317 

0.431 

0.238 

0.273 

0.44 

0.45 

0.457 

0.425 

0.426 

0.335 

0.442 

0.258 

0.289 

0.44 

0.467 

0.411 

0.411 

0.326 

0.423 

0.276 

0.284 

0.3483 

0.3496 

0.3363 

0.3566 

0.3223 

0.3238 

0.411 

0.352 

0.393 

0.351 

0.443 

0.347 

0.387 

0.363 

0.423 

0.403 

0.397 

0.369 

diazinon 

0.435 

0.217 

0.460 

0.430 

0.418 

0.326 

0.230 

0.215 

0.167 

0.015 

0.435 

0.033 

0.275 

0.284 

0.339 

0.409 

0.088 

0.085 

0.170 

0.074 

0.364 

0.182 

L01-GC-MS/MS 

L02-GC-MS/MS 

L03a-GC-MS/MS 

L03b-LC-MS/MS 

L04-LC-MS/MS 

L05a-GC-MS/MS 

L05b-LC-MS/MS 

L06-GC-MS/MS 

L07-GC-MS/MS 

L08-GC-MS/MS 

L09-GC-MS/MS 

L10-GC-MS/MS 

t
a
e
h
w
g
k
/
g
m

0.8

0.6

0.4

0.2

0.0

L01

L02

L03a

L03b

L04

L05a

L05b

L06

L07

L08

L09

L10

Laboratory code

Figure F.7. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM  

69 

 
 
 
 
 
 
 
Table F.8 Mass fractions of dichlorvos in wheat as reported by participant laboratories.  

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

Expanded 
uncertainty 
[mg/kg] 
0.066 

0.254 

0.172 

0.086 

0.409 

0.403 

0.176 

0.327 

0.205 

0.029 

0.088 

0.065 

0.249 

0.124 

0.243 

0.182 

0.392 

0.400 

0.161 

0.322 

0.247 

0.251 

0.147 

0.385 

0.414 

0.264 

0.17 

0.43 

0.394 

0.1865 

0.1851 

0.263 

0.164 

0.434 

0.403 

0.243 

0.177 

0.424 

0.398 

0.248 

0.240 

0.356 

0.257 

0.332 

0.254 

0.367 

0.246 

dichlorvos 

LABORATORY 
CODE 

L01-LC-MS/MS 

L02-LC-MS/MS 

L03-LC-MS/MS 

L05-GC-MS/MS 

0.260 

0.192 

0.389 

0.407 

L08-GC-MS/MS 

0.1721 

L09-LC-MS/MS 

L10-LC-MS/MS 

0.341 

0.249 

t
a
e
h
w
g
k
/
g
m

0.6

0.4

0.2

0.0

L01

L02

L03

L05

L08

L09

L10

Laboratory code

Figure F.8. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM  

70 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Table F.9. Mass fractions of α-endosulfan in wheat as reported by participant laboratories.  

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

0.0862 

0.0927 

0.0895 

0.086 

0.0868 

0.0878 

0.11 

0.129 

0.108 

0.09 

0.125 

0.106 

0.08 

0.128 

0.106 

0.07 

0.117 

0.110 

0.08 

0.112 

0.112 

0.11 

0.114 

0.114 

0.1005 

0.0892 

0.0985 

0.0962 

0.1046 

0.0935 

0.1055 

0.0967 

0.1024 

0.1016 

0.1075 

0.1008 

0.0580 

0.0533 

0.0606 

0.0576 

Expanded 
uncertainty 
[mg/kg] 
0.016 

0.045 

0.088 

0.089 

0.121 

0.060 

0.109 

0.097 

0.102 

0.057 

0.044 

0.016 

0.041 

0.029 

0.0970 

0.0916 

0.1104 

0.0948 

0.1061 

0.0842 

0.097 

0.037 

0.0802 

0.0741 

0.0779 

0.0784 

0.0729 

0.0762 

0.077 

0.038 

α-endosulfan 

LABORATORY 
CODE 

L01-GC-MS/MS 

L02-GC-MS/MS 

L03-GC-MS/MS 

L04-GC-MS/MS 

L05-GC-MS/MS 

L07-GC-MS/MS 

L08-GC-MS/MS 

L09-GC-MS/MS 

L10-GC-MS/MS 

t
a
e
h
w
g
k
/
g
m

0.20

0.15

0.10

0.05

0.00

L01

L02

L03

L04

L05

L07

L08

L09

L10

Laboratory code

Figure F.9. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM  

71 

 
 
 
 
 
 
 
 
 
 
 
 
 
Table F.10. Mass fractions of β-endosulfan in wheat as reported by participant laboratories.  

Expanded 
uncertainty 
[mg/kg] 
0.035 

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

0.236 

0.244 

0.244 

0.237 

0.40 

0.338 

0.283 

0.277 

0.264 

0.36 

0.318 

0.293 

0.280 

0.246 

0.32 

0.322 

0.287 

0.270 

0.256 

0.36 

0.295 

0.307 

0.263 

0.237 

0.2184 

0.2283 

0.2352 

0.2291 

0.25 

0.32 

0.299 

0.307 

0.282 

0.261 

0.256 

0.244 

0.34 

0.299 

0.293 

0.276 

0.247 

0.349 

0.175 

0.312 

0.295 

0.275 

0.252 

0.156 

0.118 

0.030 

0.091 

0.228 

0.114 

0.278 

0.204 

0.297 

0.213 

0.322 

0.226 

0.272 

0.217 

0.311 

0.221 

0.272 

0.228 

0.292 

0.218 

0.079 

0.109 

β-endosulfan 

LABORATORY 
CODE 

L01-GC-MS/MS 

L02-GC-MS/MS 

L03-GC-MS/MS 

L04-GC-MS/MS 

L05-GC-MS/MS 

L07-GC-MS/MS 

L08-GC-MS/MS 

L09-GC-MS/MS 

L10-GC-MS/MS 

t
a
e
h
w
g
k
/
g
m

0.6

0.5

0.4

0.3

0.2

0.1

0.0

L01

L02

L03

L04

L05
Laboratory code

L07

L08

L09

L10

Figure F.10. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM  

72 

 
 
 
 
 
 
 
 
 
 
 
 
 
Table F.11. Mass fractions of endosulfan sulfate in wheat as reported by participant laboratories.  

LABORATORY 
CODE 

L01-GC-MS/MS 

L02-GC-MS/MS 

L03-GC-MS/MS 

L04-GC-MS/MS 

L05-GC-MS/MS 

L07-GC-MS/MS 

L08-GC-MS/MS 

L09-GC-MS/MS 

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

0.316 

0.282 

0.484 

0.376 

0.432 

0.3 

0.312 

0.251 

0.466 

0.387 

0.430 

0.278 

0.326 

0.340 

0.463 

0.373 

0.420 

0.261 

0.315 

0.319 

0.462 

0.368 

0.433 

0.266 

0.2569 

0.2626 

0.2558 

0.2470 

0.338 

0.230 

0.474 

0.385 

0.427 

0.261 

0.358 

0.362 

0.458 

0.345 

0.413 

0.25 

Expanded 
uncertainty 
[mg/kg] 
0.058 

0.149 

0.327 

0.297 

0.468 

0.234 

0.372 

0.426 

0.269 

0.256 

0.149 

0.055 

0.097 

0.128 

0.427 

0.414 

0.482 

0.415 

0.462 

0.401 

0.433 

0.156 

Results not used for value assignment 

L10-GC-MS/MS 

0.131 

0.145 

0.234 

0.163 

0.216 

0.190 

0.180 

0.040 

endosulfan sulfate

t
a
e
h
w
g
k
/
g
m

0.8

0.6

0.4

0.2

0.0

L01

L02

L03

L04

L05

L07

L08

L09

Laboratory code

Figure F.11. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM  

73 

 
 
 
 
 
 
 
 
 
 
 
Table F.12. Mass fractions of the sum of α- β endosulfan and endosulfan sulfate expressed as 
endosulfan in wheat calculated based on the individual mass fractions reported by participant 
laboratories. The expanded uncertainty is estimated as the combined expanded uncertainty. 

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

0.626 

0.778 

0.933 

0.753 

0.793 

0.658 

0.524 

0.786 

0.638 

0.686 

0.891 

0.771 

0.783 

0.610 

0.534 

0.786 

0.648 

0.724 

0.895 

0.752 

0.772 

0.609 

0.542 

0.896 

0.626 

0.739 

0.857 

0.771 

0.776 

0.595 

0.524 

0.765 

0.661 

0.625 

0.867 

0.789 

0.797 

0.620 

0.688 

0.797 

0.854 

0.739 

0.766 

0.589 

Expanded 
uncertainty 
[mg/kg] 
0.070 

0.648 

0.725 

0.234 

0.883 

0.763 

0.781 

0.613 

0.288 

0.195 

0.065 

0.139 

0.531 

0.174 

0.862 

0.742 

0.806 

0.179 

sum endosulfan + endosulfan sulfate 

LABORATORY 
CODE 

L01-GC-MS/MS 

L02-GC-MS/MS 

L03-GC-MS/MS 

L04-GC-MS/MS 

L05-GC-MS/MS 

L07-GC-MS/MS 

L08-GC-MS/MS 

L09-GC-MS/MS 

1.5

t
a
e
h
w
g
k
/
g
m

1.0

0.5

0.0

L01

L02

L03

L04

L05

L07

L08

L09

Laboratory code

Figure F.12. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM  

74 

 
 
 
 
 
 
 
 
 
 
 
 
Table F.13. Mass fractions of fipronil in wheat as reported by participant laboratories.  

LABORATORY 
CODE 

L01-GC-MS/MS 

L02-LC-MS/MS 

L03a-GC-MS/MS 

L03b-LC-MS/MS 

L04-LC-MS/MS 

L05a-LC-MS/MS 

L05b-GC-MS/MS 

L07-LC-MS/MS 

L08-LC-MS/MS 

L09-GC-MS/MS 

L10-GC-MS/MS 

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

0.353 

0.425 

0.482 

0.411 

0.343 

0.437 

0.448 

0.455 

0.293 

0.443 

0.422 

0.338 

0.398 

0.462 

0.473 

0.353 

0.438 

0.461 

0.422 

0.373 

0.485 

0.462 

0.407 

0.383 

0.445 

0.457 

0.312 

0.332 

0.406 

0.456 

0.418 

0.376 

0.433 

0.445 

0.428 

0.398 

0.529 

0.455 

0.421 

0.41 

0.444 

0.456 

0.397 

0.400 

0.519 

0.453 

0.415 

0.403 

0.441 

0.452 

0.45 

0.3235 

0.3441 

0.3032 

0.3249 

0.3095 

0.417 

0.409 

0.482 

0.42 

0.411 

0.438 

0.468 

0.486 

0.432 

0.458 

0.366 

0.460 

0.462 

0.424 

0.378 

0.440 

0.453 

0.411 

0.316 

0.442 

0.439 

Expanded 
uncertainty 
[mg/kg] 
0.072 

0.230 

0.231 

0.212 

0.151 

0.018 

0.012 

0.140 

0.158 

0.168 

0.219 

fipronil 

t
a
e
h
w
g
k
/
g
m

0.8

0.6

0.4

0.2

0.0

L01

L02

L03a

L03b

L04

L05a

L05b

L07

L08

L09

L10

Laboratory code

Figure F.13. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM  

75 

 
 
 
 
 
 
 
 
 
Table F.14. Mass fractions of fipronil sulfone in wheat as reported by participant laboratories.  

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

LABORATORY 
CODE 

L01-GC-MS/MS 

L02-LC-MS/MS 

L03a-GC-MS/MS 

L03b-LC-MS/MS 

L04-LC-MS/MS 

L07-LC-MS/MS 

0.414 

0.598 

0.69 

0.627 

0.557 

0.698 

0.48 

0.575 

0.662 

0.629 

0.536 

0.572 

0.477 

0.665 

0.659 

0.628 

0.612 

0.708 

0.419 

0.529 

0.655 

0.606 

0.586 

0.585 

L08-LC-MS/MS 

0.4959 

0.5104 

0.5226 

0.4969 

L09-GC-MS/MS 

L10-GC-MS/MS 

0.712 

0.547 

0.692 

0.546 

0.823 

0.563 

0.66 

0.562 

0.461 

0.707 

0.653 

0.610 

0.626 

0.551 

0.512 

0.752 

0.620 

0.455 

0.670 

0.658 

0.591 

0.600 

0.554 

0.4916 

0.675 

0.585 

0.451 

0.624 

0.663 

0.615 

0.586 

0.611 

0.505 

0.719 

0.571 

Expanded 
uncertainty 
[mg/kg] 
0.071 

0.312 

0.331 

0.308 

0.234 

0.147 

0.252 

0.144 

0.285 

fipronil sulfone 

t
a
e
h
w
g
k
/
g
m

1.3

1.0

0.8

0.5

0.3

0.0

L01

L02

L03a

L03b

L04

L07

L08

L09

L10

Laboratory code

Figure F.14. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM 

76 

 
 
 
 
 
 
 
 
 
 
 
Table  F.15. Mass fractions of the sum of fipronil and fipronil sulfone expressed as fipronil in wheat 
based on the individual mass fractions reported by participant laboratories. The expanded 
uncertainty is estimated as the combined expanded uncertainty. 

LABORATORY 
CODE 

L01-GC-MS/MS 

L02-LC-MS/MS 

L03a-GC-MS/MS 

L03b-LC-MS/MS 

L04-LC-MS/MS 

L07-LC-MS/MS 

L08-LC-MS/MS 

L09-GC-MS/MS 

L10-GC-MS/MS 

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

0.753 

1.002 

1.148 

1.016 

0.88 

1.129 

0.771 

1.13 

0.95 

0.801 

0.953 

1.101 

1.08 

0.87 

0.974 

0.816 

1.084 

0.936 

0.833 

1.127 

1.098 

1.013 

0.973 

0.995 

0.848 

1.275 

0.964 

0.753 

1.002 

1.148 

1.016 

0.88 

1.129 

0.771 

1.13 

0.95 

0.801 

0.953 

1.101 

1.08 

0.87 

0.974 

0.816 

1.084 

0.936 

0.833 

1.127 

1.098 

1.013 

0.973 

0.995 

0.848 

1.275 

0.964 

0.796 

1.027 

1.115 

1.036 

0.908 

1.032 

0.812 

1.163 

0.950 

Expanded 
uncertainty 
[mg/kg] 
0.101 

0.388 

0.404 

0.374 

0.279 

0.203 

0.298 

0.211 

0.360 

sum fipronil + fipronil sulfone 

t
a
e
h
w
g
k
/
g
m

2.0

1.5

1.0

0.5

0.0

L01

L02

L03a

L03b

L04

L07

L08

L09

L10

Laboratory code

Figure F.15. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM 

77 

 
 
 
 
 
 
 
 
 
 
 
 
Expanded 
uncertainty 
[mg/kg] 
0.189 

0.218 

0.628 

0.387 

0.724 

0.365 

0.613 

Table F.16. Mass fractions of glyphosate in wheat as reported by participant laboratories.  

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

0.707 

1.074 

1.285 

1.321 

1.559 

1.341 

1.11 

0.709 

1.042 

1.342 

1.083 

1.504 

1.329 

1.32 

0.762 

1.301 

1.155 

1.255 

1.4769 

1.284 

1.19 

0.766 

1.225 

1.198 

1.313 

1.216 

1.284 

1.3 

0.817 

1.175 

1.204 

1.374 

0.746 

1.150 

1.255 

1.291 

1.5162 

1.448 

1.295 

1.29 

1.305 

1.227 

glyphosate

LABORATORY 
CODE 

L01-LC-MS/MS 

L02-LC-MS/MS 

L03-LC-MS/MS 

L04-LC-MS/MS 

0.713 

1.081 

1.346 

1.399 

L08-LC-MS/MS 

1.4168 

L09-LC-MS/MS 

L10-LC-MS/MS 

1.295 

1.15 

3

t
2
a
e
h
w
g
k
/
g
1
m

0

L01

L02

L03

L04

L08

L09

L10

Laboratory code

Figure F.16. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM 

78 

 
 
 
 
 
 
 
 
 
 
 
 
Table F.17. Mass fractions of imazalil in wheat as reported by participant laboratories.  

LABORATORY 
CODE 

L01-GC-MS/MS 
L02-LC-MS/MS 
L03-LC-MS/MS 
L04-LC-MS/MS 
L05-LC-MS/MS 
L06-LC-MS/MS 
L07-LC-MS/MS 
L08-LC-MS/MS 
L09-LC-MS/MS 
L10-LC-MS/MS 

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

0.235 
0.231 
0.290 
0.293 
0.257 
0.259 
0.211 
0.218 
0.235 
0.228 
0.134 
0.148 
0.332 
0.290 
0.2143  0.2141 
0.236 
0.244 
0.181 
0.190 

0.202 
0.229 
0.290 
0.306 
0.228 
0.260 
0.230 
0.210 
0.230 
0.232 
0.127 
0.137 
0.211 
0.289 
0.1941  0.1837 
0.249 
0.235 
0.190 
0.182 

0.229 
0.337 
0.229 
0.216 
0.235 
0.136 
0.211 
0.2055 
0.227 
0.189 

0.227 
0.346 
0.230 
0.216 
0.232 
0.125 
0.277 
0.195 
0.237 
0.181 

0.225 
0.310 
0.244 
0.217 
0.232 
0.135 
0.268 
0.201 
0.238 
0.186 

Expanded 
uncertainty 
[mg/kg] 
0.044 
0.155 
0.122 
0.087 
0.014 
0.036 
0.080 
0.101 
0.019 
0.093 

imazalil 

t
a
e
h
w
g
k
/
g
m

0.50

0.40

0.30

0.20

0.10

0.00

L01

L02

L03

L04

L05

L06

L07

L08

L09

L10

Laboratory code

Figure F.17. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM 

79 

 
 
 
 
 
 
 
 
 
 
Table F.18. Mass fractions of imidacloprid in wheat as reported by participant laboratories.  

LABORATORY 
CODE 

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

L01-LC-MS/MS 

0.0448 

0.0442 

0.0457 

0.0458 

0.0454 

0.0433 

0.0449 

Expanded 
uncertainty 
[mg/kg] 
0.0079 

L02-LC-MS/MS 

0.0685 

0.0611 

0.0641 

0.0625 

0.0622 

0.0585 

0.0628 

0.0314 

L03-LC-MS/MS 

0.049 

0.05 

0.05 

0.048 

0.049 

0.048 

0.0490 

0.0245 

L04-LC-MS/MS 

0.0416 

0.0383 

0.0361 

0.0384 

0.0384 

0.0394 

0.0387 

0.0155 

L06-LC-MS/MS 

0.028 

0.028 

0.026 

0.028 

0.030 

L07-LC-MS/MS 

0.0479 

0.0462 

0.0385 

0.0436 

0.0453 

0.028 

0.053 

0.0280 

0.0076 

0.0457 

0.0165 

L08-LC-MS/MS 

0.0451 

0.0437 

0.0447 

0.0465 

0.0439 

0.0419 

0.0443 

0.0222 

L09-LC-MS/MS 

0.0494 

0.0487 

0.0569 

0.0489 

0.0536 

0.0483 

0.0510 

0.0066 

L10-LC-MS/MS 

0.0389 

0.0367 

0.0322 

0.0378 

0.0334 

0.0323 

0.0352 

0.0176 

imidacloprid 

t
a
e
h
w
g
k
/
g
m

0.10

0.08

0.06

0.04

0.02

0.00

L01

L02

L03

L04

L06

L07

L08

L09

L10

Laboratory code

Figure F.18. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM 

80 

 
 
 
 
 
 
 
 
 
 
Table F.19. Mass fractions of linuron in wheat as reported by participant laboratories.  

LABORATORY 
CODE 

L01-LC-MS/MS 

L02-LC-MS/MS 

L03-LC-MS/MS 

L04-LC-MS/MS 

L05-LC-MS/MS 

L06-LC-MS/MS 

L07-LC-MS/MS 

L08-LC-MS/MS 

L09-LC-MS/MS 

L10-LC-MS/MS 

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

0.548 

0.637 

0.534 

0.49 

0.516 

0.366 

0.639 

0.568 

0.534 

0.426 

0.541 

0.666 

0.518 

0.474 

0.506 

0.366 

0.65 

0.5779 

0.615 

0.441 

0.537 

0.683 

0.532 

0.494 

0.516 

0.336 

0.442 

0.506 

0.524 

0.425 

0.454 

0.641 

0.474 

0.525 

0.516 

0.37 

0.628 

0.471 

0.674 

0.48 

0.519 

0.549 

0.361 

0.597 

0.443 

0.657 

0.468 

0.514 

0.502 

0.342 

0.659 

0.5613 

0.5194 

0.5025 

0.502 

0.422 

0.478 

0.413 

0.552 

0.426 

0.499 

0.660 

0.501 

0.503 

0.517 

0.357 

0.603 

0.539 

0.534 

0.426 

Expanded 
uncertainty 
[mg/kg] 
0.121 

0.330 

0.251 

0.201 

0.023 

0.132 

0.193 

0.270 

0.160 

0.213 

linuron

t
a
e
h
w
g
k
/
g
m

1.0

0.8

0.5

0.3

0.0

L01

L02

L03

L04

L05

L06

L07

L08

L09

L10

Laboratory code

Figure F.19. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM  

81 

 
 
 
 
 
 
 
 
 
 
Table F.20. Mass fractions of malaoxon in wheat as reported by participant laboratories.  

LABORATORY 
CODE 

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

L01-GC-MS/MS 

0.0104 

0.0083 

0.0109 

0.0104 

0.0112 

0.0115 

0.0104 

Expanded 
uncertainty 
[mg/kg] 
0.0016 

L02-LC-MS/MS 

0.0141 

0.0137 

0.0118 

0.0136 

0.0121 

0.0121 

0.0129 

0.0065 

L04-LC-MS/MS 

0.012 

0.0131 

0.0131 

0.0127 

0.0051 

L07-LC-MS/MS 

0.0136 

0.0117 

0.008 

0.0125 

0.0109 

0.0133 

0.0117 

0.0051 

L08-GC-MS/MS 

0.0076 

0.0071 

0.0076 

0.0086 

0.0082 

0.009 

0.0080 

0.0040 

L09-GC-MS/MS 

0.012 

0.0116 

0.0143 

0.0124 

0.0139 

0.0117 

0.0126 

0.0008 

L10-LC-MS/MS 

0.0101 

0.0093 

0.0089 

0.0099 

0.0099 

0.0105 

0.0098 

0.0049 

Results not used for value assignment 

L03-LC-MS/MS 

0.018 

0.02 

0.02 

0.012 

0.013 

0.013 

0.016 

0.0037 

malaoxon

t
a
e
h
w
g
k
/
g
m

0.03

0.02

0.01

0.00

L01

L02

L04

L07

L08

L09

L10

Laboratory code

Figure F.20. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM  

82 

 
 
 
 
 
 
 
 
 
 
 
 
 
Table F.21. Mass fractions of malathion in wheat as reported by participant laboratories.  

LABORATORY 
CODE 

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 6 
[mg/kg] 

Mean 
[mg/kg] 

L01-GC-MS/MS 

11.65 

11.33 

11.93 

11.18 

11.65 

12.14 

11.65 

L02-GC-MS/MS 

L03a-GC-MS/MS 

L03b-LC-MS/MS 

L05a-GC-MS/MS 

L05b-LC-MS/MS 

L07-LC-MS/MS 

7.68 

8.31 

7.82 

10.35 

11.34 

10.95 

8.96 

8.38 

7.96 

10.84 

11.49 

8.96 

7.18 

8.12 

8.35 

13.47 

10.74 

6.93 

7.81 

11.3 

10.2 

10.18 

10.97 

9.21 

7.01 

12.03 

11.14 

14.3 

10.57 

9.32 

L08-GC-MS/MS 

7.8649 

7.803 

7.9384 

7.8637 

L09-GC-MS/MS 

L10-LC-MS/MS 

8.29 

8.71 

7.99 

9.04 

10.12 

8.75 

8.73 

9.12 

9.75 

8.51 

7.96 

11.74 

10.83 

13.71 

11.08 

10.63 

8.08 

8.46 

7.77 

9.98 

9.38 

12.14 

11.03 

9.33 

7.87 

8.83 

8.77 

Expanded 
uncertainty 
[mg/kg] 
1.76 

3.88 

4.99 

4.69 

1.62 

1.48 

2.99 

3.93 

1.24 

4.38 

malathion

t
a
e
h
w
g
k
/
g
m

20

15

10

5

0

L01

L02

L03a

L03b

L05a

L05b

L07

L08

L09

L10

Laboratory code

Figure F.21. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM  

83 

 
 
 
 
 
 
 
 
 
 
 
 
 
Table F.22. Mass fractions of the sum of malathion and malaoxon expressed as malathion in wheat 
calculated based on the individual mass fractions reported by participant laboratories. The 
expanded uncertainty is estimated as the combined expanded uncertainty.  

LABORATORY 
CODE 

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 6 
[mg/kg] 

Mean 
[mg/kg] 

L01-GC-MS/MS 

11.66 

11.34 

11.94 

11.19 

11.67 

12.15 

11.66 

L02-GC-MS/MS 

L07-LC-MS/MS 

7.69 

10.97 

8.97 

8.97 

7.19 

6.94 

7.83 

9.23 

L08-GC-MS/MS 

7.8729 

7.8105 

7.9474 

7.8723 

L09-GC-MS/MS 

L10-LC-MS/MS 

8.30 

8.72 

8.00 

9.05 

10.14 

8.76 

8.74 

9.13 

7.03 

9.33 

9.76 

8.52 

7.97 

10.64 

8.09 

8.47 

7.78 

9.35 

7.88 

8.84 

8.78 

Expanded 
uncertainty 
[mg/kg] 
1.76 

3.89 

2.99 

3.94 

1.24 

4.38 

sum malathion + malaoxon

20

15

10

5

0

t
a
e
h
w
g
k
/
g
m

L01

L02

L07

L08

L09

L10

Laboratory code

Figure F.22. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM  

84 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Table F.23. Mass fractions of permethrin in wheat as reported by participant laboratories.  

LABORATORY 
CODE 

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

L01-GC-MS/MS 

0.276 

0.313 

0.294 

L02-GC-MS/MS 

L03-GC-MS/MS 

L04-GC-MS/MS 

L05-GC-MS/MS 

L06-GC-MS/MS 

L07-GC-MS/MS 

0.65 

0.498 

0.345 

0.548 

0.275 

0.34 

0.61 

0.475 

0.34 

0.539 

0.271 

0.314 

0.51 

0.467 

0.348 

0.523 

0.252 

0.336 

0.25 

0.44 

0.479 

0.392 

0.535 

0.272 

0.298 

0.284 

0.51 

0.474 

0.375 

0.512 

0.278 

0.332 

0.29 

0.61 

0.478 

0.355 

0.511 

0.296 

0.317 

L08-GC-MS/MS 

0.4837 

0.4926 

0.4992 

0.5018 

0.5119 

0.4963 

L09-GC-MS/MS 

L10a-GC-MS/MS 

L10b-LC-MS/MS 

0.439 

0.314 

0.372 

0.426 

0.314 

0.371 

0.512 

0.331 

0.389 

0.411 

0.316 

0.358 

0.476 

0.32 

0.374 

0.417 

0.324 

0.367 

0.285 

0.556 

0.479 

0.359 

0.528 

0.274 

0.323 

0.498 

0.447 

0.320 

0.372 

Expanded 
uncertainty 
[mg/kg] 
0.097 

0.278 

0.239 

0.144 

0.087 

0.036 

0.136 

0.249 

0.130 

0.160 

0.186 

permethrin

t
a
e
h
w
g
k
/
g
m

1.0

0.8

0.6

0.4

0.2

0.0

L01

L02

L03

L04

L05

L06

L07

L08

L09

L10a

L10b

Laboratory code

Figure F.23. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM  

85 

 
 
 
 
 
 
 
 
 
 
 
Table F.24. Mass fractions of tebuconazole in wheat as reported by participant laboratories.  

LABORATORY 
CODE 

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

L01-GC-MS/MS 

0.0217 

0.0266 

0.0253 

0.0238 

0.0257 

0.0264 

0.0249 

Expanded 
uncertainty 
[mg/kg] 
0.0065 

L02-LC-MS/MS 

0.0675 

0.0622 

0.0604 

0.0612 

0.0639 

0.0603 

0.0626 

0.0313 

L03-LC-MS/MS 

0.046 

0.048 

0.048 

0.046 

0.048 

0.046 

0.0470 

0.0235 

L04-GC-MS/MS 

0.0383 

0.0383 

0.0361 

0.0416 

0.0384 

0.0373 

0.0383 

0.0153 

L05a-GC-MS/MS 

0.0423 

0.0408 

0.0424 

0.0421 

0.0411 

0.0409 

0.0416 

0.0090 

L05b-LC-MS/MS 

0.0445 

0.0448 

0.0447 

0.0452 

0.0464 

0.0452 

0.0451 

0.0077 

L06-GC-MS/MS 

0.031 

0.0331 

0.0316 

0.0333 

0.0319 

0.0326 

0.0322 

0.0045 

L07-GC-MS/MS 

0.0396 

0.0380 

0.0387 

0.0361 

0.0384 

0.0373 

0.0380 

0.0152 

L08-GC-MS/MS 

0.0392 

0.0398 

0.0460 

0.0409 

0.0461 

0.0447 

0.0428 

0.0214 

L09-LC-MS/MS 

0.0348 

0.0512 

0.0384 

0.0395 

0.0457 

0.0450 

0.0424 

0.0068 

L10-LC-MS/MS 

0.0378 

0.0367 

0.0378 

0.0378 

0.0378 

0.0390 

0.0378 

0.0189 

tebuconazole

0.10

0.08

0.06

0.04

0.02

0.00

t
a
e
h
w
g
k
/
g
m

L01

L02

L03

L04

L05a

L05b

L06

L07

L08

L09

L10

Laboratory code

Figure F.24. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM 

86 

 
 
 
 
 
 
 
 
 
 
 
Table F.25. Mass fractions of thiabendazole in wheat as reported by participant laboratories.  

LABORATORY 
CODE 

L01-LC-MS/MS 

L02-LC-MS/MS 

L03-LC-MS/MS 

L04-LC-MS/MS 

L05-LC-MS/MS 

L06-LC-MS/MS 

L07-LC-MS/MS 

Replicate 
1 [mg/kg] 

Replicate 
2 [mg/kg] 

Replicate 
3 [mg/kg] 

Replicate 
4 [mg/kg] 

Replicate  
5 [mg/kg] 

Replicate 
6 [mg/kg] 

Mean 
[mg/kg] 

0.409 

0.486 

0.485 

0.429 

0.471 

0.329 

0.361 

0.413 

0.490 

0.501 

0.425 

0.485 

0.329 

0.398 

0.398 

0.442 

0.499 

0.453 

0.481 

0.309 

0.338 

0.419 

0.467 

0.491 

0.457 

0.469 

0.333 

0.341 

0.419 

0.467 

0.492 

0.447 

0.482 

0.323 

0.352 

0.402 

0.485 

0.485 

0.437 

0.471 

0.323 

0.439 

Expanded 
uncertainty 
[mg/kg] 
0.113 

0.236 

0.246 

0.177 

0.013 

0.055 

0.134 

0.177 

0.073 

0.161 

0.410 

0.473 

0.492 

0.441 

0.477 

0.324 

0.372 

0.355 

0.427 

0.322 

L08-LC-MS/MS 

0.3688 

0.3514 

0.3533 

0.3548 

0.3496 

0.3493 

L09-LC-MS/MS 

L10-LC-MS/MS 

0.437 

0.346 

0.436 

0.329 

0.412 

0.318 

0.411 

0.327 

0.410 

0.306 

0.453 

0.303 

thiabendazole

t
a
e
h
w
g
k
/
g
m

0.8

0.6

0.4

0.2

0.0

L01

L02

L03

L04

L05

L06

L07

L08

L09

L10

Laboratory code

Figure F.25. Laboratory means with the expanded uncertainty as stated by the laboratory 
represented as error bars. Red lines correspond to the mean of laboratory means ± UCRM 

87 

 
 
 
 
 
 
 
 
 
 
88 

 
 
 
European Commission 

The certification of the mass fraction of pesticides in wheat flour: ERM®-BC706 

EUR 30972 EN – Joint Research Centre – Directorate F – Health, Consumers and Reference Materials 
Title:  
Author(s): B. Sejerøe-Olsen, P. Shegunova, S. Harbeck, J. Seghers, M. E. Poulsen, M. Dabrio 
Luxembourg: Publications Office of the European Union 
2022 –88 pp. – 21.0 x 29.7 cm 
EUR – Scientific and Technical Research series – ISSN 1831-9424 
ISBN 978-92-76-46990-2 
doi:10.2760/919535 

 
 
 
 
 
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 methods, tools and standards, and sharing its know-
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Key policy areas include: environment and climate change; energy and transport; agriculture and food 
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including nuclear; all supported through a cross-cutting and multi-disciplinary approach. 

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doi:10.2760/919535 

ISBN: 978-92-76-46990-2