CEN/TS 17061:2019

SLOVENSKI STANDARD
01-november-2019
Nadomešča:
SIST-TS CEN/TS 17061:2017
Živila - Smernice za kalibracijo ter kvantitativno določanje ostankov pesticidov in
organskih onesnaževal z uporabo kromatografskih metod
Foodstuffs - Guidelines for the calibration and quantitative determination of pesticide
residues and organic contaminants using chromatographic methods
Lebensmittel - Anleitung zur Kalibrierung und quantitativer Bestimmung von
Pflanzenschutzmittelrückständen und organischen Kontaminanten mit
chromatographischen Verfahren
Produits alimentaires - Lignes directrices pour l’étalonnage et le dosage des résidus de
pesticides et contaminants organiques par des méthodes chromatographiques
Ta slovenski standard je istoveten z: CEN/TS 17061:2019
ICS:
67.050 Splošne preskusne in General methods of tests and
analizne metode za živilske analysis for food products
proizvode
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

CEN/TS 17061
TECHNICAL SPECIFICATION
SPÉCIFICATION TECHNIQUE
September 2019
TECHNISCHE SPEZIFIKATION
ICS 67.050 Supersedes CEN/TS 17061:2017
English Version
Foodstuffs - Guidelines for the calibration and quantitative
determination of pesticide residues and organic
contaminants using chromatographic methods
Produits alimentaires - Lignes directrices pour Lebensmittel - Anleitung zur Kalibrierung und
l'étalonnage et le dosage des résidus de pesticides et quantitativer Bestimmung von
contaminants organiques par des méthodes Pflanzenschutzmittelrückständen und organischen
chromatographiques Kontaminanten mit chromatographischen Verfahren
This Technical Specification (CEN/TS) was approved by CEN on 14 July 2019 for provisional application.

The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to
submit their comments, particularly on the question whether the CEN/TS can be converted into a European Standard.

CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS
available promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in
parallel to the CEN/TS) until the final decision about the possible conversion of the CEN/TS into an EN is reached.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 17061:2019 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 Principle . 4
5 General . 4
6 Execution and calculation of calibrations . 5
6.1 General/specifications . 5
6.2 Calibration functions . 7
6.3 Test for matrix effects . 9
6.4 Basic calibration and calibration by means of external standard. 9
6.5 Calculation by means of internal standard . 11
6.6 Calibration using standard addition procedures . 15
6.7 Procedural calibration . 17
6.8 Calibration with chemical conversion of the standard . 17
7 Quality assurance . 17
7.1 Qualification of the chromatographic system . 17
7.2 Examination of integration results . 18
7.3 Permissible blank values in relation to the lower limit of working range . 18
7.4 Frequency of calibrations . 19
7.5 Number of analytes to be calibrated for “multi-methods” . 19
7.6 Handling of substances with multiple peaks . 19
7.7 Quality control chart . 19
8 Expression of results (units, number of significant figures) . 22
9 Examples . 22
9.1 Example 1 — Test for variance inhomogeneity . 22
9.2 Example 2 — Selection of appropriate calibration function . 23
9.3 Example 3 — Test for matrix effects . 30
9.4 Example 4 — Calibration with external standard . 31
9.5 Example 5 — Calibration with internal standard . 33
9.6 Example 6 — Calculation with stable-isotope labelled standard . 34
9.7 Example 7 — Standard addition to final extract . 35
Annex A (informative) Abbreviations . 37
Bibliography . 39

European foreword
This document (CEN/TS 17061:2019) has been prepared by Technical Committee CEN/TC 275 “Food
analysis - Horizontal methods”, the secretariat of which is held by DIN.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document will supersede CEN/TS 17061:2017.
Compared to CEN/TS 17061:2017, the following changes have been made:
— Annex A (informative) containing a list of abbreviations was added;
— The document has been editorially revised.
— Annex A (informative) contains a list of abbreviations.
According to the CEN/CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
1 Scope
This Technical Specification gives guidelines for the execution of calibration and quantitative evaluation
of chromatographic procedures for the determination of pesticides and organic contaminants in residue
analysis. In addition, the essential requirements for calibration are outlined.
The calibration of analytical procedures and the evaluation of analytical results need to be conducted
according to uniform principles in order to allow for a comparison of analytical results (even from
different analytical procedures). They constitute the basis of any method validation and of the quality
assurance within laboratories [1], [2], [3].
This Technical Specification does not consider issues of identification/qualification and extraction
efficiency.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
4 Principle
This document describes the approach for the calibration of chromatographic procedures. The
following types of calibration are discussed in more detail:
— external calibration with linear calibration function;
— external calibration with quadratic calibration function;
— calibration with internal standard and linear calibration function;
— calibration with internal standard and quadratic calibration function;
— calibration with standards labelled with stable isotopes (isotopic dilution analysis);
— standard addition to final extract;
— standard addition to sample.
For this purpose, the calibration function and the selection criteria are illustrated on the basis of
examples. The calculation formulae refer to the final extract ready for analysis (“test solution”).
The description is rounded off by essential items of quality assurance, e.g. the qualification of
chromatographic systems or the quality control chart.
5 General
Calibration of a system is understood as the determination of a functional relationship between a
measurable quantity and a concentration to be determined. The chosen type of calibration depends on
the various analytical problems/tasks. It is performed in connection with the respective series of
measurements.
Basic calibration is regarded as the determination of the functional relationship when an analyte is to be
determined for the first time by means of a particular measurement system.
Depending on the problem and on the type of reference solution used, it is distinguished between:
— calibration with external standard;
— calibration with internal standard;
— calibration with standard addition;
— calibration of the entire procedure.
In case of the calibration with external standard, the calibration solutions can be prepared either with a
pure solvent (standards in solvent) or with sample extracts which evidently do not contain significant
amounts of the analyte(s) (matrix-matched standards).
The application of a simple linear-regression calculation requires a linear relationship between the
content of substance and the measured value. The linearity test can be performed visually and/or
mathematically. A mathematical check is performed, e.g. by means of the goodness-of-fit test according
to Mandel or by means of residual analysis. The residuals are the deviations of the measurement values
from the values predicted by the regression line (see 9.1, Example 1).
6 Execution and calculation of calibrations
6.1 General/specifications
6.1.1 Working range
The range of measurement represented by the lowest and the highest calibration point constitutes the
range of concentrations for which the determined calibration function applies (working range). Only
within this range, the measured values are reliable and, therefore, can be used for the calculation of
analyte contents. At the upper and lower end, the prediction interval becomes wider i.e. the
measurement error increases progressively. The highest precision is found in the middle of the working
range [4].
The detector response from the analytes in the sample extract has to lie within the working range.
Extracts containing residues above the calibrated range shall be diluted. If the calibration solutions are
matrix-matched the matrix concentration in the calibration standards should also be diluted, see [5].
The calibration range shall be adjusted to the respective residue concentrations in the test solution
(real-sample concentrations which often occur in practice) and should cover a maximum of two orders
of magnitudes. Where appropriate, several calibration functions shall be established by means of
calibration solutions.
The lower limit of the practical working range usually represents the lowest calibration level, see [5]. I
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