SIST-TS CEN/TS 17062:2017
(Main)Foods of plant origin - Multimethod for the determination of pesticide residues in vegetable oils by LC-MS/MS
Foods of plant origin - Multimethod for the determination of pesticide residues in vegetable oils by LC-MS/MS
This European Technical Specification describes a method for the analysis of pesticide residues in plant oils (fat content > 90 %, water content < 5 %). It has been validated in an interlaboratory test with olive oil. However, laboratory experiences are available also for other kind of oils such as sunflower seed oil, sesame oil, flax seed oil, rape seed oil, grape seed oil, thistle oil and pumpkin seed oil.
Pflanzliche Lebensmittel - Multiverfahren zur Bestimmung von Pestizidrückständen in pflanzlichen Ölen mit LC-MS/MS
Diese europäische Technische Spezifikation beschreibt ein Verfahren zur Bestimmung von Pflanzenschutzmittel-Rückständen in pflanzlichen Ölen (Fettgehalt > 90 %, Wassergehalt < 5 %). Das Verfahren wurde in einem Ringversuch mit Olivenöl validiert. Laborerfahrungen sind jedoch auch bei anderen Ölsorten wie Sonnenblumenöl, Sesamöl, Leinöl, Rapsöl, Traubenkernöl, Distelöl und Kürbiskernöl vorhanden.
Aliments d'origine végétale - Multiméthode de détermination des résidus de pesticides dans les huiles végétales par CL-SM/SM
La présente Spécification technique européenne décrit une méthode d’analyse des résidus de pesticides dans les huiles végétales (teneur en matière grasse > 90 %, teneur en eau < 5 %). Elle a été validée lors d’un essai interlaboratoire avec de l’huile d’olive. Toutefois, les expériences menées en laboratoire sont également disponibles pour d’autres types d’huiles telles que l’huile de tournesol, l’huile de sésame, l’huile de lin, l’huile de colza, l’huile de pépins de raisin, l’huile de chardon et l’huile de pépins de courge.
Hrana rastlinskega izvora - Večelementna metoda za določanje ostankov pesticidov v rastlinskih oljih z LC-MS/MS
Ta evropska tehnična specifikacija določa metodo za analizo ostankov pesticidov v rastlinskih oljih (vsebnost maščob > 90 %, vsebnost vode < 5 %). Potrjena je bila v okviru medlaboratorijskega preskusa z olivnim oljem. Rezultati laboratorijskih preskusov pa so na voljo tudi za druga olja, kot so olje iz sončničnih semen, sezamovo olje, olje iz lanenih semen, olje iz oljne repice, olje grozdnih pečk, olje iz semen žafranike in bučno olje.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST-TS CEN/TS 17062:2017
01-november-2017
+UDQDUDVWOLQVNHJDL]YRUD9HþHOHPHQWQDPHWRGD]DGRORþDQMHRVWDQNRY
SHVWLFLGRYYUDVWOLQVNLKROMLK]/&0606
Foods of plant origin - Multimethod for the determination of pesticide residues in
vegetable oils by LC-MS/MS
Pflanzliche Lebensmittel - Multiverfahren zur Bestimmung von Pestizidrückständen in
pflanzlichen Ölen mit LC-MS/MS
Aliments d'origine végétale - Multiméthode de détermination des résidus de pesticides
dans les huiles végétales par CL-SM/SM
Ta slovenski standard je istoveten z: CEN/TS 17062:2017
ICS:
67.050 Splošne preskusne in General methods of tests and
analizne metode za živilske analysis for food products
proizvode
67.200.10 5DVWOLQVNHLQåLYDOVNH Animal and vegetable fats
PDãþREHLQROMD and oils
SIST-TS CEN/TS 17062:2017 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST-TS CEN/TS 17062:2017
CEN/TS 17062
TECHNICAL SPECIFICATION
SPÉCIFICATION TECHNIQUE
September 2017
TECHNISCHE SPEZIFIKATION
ICS 67.050
English Version
Foods of plant origin - Multimethod for the determination
of pesticide residues in vegetable oils by LC-MS/MS
Aliments d'origine végétale - Multiméthode de Pflanzliche Lebensmittel - Multiverfahren zur
détermination de la teneur en résidus de pesticides Bestimmung von Pestizidrückständen in pflanzlichen
dans les huiles végétales par CL-SM/SM Ölen mit LC-MS/MS
This Technical Specification (CEN/TS) was approved by CEN on 11 May 2017 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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, 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: Avenue Marnix 17, B-1000 Brussels
© 2017 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 17062:2017 E
worldwide for CEN national Members.
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Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Principle . 4
4 Reagents . 4
5 Apparatus . 7
6 Procedure. 7
7 Evaluation of results . 9
8 Precision . 10
9 Test report . 11
Annex A (informative) Examples of experimental conditions . 12
A.1 HPLC-System 1. 12
A.2 HPLC-System 2. 12
A.3 HPLC-System 3. 13
A.4 HPLC system 4 . 13
Annex B (informative) Precision data and recovery . 15
Annex C (informative) Scheme of procedure (for 2 g of sample) . 24
Annex D (informative) Complementary information - Recovery studies . 25
Bibliography . 26
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European foreword
This document (CEN/TS 17062:2017) 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.
WARNING — The application of this Technical Specification may involve hazardous materials,
operations and equipment. This Technical Specification does not claim to address all the safety
problems associated with its use. It is the responsibility of the user of this Technical
Specification to establish appropriate safety and health practices and to determine the
applicability of regulatory limitations prior to use.
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, Former Yugoslav Republic of Macedonia,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
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1 Scope
This Technical Specification describes a method for the analysis of pesticide residues in plant oils (fat
content > 90 %, water content < 5 %). It has been validated in an interlaboratory test with olive oil.
However, laboratory experiences are available also for other kind of oils such as sunflower seed oil,
sesame oil, flax seed oil, rape seed oil, grape seed oil, thistle oil and pumpkin seed oil.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
CEN/TS 17061:2017, Foodstuffs — Guideline for the calibration and quantitative determination of
chromatographic methods for the determination of pesticide residues and organic contaminants
3 Principle
The homogeneous sample is extracted with acetonitrile. After centrifugation, an aliquot of the organic
phase is cleaned-up by dispersive solid phase extraction (D-SPE; sorbents PSA and C18). To separate
co-extracted fat a freeze-out step of the acetonitrile phase can be applied. After clean up an additional
centrifugation step is performed. The extracts are acidified by adding a small amount of formic acid, to
improve the storage stability of certain base-sensitive pesticides. The final extract can be directly used
for LC-MS/MS analysis. A scheme of the procedure is given in Annex C.
NOTE In contrast to the method described in EN 15662 [1], this procedure does not include any addition of
water.
4 Reagents
Unless otherwise specified, use reagents of recognized analytical grade. Take every precaution to avoid
possible contamination of water, solvents, sorbents, inorganic salts, etc.
4.1 Water, HPLC quality.
4.2 Acetonitrile, HPLC quality.
4.3 Methanol, HPLC quality.
4.4 Acetic acid.
4.5 Ammonium formate.
4.6 Formic acid solution in acetonitrile, volume concentration σ = 5 ml formic acid/100 ml :
Dilute 5 ml of formic acid (mass fraction w ≥ 95 %) to 100 ml with acetonitrile (4.2).
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1)
®
4.7 Primary secondary amin sorbent (PSA), e.g. Bondesil-PSA 40 µm Agilent No. 12213023 .
Other amino sorbents may be used, but investigations may be necessary to prove equivalency especially
regarding analyte losses and pH value of the end extracts.
4.8 C-18-sorbent (Octadecyl-silyl-modified silica gel), Bulk material 50 µm.
4.9 Internal standard and quality control standard solutions in acetonitrile, mass concentration
ρ = 10 µg/ml to 100 µg/ml.
Table 1 shows a list of potential internal standards (ISTDs) and quality control (QC) standards that may
be used in this method.
Table 1 — Potential internal standards (ISTDs) or quality control (QC) standards
Compound Log P Suggested MS/MS MS/MS
(octanol-water concentration ESI (+) ESI (-)
partition C
ISTD
coefficient) [µg/ml]
Tris-(1,3-dichlorisopropyl)- 3,65 10 +++ +
phosphate
Linuron-D6 3,00 10 ++
Carbofuran-D3 1,80 10 ++
Chlorpyrifos-D10 4,70 10 +++
Bis-nitrophenyl urea 3,76 10 - +++
(nicarbazin)
4.10 Primary pesticide standards:
Use standards of known purity, only.
4.11 Pesticide stock solutions:
Prepare individual stock solutions of analytical standards at concentrations that are sufficient to allow
the preparation of complex pesticide working solutions that are used for the preparation of standard
solutions.
Usually, store stock solutions at ≤ −18 °C. Check the stability of stock solutions during storage regularly
[2]. In some cases the addition of acids or bases can be helpful to enhance stability and extend the
acceptable storage period. Before withdrawing any aliquot from this solution redissolve any
precipitation that may have occurred.
4.12 Pesticide working solutions:
Because of the broad applicability of this method and due to the partly divergent pH-stability of
pesticides, more than one working solution each containing one or more pesticides can be needed to
cover the entire pesticide spectrum of interest. These are prepared by mixing together defined volumes
of the required pesticide stock solutions (4.11) and appropriately diluting them with acetonitrile. The
1)
®
Bondesil-PSA is a product supplied by Agilent. This information is given for the convenience of users of this
European Technical Specification and does not constitute an endorsement by CEN of the product named.
Equivalent products may be used if they can be shown to lead to the same results.
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pesticide concentrations in these mixtures should be sufficient to allow the preparation of the required
matrix matched standards (4.13.2) with moderate dilution of the blank sample extract (e.g. less than
20 %).
Usually, pesticide working solutions should be stored at low temperature in the dark. Check the stability
of pesticides contained in these mixtures during storage regularly [2] and adapt the storing conditions
accordingly. In some cases the addition of acids or bases can be helpful to enhance stability and extend
acceptable storage times.
4.13 Standard solutions (calibration mixtures):
4.13.1 Solvent-based standards:
Prepare solvent-based standards by mixing known volumes of the pesticide working solutions (4.12)
and make up to volume with acetonitrile. The preparation of solvent based calibration mixtures with
cal cal
different analyte concentrations (ρ ) and identical internal standard concentrations (ρ ) is
A ISTD
necessary to create a calibration graph.
cal
The concentration of the internal standards in the calibration mixtures (ρ ) shall be equivalent to
ISTD
the concentration of the internal standard in the sample extracts, as the internal standards are added
after extraction.
cal cal
The quotient V /V from the volume used (V ) shall be equivalent to the solution of the internal
ISTD Std ISTD
standard (4.9) and the final volume of the calibration standards (V ) shall be equivalent to the
Std
quotient V /V (see 6.1). If 60 µl ISTD solution (4.9) are added to 6 ml of aliquot of the
ISTD Aliquot
centrifugate, 6 ml of standard solution shall be spiked with 60 µl of ISTD solution. If other volumes of
calibration standards are used, the addition of ISTD solution shall be adjusted.
NOTE A pesticide concentration of 1 µg/ml correlates to a residue level of 5 mg/kg when a 2 g test portion is
employed.
4.13.2 Matrix-matched standards:
Prepare matrix-matched standards in the same way as solvent-based standards, however, instead of
pure acetonitrile use extracts of blank samples (samples, where no pesticides have been found with this
method). The extract is prepared as described in Clause 5 (but without ISTD addition). To minimize
errors caused by matrix induced effects during chromatography, it is best to choose similar
commodities (e.g. olive oil for olive oil samples etc.).
The stability of pesticides in matrix-matched standards can be lower than that of standards in pure
acetonitrile and has to be checked more thoroughly.
4.14 Mobile phase A :
1
Ammonium formate solution in water for HPLC, ρ = 0,315 g ammonium formate / 1 000 ml, substance
concentration c = 5 mmol/l.
4.15 Mobile phase B :
1
Ammonium formate solution in methanol for HPLC, ρ = 0,315 g ammonium formate / 1 000 ml,
c = 5 mmol/l.
4.16 Mobile phase A :
2
Acetic acid solution in water, add 0,1 ml of glacial acetic acid to 1 000 ml of water.
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4.17 Mobile phase B :
2
Acetic acid solution in acetonitrile, add 0,1 ml of glacial acetic acid to 1 000 ml of acetonitrile.
4.18 Mobile phase A :
3
Methanol/water 2+8 (V/V) with 5 mmol/l ammonium formate, ρ = 0,315 g ammonium formate /
1 000 ml.
4.19 Mobile phase B :
3
Methanol/water 9+1 (V/V) with 5 mmol/l ammonium formate, ρ = 0,315 g ammonium formate /
1 000 ml.
4.20 Cotton wool.
5 Apparatus
Usual laboratory apparatus and, in particular, the following:
5.1 Automatic pipettes, suitable for handling volumes of 10 µl to 100 µl, 200 µl to 1 000 µl and 2 ml
to 10 ml.
NOTE Instead of the latter, 10 ml graduated glass pipettes can be used alternatively.
5.2 Single use centrifuge tubes with screw caps, 50 ml
EXAMPLES
a) 50 ml centrifuge tubes made of poly-tetrafluoroethylene with screw caps; or
b) disposable 50 ml polypropylene centrifuge tubes with screw caps
5.3 Polypropylene-single use tubes with screw caps, 10 ml or 12 ml
5.4 Centrifuges, suitable for the centrifuge tubes employed in the procedure (6.2.2 and 6.2.3) and
capable of achieving at least 1 000 g.
5.5 10 ml solvent-dispenser for acetonitrile, for use with the acetonitrile reservoir bottle.
5.6 Injection vials, 1,5 ml, suitable for LC autosampler, if necessary with micro-inserts.
5.7 Vibration device, e.g. Vortex (used for recovery studies).
5.8 Freezer, > 60 l, ≤ –18 °C.
5.9 LC-MS/MS system, equipped with electrospray ionization (ESI) interface (see Annex A).
6 Procedure
6.1 Extraction
Transfer a representative test portion of 2 g (m ) of the homogenous sample into a 50 ml centrifuge
sample
tube (5.2). Add 10 ml of acetonitrile (4.2 V ). Close the tube and shake vigorously for 1 min. Centrifuge
ex
for 5 min with at least 1 000 g for better separation of the phases.
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Transfer an aliquot of the acetonitrile phase V (e.g. 6 ml extract) into a tube with screw cap (5.3).
Aliquot
Add a defined volume (V ) of the ISTD solution (4.9). The volume corresponds to 1 % of the aliquot
ISTD
volume (e.g. 60 µl ISTD solution to 6 ml acetonitrile phase).
6.2 Clean-up
6.2.1 General
The two different clean-up methods described in 6.2.2 and 6.2.3 were successfully validated and may be
used alternatively.
6.2.2 Clean-up with amino-sorbent and silica-based reversed phase sorbent
Transfer an aliquot of 4 ml of the acetonitrile phase (6.1) into a Polypropylene single use tube (5.3)
already containing 100 mg of PSA (4.7) and 100 mg of C18 sorbent (4.8). Close the tube, shake
vigorously for 30 s and centrifuge (5 min at ≥ 1 000 g). Immediately isolate and acidify the clear extract
as described in 6.2.4.
In case residues with acetic groups (e.g. phenoxy carboxylic acids) shall be determined, a second aliquot
of the centrifuged extract from 6.1 is filled into an injection vial and analysed directly with LC-MS(/MS)
to avoid losses of acidic groups by PSA clean-up.
25 mg PSA and 25 mg C18 sorbent are needed per ml of extract.
6.2.3 Freezing-out of co-extracted fat and clean-up with amino-sorbent
Store an aliquot of the extract from 6.1 containing the internal standard for at least 1,5 h at ≤ - 18 °C to
freeze out most of the fat in the extract. For separation of the latter filter the extract over cotton wool
(4.20). Take 4 ml from the cold and fat separated solution for dispersive SPE.
Transfer an aliquot of 4 ml of the acetonitrile phase into a Polypropylene single use tube (5.3) already
containing 100 mg of PSA (4.7). Close the tube, shake vigorously for 30 s and centrifuge (5 min at ≥ 1
000 g). Immediately isolate and acidify the clear extract as described in 6.2.4.
If residues with acetic groups shall be determined, transfer a second aliquot into an injection vial and
analyse directly with LC-MS(/MS) to avoid losses of acidic groups with PSA clean-up.
NOTE It is helpful to load the centrifuge tubes with the dispersive SPE sorbents before beginning the
extraction procedure needed for one batch of samples. 25 mg PSA sorbent are needed per ml of extract.
6.2.4 Extract stabilization
Transfer an aliquot of 3 ml of the cleaned-up extract from 6.2.2 or 6.2.3 into a screw cap storage vial
(5.3), taking care to avoid sorbent particles of being carried over, and slightly acidify by adding 30 µl of
a 5 % formic acid solution in acetonitrile (4.6). Transfer the pH-adjusted extract into auto-sampler vials
and use it for liquid chromatographic analysis. Store the residual extract in a refrigerator to be used if
necessary.
For 1 ml extract 10 µl of the formic acid solution (4.6) are necessary.
6.3 Determination by liquid chromatography with tandem mass spectrometry (LC-
MS/MS)
Inject the sample extracts derived from 6.2.2 to 6.2.4 and standard solutions (4.13) into the LC
instruments in an appropriate sequence. This may involve bracketing of the sample extracts with the
calibration solutions.
The measurement may be performed using various instruments, instrument parameters and columns.
Some instrument parameters and columns are listed in Annex A. These conditions have been shown to
provide satisfactory results, but are provided as examples, only.
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For some gradient/column combinations it is necessary to mix the extract with water or the aqueous
mobile phase to achieve a sufficient separation of the analytes.
NOTE If extracts are diluted with water or aqueous mobile phases it is important to avoid that non-polar
parts of the extract precipitate or emulsions occur. This could lead to losses of lipophilic analytes. In this case an
injection applying an injector programme can be helpful (see A.4).
The chromatographic conditions as outlined in Annex A have been shown to be satisfactory.
Suitable experimental conditions of LC-MS/MS measurements are outlined in CEN/TR 15641 [3].
Nevertheless, individual tuning of the compounds on the instrument that is used for measurement
usually provides better sensitivities.
7 Evaluation of results
7.1 Identification and quantification
For the identification of residues in the final extract, use relative retention time ratio against the ISTD
(Rt /Rt ) obtained from the same run. Check positive results by comparing the intensity ratios
(A) (ISTD)
between the SIM masses (m/z) or SRM transitions of the analyte. The expected intensity ratios can be
determined with the standard solutions. If the ratios of the samples and the standards have a variation
of more than 20 %, the rules of EU Quality Control Procedures have to be followed [2]. According to
these procedures positive results shall be ensured by using additional measures, e.g. additional SIM
masses or SRM transitions or other chromatographic conditions (column, eluents).
For calibration and for checking the linearity of detection of each substance, plot the peak area ratio or
cal cal
peak height ratio of pesticide and internal standard y / y (if an internal standard is used) versus
A ISTD
cal cal
the concentration ratio of the analyte against the ISTD ( / ) in the standard solution (4.13). If
ρ ρ
A ISTD
cal
no internal standards are used, plot the peak areas or peak height y against the concentration of the
A
cal
analyteρ .
A
The calibration area shall be adapted to the residue concentration and should not exceed a decimal
power. Possibly more calibration graphs shall be established using the standard solution. The
calibration function is selected according to CEN/TS 17061:2017, 4.2.1.
For a first estimation of the residue level or for the verification of absence of residues, solvent based
standards (4.13.1) can be used. They can also be used for quantification, if it was shown that no
enhancement or suppression of the analyte signal through matrix occurs. If relevant residue levels are
observed (e.g. with possible MRL violation) matrix matched standard shall be preferred for exact
quantification.
7.2 Calculation of residue concentrations using the internal standard
The determination of the concentration of the analyte ρ in the final extract is performed by using the
A
measured peak area ratio or peak height ratio from pesticide and internal standard y /y in the
A ISTD
sample as described in CEN/TS 17061. The mass fraction w of the analyte in the sample, in milligram
per kilogram, is calculated with Formula (1):
ρ × V
A ex
w= (1)
m
Sample
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where
ρ is the mass concentration of the analyte in the final extract, in microgram per millilitre;
A
Vex is the volume of acetonitrile used in 6.1, in millilitre;
m is the mass of test portion in 6.1, in gram.
Sample
7.3 Calculation of residue concentrations without internal standards
Determine the concentration of the analyte ρ in the final extract by using the measured peak area or
A
peak height from pesticide y in the sample as described in of CEN/TS 17061:2017, 4.4.2 to 4.4.5.
A
Calculate the mass fraction w of the analyte in the sample by using Formula (1).
7.4 Calculation of residue concentration using the standard additions approach
In case of suspected violative residues, or for compounds which are known to be strongly affected by
matrix-induced enhancement or suppression phenomena, standard additions are recommended
provided that the function between response and concentrations at the concentration range in question
is linear.
In case of the standard addition to the final extract, determine the concentration of the analyte ρ in the
A
final extract using a linear regression graph of peak areas or peak height versus spiked concentrations
and the volume of the applied aliquot of the final extract as described in of CEN/TS 17061:2017, 4.6.1.
Calculate the mass fraction w of the analyte in the sample by using Formula (1).
In case of standard addition to the sample, determine the mass of the analyte in the weighted sample
using a linear regression graph of peak areas or peak height versus spiked analyte masses as described
in CEN/TS 17061:2017, 4.6.2. The mass fraction of the analyte in the sample is the quotient of the mass
of the analyte m in the weighted sample and the weighted sample m .
Sample
A
NOTE With the standard addition approach, the sought analyte concentration is determined using linear
extrapolation. Therefore, it is important that the analyte has linear detection properties in the investigated
calibration range. It can be necessary to dilute the extract to achieve the calibration range using LC-MS(/MS).
8 Precision
The method was validated in two interlaboratory tests with representative analytes. The results for LC-
MS/MS validation and ongoing verification are shown in Annex B. An updated and detailed list of
validation results can be found in the internet www.eurl-pesticides-datapool.eu operated by the EU
reference laboratories for pesticides residues. A summary of the validation data are given in Table B.1
in Annex B. Data for compounds are given there if these were available from at least two laboratories
and if the number of individual results was at least five (in total). Further information on how to
conduct recovery studies is given in Annex D.
Tested matrices were vegetable oils such as olive oil, sunflower seed oil, sesame oil, flax seed oil, rape
seed, oil, grape seed oil, thistle oil and pumpkin seed oil, see www.eurl-pesticides-datapool.eu.
However, it has been noted that coconut oils containing a high amount of short chain fatty acids can
cause problems as they behave in a different way to the other oils.
With addition of the levels 0,01 mg/kg to 0,10 mg/kg the recoveries obtained were usually between
70 % and 110 %.
The detection limits are depending on the analyte of interest and the sensitivity of the equipment. In
general, pesticide residues of 0,01 mg/kg (lowest maximum residue level in most cases) can be
analysed with modern systems.
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9 Test report
The test report shall contain at least the following:
— all information necessary for the identification of the sample;
— a reference to this Technical Specification;
— the results and the units in which the results have been expressed;
— the date and type of sampling procedure (if possible);
— the date of receipt of sample in the laboratory;
— the date of test;
— any particular observations made in the course of the test;
— any operations not specified in the method or regarded as optional which might have affected the
results.
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Annex A
(informative)
Examples of experimental conditions
The following LC-MS operating conditions have been shown to be satisfactory.
A.1 HPLC-System 1
For most LC-amenable compounds:
Column Zorbax XDB C18, length 150 mm, inner diameter 2,1 mm, particle size 3,5 µm
Mobile phase A1 (4.14) Ammonium formate solution in water, c = 5 mmol/l
Mobile phase B1 (4.15) Ammonium formate solution in methanol, c = 5 mmol/l
Column temperature 40 °C
Injection volume 3 µl
Table A.1 — Flow rate and elution gradient
Time Flow Mobile phase A Mobile phase B
1 1
min rate % %
µl/min
0 300 50 50
20 300 0 100
25 300 0 100
26 300 50 50
30 300 50 50
A.2 HPLC-System 2
For polar compounds (e.g. with log P < 0,5) that show low retention at reversed-phased columns:
Column Phenomenex Aqua, length 150 mm, inner diameter 2 mm, filled with 125 A
C18-material, particle size 3 µm
Mobile phase A1 (4.14) Ammonium formate solution in water, c = 5 mmol/l
Mobile phase B1 (4.15) Ammonium formate solution in methanol, c = 5 mmol/l
Column temperature 40°C
Injection volume 3 µl, automatically diluted with 3 µl of mobile phase A1 during injection
procedure
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SIST-TS CEN/TS 17062:2017
CEN/TS 17062:2017 (E)
Table A.2 — Flow rate and elution gradient
Time Flow rate Mobile phase A Mobile phase B
1 1
min µl/min % %
0 100 100 0
3
...
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