SIST EN ISO 22892:2011

Soil quality - Guidelines for the identification of target compounds by gas chromatography and mass spectrometry (ISO 22892:2006)

ISO 22892:2006 gives criteria for gas chromatography and mass spectrometry (GC-MS) identification of target compounds in soil samples. ISO 22892:2006 is intended for use with standards developed for the determination of specific compounds. The identification criteria are based on the comparison of retention times followed by interpretation of the electron ionization mass spectra, or if necessary, additional mass spectrometric techniques and other relevant factors.

Bodenbeschaffenheit - Anleitungen für die Identifizierung von Zielverbindungen durch Gaschromatographie und Massenspektrometrie (ISO 22892:2006)

Diese Internationale Norm enthält Kriterien für die GC-MS-Identifizierung von Zielverbindungen in Bodenproben. Diese Internationale Norm kann mit solchen Normen angewendet werden, die für die Bestimmung von spezifischen Verbindungen entwickelt wurden. Die Identifizierungskriterien beruhen auf dem Vergleich der Retentionszeiten und der anschließenden Auswertung der Elektronenstoßmassenspektren oder, sofern erforderlich, zusätzlichen massenspektrometrischen Verfahren sowie weiteren relevanten Faktoren.
ANMERKUNG   Diese Internationale Norm ist auch für andere Umweltproben anwendbar.

Qualité du sol - Lignes directrices pour l'identification de composés cibles par chromatographie en phase gazeuse et spectrométrie de masse (ISO 22892:2006)

L'ISO 22892:2006 donne des critères pour l'identification par chromatographie en phase gazeuse et spectrométrie de masse (CG-SM) de composés cibles dans des échantillons de sol. Elle est destinée à être utilisée avec des normes élaborées pour permettre le dosage de composés spécifiques. Les critères d'identification sont fondés sur la comparaison des temps de rétention, puis sur l'interprétation des spectres de masse d'ionisation électronique ou, au besoin, sur des techniques de spectrométrie de masse supplémentaires et d'autres facteurs pertinents.

Kakovost tal - Smernice za identifikacijo ciljnih spojin s plinsko kromatografijo in masno spektrometrijo (ISO 22892:2006)

ISO 22892:2006 podaja kriterije za identifikacijo ciljnih spojin v vzorcih tal s plinsko kromatografijo in masno spektrometrijo (GC-MS). ISO 22892:2006 je namenjen uporabi s standardi, razvitimi za določevanje specifičnih spojin. Identifikacijski kriteriji temeljijo na primerjavi retencijskih časov, sledi interpretacija elektronskih ionizacijskih masnih spektrov ali po potrebi dodatne masne spektrometrične tehnike in drugi ustrezni dejavniki.

General Information

• Status: Published
• Public Enquiry End Date: 30-Apr-2011
• Publication Date: 17-Oct-2011
• ICS: 13.080.05 - Examination of soils in general
• Technical Committee: KAT - Soil quality
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 12-Sep-2011
• Due Date: 17-Nov-2011
• Completion Date: 18-Oct-2011
• Ref Project: EN ISO 22892:2011 - Soil quality - Guidelines for the identification of target compounds by gas chromatography and mass spectrometry (ISO 22892:2006)

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 22892:2011
01-november-2011
Kakovost tal - Smernice za identifikacijo ciljnih spojin s plinsko kromatografijo in
masno spektrometrijo (ISO 22892:2006)
Soil quality - Guidelines for the identification of target compounds by gas
chromatography and mass spectrometry (ISO 22892:2006)
Bodenbeschaffenheit - Anleitungen für die Identifizierung von Zielverbindungen durch
Gaschromatographie und Massenspektrometrie (ISO 22892:2006)
Qualité du sol - Lignes directrices pour l'identification de composés cibles par
chromatographie en phase gazeuse et spectrométrie de masse (ISO 22892:2006)
Ta slovenski standard je istoveten z: EN ISO 22892:2011
ICS:
13.080.05 Preiskava tal na splošno Examination of soils in
general
SIST EN ISO 22892:2011 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 22892:2011

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SIST EN ISO 22892:2011


EUROPEAN STANDARD
EN ISO 22892

NORME EUROPÉENNE

EUROPÄISCHE NORM
June 2011
ICS 13.080.05
English Version
Soil quality - Guidelines for the identification of target
compounds by gas chromatography and mass spectrometry
(ISO 22892:2006)
Qualité du sol - Lignes directrices pour l'identification de Bodenbeschaffenheit - Anleitungen für die Identifizierung
composés cibles par chromatographie en phase gazeuse von Zielverbindungen durch Gaschromatographie und
et spectrométrie de masse (ISO 22892:2006) Massenspektrometrie (ISO 22892:2006)
This European Standard was approved by CEN on 10 June 2011.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same
status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2011 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 22892:2011: E
worldwide for CEN national Members.

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SIST EN ISO 22892:2011
EN ISO 22892:2011 (E)
Contents Page
Foreword .3

2

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SIST EN ISO 22892:2011
EN ISO 22892:2011 (E)
Foreword
The text of ISO 22892:2006 has been prepared by Technical Committee ISO/TC 190 “Soil quality” of the
International Organization for Standardization (ISO) and has been taken over as EN ISO 22892:2011 by
Technical Committee CEN/TC 345 “Characterization of soils” the secretariat of which is held by NEN.
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by December 2011, and conflicting national standards shall be withdrawn
at the latest by December 2011.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: 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, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
Endorsement notice
The text of ISO 22892:2006 has been approved by CEN as a EN ISO 22892:2011 without any modification.

3

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SIST EN ISO 22892:2011

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SIST EN ISO 22892:2011


INTERNATIONAL ISO
STANDARD 22892
First edition
2006-02-01

Soil quality — Guidelines for the
identification of target compounds by gas
chromatography and mass spectrometry
Qualité du sol — Lignes directrices pour l'identification des composés
cibles par chromatographie en phase gazeuse et spectrométrie de
masse





Reference number
ISO 22892:2006(E)
©
ISO 2006

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SIST EN ISO 22892:2011
ISO 22892:2006(E)
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All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
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ii © ISO 2006 – All rights reserved

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SIST EN ISO 22892:2011
ISO 22892:2006(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope . 1
2 Principle. 1
3 Terms and definitions. 1
4 Apparatus . 2
5 Procedure . 3
5.1 Retention times . 3
5.2 Mass spectra, selection of diagnostic ions . 3
6 Qualification . 4
6.1 GC-MS procedure . 4
6.2 Additional information. 5
6.3 Reporting the presence of target compounds. 7
6.3.1 Identification. 7
6.3.2 Indication . 8
6.3.3 Absence of the target compound (< detection limit). 8
7 Test report . 8
Annex A (informative) Diagnostic ions to be used for identification using GC-MS . 9
Annex B (informative) Examples . 12
Annex C (informative) Examples of Spectra. 18
Bibliography . 20

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SIST EN ISO 22892:2011
ISO 22892:2006(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 22892 was prepared by Technical Committee ISO/TC 190, Soil quality, Subcommittee SC 3, Chemical
methods and soil characteristics.
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SIST EN ISO 22892:2011
ISO 22892:2006(E)
Introduction
In many analytical standards, use is made of gas chromatography (GC) in combination with mass
spectrometric (MS) detection. This detector is a powerful tool provided it is properly used. In this International
Standard, guidelines are given for the identification of target compounds. This International Standard can be
used in combination with specific analytical standards or in combination with any GC-MS procedure. The
result of the procedure described is: identified, indicated or absent.

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SIST EN ISO 22892:2011

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SIST EN ISO 22892:2011
INTERNATIONAL STANDARD ISO 22892:2006(E)

Soil quality — Guidelines for the identification of target
compounds by gas chromatography and mass spectrometry
1 Scope
This International Standard gives criteria for gas chromatography and mass spectrometry (GC-MS)
identification of target compounds in soil samples. This International Standard is intended for use with
standards developed for the determination of specific compounds. The identification criteria are based on the
comparison of retention times followed by interpretation of the electron ionization mass spectra, or if
necessary, additional mass spectrometric techniques and other relevant factors.
NOTE This International Standard is also applicable for other environmental samples.
2 Principle
A target compound is identified if the measured values meet the criteria specified in this International Standard
or in the standard in which the procedures are described to analyse the target compound. Criteria are based
on the relative retention times and the intensity of diagnostics ions selected in the scan mode and measured
in the selected ion mode (SIM), and other relevant factors. Additional information regarding diagnostic ions
from specific international standards on the analysis of the target compound can be used. The principle of
identification points is used.
3 Terms and definitions
For the purpose of this document, the following terms and definitions apply.
3.1
target compound
selected component, the presence or absence of which is being established
NOTE This definition also applies to derivatives of the original compound which are formed during an intentional
derivatization procedure or on-line derivatization.
3.2
standard compound
target compound with the highest possible purity, which can be used as a reference during the analysis
NOTE Any impurities should not have any influence on the mass spectrum of the standard compound.
3.3
retention time standard
compound that is added to the sample (or to the sample extract) and to the calibration standard solution, and
used to calculate the relative retention times of the target compounds
NOTE The retention time standard may be identical to the internal standard(s).
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SIST EN ISO 22892:2011
ISO 22892:2006(E)
3.4
relative retention time
ratio between the retention time of the target compound and the retention time of the retention time standard
3.5
lowest concentration for identification
lowest concentration of the target compound, which, if present in the sample, can be identified using the
identification criteria in this International Standard
NOTE 1 It requires that the selected diagnostic ion with the lowest intensity is still present in the mass spectrum with a
signal to noise ratio (S/N) higher than 3:1.
NOTE 2 This concentration is very dependent on the sensitivity of the instrument and on the performance
characteristics of the analytical method.
3.6
diagnostic ion
selected fragment ion, molecular ion or other characteristic ion from the mass spectrum of the target
compound with the highest possible specificity
3.7
identification point
result of mass spectrometric investigation or other investigations/information to identify a component in
environmental matrices
3.8
selected ion mode
SIM
measuring the intensity of selected diagnostic ions only
4 Apparatus
As this International Standard is complementary to other standards using GC-MS, it is assumed that the
instrumentation used meets the requirements of those standards and a detailed description is not within the
scope of this International Standard. Suitable quality assurance requirements are set out in ISO/IEC 17025.
Minimum requirements are:
Ionization mode: Electron ionization.
Electron energy: Depending on the application (usually 70 eV).
Mass range: Peaks (masses) with a S/N < 3 are not taken into consideration and the scan range is
limited to 35 (to avoid the measurement of oxygen and nitrogen) to the highest mass of
the target compound + 10 unified atomic mass units (u) in full scan measurements.
Scan rate: The scan rate should be 10 times the peak frequency with a minimum of 7 scans per
peak.
Scan mode: Cyclic, linear.
Full scan or selected ion monitoring.
Mass resolution: To be tuned on nominal resolution, the peak width at half-height of every tune mass
should not exceed 0,7 u.
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SIST EN ISO 22892:2011
ISO 22892:2006(E)
5 Procedure
5.1 Retention times
The relative retention time of the target compound shall be determined using a calibration standard solution
containing an appropriate number of internal standards. The use of internal standards is often prescribed in
the specific standard describing the determination of the target compound. The relative retention times
are calculated using the retention time standard(s). The calculated relative retention time shall have a value
below 2.
5.2 Mass spectra, selection of diagnostic ions
If available, three diagnostic ions shall be selected for each target compound. Their intensities I , I , I shall
1 2 3
be determined in the calibration standard solution (at least three injections) as the peak area or peak height of
the corresponding extracted ion current chromatograms. The relative intensities are calculated as the ratio of
the determined peak heights (or areas) and the peak height (or area) of the most intensive diagnostic ion.
Annex A gives a table of suitable diagnostic ions for a range of substances. Diagnostic ions may also be
specified in the standard method being used.
It is not always possible to obtain three diagnostic ions (for instance, polycyclic aromatic hydrocarbons). In
that case, select the available ions.
[3]
Diagnostic ions should have a high "uniqueness value" . It is suggested that:
⎯ high m/z values should be preferred due to their higher significance;
⎯ even mass fragments are preferred over odd ones;
⎯ if possible, the molecular ion should be selected as one of the diagnostic ions;
⎯ the intensity of diagnostic ions is preferably higher than 15 % in relation to the base peak in the spectrum;
⎯ if characteristic isotope clusters are present in the mass spectrum (e.g. chlorine), two diagnostic ions
should be selected from one isotope cluster. Isotopes can be very characteristic for complex compounds,
i.e. organotin;
⎯ if during the sample preparation, the target compounds have been derivatized with a reagent with low
+ + +
specificity, only one of the ions M and [M-der] should be selected as a diagnostic ion (M is the
molecular ion of the derivatized target compound);
⎯ in the selection of the diagnostic ions, possible column artefacts have to be taken into consideration,
avoiding corresponding masses (e.g. m/z 73, 207, 281);
The peak shape and retention time of all measured diagnostic ions shall be identical. Co-eluting substances
may influence the peak shape. As long as the peak of interest can be separately integrated, it may be used.
Criteria for the retention time are the peak maxima of the extracted ion current chromatograms.
Diagnostic ions are supposed to originate from the analyte under investigation only. This implies that
theoretically all diagnostic ions belonging to one and the same analyte have the same retention time. If the
retention time of one selected diagnostic ion differs from the retention times of the other diagnostic ions from
the same analyte, a co-eluting substance or a partly-separated substance giving the same mass may be
present. In this case, the particular diagnostic ion cannot be used.
The accuracy of the retention time depends on the number of scans within the chromatographic peak and
hence, on the scan rate. Because the scan rate is limited, small differences in the retention times of the
diagnostic ions should be allowed.
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SIST EN ISO 22892:2011
ISO 22892:2006(E)
A suitable criterion for the allowed difference in retention times of all diagnostic ions of an analyte shall not be
greater than 20 % of the peak width at half the peak height. Therefore, the differences in retention times of the
peak maxima of all the selected diagnostic ions in the extracted ion current chromatograms belonging to the
same analyte shall not be greater than 20 % of the peak width at half the peak height. For most analyses, this
means an acceptable difference of 1 s. These criteria apply for both the calibration standard solution and the
sample.
NOTE 1 MTBE and TAME have m/z 73 as diagnostic ion.
NOTE 2 Due to overloading, the ratios of the diagnostic ions can change.
6 Qualification
6.1 GC-MS procedure
The procedure to qualify a component consists of three steps (see the flow scheme in Figure 1).
⎯ Step 1: Gas-chromatographic result
The relative retention time shall fulfil the specified criteria (see 6.3, Step 1). Only if Step 1 is positive, can
Step 2 be made.
⎯ Step 2: Gathering identification points using analytical procedures
[1]
For qualification, the principle of identification points is used . Identification points can be obtained from
mass spectrometric data, but also using other analytical information.
⎯ Step 3: Gathering additional identification points using knowledge and interpretation of this knowledge
about the sample or sampling site.
Then the following classification can be obtained.
a) Identification (see 6.3.1)
The target compound is present in the analysed extract. At least three identification points are obtained.
b) Indication (see 6.3.2)
The target compound may be present. One or two identification points are obtained.
c) Absence (below the detection limit) (see 6.3.3)
No identification points are obtained using mass spectrometry.
First, the mass spectrometric results are evaluated. For every ion peak meeting the criteria given in 6.3,
Step 2, an identification point is obtained. Three identification points give a positive identification. If less then
three ion peaks are available [due to sensitivity (S/N < 3) or absence of fragments (PAH)], additional
identification points shall be gathered using additional evidence. Possibilities are given in Table 1 and also
explained in Annex B.
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SIST EN ISO 22892:2011
ISO 22892:2006(E)
Table 1 — Examples of number of identification points, provided criteria are met
Source Identification Remark
points
n
Diagnostic ion 1 Every ion S/N > 3
Absence of any other ions in full scan 1 Diagnostic ions in full scan S/N > 3
a
Column with other polarity 1 GC-criterion (extra retention time value)
Isotope dilution 1
Component spike/standard addition 1
Chromatographic pattern 1 i.e. PCB, PAH, dioxins
Other analytical techniques 1 Every other selective detector (i.e. ECD) or
technique (i.e. LC)
GC-MS (EI and CI; positive/negative) 3 1 (EI) + 2 (CI)
GC-MS-MS 4 1 precursor and 2 daughters (product ion)
HR-MS (high resolution MS) 2 Every ion S/N > 3
Expectation, plausibility, earlier investigations 1 See 6.2
NOTE More examples with different techniques are found in Reference [1].
a
Not valid for non-separated compounds (isomers) with the same mass (chrysene/triphenylene, m/p-xylene).

6.2 Additional information
Interpretation of environmental data is always a combination of data analyses, knowledge about the origin of
the sample, knowledge on the behaviour of contaminants and processes that occur or may occur. This is also
true for the interpretation of GC-MS analysis. As stated, a component is identified if 3 identification points are
obtained. If only 1 or 2 diagnostic ions are present, additional identification points are necessary. In this
International Standard, gathering additional identification points using analytical procedures is part of Step 2.
Using information about the sample, and interpretation of this information, takes place in Step 3. An extra
identification point is obtained if one or more of the following criteria is fulfilled.
NOTE Strictly taken, an identification point obtained in Step 3 is of another order than the identification points
obtained in Step 1 and Step 2. They are obtained by interpretation of additional non-analytical information. In this
International Standard, the term "identification point" (3.7) is used for the points obtained in all three steps.
Step 2: Gathering identification points using analytical procedures.
⎯ No other ions are visible in full scan mode and this is in agreement with the mass spectrum of the pure
component (for instance, PAH).
⎯ Identification is in agreement with the chromatographic pattern normally present or present on that site
(for instance, PCB or PAH).
⎯ For volatile compounds, the specificity of the mass fragments in combination with their retention time will
generally be sufficient. Their volatility corresponds to a low molecular mass, limiting the number of
possible false positive results: there are no low molecular mass compounds with the same retention time
on a GC column and also having similar mass spectra.
Step 3: Gathering additional identification points using knowledge and interpretation of this knowledge about
the sample or sampling site. If identification points are obtained using Step 3, this shall be reported.
⎯ The component is identified in earlier samples from the same site (for instance, if the sample under
investigation has a low concentration and one or two diagnostic ions have S/N < 3 following the
biodegradation.
⎯ From historical investigation, it was shown that presence of the component was expected.
⎯ Other samples from the same site give positive identification.
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SIST EN ISO 22892:2011
ISO 22892:2006(E)

a
A diagnostic ion must be present with S/N > 3
b
Only allowed if the missing ion has the smallest intensity and S/N < 3, otherwise not identified
Figure 1 — Flow scheme for the identification of a target compound using GC-MS
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SIST EN ISO 22892:2011
ISO 22892:2006(E)
6.3 Reporting the presence of target compounds
6.3.1 Identification
The analysed target compound is identified if:
Step 1
The relative or absolute retention time measured in the sample shall meet one of the following criteria, when
compared to the times measured in the last or following calibration standard solution:
⎯ absolute retention time shall not differ more than 1 s if the absolute retention time is less than 500 s; or,
⎯ relative retention time shall not differ more than ± 0,2 % relative if the absolute retention time is greater
than 500 s and less than 5 000 s; or,
⎯ absolute retention time shall not differ more than 6 s if the absolute retention time is greater than 5 000 s;
or,
⎯ as otherwise specified in the specific standard in use.
NOTE Absolute retention time criteria (1 s and 6 s) are added because the window of ± 0,2 % is too restrictive at the
very beginning of the chromatogram (components will not be identified), and at the end of the chromatogram not specific
enough (too many components will be identified).
Step 2
⎯ The relative intensities (relative to the diagnostic peak having the highest response in the calibration
standard solution) of all the selected diagnostic ions measured in the sample do not deviate by more than
± (0,1 × I + 10) % from the relative intensities determined in the calibration standard solution.
std
⎯ I is the relative intensity of the diagnostic ion in the calibration standard solution.
std
Every diagnostic ion gives 1 identification point. At least 3 points must be obtained in order to achieve
identification.
EXAMPLE 1 Identification with GC-MS (three diagnostic ions).
Three selected diagnostic ions satisfy the criteria for identification, as also explained in Annex B.
A total of 3 identification points is obtained.
Step 3
Extra identification points can be gathered as described in Table 1 and Annex B.
EXAMPLE 2 Identification with GC-MS and additional evidence (low concentration).
The most sensitive diagnostic ion is present (S/N > 3) 1 identification point
Column with other polarity (Step 1) 1 identification point
Expected value 1 identification point
EXAMPLE 3 Identification with GC-MS and additional evidence (only 1 diagnostic ion, for instance PAH).
Diagnostic ion with S/N > 3 is present 1 identification point
Pattern of PAH recognized 1 identification point
Result of LC-FLD 1 identification point
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SIST EN ISO 22892:2011
ISO 22892:2006(E)
6.3.2 Indication
There is an indication for the presence of the analysed target compound in the sample if:
Step 1
The criteria given in 6.3.1 Step 1 are met.
Step 2 and Step 3
Only one or two identification points are obtained. At least one must be based on the GC-MS data.
6.3.3
...