Bsi bs en 01948 4 2010 + a1 2013

EN 1948-1:2006, Stationary source emissions - Determination of the mass concentration of PCDDs/PCDFs and dioxin-like PCBs - Part 1: Sampling of PCDDs/PCDFs EN 1948-2:2006, Stationary s

BSI Standards Publication

Stationary source emissions

— Determination of the mass concentration of PCDDs/PCDFs and dioxin-like PCBs

Part 4: Sampling and analysis of dioxin-like PCBs

National foreword

This British Standard is the UK implementation of EN 1948-4:2010+A1:2013

It supersedes BS EN 1948-4:2010 which is withdrawn

The start and finish of text introduced or altered by amendment is indicated

in the text by tags Tags indicating changes to CEN text carry the number of the CEN amendment For example, text altered by CEN amendment A1 is indicated by 

The UK participation in its preparation was entrusted by Technical Committee EH/2, Air quality, to Subcommittee EH/2/1, Stationary source emission

A list of organizations represented on this subcommittee can be obtained on request to its secretary

This publication does not purport to include all the necessary provisions

of a contract Users are responsible for its correct application

© The British Standards Institution 2014

Published by BSI Standards Limited 2014ISBN 978 0 580 81791 5

Amendments/corrigenda issued since publication

28 February 2014 Implementation of CEN amendment A1:2013

NORME EUROPÉENNE

EUROPÄISCHE NORM

December 2013

English Version Stationary source emissions - Determination of the mass concentration of PCDDs/PCDFs and dioxin-like PCBs - Part 4:

Sampling and analysis of dioxin-like PCBs

Émissions de sources fixes - Détermination de la

concentration massique en PCDD/PCDF et PCB de type

dioxine - Partie 4: Prélèvement et analyse des PCB de type

dioxine

Emissionen aus stationären Quellen - Bestimmung der Massenkonzentration von PCDD/PCDF und dioxin- ähnlichen PCB - Teil 4: Probenahme und Analyse dioxin-

ähnlicher PCB

This European Standard was approved by CEN on 28 August 2010 and includes Amendment 1 approved by CEN on 23 October 2013 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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,

Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom

EUROPEAN COMMITTEE FOR STANDARDIZATION

C O M IT É E U R OP É E N D E N O RM A LIS A T IO N EURO PÄ ISC HES KOM ITE E FÜR NORM UNG

CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels

© 2013 CEN All rights of exploitation in any form and by any means reserved

worldwide for CEN national Members Ref No EN 1948-4:2010+A1:2013 E

Contents Page

Foreword 4

Introduction 5

1 Scope 6

2 Normative references 7

3 Terms and definitions 7

4 Symbols and abbreviations 10

4.1 General 10

4.2 Polychlorinated biphenyls 11

5 Principle of the measurement procedure 11

6 Device, materials and 13 C 12 -labelled standards 12

6.1 Device and materials 12

6.2 13 C 12 -labelled standards 12

7 Safety measures 13

8 Measurement procedure 13

8.1 Sampling 13

8.2 Extraction 13

8.3 Clean-up 14

8.4 Final concentration of the sample extracts 15

8.5 Addition of recovery standards 15

8.6 Principle of identification and quantification 15

8.7 Calibration of the HRGC/HRMS 16

8.8 Quantification of HRGC/HRMS results 18

8.8.1 Quantification of the sample 18

8.8.2 Calculation of the recovery rates of the extraction standards 18

8.8.3 Calculation of the recovery rates of the sampling standards 19

8.9 Calculation of the measurement results 20

8.10 Analytical report 20

9 Method validation 21

9.1 General 21

9.2 Validation of sampling 22

9.3 Validation of Analytical Extraction and Clean-up 22

9.3.1 Extraction 22

9.3.2 Clean-up 22

10 Quality control requirements for the measurement 22

10.1 Use of a validated method 22

10.2 Use of 13 C 12 -labelled standards 23

10.3 Minimum requirements for sampling 23

10.4 Minimum requirements for extraction and clean-up 24

10.5 Minimum requirements for identification of PCB congeners 24

10.6 Minimum requirements for quantification 25

11 Quality assurance criteria for extraction/clean-up/quantification procedure blanks 26

11.1 Analytical blank 26

11.2 HRGC/HRMS blank 26

Contents Page

Foreword 4

Introduction 5

1 Scope 6

2 Normative references 7

3 Terms and definitions 7

4 Symbols and abbreviations 10

4.1 General 10

4.2 Polychlorinated biphenyls 11

5 Principle of the measurement procedure 11

6 Device, materials and 13 C 12 -labelled standards 12

6.1 Device and materials 12

6.2 13 C 12 -labelled standards 12

7 Safety measures 13

8 Measurement procedure 13

8.1 Sampling 13

8.2 Extraction 13

8.3 Clean-up 14

8.4 Final concentration of the sample extracts 15

8.5 Addition of recovery standards 15

8.6 Principle of identification and quantification 15

8.7 Calibration of the HRGC/HRMS 16

8.8 Quantification of HRGC/HRMS results 18

8.8.1 Quantification of the sample 18

8.8.2 Calculation of the recovery rates of the extraction standards 18

8.8.3 Calculation of the recovery rates of the sampling standards 19

8.9 Calculation of the measurement results 20

8.10 Analytical report 20

9 Method validation 21

9.1 General 21

9.2 Validation of sampling 22

9.3 Validation of Analytical Extraction and Clean-up 22

9.3.1 Extraction 22

9.3.2 Clean-up 22

10 Quality control requirements for the measurement 22

10.1 Use of a validated method 22

10.2 Use of 13 C 12 -labelled standards 23

10.3 Minimum requirements for sampling 23

10.4 Minimum requirements for extraction and clean-up 24

10.5 Minimum requirements for identification of PCB congeners 24

10.6 Minimum requirements for quantification 25

11 Quality assurance criteria for extraction/clean-up/quantification procedure blanks 26

11.1 Analytical blank 26

11.2 HRGC/HRMS blank 26

12 Performance characteristics 27

12.1 General 27

12.2 Results of the validation campaign 27

13 Interferences (informative) 28

Annex A (informative) Toxicity and toxic equivalency 30

Annex B (informative) Examples of extraction and clean-up procedures 32

B.1 Example for clean-up of PCB and the separation from PCDD/PCDFs 32

B.1.1 General 32

B.1.2 Chromatography column I 34

B.1.3 Chromatography column II 34

B.1.4 Additional clean-up I 34

B.1.5 Additional clean-up II 35

B.1.5.1 General 35

B.1.5.2 Carbon Column 35

B.1.5.3 Preparation 35

B.1.6 Addition of the recovery standard 35

B.1.7 HRGC/HRMS-analysis 35

B.2 Description of extraction and clean-up procedures used in the validation campaign 41

Annex C (informative) Evaluation of the performance characteristics 43

C.1 General 43

C.2 Interlaboratory comparison study of the analytical method 43

C.3 Accuracy 44

C.4 Limits of detection (LOD) and limits of quantification (LOQ) 46

C.5 Recovery 48

C.6 Breakthrough 49

Annex D (informative) Recommendations for measuring high concentrations of dioxin-like PCBs 51

Annex E (informative) Possible interferences in dioxin-like PCB analysis 52

Annex F (informative) Measurement of the marker PCBs 28, 52, 101, 138, 153, and 180 in addition to the 12 dioxin-like PCBs 56

Annex G (informative) Measurement of hexachlorobenzene (HCB) 59

Annex H (informative) Significant technical changes 60

Annex ZA (informative) Relationship between this European Standard and the essential requirements of EU Directives 61

Bibliography 62

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 This document includes Amendment 1 approved by CEN on 21 October 2013

This document supersedes EN 1948-4:2010

Annex H provides details of significant technical changes between this European Standard and the previous document CEN/TS 1948-4:2007

This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association, and supports essential requirements of EU Directive

For relationship with EU Directive(s), see informative Annex ZA, which is an integral part of this document The start and finish of text introduced or altered by amendment is indicated by tags 

EN 1948 consists of several parts dealing with the determination of the mass concentration of PCDDs, PCDFs and PCBs in stationary source emissions:

— Part 1: Sampling of PCDDs/PCDFs

— Part 2: Extraction and clean-up of PCDDs/PCDFs

— Part 3: Identification and quantification of PCDDs/PCDFs

— Part 4: Sampling and analysis of dioxin-like PCBs

The first three parts are necessary for the performance of the PCDD/PCDF measurements In addition this document EN 1948-4 describes the sampling, extraction and analyses of dioxin-like PCBs and requires references to EN 1948-1, −2, −3

The precision and the performance characteristics of the measurement of PCBs were determined between

2006 and 2008 in a comparison and validation trial at both a waste incinerator and a shredder plant sponsored

by the European Commission and the European Free Trade Association The basic requirements of the determination of PCBs were first published as CEN/TS 1948-4, which served as a basis for these mandated validation measurements This document EN 1948-4 additionally includes important guidance for sampling and analysis over a broad concentration range gained during the mandated validation measurements

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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom

Foreword

This document (EN 1948-4:2010+A1:2013) has been prepared by Technical Committee CEN/TC 264 “Air

quality”, the secretariat of which is held by DIN

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 June 2014, and conflicting national standards shall be withdrawn at

the latest by June 2014

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

This document includes Amendment 1 approved by CEN on 21 October 2013

This document supersedes EN 1948-4:2010

Annex H provides details of significant technical changes between this European Standard and the previous

document CEN/TS 1948-4:2007

This document has been prepared under a mandate given to CEN by the European Commission and the

European Free Trade Association, and supports essential requirements of EU Directive

For relationship with EU Directive(s), see informative Annex ZA, which is an integral part of this document

The start and finish of text introduced or altered by amendment is indicated by tags 

EN 1948 consists of several parts dealing with the determination of the mass concentration of PCDDs, PCDFs

and PCBs in stationary source emissions:

— Part 1: Sampling of PCDDs/PCDFs

— Part 2: Extraction and clean-up of PCDDs/PCDFs

— Part 3: Identification and quantification of PCDDs/PCDFs

— Part 4: Sampling and analysis of dioxin-like PCBs

The first three parts are necessary for the performance of the PCDD/PCDF measurements In addition this

document EN 1948-4 describes the sampling, extraction and analyses of dioxin-like PCBs and requires

references to EN 1948-1, −2, −3

The precision and the performance characteristics of the measurement of PCBs were determined between

2006 and 2008 in a comparison and validation trial at both a waste incinerator and a shredder plant sponsored

by the European Commission and the European Free Trade Association The basic requirements of the

determination of PCBs were first published as CEN/TS 1948-4, which served as a basis for these mandated

validation measurements This document EN 1948-4 additionally includes important guidance for sampling

and analysis over a broad concentration range gained during the mandated validation measurements

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, Former Yugoslav Republic of Macedonia, France, Germany, Greece,

Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,

Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom

Introduction

Polychlorinated biphenyls (PCBs) are a group of chlorinated aromatic compounds similar in structure to

polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) which consist of 209

individual substances (see Figure 1 for the basic structure)

PCBs have been produced intentionally over approximately 50 years until the end of the 1990s with different uses in open and closed systems, e.g as electrical insulators or dielectric fluids in capacitors and transformers, specialised hydraulic fluids, as a plasticiser in sealing material, etc Worldwide, more than one million tons of PCBs were produced

PCBs as well as PCDD/PCDF are emitted from thermal and other processes PCB can contribute to the Total WHO-TEQ as reported for Germany [1]; [2], Great Britain [3], Poland [4], Spain [5], Japan [6]; [7], Korea [8]

In 1997 a group of experts of the World Health Organisation (WHO) defined toxicity equivalent factors (TEFs) for PCDDs/PCDFs and 12 PCBs, known as dioxin-like PCBs [9, 10] (see Annex A) These 12 dioxin-like PCBs consist of four non-ortho PCBs and eight mono-ortho PCBs (no or only one chlorine atoms in 2-, 2’-, 6- and 6’-position), having a planar or mostly planar structure, see Figure 1 In the meanwhile these toxicity equivalent factors were revised (see Annex A)

This document deals with the determination of these dioxin-like PCBs in emissions from stationary sources

Additionally informative annexes are provided, describing the analyses of the marker PCBs and hexachlorobenzene (HCB) in the same sample (Annex F and Annex G)

Only skilled operators who are trained in handling highly toxic compounds should apply this document

Figure 1 —Structure of PCB

1 Scope

This European Standard specifies sampling from stationary sources, extraction, clean-up, identification and quantification procedures of the dioxin-like PCBs The procedure described lays down requirements to measure the PCB congeners given in Annex A (see Table A.1) It is applicable to the 12 non- and mono-ortho PCB designated by the WHO It is optimised to measure PCB concentrations of about 0,01 ng WHO-TEQPCB/m3

In addition to the 12 non- and mono-ortho-PCB the present document is also applicable to measure further PCB-congeners like the “marker PCB” 28, 52, 101, 138, 153, 180 (see Annex F)

This document specifies a framework of quality control requirements for any PCB sampling, extraction,

clean-up, identification and quantification methods to be applied

As a result of their similar chemical behaviour PCBs, as shown in the validation campaign, can be sampled from stationary sources together with the PCDDs/PCDFs Therefore, it is possible to measure PCBs together with PCDDs/PCDFs by applying EN 1948-1, −2, −3 and −4 The complete sampling procedure is described in

EN 1948-1 Each of the three sampling methods of EN 1948-1 can be combined with the methods described

in this document to complete the measurement procedure EN 1948-1 is an integral part of the complete measurement procedure and is necessary for the determination of PCBs

The analyses of the following PCB congeners is described in this European Standard and is validated in the validation campaign:

1 Scope

This European Standard specifies sampling from stationary sources, extraction, clean-up, identification and

quantification procedures of the dioxin-like PCBs The procedure described lays down requirements to

measure the PCB congeners given in Annex A (see Table A.1) It is applicable to the 12 non- and mono-ortho

PCB designated by the WHO It is optimised to measure PCB concentrations of about 0,01 ng

WHO-TEQPCB/m3

In addition to the 12 non- and mono-ortho-PCB the present document is also applicable to measure further

PCB-congeners like the “marker PCB” 28, 52, 101, 138, 153, 180 (see Annex F)

This document specifies a framework of quality control requirements for any PCB sampling, extraction,

clean-up, identification and quantification methods to be applied

As a result of their similar chemical behaviour PCBs, as shown in the validation campaign, can be sampled

from stationary sources together with the PCDDs/PCDFs Therefore, it is possible to measure PCBs together

with PCDDs/PCDFs by applying EN 1948-1, −2, −3 and −4 The complete sampling procedure is described in

EN 1948-1 Each of the three sampling methods of EN 1948-1 can be combined with the methods described

in this document to complete the measurement procedure EN 1948-1 is an integral part of the complete

measurement procedure and is necessary for the determination of PCBs

The analyses of the following PCB congeners is described in this European Standard and is validated in the

2 Normative references

The following referenced documents are indispensable for the application of this document For dated references, only the edition cited applies For undated references, the latest edition of the referenced document (including any amendments) applies

EN 1948-1:2006, Stationary source emissions - Determination of the mass concentration of PCDDs/PCDFs

and dioxin-like PCBs - Part 1: Sampling of PCDDs/PCDFs

EN 1948-2:2006, Stationary source emissions - Determination of the mass concentration of PCDDs/PCDFs

and dioxin-like PCBs - Part 2: Extraction and clean-up of PCDDs/PCDFs

EN 1948-3:2006, Stationary source emissions - Determination of the mass concentration of PCDDs/PCDFs

and dioxin-like PCBs - Part 3: Identification and quantification of PCDDs/PCDFs

EN 13284-1:2001, Stationary source emissions - Determination of low range mass concentration of dust –

Part 1: Manual gravimetric method

3 Terms and definitions

For the purposes of this document, the terms and definitions given in EN 1948-1:2006, EN 1948-2:2006,

EN 1948-3:2006 and the following apply

3.1 analytical blank value

value determined by a blank sample covering the complete analytical procedure including extraction,

clean-up, identification and quantification including all the relevant reagents and materials

3.2 congener

any one of the 209 individual PCBs

3.3 dioxin-like PCB WHO-PCB

non- and mono-ortho PCB with an affinity to the Ah-receptor, showing similar toxic effects as the substituted PCDDs/PCDFs according to WHO [9]

2,3,7,8-3.4 extraction standard quantification standard

13C12-labelled PCBs, added before extraction and used for calculating results

3.5

field blank value

value determined by a blank sample covering a specific procedure to ensure that no significant contamination has occurred during all steps of measurement and to check that the operator can achieve a quantification level suitable for the task

3.6

I-TEF

international toxic equivalent factor defined by NATO/CCMS in 1988 [11]

NOTE For detailed description, see EN 1948–1:2006, Annex A

3.7

I-TEQ

international toxic equivalent obtained by weighting the mass determined with the corresponding I-TEF

NOTE For a detailed description, see EN 1948–1:2006, Annex A

[Adapted from EN ISO 9169:2006, 2.2.10 [12]]

NOTE 2 The measurement value can be distinguished from the analytical blank value with a confidence of 99 % The

limit of detection is expressed as the mean analytical blank value (bave) plus three times the standard deviation of the

analytical blank (sb)

b ave s

b

where

LOD is the detection limit;

bave is the mean analytical blank value;

sb is standard deviation of the analytical blank

NOTE 3 In this document the limit of detection should preferably be calculated from the analytical blank bave If this is not possible, the limit of detection can be calculated from the signal to noise ratio according to 8.1 of EN 1948–3:2006 (resp 10.5 of this document)

3.5

field blank value

value determined by a blank sample covering a specific procedure to ensure that no significant contamination

has occurred during all steps of measurement and to check that the operator can achieve a quantification

level suitable for the task

3.6

I-TEF

international toxic equivalent factor defined by NATO/CCMS in 1988 [11]

NOTE For detailed description, see EN 1948–1:2006, Annex A

3.7

I-TEQ

international toxic equivalent obtained by weighting the mass determined with the corresponding I-TEF

NOTE For a detailed description, see EN 1948–1:2006, Annex A

3.8

isokinetic sampling

sampling at a flow rate such that the velocity and direction of the gas entering the sampling nozzle are the

same as the velocity and direction of the gas in the duct at the sampling point

NOTE 1 The detection limit, also referred to as capability of detection, is defined by reference to the applicable basic

state But it may be different from “zero”, for instance for oxygen measurement as well as when gas chromatographs are

used

[Adapted from EN ISO 9169:2006, 2.2.10 [12]]

NOTE 2 The measurement value can be distinguished from the analytical blank value with a confidence of 99 % The

limit of detection is expressed as the mean analytical blank value (bave) plus three times the standard deviation of the

analytical blank (sb)

b ave s

b

where

LOD is the detection limit;

bave is the mean analytical blank value;

sb is standard deviation of the analytical blank

NOTE 3 In this document the limit of detection should preferably be calculated from the analytical blank bave If this is

not possible, the limit of detection can be calculated from the signal to noise ratio according to 8.1 of EN 1948–3:2006

(resp 10.5 of this document)

3.11 limit of quantification LOQ

limit above which a quantification of the measurand is possible, expressed as the mean analytical blank value plus five to ten times the standard deviation of the analytical blank

NOTE 1 The factor F depends on the accepted measurement uncertainty

b ave F s b

where

LOQ is the quantification limit;

bave is the mean analytical blank value;

sb is standard deviation of the analytical blank

NOTE 2 In this document the limit of quantification should preferably be calculated from the analytical blank bave If this

is not possible, the limit of quantification can be calculated from the signal to noise ratio according to 8.1 of

EN 1948–3:2006 or see 10.5 of this document using the requirement of 8.3, e) of EN 1948–3:2006 or 10.6, d) of this document

NOTE 3 In practice, the Factor F = 10 corresponds to a reasonable measurement uncertainty of approximately 20 %

3.12 marker PCBs

the six PCBs: 28, 52, 101, 138, 153, 180

3.13 PCB isomers

PCBs with identical chemical composition but different structure

3.14 recovery standard

13C12-labelled PCBs, added before injection into the GC

3.15 sampling standard

13C12-labelled PCBs, added before sampling

3.16 spiking

addition of 13C12-labelled PCB standards

3.17 WHO-TEF

toxic equivalent factor first proposed by WHO in 1997 [9; 10]

NOTE For detailed description, see Annex A

3.18 WHO-TEQ

toxic equivalent obtained by multiplying the mass determined with the corresponding WHO-TEF including PCDDs, PCDFs and PCBs

NOTE 1 For detailed description, see Annex A

NOTE 2 WHO-TEQPCB, WHO-TEQPCDD/PCDF and WHO-TEQPCDD/PCDF/PCB should be used to distinguish different compound classes In this document WHO-TEQPCDD/PCDF/PCB is also defined as Total WHO-TEQ

4 Symbols and abbreviations

NOTE 2 WHO-TEQPCB, WHO-TEQPCDD/PCDF and WHO-TEQPCDD/PCDF/PCB should be used to distinguish

different compound classes In this document WHO-TEQPCDD/PCDF/PCB is also defined as Total WHO-TEQ

4 Symbols and abbreviations

5 Principle of the measurement procedure

Gas is sampled in the duct or stack according to the methods described in EN 1948-1 taking into account the requirements of isokinetic sampling according to EN 13284-1 PCBs in the gas phase and adsorbed on particles are collected in the sampling train together with the PCDDs/PCDFs Minimum requirements for PCDD/PCDF sampling are described in EN 1948-1 and have also to be met for PCB sampling There is the choice between three different sampling systems:

— filter/condenser method;

— dilution method;

— cooled probe method

13C12-labelled PCB congeners are added at different stages of the whole method (before sampling, extraction and HRGC/HRMS-measurement) Spiking with 13C12-labelled PCBs according to 6.2 before sampling is necessary to determine the sampling recovery rate of the PCB congeners Losses during extraction and clean-up are detected and compensated by using these added congeners as internal extraction standards for quantification together with recovery standards which are added just before the HRGC/HRMS analysis

For the determination of PCBs it is useful to separate them from PCDDs/PCDFs and vice versa (interferences see Annex E)

The main purpose of the clean-up procedure of the raw sample extract is removal of sample matrix components, which can overload the separation method, disturb the quantification or severely impact the performance of the identification and quantification method Furthermore, enrichment of the analytes in the final sample extract is achieved Extraction procedures are normally based on soxhlet extraction of filters and adsorbents and liquid extraction of the condensate Sample clean-up is usually carried out by multi-column liquid chromatographic techniques using different adsorbents

The method specified in this document is based on using gas chromatography/mass spectrometry combined with the isotope dilution technique to enable the separation, detection and quantification of PCB in the extracts

of emission samples These extracts are prepared in accordance with EN 1948-2 and contain at least one of the recovery standards mentioned in Table 1 The combination of gas chromatography and mass spectrometry enables the differentiation of 12 dioxin-like PCB congeners and marker PCB congeners by either retention time and/or mass

6 Device, materials and 13C12-labelled standards

6.1 Device and materials

For determining dioxin-like PCBs in emission samples the same devices and materials for sampling, extraction, clean-up, identification and quantification may be used as for determining PCDDs/PCDFs For a description, see EN 1948-1, EN 1948-2 and EN 1948-3 The reagents shall be of high purity to meet the criteria of blank analysis to have a low PCB and PCDD/PCDF background concentration

6.2 13C12-labelled standards

The sampling standards (see Table 1) shall be added to the different sampling media before sampling and the extraction standards shall be added to the samples before extraction (see EN 1948-1) These 13C12-labelled congeners behave in the same way as the native PCBs during sampling and clean-up due to their similar chemical and physical properties The sampling standards are only used to verify the sampling quality

by determining their recovery rates versus extraction standard The extraction standards are used for quantification The recovery standards are added just before injection to measure the recovery rates of the extraction standards Table 1 shows a selection of available 13C12-labelled PCBs suitable as recovery standards At least one shall be added for each dioxin-like PCB containing fraction The quantities of the 13C12-labelled congeners to be added per sample for sampling at a PCB concentration level of 0,01 ng WHO-TEQPCB/m3 and 10 m3 sampling volume (dry gas) are given in Table 1 If a considerably higher mass of native PCBs is expected in the sample, the masses of the 13C12-labelled standards to be added shall be enhanced accordingly taking into account the calibration range

Table 1 — 13 C 12 -labelled PCBs congeners to be added to the sample at different stages of the procedure for measurement of about 0,01 ng WHO-TEQPCB/m 3 assuming 10 m 3 of sampling volume

Solution:

Total volume in microlitres:

(e.g toluene, n-nonane)

6 Device, materials and 13C12-labelled standards

6.1 Device and materials

For determining dioxin-like PCBs in emission samples the same devices and materials for sampling,

extraction, clean-up, identification and quantification may be used as for determining PCDDs/PCDFs For a

description, see EN 1948-1, EN 1948-2 and EN 1948-3 The reagents shall be of high purity to meet the

criteria of blank analysis to have a low PCB and PCDD/PCDF background concentration

6.2 13C12-labelled standards

The sampling standards (see Table 1) shall be added to the different sampling media before sampling and the

extraction standards shall be added to the samples before extraction (see EN 1948-1) These 13C12

-labelled congeners behave in the same way as the native PCBs during sampling and clean-up due to their

similar chemical and physical properties The sampling standards are only used to verify the sampling quality

by determining their recovery rates versus extraction standard The extraction standards are used for

quantification The recovery standards are added just before injection to measure the recovery rates of the

extraction standards Table 1 shows a selection of available 13C12-labelled PCBs suitable as recovery

standards At least one shall be added for each dioxin-like PCB containing fraction The quantities of the 13C12

-labelled congeners to be added per sample for sampling at a PCB concentration level of 0,01 ng

WHO-TEQPCB/m3 and 10 m3 sampling volume (dry gas) are given in Table 1 If a considerably higher mass of native

PCBs is expected in the sample, the masses of the 13C12-labelled standards to be added shall be enhanced

accordingly taking into account the calibration range

Table 1 — 13 C 12 -labelled PCBs congeners to be added to the sample at different stages of the

procedure for measurement of about 0,01 ng WHO-TEQPCB/m 3 assuming 10 m 3 of sampling volume

Solution:

Total volume in microlitres:

(e.g toluene, n-nonane)

Total volume in microlitres:

(e.g toluene, n-nonane)

b Sampling Standards: Attention should be paid to possible co-elution problems of PCB 127 and

PCB 105 on certain commercially available columns If the co-elution problems cannot be avoided, the sampling standard PCB 127 may be omitted.

7 Safety measures

All relevant national safety regulations shall be observed The dioxin-like PCBs as well as the 2,3,7,8-chlorine substituted PCDDs/PCDFs, which can usually be present in emission samples together with PCBs, are amongst the most toxic chemicals All work with PCBs and PCDDs/PCDFs therefore requires the utmost care; the national safety measures which correspond to those for toxic substances shall be strictly adhered to

8 Measurement procedure

8.1 Sampling

The sampling and storage shall be performed according to EN 1948-1

The sampling train is spiked with 13C12-labelled PCBs (see Table 1) as described for PCDD/PCDF in

EN 1948-1

For sample storage the use of screw caps with aluminium-lined seals is recommended to avoid losses Alternatively the use of non-greased glass ground necks is recommended If using plastic sealings, losses have to be expected due to adsorption on the sealing materials

8.2 Extraction

Before extraction the extraction standards shall be added to the sample following EN 1948-2 Pre-treatment of all sampled particles with hydrochloric acid shall be part of any extraction procedure (examples of procedures are given in Annex A of EN 1948-2:2006, see also [13]) The extraction procedure is carried out using the following materials and techniques Detailed descriptions of some procedures are given in Annex A of

EN 1948-2:2006 Other methods can also be used but shall be of proven equal performance to the techniques below:

a) For particle collecting media (glass fibre filters, thimbles, glass wool, etc.) a Soxhlet extraction with toluene or a comparable method shall be performed

b) For solid adsorbents (Polyurethane foam, XAD-2) a Soxhlet extraction for 20 h with toluene or comparable validated method shall be performed (Water shall be removed, e.g via a Dean-Stark water separator or by sodium sulphate.)

c) For aqueous liquids (condensate and bubbler/impinger solution) a liquid/liquid extraction with toluene or dichloromethane shall be performed The water/toluene volume ratio should not be greater than 20:1 Three consecutive extractions shall be carried out

d) The inner surfaces of tubes, vessels or other parts of the sampling device in contact with the sample shall

be rinsed with a water-miscible solvent (acetone, methanol) followed by toluene Reflux boiling with toluene is an alternative for the second rinsing step

e) When sampling with flow division is performed, the filter part and the condenser/adsorber part may be analyzed separately The measured concentrations shall be added at the final stage of calculation

f) Alternatively an aliquot of the filter extract, corresponding to the proportion of side stream to main stream gas volume, is combined for analysis with the condenser/adsorber part In this case, the quantity of extraction standard solution added to the filter is increased in proportion to the ratio of main stream to side stream gas volume

g) If coke or activated carbon is used in the gas cleaning system of the incinerator suitable methods, including freeze drying or Dean-Stark extraction or the addition of water miscible solvents to the extraction medium, shall be taken to remove water Attention shall be paid to the method validation of this step

After extraction, the organic solvents containing water shall be dried before the concentration procedure After combination of all extraction and rinsing solutions any volume reduction shall be carefully carried out to avoid evaporation losses of PCBs In case evaporation to nearly dryness is necessary, use of a small amount (e.g

50 µl) of a keeper (usually a high-boiling solvent such as tetradecane) is strongly recommended

8.3 Clean-up

Clean-up methods shall prepare the sample extract in an appropriate manner for subsequent quantitative determination (see also 8.8) Clean-up procedures have to concentrate PCBs in the extracts and to remove interfering matrix components present in the raw extract

Proven clean-up procedures shall be used normally containing two or more of the following techniques which can be combined in different orders A detailed description of some of the procedures is given in Annex B Other methods can also be used but shall be proven to be of equal performance to the techniques described below:

a) Gel permeation chromatography

The interesting molecular weight range for PCBs of 200 g/mol to 500 g/mol can be isolated from larger molecules and polymers which might overload other clean-up methods

b) Multilayer column liquid chromatography

Silica with different activity grades and surface modifications Compounds with different chemical properties than PCBs can be removed If sulphuric acid treatment of the sample extract is carried out, it has to be checked that losses of PCBs do not occur due to the formed carboniferous surfaces

c) Column adsorption chromatography using activated carbon

a) For particle collecting media (glass fibre filters, thimbles, glass wool, etc.) a Soxhlet extraction with

toluene or a comparable method shall be performed

b) For solid adsorbents (Polyurethane foam, XAD-2) a Soxhlet extraction for 20 h with toluene or

comparable validated method shall be performed (Water shall be removed, e.g via a Dean-Stark water

separator or by sodium sulphate.)

c) For aqueous liquids (condensate and bubbler/impinger solution) a liquid/liquid extraction with toluene or

dichloromethane shall be performed The water/toluene volume ratio should not be greater than 20:1

Three consecutive extractions shall be carried out

d) The inner surfaces of tubes, vessels or other parts of the sampling device in contact with the sample shall

be rinsed with a water-miscible solvent (acetone, methanol) followed by toluene Reflux boiling with

toluene is an alternative for the second rinsing step

e) When sampling with flow division is performed, the filter part and the condenser/adsorber part may be

analyzed separately The measured concentrations shall be added at the final stage of calculation

f) Alternatively an aliquot of the filter extract, corresponding to the proportion of side stream to main stream

gas volume, is combined for analysis with the condenser/adsorber part In this case, the quantity of

extraction standard solution added to the filter is increased in proportion to the ratio of main stream to

side stream gas volume

g) If coke or activated carbon is used in the gas cleaning system of the incinerator suitable methods,

including freeze drying or Dean-Stark extraction or the addition of water miscible solvents to the

extraction medium, shall be taken to remove water Attention shall be paid to the method validation of this

step

After extraction, the organic solvents containing water shall be dried before the concentration procedure After

combination of all extraction and rinsing solutions any volume reduction shall be carefully carried out to avoid

evaporation losses of PCBs In case evaporation to nearly dryness is necessary, use of a small amount (e.g

50 µl) of a keeper (usually a high-boiling solvent such as tetradecane) is strongly recommended

8.3 Clean-up

Clean-up methods shall prepare the sample extract in an appropriate manner for subsequent quantitative

determination (see also 8.8) Clean-up procedures have to concentrate PCBs in the extracts and to remove

interfering matrix components present in the raw extract

Proven clean-up procedures shall be used normally containing two or more of the following techniques which

can be combined in different orders A detailed description of some of the procedures is given in Annex B

Other methods can also be used but shall be proven to be of equal performance to the techniques described

below:

a) Gel permeation chromatography

The interesting molecular weight range for PCBs of 200 g/mol to 500 g/mol can be isolated from larger

molecules and polymers which might overload other clean-up methods

b) Multilayer column liquid chromatography

Silica with different activity grades and surface modifications Compounds with different chemical

properties than PCBs can be removed If sulphuric acid treatment of the sample extract is carried out, it

has to be checked that losses of PCBs do not occur due to the formed carboniferous surfaces

c) Column adsorption chromatography using activated carbon

Non-ortho PCBs' molecules are separated from mono- and di-ortho PCBs

d) Column liquid chromatography on alumina of different activity grade and acidity/basicity Interfering compounds with small differences in polarity or structure compared to PCBs can be removed

8.4 Final concentration of the sample extracts

To achieve sufficient quantification limits, the cleaned sample fraction(s) are concentrated to a small volume before quantification

Though dioxin-like PCBs have high boiling points, vapour phase transfer mechanisms and aerosol formation during solvent evaporation might lead to substantial losses when concentrating volumes below 10 ml Depending on the method used for solvent volume reduction, the following precautions have to be taken into consideration:

a) Rotary evaporators Losses might be substantial when reducing solvent volumes below 10 ml Counter measures are use of controlled vacuum conditions according to the vapour pressure and boiling point of the solvent, addition of

a high-boiling solvent as a keeper, as well as use of specially shaped vessels (e.g V-shaped)

b) Counter gas flow evaporators Volumes should not be reduced to less than 1 ml

c) Nitrogen flow

An excessive flow of nitrogen which disturbs the solvent surface should be avoided The vial shape has also some influence on possible losses V-shaped vials or vial inserts shall be used for volume reductions below around 200 µl

8.5 Addition of recovery standards

The very last step before injection is the addition of the recovery standards to measure the recovery rates of the extraction standards The recovery standards shall be added under following conditions:

a) Recovery standards in a minimum volume of 10 µl shall be added just prior to the injection If the 12 dioxin-like PCBs are collected and concentrated in several fractions during clean-up procedure, at least one of the three 13C12-labelled congeners mentioned as recovery standards in Table 1 shall be added to each PCB containing fraction Recovery standard and the respective extraction standards shall match together with respect to retention time and mass range

b) Slow evaporation to the final volume is allowed after the addition of the recovery standard The final volume shall not be less than 10 µl The upper limit of the final volume is given by the calibration range c) Samples with the recovery standard added which could not be analysed due to operational reasons (instrument failure), should be stored for as brief a time as possible and any further uncontrolled solvent evaporation shall be avoided

8.6 Principle of identification and quantification

The method specified in this document is based on using gas chromatography/mass spectrometry combined with the isotope dilution technique to enable separation, detection and quantification of dioxin-like PCBs in the extracts of emission samples The internal standard method is applied to determining the recovery rates of the labelled PCBs, used as sampling and extraction standards

The gas chromatographic parameters offer information that enables identification of isomers (position of Cl substituents), whereas the mass spectrometric parameters enable differentiation between congeners with different numbers of chlorine substituents

Table 2 — Concentrations of PCB congeners in calibration solutions

Congeners

Solution concentrations (pg/µl)

standard solution std 1 standard solution std 2 standard solution std 3 standard solution std 4 standard solution std 5 standard solution std 6

In addition, a full five point calibration shall be repeated after major changes such as:

a) use of new or repaired equipment;

b) replacement of GC columns;

c) after ion source cleaning

The relative response factors are used together with the 13C12-labelled congeners, added to the sample to quantify the mass of the native PCBs by the isotope dilution method

The gas chromatographic parameters offer information that enables identification of isomers (position of Cl

substituents), whereas the mass spectrometric parameters enable differentiation between congeners with

different numbers of chlorine substituents

8.7 Calibration of the HRGC/HRMS

Quantification shall be carried out within the linear range of the system This range has to be determined

during the calibration procedure

The calibration curve is used to calculate the analyte relative response factors Calibration itself is carried out

with at least five calibration solutions These solutions contain all native dioxin-like PCBs in defined amounts

and all 13C12-labelled standards (sampling, extraction and recovery standards) The calibration range should

encompass the PCB concentrations of the sample Table 2 shows the concentrations of the calibration

solution for the concentration range of 0,01 ng WHO-TEQPCB/m3 For determining significantly higher

concentrations than 0,01 ng WHO-TEQPCB/m3 solution std 6 should be used instead of solution std 1 Further

recommendations for the measurement of very high concentrations are given in Annex D

Table 2 — Concentrations of PCB congeners in calibration solutions

Congeners

Solution concentrations (pg/µl)

standard solution std 1 standard solution std 2 standard solution std 3 standard solution std 4 standard solution std 5 standard solution std 6

Calibration frequency depends on the stability of the instrument Daily calibration checks shall be run with at

least one of the standard solutions of Table 2 If the deviation of a single injected calibration standard exceeds

20 % a full five point calibration shall be carried out This deviation is calculated as the average of the absolute

values of the deviation of the relative response factors of the 12 PCBs A full five point calibration shall also be

performed, if the deviation for PCB 126 exceeds 20 %

In addition, a full five point calibration shall be repeated after major changes such as:

a) use of new or repaired equipment;

b) replacement of GC columns;

c) after ion source cleaning

The relative response factors are used together with the 13C12-labelled congeners, added to the sample to

quantify the mass of the native PCBs by the isotope dilution method

The relative response factor for congener i is defined and calculated as follows:

rrf i =

C C

i

i A

i i

Q

where

i rrf is the relative response factor of native congener i relative to 13C12-labelled congener i;

C C

i

i A

i i

Q Q

is the inverse mass ratio of 13C12-labelled congener i and native congener i

The calibration curve is a plot of the mass ratio

C C

C C

i

i A

A

13

12 (y-axis) (see Figure 2.)

Figure 2 — HRGC/HRMS calibration curve of the mass ratio

C C

i

i A

A

13 12

8.8 Quantification of HRGC/HRMS results

8.8.1 Quantification of the sample

The mass of congener i in the sample is calculated as follows:

C

C C C

i

i i

i

A rrf

Q

Q

13

12 13

rrf is the relative response factor of native congener i relative to 13C12-labelled congener i

The responses of all detected masses of the PCBs in the samples shall be within the linear range of the method (see Clause 11) Overlap in the mass window between high isotopic (i.e M+12, M+14) of the native PCBs with the lower isotopic ions (M, M+2) of the 13C12-labelled standards, will result in a significant deviation from linearity beyond a mass ratio of 10, especially for higher chlorinated congeners

Every native dioxin-like PCB congener is quantified against its corresponding labelled 13C12-PCB congener Table 3 shows the theoretical isotope ratio for all PCBs with four to seven chlorine substituents examples for monitored PCBs

Table 3 — Mass of ions for PCBs (informative)

8.8.2 Calculation of the recovery rates of the extraction standards

The extraction standards are quantified against the recovery standards as given in Table 1 using Equation (5)

8.8 Quantification of HRGC/HRMS results

8.8.1 Quantification of the sample

The mass of congener i in the sample is calculated as follows:

C

C C

C

i

i i

i

A rrf

Q

Q

13

12 13

rrf is the relative response factor of native congener i relative to 13C12-labelled congener i

The responses of all detected masses of the PCBs in the samples shall be within the linear range of the

method (see Clause 11) Overlap in the mass window between high isotopic (i.e M+12, M+14) of the native

PCBs with the lower isotopic ions (M, M+2) of the 13C12-labelled standards, will result in a significant deviation

from linearity beyond a mass ratio of 10, especially for higher chlorinated congeners

Every native dioxin-like PCB congener is quantified against its corresponding labelled 13C12-PCB congener

Table 3 shows the theoretical isotope ratio for all PCBs with four to seven chlorine substituents examples for

monitored PCBs

Table 3 — Mass of ions for PCBs (informative)

8.8.2 Calculation of the recovery rates of the extraction standards

The extraction standards are quantified against the recovery standards as given in Table 1 using Equation (5)

re

e re e

e 100

i

i i

i i

A rrf

Q Q

If more than one recovery standard is used (see Table 1) the number of chlorine atoms in corresponding standards should be equal or as similar as possible to the extraction standard

8.8.3 Calculation of the recovery rates of the sampling standards

The sampling standards are quantified against the extraction standards shown in Table 4 using Equation (6)

e

sa e sa

sa 100

i

i i

i i

A rrf

Q Q

Table 4 — Calculation scheme for the recovery rates of the sampling standards Sampling standard Extraction standard

13C12-2,3,4,4'-TeCB (60) 13C12-3,3’,4,4’-TeCB (77)

13C12-3,3’,4,5,5’-PeCB (127) 13C12-2,3’,4,4’,5-PeCB (118)

13C12-2,3,3',4,5,5'-HxCB (159) 13C12-2,3,3’,4,4’,5-HxCB (156)Sampling standards and extraction standards shall be in the same fraction If the PCBs are separated into different fractions during the clean-up, it can happen that the calculation scheme of Table 4 is not applicable,

an alternative example is given in Annex B (Table B.1)

8.9 Calculation of the measurement results

PCB emission concentrations are expressed as the mass of PCB per cubic metre of dry waste gas at reference temperature, reference pressure and where appropriate reference oxygen (or carbon dioxide) concentration All these details shall be stated in the report

The WHO-TEQPCB concentration is calculated by the addition of the concentrations of the twelve individual PCBs when multiplied by the appropriate WHO-TEF (see Annex A)

nr

where

CT is the concentration of the emitted dioxin-like PCB expressed as WHO-TEQPCB under

standard conditions dry and reference conditions;

Qi12C is the mass of the emitted PCB-congener i;

Vnr is the waste gas volume of the sample under standard conditions dry and reference

conditions calculated in accordance with Formula (5) of EN 1948–1:2006;

WHO-TEFi is the WHO-TEF of congener i

If the mass of a congener or congeners is below the limit of quantification, then two WHO-TEQPCB

concentrations should be reported per sample:

a) with the mass of those congener(s) below the limit of quantification being taken as equal to the limit of quantification;

b) with the mass of those congener(s) taken as zero

The Total WHO-TEQ concentration of PCDD/PCDF and PCB is calculated accordingly If the filter/condenser method with flow division is used (see EN 1948-1.2006, 5.1.2), and the side stream sample is analysed separately from the filter, it shall be taken into account that the concentrations and not the masses of the congeners are used

8.9 Calculation of the measurement results

PCB emission concentrations are expressed as the mass of PCB per cubic metre of dry waste gas at

reference temperature, reference pressure and where appropriate reference oxygen (or carbon dioxide)

concentration All these details shall be stated in the report

The WHO-TEQPCB concentration is calculated by the addition of the concentrations of the twelve individual

PCBs when multiplied by the appropriate WHO-TEF (see Annex A)

nr

where

CT is the concentration of the emitted dioxin-like PCB expressed as WHO-TEQPCB under

standard conditions dry and reference conditions;

Qi12C is the mass of the emitted PCB-congener i;

Vnr is the waste gas volume of the sample under standard conditions dry and reference

conditions calculated in accordance with Formula (5) of EN 1948–1:2006;

WHO-TEFi is the WHO-TEF of congener i

If the mass of a congener or congeners is below the limit of quantification, then two WHO-TEQPCB

concentrations should be reported per sample:

a) with the mass of those congener(s) below the limit of quantification being taken as equal to the limit of

quantification;

b) with the mass of those congener(s) taken as zero

The Total WHO-TEQ concentration of PCDD/PCDF and PCB is calculated accordingly If the filter/condenser

method with flow division is used (see EN 1948-1.2006, 5.1.2), and the side stream sample is analysed

separately from the filter, it shall be taken into account that the concentrations and not the masses of the

congeners are used

8.10 Analytical report

The analytical report shall include at least the following information and information as to whether these

requirements have been fulfilled, to demonstrate compliance with this document:

1) analysis was performed in accordance with EN 1948-2 and this document;

2) in the case of deviations from this document (e.g exceeding the calibration range), justification(s) shall be given;

c) precision:

1) indication of the reproducibility and repeatability which may be expected under similar conditions to the validation measurements are given in this European Standard (see Clause 9 and Annex C); d) sample storage:

1) location of sample storage between sampling and extraction;

2) temperature of the sample storage location;

3) date at which the samples were put into storage;

e) extraction:

1) sampling train compartments to which the extraction standards were added and in what proportion and at what date;

2) recovery rate of each sampling standard;

3) recovery rate of each extraction standard;

f) concentration:

1) final extract volume after concentration;

g) addition of recovery standards:

1) date of recovery standard addition;

2) date of injection;

3) extract volume at injection;

h) result and additional information:

1) mass of PCB per cubic metre of dry waste gas at reference temperature, reference pressure and where appropriate reference oxygen (or carbon dioxide) concentration;

2) reference conditions as specified (reference temperature, reference pressure, reference oxygen (or carbon dioxide) concentration where appropriate)

9 Method validation

9.1 General

Before carrying out real measurements proper application of the method and suitability of the devices and materials used have to be checked and documented in detail at least once for each design of sampling train Each modification of the sampling train design and/or devices and materials used requires re-validation of the method

9.2 Validation of sampling

Breakthrough of each design of sampling train shall be tested at least once In this validation trial an additional ad/absorption stage shall be used at the end of that part of the sampling train in which the sample is collected Breakthrough of the original sampling train shall be less than 10 % for every single congener The validation of the breakthrough behaviour should be performed at sources with expected emission concentrations at least ten times higher than the quantification limits If the concentrations of the single PCB congeners in the last adsorption stage are lower than the quantification limits, these quantification limits may be used for assessing the breakthrough behaviour

NOTE Trapping efficiency of the adsorption stage can be lower for PCBs (mainly tri- and tetrachloro PCBs) than for PCDDs and PCDFs, and should therefore be demonstrated by these validation trials

Sufficient sample volume shall be collected during these validation trials to ensure a quantification limit less than 5 % of the total amount of sampled PCB on a TEQ basis

9.3 Validation of Analytical Extraction and Clean-up

9.3.1 Extraction

The efficiency of the extraction method used shall be measured before the first use on real samples and documented as part of the method description The measurement of the extraction efficiency shall be repeated in justified cases (e.g for high carbon load of the filter)

a) The extract of a repeated extraction procedure shall not contain more than 5 % of the amount of any individual native congener compared with the first extraction For the second extraction the addition of

13C12-labelled extraction standards is repeated

b) Corrective action shall be taken if the extraction efficiency falls below the acceptable requirement given in a) This validation criterion shall be fulfilled for all parts of the sampling device that can contain a part of the sample such as (where applicable) filters, ab/adsorbents, condensate, vessels and surfaces of the sampling device

or less from the more toxic mono- and non-ortho-substituted dioxin-like PCBs Therefore, isomer pattern and congener profile are not suitable criteria to check the clean-up procedure For the PCB clean-up procedure, it

is important to meet the minimum requirements in 10.4

The validation is performed by using a solution containing only the extraction standards for the PCB clean-up procedure The recovery rate for each individual 13C12-labelled PCB congener shall be at least 80 %

10 Quality control requirements for the measurement

10.1 Use of a validated method

A method of sampling and analysis which has been shown to meet the validation requirements in Clause 9 shall be used

9.2 Validation of sampling

Breakthrough of each design of sampling train shall be tested at least once In this validation trial an additional

ad/absorption stage shall be used at the end of that part of the sampling train in which the sample is collected

Breakthrough of the original sampling train shall be less than 10 % for every single congener The validation of

the breakthrough behaviour should be performed at sources with expected emission concentrations at least

ten times higher than the quantification limits If the concentrations of the single PCB congeners in the last

adsorption stage are lower than the quantification limits, these quantification limits may be used for assessing

the breakthrough behaviour

NOTE Trapping efficiency of the adsorption stage can be lower for PCBs (mainly tri- and tetrachloro PCBs) than for

PCDDs and PCDFs, and should therefore be demonstrated by these validation trials

Sufficient sample volume shall be collected during these validation trials to ensure a quantification limit less

than 5 % of the total amount of sampled PCB on a TEQ basis

9.3 Validation of Analytical Extraction and Clean-up

9.3.1 Extraction

The efficiency of the extraction method used shall be measured before the first use on real samples and

documented as part of the method description The measurement of the extraction efficiency shall be

repeated in justified cases (e.g for high carbon load of the filter)

a) The extract of a repeated extraction procedure shall not contain more than 5 % of the amount of any

individual native congener compared with the first extraction For the second extraction the addition of

13C12-labelled extraction standards is repeated

b) Corrective action shall be taken if the extraction efficiency falls below the acceptable requirement given in

a) This validation criterion shall be fulfilled for all parts of the sampling device that can contain a part of

the sample such as (where applicable) filters, ab/adsorbents, condensate, vessels and surfaces of the

sampling device

9.3.2 Clean-up

Sample clean-up depends on the type of sample matrix that shall be removed Therefore, a single

well-defined clean-up procedure shall not be applied to all sample matrices without a preliminary check

In contrast to PCDD/PCDF analysis, where the isomer pattern and congener profile of a well characterised

sample extract shall not be altered by the applied clean-up procedure (EN 1948-2:2006, 7.3.1, a)), it is

intended within the analysis of dioxin-like PCB, to separate the less toxic di-ortho-substituted congeners more

or less from the more toxic mono- and non-ortho-substituted dioxin-like PCBs Therefore, isomer pattern and

congener profile are not suitable criteria to check the clean-up procedure For the PCB clean-up procedure, it

is important to meet the minimum requirements in 10.4

The validation is performed by using a solution containing only the extraction standards for the PCB clean-up

procedure The recovery rate for each individual 13C12-labelled PCB congener shall be at least 80 %

10 Quality control requirements for the measurement

10.1 Use of a validated method

A method of sampling and analysis which has been shown to meet the validation requirements in Clause 9

shall be used

10.2 Use of 13C12-labelled standards

13C12-labelled PCBs are added before sampling (sampling standards), before extraction (extraction standards) and just before the GC injection (recovery standards) The recovery standards are assumed to be transferred

to the analytical system without any loss and allowed to determine the recoveries (or losses) of the congeners added at earlier stages

Sampling standards are added to the sampling device before starting sampling 13C12-labelled congeners introduced at this stage might not be exposed to completely the same mechanisms of losses as the native PCBs collected during the sampling period First, the labelled congeners are exposed to the gas flow during the entire sampling time while the native PCBs are present, on average, only half the time Second, a significant fraction of the sampled native PCBs are bound to particles and, therefore, they can have different susceptibilities to reactions and mechanisms which might lead to losses 13C12-labelled congeners added prior

to sampling might be subject to loss mechanisms before the sample begins to be taken Their use as internal standards for quantification can lead to an overestimation of the measured concentrations Therefore, the only purpose of the isotope labelled standards added before sampling (see Table 1) is to identify anomalies during sampling They are not used for quantification

10.3 Minimum requirements for sampling

Particle bound and filter passing PCBs shall be sampled according to EN 1948-1

a) The sampling shall be performed according to the requirements for isokinetic sampling specified in

EN 13284-1

b) Filter efficiency shall be better than 99,5 % on a test aerosol with a mean particle diameter of 0,3 µm, at the maximum flow rate anticipated (or 99,9 % on a test aerosol of 0,6 µm mean diameter) This efficiency shall be certified by the filter supplier (EN 13284-1:2001, 6.2.7)

c) The filter is placed upstream of the adsorption stage in case of the filter-condenser method and the dilution method, or before the last adsorption stage in case of the cooled probe method

d) According to the sampling prescriptions for the filter/condenser method, the filter should be kept beneath

125 °C, but above the flue gas dew point

e) Adsorption stage for collecting the filter passing PCBs shall be part of the sampling train This can be a solid adsorbent or impingers

f) Recovery rate of each of the 13C12-labelled sampling standards shall be greater than 50 %, calculated on the basis of the relevant extraction standard

g) The further minimum requirements for sampling and for determining the field blank given in

EN 1948-1:2006, 7.2 and 7.3 shall be complied with

h) PCB concentration of the field blank assuming the same volume as for sampling shall not exceed 10 % of the relevant limit value (expressed in TEQ) or the measured concentration if above the limit value The total TEQ value (PCDD/PCDFs and PCBs) of the field blank shall also not exceed 10 % of the relevant limit value If the determined measurement value is less than the preceding field blank value, the reported result is defined as less than or equal to the blank

NOTE In case of monitoring PCDD/PCDF and dioxin-like PCB emissions significantly lower than 0,1 ng Total TEQ/m3, the field blank can be in the same range as the measured concentration, which will have a higher relative uncertainty

WHO-As long as a limit value for PCBs or for PCDD/PCDFs together with PCBs in emissions does not exist, the limit value for PCDD/PCDFs (actually 0,1 ng I-TEQ/m3) has to be considered for field blank determination

10.4 Minimum requirements for extraction and clean-up

a) Any particles collected during sampling on the particle collecting media (glass fibre filters, thimbles, glass wool, etc.) using any of the three methods shall be treated with hydrochloric acid [13]

b) All collected particles and all adsorbents shall be extracted with toluene for 20 h in a Soxhlet extractor or comparable validated method

c) To achieve sufficient quantification limits, the cleaned sample fraction(s) shall be concentrated to a small volume before quantification, but not less than 10 µl (by using small volumes solubility problems can arise for some congeners, in these cases a higher volume is recommended)

d) Recovery rate for each of the individual congeners of the 13C12-labelled dioxin-like PCB congeners added before extraction shall be at least 40 % and shall not exceed 120 % In exceptional cases, a recovery rate

of 20 % to 150 % can be accepted for the field sample, if the contribution of an individual congener to the WHO-TEQPCB is less than 10 %

10.5 Minimum requirements for identification of PCB congeners

a) High resolution gas chromatography/high resolution mass spectrometry at a resolution of greater or equal

to 10 000 is at present required to achieve adequate sensitivity, selectivity and to allow the use of all the

13C12-labelled standards

b) Identification shall be based at least on two ions of the molecular isotope cluster

c) Isotope ratio between the ions monitored shall match the theoretical value within ± 15 % (see Table 3) d) Retention time of a native dioxin-like PCB congener shall be within a time window of + 3 s to 0 s based on the retention time of the corresponding 13C12-labelled congener in the sample

e) Signal-to-noise ratio S/N of the raw data, as documented in Figure 3, shall be at least 3:1 for the native

signal used for identification

f) Ideally, base line noise shall be measured in front of the signal of the native congener within a signal-free window corresponding to ten times the signal width at half height Peak-to-peak values are taken

10.4 Minimum requirements for extraction and clean-up

a) Any particles collected during sampling on the particle collecting media (glass fibre filters, thimbles, glass

wool, etc.) using any of the three methods shall be treated with hydrochloric acid [13]

b) All collected particles and all adsorbents shall be extracted with toluene for 20 h in a Soxhlet extractor or

comparable validated method

c) To achieve sufficient quantification limits, the cleaned sample fraction(s) shall be concentrated to a small

volume before quantification, but not less than 10 µl (by using small volumes solubility problems can arise

for some congeners, in these cases a higher volume is recommended)

d) Recovery rate for each of the individual congeners of the 13C12-labelled dioxin-like PCB congeners added

before extraction shall be at least 40 % and shall not exceed 120 % In exceptional cases, a recovery rate

of 20 % to 150 % can be accepted for the field sample, if the contribution of an individual congener to the

WHO-TEQPCB is less than 10 %

10.5 Minimum requirements for identification of PCB congeners

a) High resolution gas chromatography/high resolution mass spectrometry at a resolution of greater or equal

to 10 000 is at present required to achieve adequate sensitivity, selectivity and to allow the use of all the

13C12-labelled standards

b) Identification shall be based at least on two ions of the molecular isotope cluster

c) Isotope ratio between the ions monitored shall match the theoretical value within ± 15 % (see Table 3)

d) Retention time of a native dioxin-like PCB congener shall be within a time window of + 3 s to 0 s based on

the retention time of the corresponding 13C12-labelled congener in the sample

e) Signal-to-noise ratio S/N of the raw data, as documented in Figure 3, shall be at least 3:1 for the native

signal used for identification

f) Ideally, base line noise shall be measured in front of the signal of the native congener within a signal-free

window corresponding to ten times the signal width at half height Peak-to-peak values are taken

Key

S signal height

N peak-to-peak-noise

W 10 × signal width at half height

Figure 3 — Determination of the signal-to-noise ratio

10.6 Minimum requirements for quantification

In addition to the requirements for identification, the following points shall be fulfilled as quantification requirements:

a) Separation of all investigated dioxin-like PCB congeners relevant for the WHO-TEQPCB shall be demonstrated by using standard reference mixtures

b) Peak shape of the gas chromatographic signal of a congener shall contain ten or more sampling points (scanning units)

c) PCB 126 shall be separated from all other interfering congeners by at least a 25 % valley

d) For quantification the signal-to-noise ratio of the native congeners shall be 10:1 The signal-to-noise ratio

of the 13C12-labelled congeners used for quantification shall be > 20:1

e) Measuring range used shall be linear (at least over a concentration range of a factor of 100) The standard deviation of the relative response factor shall not exceed ± 15 % and shall be based on a minimum of five measuring points which cover the whole range

f) Permissible limits of quantification (LOQs) for the single congener i shall be as follows:

i i

LOQ

TEF - WHO

pg/m 5 ,

WHO-TEF i is the World Health Organisation toxic equivalency factor for congener i

g) Quantification is based on two isotope ions If quantification is possible only with one single ion due to disturbed second trace or, in case of PeCB second and third trace, this has to be reported

h) A chromatography column shall be chosen so that the fragmentation products of chlorine loss(es) of higher chlorinated PCBs shall not overlap with other PCBs of interest with one or two chlorine atoms less i) Interference with other compounds especially PCDDs shall be avoided by a suitable chromatographic column and/or temperature programme or an optimised clean-up

11 Quality assurance criteria for extraction/clean-up/quantification procedure blanks

11.1 Analytical blank

Regular determination of blanks covering the whole analytical procedure is an important part of quality assurance within analysis of dioxin-like PCBs The analytical blank value of all dioxin-like PCB congeners shall be measured in a blank sample covering the complete analytical procedure including extraction, clean-

up, and quantification when one of the following situations occurs:

a) after a series of no more than ten samples;

b) after major changes in the extraction or clean-up procedure such as:

1) use of new or repaired equipment;

2) use of new batches of solvents or adsorbents;

c) after the analysis of a sample with unusually high levels exceeding average concentration levels by a factor 10

An analytical blank can be accepted when the following two requirements are fulfilled:

d) analytical blank value of all dioxin-like PCB congeners shall be lower than the lowest measured value in the samples;

e) for the two PCB congeners with the highest TEFs (PCB 126 and PCB 169), the analytical blank shall be

at least by the factor of 10, lower than the set quantification limit of the method For the other 10 PCB congeners the analytical blank shall be at least by the factor of 5, lower than the quantification limit

If the analytical blank values exceed the values mentioned above, the laboratory specific quantification limit has to be adopted (increased) correspondingly

11.2 HRGC/HRMS blank

A HRGC/HRMS blank shall be measured on a regular basis in addition to the analytical blank This HRGC/HRMS blank shall ensure that there will be no contamination from the measuring system itself or the sample ahead (e.g syringe, previous sample, standard solution, septum, etc.)

For this purpose toluene has to be injected, the toluene chromatogram has to be checked for all dioxin-like PCBs and for all 13C-standards The relevant signals shall be below the detection limit but at least lower than

5 % related to the corresponding signals of the next sample

For HRGC/HRMS blank measurements the injection volume shall be the same as for the samples

WHO-TEF i is the World Health Organisation toxic equivalency factor for congener i

g) Quantification is based on two isotope ions If quantification is possible only with one single ion due to

disturbed second trace or, in case of PeCB second and third trace, this has to be reported

h) A chromatography column shall be chosen so that the fragmentation products of chlorine loss(es) of

higher chlorinated PCBs shall not overlap with other PCBs of interest with one or two chlorine atoms less

i) Interference with other compounds especially PCDDs shall be avoided by a suitable chromatographic

column and/or temperature programme or an optimised clean-up

11 Quality assurance criteria for extraction/clean-up/quantification procedure blanks

11.1 Analytical blank

Regular determination of blanks covering the whole analytical procedure is an important part of quality

assurance within analysis of dioxin-like PCBs The analytical blank value of all dioxin-like PCB congeners

shall be measured in a blank sample covering the complete analytical procedure including extraction,

clean-up, and quantification when one of the following situations occurs:

a) after a series of no more than ten samples;

b) after major changes in the extraction or clean-up procedure such as:

1) use of new or repaired equipment;

2) use of new batches of solvents or adsorbents;

c) after the analysis of a sample with unusually high levels exceeding average concentration levels by a

factor 10

An analytical blank can be accepted when the following two requirements are fulfilled:

d) analytical blank value of all dioxin-like PCB congeners shall be lower than the lowest measured value in

the samples;

e) for the two PCB congeners with the highest TEFs (PCB 126 and PCB 169), the analytical blank shall be

at least by the factor of 10, lower than the set quantification limit of the method For the other 10 PCB

congeners the analytical blank shall be at least by the factor of 5, lower than the quantification limit

If the analytical blank values exceed the values mentioned above, the laboratory specific quantification limit

has to be adopted (increased) correspondingly

11.2 HRGC/HRMS blank

A HRGC/HRMS blank shall be measured on a regular basis in addition to the analytical blank This

HRGC/HRMS blank shall ensure that there will be no contamination from the measuring system itself or the

sample ahead (e.g syringe, previous sample, standard solution, septum, etc.)

For this purpose toluene has to be injected, the toluene chromatogram has to be checked for all dioxin-like

PCBs and for all 13C-standards The relevant signals shall be below the detection limit but at least lower than

5 % related to the corresponding signals of the next sample

For HRGC/HRMS blank measurements the injection volume shall be the same as for the samples

HRGC/HRMS blank shall be run at least after each ten samples If significantly different concentrations are expected or different sample sources have to be analysed, a HRGC/HRMS blank shall be analysed in between

12 Performance characteristics

12.1 General

This European Standard can be used as a reference method It has been tested in extensive validation trials which allow the establishment of the between laboratory variance and within laboratory variance of this method Because no relevant reference materials for PCBs in exhaust gases are available at this time, no determination of accuracy can be provided

The validation of the method has taken place from 2006 to 2008 financed by the European Commission and EFTA and was performed in three parts [14] resulting in the performance characteristics given in this clause The first part of the validation consisted of an interlaboratory comparison study in December 2006 to February

2007 Here the analytical section of the method was validated by analysing two ash samples, two standards solutions, one ash extract and two sets of complete calibration standards by eight laboratories The results of this study are summarized in 12.2

The second part of the validation of the combined sampling and chemical analysis at a municipal waste incinerator was performed by three sampling teams in combination with three analytical laboratories selected from the interlaboratory comparison study to cover all three sampling techniques; the cooled probe method, the filter/condenser method and the dilution method [15] The comparability of the three methods for PCBs was assumed based on the results of the first validation campaign on PCDD/PCDF The sampling campaign included six sampling days and samples were taken in duplicate using all three methods in the same duct, in addition three field blanks and three breakthrough samples were taken Sampling took place at a state of the art incinerator consisting of three lines of a grate incinerator equipped with a fabric filter with the addition of carbon, a two stage wet scrubber and a selective catalytic reduction unit At this incinerator PCDD/PCDF emissions are normally less than 10 % of the regulation limit of 0,1 ng I-TEQ/m3

The third part of the validation was performed at a shredder plant and included five duplicate emissions measurements and two field blanks [16] In addition PCB breakthrough was validated at two occasions by adding an extra adsorption unit to the sampling equipment and these adsorption units were analyzed separately from the emission samples This additional validation was performed only for the filter/condenser method in order to validate the method at higher concentrations with emphasis on breakthrough and within method variation

12.2 Results of the validation campaign

The total reproducibility covering all three methods (SR) for the WHO PCBs was 0,25 pg TEQ/m3 based on measurements at a municipal waste incinerator over an extreme low concentration range from 0,19 pg TEQ/m3 to 0,41 pg TEQ/m3 The corresponding total reproducibility was 6,8 ng/m3 for the sum of the six marker PCBs over a concentration range from 4,4 ng/m3 to 11 ng/m3

The between laboratory variances for the chemical analysis for the standard solutions and the extract were all below 11 %, the corresponding within laboratory variance was below 5 % For the fly ash samples the between laboratory variance for the WHO PCBs was 12 % and 16 % for the low and high level sample respectively, the corresponding within laboratory variance was 4 % and 8 % The variance for the sum of the marker PCBs were significantly higher both between and within the laboratories varied from 17 % to 47 % This result is surprising because the analysis of WHO TEF assigned PCBs is generally assumed to be more difficult

These concentrations were very close to the LOD values based on the field blanks for the three methods which ranged from 0,11 pg TEQ/m3 to 0,57 pg TEQ/m3 for the WHO PCBs and 1,3 ng/m3 to 14 ng/m3 for the marker PCBs Corresponding LOQ values based on the field blanks varied from 0,20 pg/m3 to 1,37 pg/m3 for the WHO PCBs and from 1,7 ng/m3 to 33 ng/m3 for the marker PCBs,

The levels in the field blank samples were at least two orders of magnitude below the EU limit value for PCDD/PCDF, used in the absence of a limit value for PCBs (see 10.3)

Recoveries of the isotope labelled standards were in good agreement with the requirements given in 10.4, d) The absolute amount of breakthrough at levels just above the detection limit and field blank levels were at least two orders of magnitude below the EU limit for all three methods At the high concentrations of a shredder plant (0,29 ng WHO-TEQPCB/m3 to 0,94 ng WHO-TEQPCB/m3 respectively 3 500 ng/m3 to

26 100 ng/m3 for the marker PCBs) the breakthrough was below 0,6 % for the WHO-TEQPCB and below 6 % for the sum of the marker PCBs for the filter/condenser method

A compilation of the validation results is given in Table 5, all further details and tables are given in Annex C

Table 5 — Compilation of the validation measurement results

a) Interferences by ions of similar mass that cannot be eliminated by the resolution of the mass spectrometer These are above all the PCDDs if they could not have been removed from the dioxin-like PCBs during the clean-up

b) Interferences by fragmentation products of chlorine loss(es) of higher chlorinated PCBs These interferences are difficult to eliminate because the initiating compounds are part of the compounds to be analysed and therefore belong to the sample If the signal coming from those higher chlorinated PCBs cannot be reliably separated from the signals of interest, the quantification limits have to be adapted

These concentrations were very close to the LOD values based on the field blanks for the three methods

which ranged from 0,11 pg TEQ/m3 to 0,57 pg TEQ/m3 for the WHO PCBs and 1,3 ng/m3 to 14 ng/m3 for the

marker PCBs Corresponding LOQ values based on the field blanks varied from 0,20 pg/m3 to 1,37 pg/m3 for

the WHO PCBs and from 1,7 ng/m3 to 33 ng/m3 for the marker PCBs,

The levels in the field blank samples were at least two orders of magnitude below the EU limit value for

PCDD/PCDF, used in the absence of a limit value for PCBs (see 10.3)

Recoveries of the isotope labelled standards were in good agreement with the requirements given in 10.4, d)

The absolute amount of breakthrough at levels just above the detection limit and field blank levels were at

least two orders of magnitude below the EU limit for all three methods At the high concentrations of a

shredder plant (0,29 ng WHO-TEQPCB/m3 to 0,94 ng WHO-TEQPCB/m3 respectively 3 500 ng/m3 to

26 100 ng/m3 for the marker PCBs) the breakthrough was below 0,6 % for the WHO-TEQPCB and below 6 %

for the sum of the marker PCBs for the filter/condenser method

A compilation of the validation results is given in Table 5, all further details and tables are given in Annex C

Table 5 — Compilation of the validation measurement results

Interferences are most likely to occur from compounds that have similar chemical and physical properties

Although clean-up methods are designed to remove very effectively the most common chemicals from the

extract, some interferences remain These can be divided into the following four types:

a) Interferences by ions of similar mass that cannot be eliminated by the resolution of the mass

spectrometer These are above all the PCDDs if they could not have been removed from the dioxin-like

PCBs during the clean-up

b) Interferences by fragmentation products of chlorine loss(es) of higher chlorinated PCBs These

interferences are difficult to eliminate because the initiating compounds are part of the compounds to be

analysed and therefore belong to the sample If the signal coming from those higher chlorinated PCBs

cannot be reliably separated from the signals of interest, the quantification limits have to be adapted

NOTE Special care should be taken with respect to interferences of PCB 126 (see Annex E, Figure E.3) This interference can be avoided by separation of non-ortho PCBs from the other PCBs as described in Annex B

c) Interferences by ions that overlap with the lock mass and therefore shift the mass calibration By choice of another lock mass this interference can be avoided

d) Interferences by big amounts of sample matrix that lower the ion yield during ionisation which causes a significant decrease of sensitivity This effect is particularly strong with electronegative compounds such

as phthalates Interferences like this can be removed by additional and/or repeated clean-up steps Some examples for interferences mentioned above are given in Annex E

Annex A

(informative)

Toxicity and toxic equivalency

The PCBs listed in the WHO proposal of 1997 are considered to show comparable toxicity as substituted PCDDs/PCDFs Some general information on the toxicity effect mechanism and the toxicity equivalency system (TEQ-system) is given in EN 1948-1:2006, Annex A

2,3,7,8-chlorine-The most recent TEQ scheme, developed by the World Health Organisation (WHO) and the International Programme on Chemical Safety (IPCS) standardises the toxicity of 17 PCDD and PCDF congeners and includes for the first time, 12 dioxin-like PCBs It reflects the present knowledge about toxic effects of PCDD/PCDFs and dioxin-like PCBs

The WHO-TEQ approach is linked to a WHO recommendation concerning a Tolerable Daily Intake (TDI) for humans of 1 pg to 4 pg Total WHO-TEQ/kg body weight which should not be exceeded The TDI was recommended on the basis of health effects (including developmental, reproductive, hormonal, immune system and neuro-behavioural effects), dose-response relationships and quantitative risk extrapolation

Table A.1 — WHO Toxic Equivalency Factors (WHO-TEFs) for mammals [9; 10] and

International Toxic Equivalency Factors (I-TEFs) [11] a Congener I-TEF 1988 [11] WHO-TEF 1998 [9] WHO-TEF 2006

Annex A

(informative)

Toxicity and toxic equivalency

The PCBs listed in the WHO proposal of 1997 are considered to show comparable toxicity as

2,3,7,8-chlorine-substituted PCDDs/PCDFs Some general information on the toxicity effect mechanism and the toxicity

equivalency system (TEQ-system) is given in EN 1948-1:2006, Annex A

The most recent TEQ scheme, developed by the World Health Organisation (WHO) and the International

Programme on Chemical Safety (IPCS) standardises the toxicity of 17 PCDD and PCDF congeners and

includes for the first time, 12 dioxin-like PCBs It reflects the present knowledge about toxic effects of

PCDD/PCDFs and dioxin-like PCBs

The WHO-TEQ approach is linked to a WHO recommendation concerning a Tolerable Daily Intake (TDI) for

humans of 1 pg to 4 pg Total WHO-TEQ/kg body weight which should not be exceeded The TDI was

recommended on the basis of health effects (including developmental, reproductive, hormonal, immune

system and neuro-behavioural effects), dose-response relationships and quantitative risk extrapolation

Table A.1 — WHO Toxic Equivalency Factors (WHO-TEFs) for mammals [9; 10] and

International Toxic Equivalency Factors (I-TEFs) [11] a Congener I-TEF 1988 [11] WHO-TEF 1998 [9] WHO-TEF 2006

Annex B

(informative)

Examples of extraction and clean-up procedures

B.1 Example for clean-up of PCB and the separation from PCDD/PCDFs

B.1.1 General

This annex describes a clean up method for separate analysis of PCDD/PCDF and PCB The separation of PCB from PCDD/PCDF is carried out at an aluminium oxide column by different organic solvents and further separation of the PCB into a “non-ortho-fraction” (PCB 77, 81, 126, 169) and a fraction of PCB without “non-ortho PCB” The clean-up follows Figure B.1