WRc Ref: UC8720.05

February 2012

Analysis of Poly-Brominated Biphenyl Ethers

(PBDEs) in Selected UK Waste Streams:

PBDEs in waste electrical and electronic equipment

(WEEE) and end of life vehicles (ELV)

RESTRICTION: This report has the following limited distribution:

External: Defra

© WRc plc 2012 The contents of this document are subject to copyright and all rights are reserved. No part of this document may be reproduced, stored in a retrieval system or transmitted, in any form or by any means electronic, mechanical, photocopying, recording or otherwise, without the prior written consent of WRc plc.

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WRc plc,

Frankland Road, Blagrove,

Swindon, Wiltshire, SN5 8YF

Telephone: + 44 (0) 1793 865000

Fax: + 44 (0) 1793 865001

Website: www.wrcplc.co.uk

Analysis of Poly-Brominated Biphenyl Ethers

(PBDEs) in Selected UK Waste Streams:

PBDEs in waste electrical and electronic equipment (WEEE)

and end of life vehicles (ELV)

Report No.: UC8720.05

Date: February 2012

Authors: James Peacock, Jane Turrell, Kathy Lewin and Edward Glennie

Project Manager: Jane Turrell

Project No.: 15613-0

Client: Defra

Contents

Glossary ................................................................................................................................... 1

Executive Summary ................................................................................................................. 2

1. Introduction .................................................................................................................. 8

1.1 Overview ..................................................................................................................... 8

1.2 Objectives .................................................................................................................... 9

1.3 Background ................................................................................................................. 9

1.4 Total UK WEEE and links to brominated plastics ..................................................... 10

2. Sampling and Testing ............................................................................................... 12

2.1 Sampling ................................................................................................................... 12

2.2 Testing ....................................................................................................................... 15

3. Results ...................................................................................................................... 18

3.1 Introduction ................................................................................................................ 18

3.2 XRFS screening ........................................................................................................ 18

3.3 GCMS analysis .......................................................................................................... 21

4. Discussion ................................................................................................................. 26

4.1 PBDEs in UK WEEE ................................................................................................. 26

4.2 Estimates of PBDEs in UK Waste stream ................................................................. 31

5. Conclusions and Proposals ....................................................................................... 35

5.1 Overview of PBDE congeners in UK WEEE ............................................................. 35

5.2 Levels of listed PBDEs in waste electrical and electronic equipment ....................... 36

5.3 Levels of PBDEs in ELV ............................................................................................ 36

5.4 PBDE Quantification by High Resolution GCMS ...................................................... 36

5.5 Suitability of XRFS as a screening tool ..................................................................... 37

5.6 Proposals for further work ......................................................................................... 37

References ............................................................................................................................. 39

Appendices

Appendix A PBDE Method Development ................................................................... 40

Appendix B Results ..................................................................................................... 43

List of Tables

Table 1.1 UK Waste electrical & electronic equipment (WEEE) collected in 2010

1 .................................................................................... 10

Table 1.2 UK Waste electrical & electronic equipment (WEEE) collected 2010

1 ........................................................................................ 11

Table 2.1 Details of samples collected for PBDE testing ........................................ 13

Table 3.1 PBDE congeners analysed in GCMS analysis ........................................ 19

Table 4.1 Unweighted range data (GCMS) for PBDEs Waste electrical and electronic equipment (WEEE) .......................................................... 26

Table 4.2 Weighted range data (GCMS) for PBDEs Waste electrical and electronic equipment (WEEE) .......................................................... 28

Table 4.3 Weighted average concentrations of the sum of Stockholm listed PBDEs and total PBDEs by WEEE stream ................................... 29

Table 4.4 Summary PBDE data for WEEE ............................................................. 30

Table 4.5 Estimated weights of Stockholm listed PBDEs in key UK WEEE streams ........................................................................................ 34

Table B.1 Samples submitted for GCMS analysis and XRFS screening data .......................................................................................................... 43

Table B.2 MSS GCMS PBDE test data ................................................................... 44

Table B.3 Detailed breakdown of MSS GCMS analysis data .................................. 46

Table B.4 Correlation in GCMS data between hepta- and deca-BDE ..................... 48

Table B.5 Estimated confidence limits for range estimates of PBDEs in UK waste stream ..................................................................................... 50

Table B.6 Samples tested for interlaboratory comparison ....................................... 51

Table B.7 Summary of MSS and Fraunhofer PBDE results .................................... 52

Table B.8 Comparison of MSS and Fraunhofer PBDE results ................................ 53

Table B.9 Summary of interlaboratory GCMS data comparison ............................. 54

List of Figures

Figure 2.1 Sampling approach for PBDEs in WEEE and ELV ................................. 14

Figure 3.1 Concentration of bromine in selected electrical components by portable XRFS unit ............................................................................. 20

Figure 3.2 Plot showing range of concentrations of Br in samples of computer casings by XRFS ..................................................................... 21

Figure 3.3 PBDE concentrations in various whole electrical components taken from UK waste sites ....................................................................... 22

Figure 3.4 Plot showing PBDE concentrations in a bulk sample of shredded computer casings .................................................................... 24

Figure 3.5 Plot showing PBDE concentrations in bulk sample (A17) of shredded computer casings excluding nona- and deca-BDE ................. 25

Figure 3.6 Plot showing PBDE concentrations in sample (A28) - television casings .................................................................................... 25

Figure 4.1 Plot showing PBDE concentrations in shredded bulk WEEE samples ................................................................................................... 27

Figure B.1 Histogram of hepta-BDE concentrations in all WEEE categories, excluding TVs ....................................................................... 47

Figure B.2 Histogram of hepta-BDE concentrations in sampled TVs ....................... 47

Figure B.3 Scatter graph hepta and deca PBDE concentrations (all ‘whole’ samples & sub-samples) ............................................................. 48

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Glossary

Aqua regia Mixture of hydrochloric and nitric acid, used hot to digest solid samples for determination of mineral acid soluble ‘total’ concentration

ASR Automotive shredder residue

BS EN 14899 British/European Standard Framework for the Development of a Sampling Plan

CEN/TC292 European Committee for Standardization Technical Committee 292 – on the characterisation of waste

ELV End of life vehicles

EU European Union

GCMS Gas chromatography – mass spectrometry – an analysis technique used for determination of PBDEs

HIP High impact polystyrene

ICER Industry Council for Electronic Equipment

LOD Limit of detection

MSS Marchwood Scientific Services

PBDEs Polybrominated diphenyl ethers – a group of compounds used as a flame retardant in plastics used in electronics

Printed circuit board Printed circuit board

PeCB Pentachlorobenzene

POPs Persistent organic pollutants

PUR or PU Polyurethane

RoHS Restriction of hazardous substances

TBBPA Tetrabromobisphenol A

UNEP United Nations Environment Programme

WEEE Waste electrical and electronic equipment

XRFS X-ray fluorescence spectrometry

(xxx)-BDE Brominated diphenylether – where (xxx) denotes the level of bromination (hepta-, octa-, nona- deca- etc.)

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Executive Summary

i Background

Polybrominated diphenyl ethers (PBDEs) have been in use as flame retardants in plastic and foam

items within electrical and electronic equipment and motor vehicles since the 1970s, and as such will

be present in the waste stream of these products when they are discarded. There are a total of 209

PBDE congeners, which are categorised into 10 groups on the basis of their level of bromination, using

a pre-fix i.e. tri-, tetra-, penta-, hexa-, hepta-, octa, nono- and deca-BDE.

As part of implementation of the Persistent Organic Pollutants Regulation (Regulation 850/2004/EC)

the EU intend to set limit values for new substances added to the annexes of the Stockholm

Convention on Persistent Organic Pollutants (2009) for specific waste streams which include waste

electrical and electronic equipment and end of life vehicles. The impact of such limit setting on UK

business is unclear as the data on PBDEs levels in these waste streams is sparse.

Newly listed substances under the Stockholm Convention include the fire retardants tetra- penta-, hexa-

and hepta-BDEs. Although their use in manufacture has been restricted within the EU since 2003-4,

they may still be present in items within waste electrical and electronic equipment and end of life

vehicles that are manufactured outside of the EU or that incorporate plastic recyclate that contains

listed PBDEs.

This report details the information collected through a Defra funded project to generate new data on the

ranges of PBDEs found in United Kingdom (UK) waste electrical and electronic equipment and end of

life vehicles to support Defra in the implementation of the Persistent Organic Pollutant Regulation. This

study provides initial quantification of the concentration ranges of PBDEs that might be expected in the

plastics and foam components of waste electrical and electronic equipment. Further testing is required

to confirm the extent of the concentration ranges found in waste electrical and electronic equipment

component stream. Samples of end of life vehicles will be collected in January 2012.

ii Approach

A laboratory based high resolution gas chromatography with mass spectrometry method was

developed by a UK laboratory to enable testing of PBDEs in plastic matrices. Target congeners, which

are the primary constituents of commercial flame retardant formulations were used as markers for each

of the bromination groups. WRc collected samples of waste electrical and electronic items from a

number of UK sites and processes where Waste Electrical and Electronic Equipment is treated to

assess the degree of contamination in the overall waste stream and attempt estimates for PBDE

concentrations in UK waste electrical and electronic equipment. The use of a portable X-Ray

fluorescence spectrometer to provide a crude screen for the presence of total bromine, as a potential

indicator of PBDE contaminated plastics was also investigated. A protocol was developed based on a

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30 second scan time. This provides a limit of detection for total bromine of circa 5-10 mg/kg, and

equates to a detection limit in a brominated compound containing 50% bromine (i.e. penta PBDE) of

approximately 10 to 20 mg/kg. The detection limit would be slightly better for a compound with a higher

level of bromination.

The aim of the sampling programme was to collect samples for testing by sensitive analytical

techniques and assess the usefulness of X-Ray fluorescence spectrometry as a screening tool for

PBDEs that could be used in the field.

The sampling programme aimed to encompass a good cross-section of waste electrical and electronic

equipment fractions to provide an indication of common contaminant concentration ranges. The

samples collected represent circa 97.5% of total UK waste electrical and electronic equipment waste

arisings. Sample collection and testing focussed on shredded ‘single component’ waste electrical and

electronic equipment rather than whole single items. This approach ensured that the majority of

samples, although spot samples in time, were representative of a large number of individual units and

therefore the wider UK waste stream.

iii Conclusions

Overview of PBDE congeners in UK waste electrical and electronic equipment:

Consistently low (in terms of fire retardant concentrations) but detectable levels of the newly listed

PBDEs of interest were seen in all items tested. Since it is believed that these samples are

representative of wider UK waste electrical and electronic equipment, this equates to widespread listed

PBDE contamination across this stream. The presence of listed PBDEs is usually, but not always,

associated with higher and more variable concentrations of nona-and deca-BDEs. Nona-206 and deca-

209 BDEs are the dominant PBDEs found in both single component waste electrical and electronic

equipment and shredded waste electrical and electronic equipment consisting of multiple components.

Both nona and deca PBDEs are still routinely used as flame retardants in manufacturing, but neither

are Stockholm Convention listed persistent organic pollutants.

Levels of listed PBDEs in waste electrical and electronic equipment: Typical weighted

average concentrations of the sum of listed PBDEs (i.e. tetra-, penta-, hexa-,and hepta- BDE) versus

total PBDE concentrations (i.e. including nona- and deca- BDE) are provided in Table 1. The table is

colour coded, showing highest concentrations in red, through orange to green which represent the

lowest concentrations. The significant concentrations of listed PBDEs in printed circuit boards, TVs and

industrial IT equipment are such that they may exceed future EU limits. This is of major significance if

we consider that the contribution of IT equipment and TVs is circa 34% of the total UK waste electrical

and electronic equipment stream and potentially poses a significant problem to waste electrical and

electronic equipment recycling in the UK. Management measures may be needed to remove

contaminated material prior to re-processing. The PBDE concentrations detected in all the waste

electrical and electronic equipment streams tested in this study would fail to meet some proposed lower

limits for some PBDE bromination groups. Of the listed PBDEs, hepta-BDE and to a lesser extent hexa-

BDE appear to be the predominant listed contaminants, particularly in TVs, IT equipment (PC monitors)

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and digiboxes. Each sample of shredded waste electrical and electronic equipment tested by GCMS is

representative of at least 100 units, although the number of samples tested in relatively small, 42 in

total (and smaller within each waste stream) the data is believed to provide a representative snap-shot

of each waste stream.

The concentrations of listed PBDEs vary from < 1 - 36,500 mg/kg but are generally below 5000 mg/kg.

This concentration is too low to be effective as a flame retardant and it is believed that these plastic

items have been contaminated through incorporation of plastic recyclate containing listed PBDEs into

new manufactured products.

Table 1 Average concentrations of Stockholm listed PBDEs versus total PBDEs in UK

waste electrical and electronic equipment as determined in this study

Category Average total tetra, penta,

hexa, hepta- PBDE (mg/kg)

Average total PBDE

(mg/kg)

TVs 5746 90777

Industrial IT equipment 4610 29073

Printed circuit boards 4473 26493

Digiboxes 858 5825

Large household appliances 512 1951

Small household appliances 57 847

Fridges 39 182

PC monitors 14 12353

Sum of Stockholm listed PBDEs Sum of total PBDEs

This suggests that although dilution of listed PBDEs will occur during repeated recycling, it will take a

considerable time to eradicate these substances from the waste electrical and electronic equipment

stream unless measures are put in place to remove them prior to re-processing or the process has a

suitable separation stage. From the initial findings of this study it could be a number of decades before

the UK might expect to see PBDE free consumer goods being discarded.

Estimates have been made of the proportion of waste contaminated by Stockholm Convention listed

PBDEs for the UK waste stream in Table 2, but these should be viewed with caution for a number of

reasons:

Firstly, data on waste arisings are only available at an amalgamated level for generic categories

e.g. the category ‘display equipment’ contains both TV and PC monitors that have been found to

have differing PBDE characteristics. The proportion of the total weight of the PBDE containing

components requires further verification and in some cases this data is not currently available.

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Table 2 Estimated weights of Stockholm listed PBDEs in key UK WEEE streams

Waste

Category

UK Arisings Data

2010

Brominated

plastics in

waste

(Empa)1

No.

Samples

Mean

PBDE UK

samples

Weight Stockholm listed

PBDEs UK WEEE (tonnes)

tonnes % % mg/kg Best

estimate

Lower

limit

(5%ile

Upper

limit

(95%ile)

Large household

appliances 141,236 31.0 0.29 6 762.2 0.312 0.067 0.817

Small household

appliances 22,870 5.0 0.75 1 57.4 0.003 0.001 0.009

Fridges 97,414 21.0 10.0 1 39.3 0.010 0.003 0.022

ICT & consumer

electronics 186,435 40.0 18.0 9 3140.2 123 53 242

Other waste (not

sampled) 13,265 3.0

Total 461,220 100.0

Note:

Single pieces from 6 items. Bulk sample from multiple shredded units. Empa do not provide a figure for the level of brominated plastics in cooling appliances, WRc have assumed that it is higher than other large household appliances due to the plastic internal construction of a fridge or freezer but less than ICT where the outer frame consists of brominated plastic.

Secondly, the sampling approach was developed on the working assumption that X-Ray

fluorescence spectrometry screening would show that the majority of plastic pieces (each

representing a unit) would not contain PBDEs and that certain waste streams could be excluded

from the gas chromatography mass spectrometry (GCMS) analysis. This would have meant that a

larger number of samples could be tested within selected component waste streams to increase

certainty in the range data produced. In the event the screening showed that the majority of the

data shows that that there was detectable contamination across all target waste electrical and

electronic equipment and it was therefore necessary to spread the available GCMS testing

resource across all component streams. The range of data for each congener group is wide and

the number of samples in each category smaller than was originally intended and this hinders any

attempt to estimate the quantities of PBDEs in the overall UK waste stream with acceptable

certainty. Specifically the estimates of listed PBDE in UK waste electrical and electronic equipment

would be substantially improved if the number of samples in each category is increased by further

1 Empa (Swiss Federal Laboratories for Materials Science and Technology ). Empa: http://ewasteguide.info/introduction/e-waste

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sampling and testing to allow the corresponding distributions of PBDE concentrations to be

estimated: i.e. confirmation of lognormality, and summary statistics including the mean, variance

and upper and lower percentiles.

Levels of PBDEs in End of Life Vehicles: Samples will be collected in January 2012 to address

the gap in new data for end of life vehicles. Data will be reported to Defra as a supplementary Annex to

this report.

PBDE Quantification by High Resolution Gas Chromatography Mass Spectrometry: A

PBDE test method was developed to support this programme of work. Despite extensive method

development the determination of PBDEs in plastic and foam matrices continues to be a challenge

although a UK laboratory is now in a position to test for target PBDEs in the plastic from waste electrical

and electronic equipment. However, the technique requires a specialist laboratory, a multi-stage

sample preparation and extraction procedure and high resolution gas chromatography mass

spectrometry to test the final sample. The method is capable of determining sub 0.05 mg/kg of

individual PBDE congeners in waste electrical and electronic equipment plastics, but the complexity,

and cost of the test, means it is not a tool that is applicable to routine process monitoring. This may also

have implications for regulatory monitoring of PBDEs. The analytical methodology used to undertake

analysis of plastic samples by Marchwood Scientific Services has been optimised for the determination

of PBDEs in plastic materials. The use of labelled internal standards allows concentration of PBDEs to

be determined using internal standardisation which allows recovery correction of PBDE data. This

approach eliminates the need for correction equations (or recovery factors), and is an established and

widely applied in a wide range of analytical applications. The method requires the assessment of PBDE

recovery from a matrix sample to provide full method validation (a ‘blank’ or low PBDE plastic reference

sample could not be obtained within the timeframe of the method development activities but this will be

addressed if further testing is required). Criteria for acceptance of calibration samples (including a

standard reference material) and internals standard recovery have been agreed for future testing. A

small interlaboratory comparison exercise indicates acceptable data comparability between the new

method and test data generated by a European test facility which has considerable experience of

testing WEEE matrices.

Suitability of X-Ray fluorescence spectrometry as a screening tool: X-Ray fluorescence

spectrometry provides a rapid technique for the assessment of total bromine in end of life vehicles and

waste electrical and electronic equipment. Any limitations in the technique arise from the fact that it

cannot distinguish between PBDEs and other bromine containing compounds or determine which

PBDEs are present in the sample i.e. whether the PBDEs listed in the annexes of the Stockholm

Convention on Persistent Organic Pollutants are present. This aside with the exception of printed circuit

boards which are known to contain tetrabromobisphenol A, the correlation between X-Ray fluorescence

spectrometry data and GCMS indicates that PBDEs appear to be the primary bromine containing

compound in other waste electrical and electronic equipment. Many of the samples tested provide low

<100 mg/kg total bromine but this could be consistently linked to low concentrations of listed PBDEs,

Such low concentrations of PBDE have little value as flame retardants and it is concluded that this is

consistent with recycling of listed PBDEs in the waste plastic stream into new products. Conversely

where bromine concentrations exceeded 1% w/w whilst the majority of this could be attributed to non-

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listed PBDEs that are legitimately being added during manufacture low levels of listed PBDEs are also

present. We conclude that X-Ray fluorescence spectrometry can be used as a crude but effective

screening tool to identify waste electrical and electronic equipment and end of life vehicle residues

containing bromine and potentially PBDEs. The results of this relatively limited study suggest that a

positive X-Ray fluorescence spectrometry bromine result provides a good indicator measure for the

presence of listed persistent organic pollutants. In particular very low total bromine concentrations

(<500 mg/kg) are often linked specifically to listed PBDEs.

iv Proposals for further work

The authors suggest that the precision associated with PBDE concentrations in the current dataset

could be improved with further analysis of the available sample bank collected for this study. This

should focus on the apparently high levels of hepta-BDE in all waste electrical and electronic

equipment streams.

Further sampling and testing should be targeted at:

establishing with further certainty the profile of PBDE concentrations in each

component and sub-component category; and

waste streams which exhibit the widest concentration ranges and which represent high

volume waste streams to improve both the weighted average and reduce uncertainty in

any grossing up estimates.

A detailed breakdown of UK waste electrical and electronic equipment arisings is required at a

finer level than currently published Environment Agency data to allow derivation of grossed up

averages of PBDEs in the total waste stream. Further data is required on the percentage

contribution of the hard plastic components to the total weight of each unit to further improve the

accuracy of any grossing-up activity.

v Résumé of Contents

Section 1 and 2 provide background to the project and the approach taken to sample collection and

testing. Section 3 presents summary test data for both X-Ray fluorescence spectrometry screening and

laboratory testing of waste electrical and electronic equipment. The conclusions from this work and

findings regarding the PBDE content of the UK waste electrical and electronic equipment waste stream.

Appendix A provides a summary of the method development work undertaken to enable the testing of

PBDEs in plastics and Appendix B provides the X-Ray fluorescence spectrometry and gas

chromatography with mass spectrometry test data by PBDE congener.

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1. Introduction

1.1 Overview

Polybrominated diphenyl ethers (PBDEs) have been in use as flame retardants in plastic and

foam items within electrical and electronic equipment and motor vehicles since the 1970s, and

as such will be present in the waste stream of these products when they are discarded. There

are a total of 209 PBDE congeners, which are categorised into 10 groups on the basis of their

level of bromination, using a pre-fix i.e. tri-, tetra-, penta-, hexa-, hepta-, octa, nono- and deca-

BDE.

As part of implementation of the Persistent Organic Pollutants Regulation (Regulation

850/2004/EC) the EU intend to set limit values for new substances (newly listed) added to the

annexes of the Stockholm Convention on Persistent Organic Pollutants (2009) for specific

waste streams which include waste electrical and electronic equipment (WEEE) and end of

life vehicles (ELV). The impact of such limit setting on UK business is unclear as the data on

PBDEs levels in these waste streams is sparse.

Newly listed substances include the fire retardants tetra- penta-, hexa- and hepta-BDEs.

Although their use in EU product manufacture has been restricted within the EU since 2003-4,

they may still be present in items within WEEE and ELV that are manufactured outside of the

EU or that incorporate plastic recyclate that contains listed PBDEs.

This report details the information collected through a Defra funded project to generate new

data on the ranges of PBDEs found in United Kingdom (UK) WEEE and ELV to support Defra

in the implementation of the Persistent Organic Pollutant Regulation. Data on the PBDE

content of the plastics and foam components of waste electrical and electronic equipment and

end of life vehicle residues requires some further refinement, although this study provides an

initial measure of the concentration ranges of PBDEs that might be expected in these waste

streams.

Method development was required to ensure that quantification of the PBDE content was

sufficiently robust to enable informed decisions to be taken about limits that could be

implemented within the EU.

WRc collected samples of different WEEE arisings from a number of UK collection and

reprocessing sites to assess the degree of contamination of listed substances PBDEs in the

overall UK waste stream. Access to the ELV waste stream will be achieved in December 2011

and new data will be produced for this stream.

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1.2 Objectives

To derive statistically sound estimates for PBDEs present in a wide-range of UK WEEE

and ELV waste-streams, using sensitive laboratory GCMS (Gas Chromatography with

Mass Spectrometry) analysis.

To determine the suitability of XRFS (X-Ray Fluorescence Spectrometry) for the

screening of WEEE and ELV wastes for PBDEs. Such screening may have value in

providing a means to separate high PBDE waste streams prior to re-processing and

facilitate removal of contaminated material from the reprocessed stream.

1.3 Background

Polybrominated diphenyl ethers are additive brominated flame retardants i.e. they are not

blended into the matrix and as such may be available for leaching from products and wastes

and therefore move into the wider environment. There are a total of 209 PBDE congeners,

which are categorised into 10 groups on the basis of level of bromination, with a pre-fix

referring to the level of bromination i.e. tri-, tetra-, penta-, hexa-, hepta-, octo-, nono- and

deca-BDE.

The current Defra study is focused on determining the levels of Stockholm listed POPs tetra,

penta-, hexa- and hepta-BDEs in selected waste streams. However, it was important to

determine the concentrations of other congeners because:

commercial ‘C’ formulations of the flame retardants nominally comprising one congener

group level are often a mix of congeners. For example, the main constituents of C-

Penta are 28-35% tetra BDE-47 and 44-51% penta BDE-99 and 100 in addition to

much smaller concentrations of tetra BDE-49 and -66, penta BDE-85, hexa BDE-138, -

153 and -158. C-Octa contains predominately octa BDE-203 and hepta BDE-183, but

up to 14% hexa BDE-153, 10% nona BDE-206 and trace levels of hexa BDE 154,

penta BDE-99 and tetra BDE-47. C-Deca which is not a Stockholm listed formulation

consists of >98% deca BDE-209. The exact composition of commercial formulations

vary. A single unit e.g. a fridge can contain components from a range of suppliers which

contain varying levels of PBDEs.

data produced using the portable XRFS can be compared with laboratory GCMS data

to assess its value as a screening tool. XRFS provides a measure of ‘total’ bromine in a

sample i.e. inorganic and organic species.

C-Penta BDE products are commonly added to polyurethane foams used in mattresses,

upholstered furniture and carpet padding. C-Octa BDE products are added to acrylonitrile-

butadiene- styrene (ABS) used in computer and appliance casings. C-Deca BDE is the most

widely used PBDE in the global market and is added to polystyrene, polypropylene and other

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thermoelastic polymers used in adhesives, insulation as well as casings for televisions and

computers.

1.4 Total UK WEEE and links to brominated plastics

The Environment Agency report that approximately 460 000 tonnes of WEEE was collected in

the UK in 20102. This predominantly comprised:

large household appliances (washing machines, dishwashers and electric cookers) at

31% by weight of the total;

cooling appliances (fridges and fridge freezers) at 21% of total weight; and

display equipment (televisions and computer monitors).

Arisings data for UK WEEE is provided in Table 1.1.

Table 1.1 UK Waste electrical & electronic equipment (WEEE) collected in 20101

Category Name Total separately collected

household WEEE

Proportion

(%)

Large Household Appliances 14,1236 31

Small Household Appliances 22,870 5

IT and Telecoms Equipment 29,548 6

Consumer Equipment 27,150 6

Lighting Equipment 0.4 0.0001

*Electrical and Electronic Tools 10,661 2

*Toys, Leisure and Sports 1,286 0.28

*Medical Devices 10 0.0022

*Monitoring and Control Instruments 606 0.13

*Automatic Dispensers 0.0 0.00

Display Equipment 12,9737 28

Cooling Appliances Containing Refrigerants 97,414 21

*Gas Discharge Lamps 701 0.15

Total 46,1220 100

Note: * Not sampled as part of this sampling programme, but the total weight of these streams represents 2.6% of

the total waste stream).

2 Environment Agency (2011) Waste electrical and electronic equipment UK data reports

http://www.environment-agency.gov.uk/business/topics/waste/111016.aspx

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The plastics fraction in WEEE varies between 10 to 40% of the total unit weight.

Empa (Swiss Federal Laboratories for Materials Science and Technology )3 have produced

data on the percentage of brominated plastics (PBDE, TBBA and PBB) in WEEE. This data

has been used to produce grossed estimates of PBDEs in UK WEEE in conjunction with the

data in Table 1.1.

Some assumptions have been made to align the two sources of information (Table 1.2).

Table 1.2 UK Waste electrical & electronic equipment (WEEE) collected 20101

Category Name Sub-categories

%

brominated

plastics,

% UK WEEE

stream

Large Household Appliances

Cookers, dishwashers, tumble dryers

0.29 31%

Small Household Appliances

Microwaves, kettles, toasters, hoovers,

0.75 5%

ICT and consumer electricals

PC monitors, TV’s, industrial IT equipment

18.0 40%

Cooling equipment Fridges and freezers 10.0 21%

Note:

percentage of the weight of an individual unit.

brominated plastics include PBDE, TBBA and PBB.

Empa do not provide a figure for the level of brominated plastics in cooling appliances, WRc have

assumed that it is higher than other large household appliances due to the plastic internal construction

of a fridge or freezer but less than ICT where the outer frame consists of brominated plastic.

This data has been used in conjunction with the test data from this programme for each of

these component categories to estimate the quantities of PBDEs in UK WEEE in Section 4.2.

3 Empa: http://ewasteguide.info/introduction/e-waste

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2. Sampling and Testing

2.1 Sampling

2.1.1 Development of sampling plan

The aim of the sampling programme was to collect samples that encompassed as many

common waste fractions as was possible, to provide an indication of common contaminant

concentration ranges. This dictated that the sampling approach required collection of multiple

samples of similar waste streams ensuring that sampling encompassed the range of

applications of PBDEs in WEEE and ELV.

A sampling plan was developed that followed the elements outlined in BS EN 14899 the

European framework standard for the sampling of wastes developed by CEN TC 292 Waste

Characterisation. The sampling approach was documented to allow future sampling activities

to be consistent with the current programme.

It was assumed that the production of WEEE and ELV is a UK wide activity and that the type

of waste and PBDE content of that waste would not be different by UK location. Sampling

effort was therefore focussed on the collection of samples from randomly selected ‘larger’

reprocessing sites that tend to accept a wider range of waste types rather than taking a small

number of samples from a large number of re-processors.

A higher proportion of samples were collected of shredded ‘single component’ WEEE rather

than whole single items. This approach ensured that the majority of samples were spot

samples taken from a large number of shredded units and the resulting test data is believed to

be a good representation of the wider UK waste stream.

2.1.2 Sampling exercise

Single visits were undertaken to a range of facilities which collect and bulk or shred, public

amenity waste collection sites and facilities that accept and reprocess shredded waste

streams. This approach provided a snap-shot (or spot samples) of the characteristics of these

wastes during February and March 2011.

The final sampling rationale was agreed following a meeting with Defra and is identified in

Figure 2.1. It was not possible to gain access to representative samples of ELV wastes during

the initial phase of testing and in the time frame of this report. However, a source of suitable

ELV samples has now been identified and sampling and testing are planned for

February/March 2012, the data from which will be reported in an Addendum to this report. The

samples collected were representative of two types of WEEE:

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‘Whole WEEE‘ - single whole components from WEEE awaiting re-processing – in this

instance the whole component e.g. an electronic razor or washing machine door catch

was prepared for testing; and

‘Shredded WEEE’ – single component waste from a generic WEEE category

e.g. casings from washing machines and videos where the component has been

separated and mixed for shredding. The samples from this stream represent pieces

from multiple items within the specified category.

Samples of WEEE were collected from four reprocessing sites as shown in Table 2.14.

Table 2.1 Details of samples collected for PBDE testing

Site Treatment type Materials Number of

samples

Date

sampled

Site A WEEE plastics TVs/ Computers/ small mixed WEEE/

and consumer items (e.g. coat-

hangers)

45 17/2/11

Site B Large WEEE/ELV

segregation

Printed circuit boards 20 22/2/11

Site C Small WEEE Computer equipment and telephones 10 23/2/11

Site D WEEE reuse/

reprocessor

White goods and small WEEE 25 8/3/11

By analysing whole components it was possible to establish the specific levels of PBDEs

associated with single items and specifically the proportions of different congeners. However,

analysis of single components is of limited use for assessing the levels of PBDEs in the UK as

a whole as a large number of items would need to be tested to obtain representative data.

Testing of shredded WEEE will provide such data. The shredded WEEE was commonly

stored in large bags or heaps that are a random snap-shot of the consumer waste streams

comprising more than 100 units. The shredding process serves to mix these components and

the incremental sampling procedure employed ensured a representative sample from the

primary heap. Preparation of the whole sample ensures the test data provides a reliable

average of the primary sample and larger number of units and increases confidence in

subsequent estimates about the wider population. This approach prevents range data being

gathered on an individual sample basis but allows estimation of a more reliable mean to be

derived for the number of samples taken.

4 WRc are currently arranging access to an ELV (polyurethane foam, textiles and ASR plastic)

reprocessing site to collect a range of samples, testing will be carried out using existing budget and

results will hopefully be available in early February 2012.

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Figure 2.1 Sampling approach for PBDEs in WEEE and ELV

Screen on site using XRF to determine which waste inputs

and output streams contain bromine – identify high, medium

and low items/streams

Confirm process inputs and priority process outputs during site

visit with process operators (to ensure information is accurate)

Submit 100 samples to primary contract lab for fine grinding

Submit draft final report to Defra

Stream 1 Stream 2 Stream X

Screen all samples on-site using XRF and select sub-set of

samples on-site for laboratory screening and testing

Select samples for laboratory testing on the basis of XRF

screening (high, medium, low Br) and sample source

Shredded single component WEEE Whole WEEE

Obtain figures on total tonnages of each WEEE waste stream

to derive the proportion of waste contaminated with PBDEs

figures for average and range of PBDEs in England and Wales

Collect and label whole items of single component WEEE.

Samples of shredded single component WEEE consisted of

at least 5 increments from either a falling stream on an

hourly basis over a 4 hour period or by taking at least 5

increments from a storage container

Commentary and justification of approach

Site Visits to collect wide range of WEEE

Determine range data for PBDE data

Identify range of

WEEE items

Plants selected to provide comprehensive range of WEEE. On-site discussion used to identify range of inputs and priority waste streams handled at each site with mass flow data where appropriate.

Screen all input and output field samples using triplicate XRF

measurements

Whole and shredded waste plastic and foam screened using portable XRF to identify detectable Br. On-site screening and sampling was focussed on waste items/streams with higher concentraions of Br as these wastes have the greatest impact on the variability of the final estimated mean PBDE concentrations. Where appropriate the age or serial numbers of high Br input items were noted. On-site screening was undertaken on approximately 300 samples using a single 30 second scan. All samples were returned to WRc.

Whole WEEE: selected low and high Br ‘whole components’ were collected for detailed screening at WRc (where possible individual components were tested separately to identify the source of Br). Selected components were sent to the test laboratory. Good laboratory practice was employed to ensure that the sample integrity was maintained.

WRc on-site activities

Shredded WEEE: Incremental samples were separately bagged for on-site screening and more intensive analysis at the WRc laboratory. A total of circa 100 samples would be returned to WRc using the XRF screening data to provide a range of Br concentrations. All bagged samples were screened in triplicate using the portable XRF. Those samples that exhibited high variability were un-bagged and selected items within the samples individually tested.

WRc laboratory activities

Greater emphasis will be given to samples with detectable Br concentrations to facilitate estimation of the correlation between XRF and GCMS and improved accuracy in range data for each PBDE group. Whilst the majority of samples were tested by the primary contractor using solvent extraction and High Resolution GCMS, a number were sent to a second test laboratory using Low Resolution GCMS to provide a measure of between laboratory variability (this will include all PUR samples). Testing will be scheduled to allow a basic estimation of between site, and between material variability.

Laboratories would both employ solvent extraction to maximise PBDE recovery. WRc would supply a QA specification to be followed by the test laboratory include use of internal standards, blanks, replicates and spiked samples. This approach will allow quantification of PBDE recovery and estimation of analytical method precision and confidence. PBDE congeners would include as a minimum: BDE-47 (tetra); -99 and -100 (penta); -153 and -154 (hexa); and -175 and -183 (hepta) as required by the Stockholm Convention. Additional congeners that are present C-Penta, C-Octa and C-Deca commercial products that are used in PUR, ABSand HIPS respectively would include: BDE -17 and 28 (tri); -196, -197 and 203 (octa); -206 and -207 (nona); and -209 (Deca).

Reporting

45 samples to be tested using HR-GCMS, in addition 10

samples were sent to a second laboratory for HR-GCMS for

QA purposes

All samples to be prepared at one laboratory to avoid introduction of bias using good laboratory practice to avoid cross-contamination.

Discuss report with Defra and obtain feedback

Submit final contract report to Defra

Activities

Overall Objectives: 1. Identify concentration of Stockholm BDEs by waste arising at national level. 2. Assess the feasibility of using XRF as an on-site screening tool to identify ‘PBDE contaminated’ products.

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The shredded WEEE was commonly <50 mm particle size and approximately 10 increments

were taken from either a falling stream across a five hour time period or at various positions

within a stockpile or holding bag to produce a 1 kg representative sample for testing.

This approach allowed an assessment of the levels of specific PBDE congener groups in both

individual components, and the production of average concentrations by waste stream.

2.2 Testing

2.2.1 XRFS Screening

This project was used to trial the application of XRFS as an on-site screening tool and to

calculate correlations with confirmatory laboratory analysis.

A portable X-Ray Fluorescence spectrometer (XRFS) can be used to provide a semi-

quantitative measure of total bromine in a sample. There are many variables affecting the

sensitivity of this technique which include the smoothness and density of the surface to be

tested, sample heterogeneity and total bromine content. A handheld Niton XL3t 700 unit was

used for this study. The limit of detection of the XRFS spectrometer for bromine is dependent

on the length of time a sample is scanned. A detailed plot to illustrate the change in the limit of

detection (LOD) with scan time is provided in Appendix A. A 30 second scan time provides a

LOD for total bromine of circa 5-10 mg/kg and equates to a detection limit of approximately

10 to 20 mg/kg for bromine containing compounds if we assume the compound contains

approximately 50% bromine (i.e. penta PBDE). The detection limit would be slightly better

with a higher level of compound bromination. The variability within a single piece of moulded

plastic was very low (<10%) and within the error of the spectrometer. The potential limitations

of XRFS include:

background levels of 40 mg/kg bromine have been recorded in many waste streams:

XRFS cannot distinguish PBDEs from other flame retardants containing bromine such

as hexabromocyclododecane (HBCD) dimethyltetrabromobisphenol A (MeTBBPA) and

polybrominated byphenyls (PBB); and

the technique cannot identify the level of PBDE bromination i.e. which congener groups

are present.

Each sample bag was initially scanned six times and an ‘average’ concentration recorded.

The XRFS unit reports concentrations for all elements with an atomic weight greater than

chlorine (therefore carbon, hydrogen and nitrogen are not determined). Instruments have a

pre-set factory calibration, and this was checked before and after use with a standard

reference disk, containing a known amount of bromine in a plastic matrix, supplied with the

instrument. The results for the reference disk remained consistent and within ± 5% of the true

value of the standard over the hire period of the instrument (two weeks). Using a 30 second

scan time the XRFS is capable of processing circa 12 samples per hour and therefore

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provides the opportunity to rapidly screen a large number of samples on-site and use this data

to select suitable samples for either further laboratory scanning or GCMS analysis.

On the basis of this data, selected samples were scanned in detail. Individual pieces of plastic

were scanned in a number of places, and the process completed across the entire sample to

produce a weighted average of the entire bag. Levels of bromine did not vary to any large

extent within each piece of plastic, a single scan was therefore subsequently taken of each

fragment, and this was taken to be representative of the whole piece. A total of 35 individual

components were screened by XRFS. In the samples selected for detail analysis upward of

80 pieces of plastic were scanned.

2.2.2 Sample selection for laboratory analysis

From the primary sample four sub-samples were produced during XRFS screening, according

to the following categories:

less than limit of detection (LOD) (approximately 5-10 mg/kg Br)

>LOD to 1000 mg/kg Br

1000 mg/kg to 5000 mg/kg Br

>5000 mg/kg Br.

These sub-samples provide a measure of within sample variability, which is in effect a

measure of the differences between component units. Whole samples provide a measure of

between sample variability.

Results from the XRFS screening were used to select the sub-set of 55 samples for

laboratory testing. The testing programme was developed to identify and quantify the PBDE

congeners present at both the bag level and for selected individual pieces to quantify the

relative amounts of PBDEs present in terms of the total sample to allow national grossing-up

of the data. Characterising the high and the low fractions separately allowed a more precise

estimate to be derived, and to relate the concentrations back to the original waste material.

2.2.3 GCMS analysis

The determination of PBDEs in WEEE and ELV plastic and foam matrices poses many

challenges. PBDEs are photosensitive and will degrade if exposed to sunlight or UV light and

care was taken to keep the samples stored in the dark as far as is possible. As the samples

have all been in environmental use prior to testing the results represent residual

concentrations of PBDEs in the waste plastics. No single UK laboratory was found that could

undertake the determination of full PBDE congener suites to the required limit of detection

(LOD) in both plastic and foam matrices, although a number have expertise in one or other of

these matrices. UK laboratories either had experience of testing sludge and soil matrices

using high resolution GCMS techniques (which offer the lowest LOD) or they routinely

analysed plastics but with a restricted congener suite and a poor LOD. None of the

laboratories had accreditation to relevant certification bodies for these matrices. The selected

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UK laboratory, Marchwood Scientific Services (MSS) undertook substantial method

development and validation to extend their existing sludge method to both plastic and foam.

The method relies on fine grinding of the sample to <1 mm particle size, followed by a 12 hour

soxlet based toluene extraction. Following vacuum rotary evaporation to reduce the solvent

volume to 1 ml the sample is purified on a 500 mg Silica SPE column and any PBDEs present

in the sample eluted with hexane. The analytical methodology used to undertake analysis of

plastic samples by MSS has been optimised for the determination of PBDEs in plastic

materials. Additionally the use of labelled internal standards allows concentration of PBDEs to

be determined using internal standardisation which allows recovery correction of PBDE data.

The use of internal standards eliminates the need for correction equations (or recovery

factors). This approach to analysis is established and applied in a wide range of analytical

applications. The method is capable of determining sub 0.05 mg/kg of individual PBDE

congeners in WEEE plastics (see Appendix A for full details).

A total of 45 samples were submitted to MSS for PBDE analysis. A further 10 samples were

submitted for analysis to the Fraunhofer Institute in Germany who have considerable

experience in testing these types of material to provide method comparison. All samples were

prepared by MSS. The test samples consisted of processing whole bag samples, processing

the sub-samples of the four bags of differing bromine concentrations produced during XRFS

scanning as detailed in Section 2.1.1 and finally specific individual pieces of plastic taken from

these bags. MSS took each of these samples and produced a fine ground powder from the

entire sample. The use of a specialist grinder (see Appendix A section A2.2 for details) to

undertake sample preparation avoided the production of excessive heat which can lead to

melting of the sample and degradation of PBDEs. Prepared samples were stored in dark

bottles to limit photo-degradation. The Fraunhoffer Institute confirmed that the appearance,

odour of the sample and PBDE fingerprints obtained on testing were consistent with samples

that had been appropriately prepared.

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3. Results

3.1 Introduction

The sampling programme targeted the main categories of waste electrical and electronic

equipment (WEEE) generated in the UK. Within the timeframe of the project it was not

possible to obtain samples for some of the minor categories of WEEE (see Table 1.1) or

arrange access to representative ELV waste streams. The samples collected and tested

account for >97% of all household WEEE produced in the UK. The samples collected from

selected collection and re-processing facilities are believed to provide a representative cross

section of WEEE waste being generated UK wide. The screening and analytical test data

therefore provides a useful initial data base on the concentration of PBDEs in UK WEEE.

XRFS: The XRF analysis was used to identify bromine containing waste which might be

indicative, of PBDE contaminated waste. Results are presented first from the XRF

screening in Section 3.2.

GCMS: Following selection of ‘bromine containing’ samples using XRFS, high

resolution GCMS was used to quantify the concentrations of specific PBDE congeners

in the sample. There are 209 possible congeners of PBDE compounds and reference

standards are not available for all of these. In line with standard practice target

congeners were chosen for this test programme for each of the brominated groups on

the basis that they are either widely accepted as being indicator compounds of the

common commercial preparations or they are known breakdown products from

commercially used PBDEs (e.g. nona-BDE is a breakdown product of deca-BDE). The

target congeners identified were matched to those commonly used in a range of

commercial C-Penta, C-Octa and C-Deca products. With the exception of octa-, nona-

and deca-BDEs the analytical suite included more than one congener for each PBDE

bromination group, reflecting those used in commercial products to provide a reliable

estimate of the ‘total’ PBDE concentration for each bromination group based on the

sum of the concentrations of only specified congeners. Table 3.1 lists the PBDEs

selected for testing. Results for the GCMS analysis are presented in Section 3.3.

3.2 XRFS screening

A portable XRFS can be used as an indicative and rapid screening tool to identify bromine

containing compounds. The XRFS provides a reliable measure of whether a sample contains

bromine. It cannot distinguish between inorganic and organic bromine, the type of brominated

compound (e.g. tetrabromobisphenol A (TBBPA) used in printed circuit boards or PBDE) or

differing levels of bromine substitution. The presence of bromine can, however, be used as an

indicator for the possible presence of PBDEs.

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Table 3.1 PBDE congeners analysed in GCMS analysis

Number Group Name

17 Tri 2,2',4-Tribromodiphenyl ether

28 Tri 2,4,4'-Tribromodiphenyl ether

47 Tetra 2,2',4,4'-Tetrabromodiphenyl ether

66 Tetra 2,3',4,4'-Tetrabromodiphenyl ether

71 Tetra 2,3',4',6-Tetrabromodiphenyl ether

85 Penta 2,2',3,4,4'-Pentabromodiphenyl ether

99 Penta 2,2',4,4',5-Pentabromodiphenyl ether

100 Penta 2,2',4,4',6-Pentabromodiphenyl ether

128 Hexa 2,2',3,3',4,4'-Hexabromodiphenyl ether

138 Hexa 2,2',3,4,4',5'-Hexabromodiphenyl ether

153 Hexa 2,2',4,4',5,5'-Hexabromodiphenyl ether

154 Hexa 2,2',4,4',5,6'-Hexabromodiphenyl ether

175 Hepta 2,2',3,3',4,5',6-Heptabromodiphenyl ether

183 Hepta 2,2',3,4,4',5',6-Heptabromodiphenyl ether

190 Hepta 2,3,3',4,4',5,6-Heptabromodiphenyl ether

203 Octa 2,2',3,4,4',5,5',6-Octabromodiphenyl ether

206 Nona 2,2',3,3',4,4',5,5',6-Nonabromodiphenyl ether

209 Deca Decabromodiphenyl ether

3.2.1 Whole WEEE – single component, single item

A range of selected electrical components were screened using the XRFS unit to determine

total bromine content. Over 300 different components were tested. The results of the XRFS

analysis are summarised in Figure 3.1. The results represent single samples of each of the

components and provide a crude snapshot of these waste streams.

The large majority (74%) of hard plastic components screened had a concentration of

<100 mg/kg bromine, with many components containing <20 mg/kg bromine. A small number

(12%) had a very high concentration of total bromine of up to 150,000 mg/kg (15% w/w). The

large range of bromine concentrations leads to an overall average of 11 000 mg/kg bromine,

although 85% of scanned samples had a lower concentration.

The value in this data is to provide a comparison with GCMS PBDE concentrations to assess

the practicality of using XRFS as a PBDE contamination screening tool rather than the

concentrations detected in each item.

The types of components that contained bromine at significant (>1 % w/w) concentrations

tend to be plastics associated with electrical components (covers, printed circuit boards,

switches etc.). These levels are presumed to be indicative of primary PBDE added at the

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0

10

20

30

40

50

60

70

Fre

qu

en

cy

Bromine concentration (mg/kg)

point of manufacture, at levels which commonly exceed 5%. A number of materials contained

medium levels of bromine, this is thought to be associated with PBDEs added during the

manufacture of new products in process that utilise recycled plastics containing PBDEs.

Figure 3.1 Concentration of bromine in selected electrical components by portable

XRFS unit

Results of scanning over 300 individual components of WEEE from large household appliances, refrigerators and

small WEEE

3.2.2 Shredded WEEE – single component, multiple items

Detailed scanning has identified a typical fingerprint for XRFS bromine in shredded WEEE. A

typical histogram for shredded plastic from computer monitor casings is provided in Figure 3.2

for scan results on individual pieces in sample A17. This data is typical of that produced for

other waste streams. Many of the plastic pieces show two distinct concentration ranges 1).

less than 500 mg/kg and 2) >5000 mg/kg bromine. The greatest proportion of readings was

found in the first group with the majority of readings at much lower levels, some 66% around

5 mg/kg bromine. A small number of samples had a very high total bromine concentration of

>100 000 mg/kg. Sixty-six percent of the samples had <10 mg/kg total bromine. Analysis of

the data for individual samples shows that whilst the average bromine concentration for this

sample was 15 000 mg/kg, this is influenced by a small number of plastic pieces that had

extremely high values.

Although the average concentration is an important outcome of the testing, to test the

usefulness of XRFS as a screening tool test samples were split into indicative bromine

concentration ranges, as described in Section 2.2.1 and the categories generated were then

analysed by GCMS to provide a comparison between the two techniques. Sample A17 was

tested in this way. The XRFS and GCMS data are presented in Figures 3.2 and Figure 3.3.

These sub-samples provide a measure of within sample variability, which is in effect a

74% very low total bromine

14% medium total bromine

12% high total bromine

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measure of the differences between component units. Whole samples provide a measure of

between sample variability. The high level of within sample variability shows the importance of

robust sampling procedures for these waste streams.

Figure 3.2 Plot showing range of concentrations of Br in samples of computer

casings by XRFS

3.3 GCMS analysis

The analytical methodology used to undertake analysis of plastic samples by MSS has been

optimised for the determination of PBDEs in plastic materials. Additionally the use of labelled

internal standards allowed concentration of PBDEs to be determined using internal

standardisation which allows recovery correction of PBDE data. The use of internal standards

eliminates the need for correction equations (or recovery factors). This approach to analysis is

established and applied in a wide range of analytical applications. The method developed by

MSS for the determination of PBDEs in plastics requires the assessment of PBDE recovery

from a matrix sample to provide full method validation (a ‘blank’ or low PBDE plastic reference

sample could not be obtained within the timeframe of the method development activities but

this will be addressed if further testing is required). Criteria for acceptance of calibration

samples (including a standard reference material) and internals standard recovery have been

agreed for future testing.

Five samples were tested by both MSS and the Fraunhofer Institute in an interlaboratory

comparison trial to judge the validity of the new test data (Appendix B4). The test data for

sample S10 ‘High’ showed poor correlation between the two laboratories and this could be

0

5

10

15

20

25

30

0 5 20 500 1000 5000 100000 200000 More

Fre

qu

en

cy

Br concentration (mg/kg)

Medium (11%) Low (66%) High (23%)

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attributed to sample heterogeneity at even the small particle scale (XRFS analysis indicate a

wide range in concentrations between individual plastic pieces in this sample). Results from

MSS are also consistently higher than Fraunhofer’s for three congeners: 183, 154 and 100.

However, if these three congeners and the S10 ‘High sample’ are excluded, there is a fair

measure of agreement between the laboratories (Table B.8).

The most prevalent congener of PBDE found in all test samples was deca BDE-209, which

accounted for 85% of all PBDEs detected. Deca BDE-209 is not a listed Stockholm

compound. This does mean that XRFS screening could give false positives where the

presence of bromine is used as a presumptive indicator for listed PBDEs.

3.3.1 Whole WEEE – single component, single item

Components that did contain significant levels of bromine using XRFS were submitted for

analysis by GCMS, to quantify concentrations of PBDEs. The results are summarised in

Figure 3.3. The sum of the target congeners selected for this programme, which are those

predominately used in commercial formulations have been used to provide a measure of the

total concentration of each listed brominated BDE group.

Figure 3.3 PBDE concentrations in various whole electrical components taken from

UK waste sites

The blue diamonds represent calculated total PBDE concentrations for each congener suite

for each WEE category. The concentrations for each WEEE category should be taken from

the right hand axis and are in decreasing concentration of total PBDE from left to right. The

histogram style bars illustrate the proportion of individual PBDE groups in terms of the total,

as measured by the sum of the each target congener suite. The proportions of each congener

0

10000

2000030000

4000050000

60000

7000080000

90000

0.0%10.0%20.0%30.0%40.0%50.0%60.0%70.0%80.0%90.0%

100.0%

Tota

l PB

DE

(mg/

kg)

Pro

po

rtio

n P

BD

E co

nge

ne

r

deca

nona

octa

hepta

hexa

penta

tetra

tri

Total PBDE

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are presented on the left hand axis. For example, a TV unit contained over 83,820 mg/kg total

PBDE which consisted of 5.8% (4800mg/kg) hexa, 27.4% (23,000 mg/kg) hepta, 5.1% (4300

mg/kg) octa, 0.9% (720mg/kg) nona, 60.7% (51,000) deca PBDEs. The raw data on PBDE

concentrations in individual samples is provided in Table B.2 in Appendix B.

The data are for single examples of each WEEE component type and should not be

considered to be representative of UK waste arisings but are useful to illustrate the

differences in congener groups and total PBDE concentrations in different WEEE categories.

The dominant PBDE congener is clearly deca-BDE (as measured by deca-209), which is still

in legitimate use. Only one sample from a TV casing contained significant levels of hepta- and

octa-BDE groups. This sample also contained high levels of deca-BDE (87% of the total

PBDE concentration). This observation is consistent with data for shredded WEEE. The

GCMS data provides sound evidence that mixes of PBDE congeners and bromination groups

are used in components rather than one specific congener. Low levels of ‘listed PBDEs were

seen in all samples. This low level contamination could be attributed to the proportion of

recycled plastic in the component tested. Of the 45 samples of whole and shredded samples

tested, none contained below detection limit levels of Stockholm-listed PBDEs.

3.3.2 Shredded WEEE – single component, multiple items

The GCMS data confirms that XRFS is effective in identifying component pieces within a

waste stream that contain bromine. In the majority of samples then tested by GCMS

detectable XRFS bromine could be matched to quantifiable levels of PBDEs in WEEE items.

Low XRFS bromine could be specifically linked to low PBDE concentrations by GCMS and

specifically listed PBDEs. Figure 3.4 illustrates the differing concentrations of PBDEs in a

single sample prepared from a large number of pieces of computer cases from multiple units.

The PBDEs in the shredded components are dominated by nona- and deca-BDE congeners.

Ten samples were submitted for GCMS testing each consisting of circa 80 pieces from

different units. The samples are therefore considered to be representative of the wider UK

waste stream.

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Figure 3.4 Plot showing PBDE concentrations in a bulk sample of shredded

computer casings

Figure 3.5 provides the same data but excludes nona- and deca-BDEs. Although the ‘high’

sample still has the largest proportion of BDEs, the difference in concentrations of the other

PBDE bromination groups is much less marked. The ‘high’ sample has over 1000 times the

concentration of total BDEs compared to the ‘low’ sample, whereas it only has four times the

concentration of BDEs that are not nona- or deca-. This would seem to indicate that these

groups are present due to the addition of recycled plastic waste containing non nona- or deca-

PBDEs rather than they have been added at percentage levels to provide flame retardant

properties. GCMS concentration data by PBDE congener is provided in Table B2 in

Appendix B.

0

2000

4000

6000

8000

10000

12000

14000

16000

A17 High A17 Medium A17 Low

Tota

l PB

DE

(mg/

kg)

deca

nona

octa

hepta

hexa

penta

tetra

tri66% 11% 23%

Very small

proportion of

PBDEs that are

not nona- or

deca- BDE in all

three fractions

Defra

WRc Ref: UC8720.05/15613-0 February 2012

© WRc plc 2012 25

Figure 3.5 Plot showing PBDE concentrations in bulk sample (A17) of shredded

computer casings excluding nona- and deca-BDE

Figure 3.6 details the test data for a sample of TV casings, consisting of 80 plus pieces of

different shredded units. Very low levels of PBDE were detected in the medium and low

samples separated by XRFS screening.

Figure 3.6 Plot showing PBDE concentrations in sample (A28) - television casings

0

5

10

15

20

25

30

A17 High A17 Medium A17 Low

PB

DE

con

cen

trat

ion

(m

g/kg

)

octa

hepta

hexa

penta

tetra

tri

tetra seen in medium stream

Difference between

high and low fraction

much less pronounced

Defra

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© WRc plc 2012 26

4. Discussion

4.1 PBDEs in UK WEEE

Samples collected for this study represented the following categories of WEEE: large

household appliances, lighting equipment and small household appliances (all single items

from single units only), IT and telecoms equipment, consumer equipment, display equipment

and cooling appliances containing refrigerants. These categories represent 97% of the total

weight of WEEE collected in the UK (Table 1.1)5. Range data for the indicator PBDE

congeners is presented in Table 4.1. In deriving range data the test data has been assumed

to be log-normally distributed, which is supported by the data analysis in Appendix B3.

Table 4.1 Unweighted range data (GCMS) for PBDEs Waste electrical and electronic

equipment (WEEE)

Material No.

Range data for PBDEs for WEEE categories (mg/kg)

tri tetra penta hexa hepta octa nona deca

TVs 7 <0.001 -

21

0.005 -

2100

0.01 –

4410

0.03 -

14000

0.1 -

36500

<0.001 -

1880

<0.001 -

901

21 -

138000

Industrial IT

equipment 5

0.0029 -

25.4

0.0002 -

254

0.0004

– 435

0.001 -

1210

0.0047 -

5960

<0.001 -

47.7

0.0106 -

625

0.162 -

32400

Printed circuit

boards 2 1.3 - 2.4

5.93 -

11.2

6.97 –

16

307 -

582

2790 -

5230

<0.001 -

173

268 -

638

42500 –

129000

Digiboxes 4 0.0002 -

2.28

<0.001 -

215

0.0035

– 462

0.009 -

1470

0.03 -

4990

<0.001 -

1690

<0.001 -

288

4.4 –

5720

Large

household

appliances

13 0.0005 -

6.5

0.0071 -

14.2

0.042 –

65

0.138 -

308

0.178 -

3850

<0.0005

- 426

<0.0005

- 790

912 -

45700

Small WEEE 1 0.37 3.2 5.1 8 41 5.43 5.51 778

Coat hangers

4 0.002 -

0.76

0.03 -

3.45

0.06 -

5.61

0.1 -

74.9

0.725 -

3440

<0.001 -

645

0.1 - 288 22 –

80400

Fridges 2 0.3 - 0.5 0.5 - 3.2 1.6 - 4.5 11 - 14 <0.001 -

44.5 4.2 - 6.4

12.2 -

28.3 79 - 155

PC monitors 4 0.01 -

0.08

0.129 -

0.556

0.209 -

1.05

0.8 -

3.07 4.7 - 20

<0.001 -

2.79

0.163 -

490 6 - 13900

Stockholm Annex listed PBDEs

5 The 3% of WEEE not captured in this study includes electrical and electronic tools, toys, leisure and

sports; gas discharge lamps; monitoring and control instruments; medical devices; lighting

equipment; and automatic dispensers.

Defra

WRc Ref: UC8720.05/15613-0 February 2012

© WRc plc 2012 27

The table is colour coded by congener – the highest concentration seen for each congener is

coloured red, through orange to green for the lowest concentration. For example, for hepta-

BDEs, the highest concentration was seen for IT equipment, and the lowest for PC monitors.

The data provides an initial estimate of the PBDEs in the UK WEEE waste stream. The

ranges are wide and this is a reflection of high within sample variability and where we have

tested low, medium and high material (as screened by XRFS) separately. This shows the

importance of collecting samples that consist of a large number of shredded pieces and which

are representative of multiple units to avoid bias.

Weighted average PBDE concentrations for each congener by WEEE stream are shown in

Figure 4.1. The concentrations are derived from the weighted average of the GCMS data for

each of the ‘high’, ‘medium’ and ‘low’ fractions (as defined by XRFS screening) as a

proportion of the overall sample to give an overall concentration for each of the categories.

Household appliances have not been included in this plot as data is only available for a limited

number of single pieces from a small number of individual units.

Figure 4.1 Plot showing PBDE concentrations in shredded bulk WEEE samples

As with previous plots the proportion (left hand axis) of each PBDE group is shown by the

bars, and the total concentration of PBDEs (right hand axis) shown by the red diamonds. The

highest concentration of total PBDEs were found in printed circuit boards (PCBs), TVs and IT

equipment. The most frequently detected congener present in the highest concentrations was

209-deca BDE. Significant proportions of hepta-BDE were also seen in TVs, IT equipment

and digiboxes. The number in brackets (x axis) represents the number of samples tested for

each component type. Testing of the ‘low’, ‘medium’ and ‘high’ sub-samples produced from a

single sample is counted as a single sample. Although a relatively small number of samples

were tested in total each sample consisted over 80 pieces and is considered to represent

greater than 100 individual units. Table 4.2 provides this range data in tabular form, the

Defra

WRc Ref: UC8720.05/15613-0 February 2012

© WRc plc 2012 28

ranges are much tighter but overall sample numbers need to be increased to improve data

certainty. Note where only one combined sample has been tested the figure quoted is a

minimum value.

Table 4.2 Weighted range data (GCMS) for PBDEs Waste electrical and electronic

equipment (WEEE)

Material No.

Weighted average range data for PBDEs for WEEE categories (mg/kg)

tri tetra penta hexa hepta octa nona deca

TVs 2 2.5-3.3 6.6-338 13.0-

707

273-

2251

2051-

5852 168-302 145-168

8446-

37419

Industrial IT 1 14.9 149 255 711 3495 9.9 372 21486

Printed circuit

boards 2 1.3-2.4 5.9-11.2 7.0-15.1

307-

582

2785-

5231 0.0-173 268-638

42481-

129045

Large HH

appliances¹ 6 0.0-1.8 0.0-7.4 0.0-30.0

0.1-

310.0 1.0-3800

0.0-

430.0 0.0-180

910-

46000

Digiboxes 1 0.4 25.9 55.5 176 601 203 34.7 855

Small WEEE 1 0.4 3.3 5.1 8.0 41.0 5.4 5.5 778

Fridges 1 0.4 1.8 3.0 12.2 22.2 5.3 20.2

PC monitors 2 0.0-0.0 0.2-0.4 0.3-0.8 1.5-2.6 9.2-13.6 0.8-2.8 15.7-116 3488-

7998

Stockholm Annex listed PBDEs

Note: ¹ 6 items from 6 individual units

Weighted average data for Stockholm listed POPs (tetra-, penta-, hexa- and hepta-PBDEs)

along with total PBDE concentrations are presented in Table 4.3. These concentrations are

derived from the weighted averages of the ‘high’, ‘medium’ and ‘low’ fractions and bulk

samples that were tested as a whole sample.

As in previous tables, the table is colour coded, showing highest concentrations in red,

through orange to green for the lowest concentrations. It can be seen that in general, high

concentrations of total PBDEs are correlated with the Stockholm list of PBDEs. A notable

exception to this is the PC monitor category where the majority of PBDEs present in this

material are nona and deca congeners. Data for large household appliances should be

viewed with extreme caution as it is based on a small number of component parts from

individual units rather than a sample that represents a large number of shredded units

Defra

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© WRc plc 2012 29

Table 4.3 Weighted average concentrations of the sum of Stockholm listed PBDEs

and total PBDEs by WEEE stream

Category Average total tetra, penta,

hexa, hepta- PBDE (mg/kg)

Average total PBDE

(mg/kg)

TVs 5746 90777

Industrial IT equipment 4610 29073

Printed circuit boards 4473 26493

Digiboxes 858 5825

Large household

appliances 762 16945

Small WEEE 57 847

Fridges 39 182

PC monitors 14 12353

Sum of Stockholm listed PBDEs

Sum of total PBDEs

(listed and unlisted)

The key implications of the data for each WEEE category, presented in Tables 4.1 to 4.3 are

summarised in word form in Table 4.4, but the following main conclusions can be drawn:

Listed PBDEs were detected in all WEEE tested, if as we believe, the ‘snapshot’

samples tested are representative of the wider UK wide WEEE stream (each sample is

representative of some 100 units) this points to a widespread issue for future waste

management practice.

The concentrations of listed PBDEs vary substantially by WEEE stream. Fridges, larger

household appliances and PC monitors generally have lower concentrations than TVs,

industrial IT equipment, printed circuit boards and digiboxes.

Defra

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© WRc plc 2012 30

Table 4.4 Summary PBDE data for WEEE

Number Findings

Fridges Concentrations of all PBDEs were quantifiable but lower than in most

waste plastic streams. All Stockholm Annex listed PBDEs were

detected by high resolution GCMS. The levels of deca-BDE were x5

those of the Stockholm list.

Large household

appliances

Although 85% of samples scanned by XRFS contained no or low levels

of bromine, many components from large household waste appliances

were found to contain significant levels of deca-BDE. Some samples

were also found to contain medium levels of hepta-BDEs.

PC monitors The vast majority of BDEs detected by GCMS were deca-BDEs. PC

monitors were found to have medium levels of deca-BDE and low levels

of all other congeners, despite having some of the highest levels of

bromine by XRFS scanning. This raises the possibility that there may

be other brominated flame retardants present in these samples, as

much of the bromine observed in XRFS cannot be accounted for by the

PBDE test data.

TV TV casings contained some of the highest levels of hepta-BDEs and

high levels of many of the lower substituted congeners. TVs had the

highest levels of deca-BDE.

IT equipment High concentrations of most PBDE congeners, with some of the highest

levels of Stockholm list tetra- and penta-BDEs in any waste category.

High levels were found in many different component fractions.

Digiboxes Medium to high levels of PBDEs were observed for most bromination

groups, 11% of all samples had a bromine concentration of >1%. The

observed concentration of the Stockholm list BDEs other than deca

were in the medium range, suggesting they have been added via plastic

recycling as they would be present at much higher concentrations if

they were being added specifically as flame retardants.

Small WEEE Low levels of all BDEs were found in this single sample of WEEE.

Printed circuit

boards

High levels of bromine were found in >95% of samples, much of which

is likely to be present as TBBPA. However, the samples also contained

very high concentrations of nona-, deca-BDEs.

Coat hangers Coat hangers contained medium-low levels of all PBDE congeners.

Very high levels of deca-BDE were found in some samples.

Defra

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© WRc plc 2012 31

4.2 Estimates of PBDEs in UK Waste stream

WRc have used the weighted average data presented in Table 4.3 to calculate estimates of

the total quantities of Stockholm listed PBDEs in the UK WEEE stream, these are presented

in Table 4.5. Published Environment Agency data on UK waste arisings (total tonnes by

specified WEEE categories - Table 1.1) has been combined with the mean concentration

value for PBDEs in each stream (Table 4.4) and data on the percentage of brominated

plastics by total unit weight (Empa - Table 1.2) to produce a gross estimate.

Confidence limits have been estimated for the derived weights of PBDEs in UK WEEE. The

confidence limits assume that samples have been chosen randomly and that the published

data for UK waste arisings and the weight of brominated plastics in consumer items are

correct.

Current estimates of the quantities of listed PBDEs in WEEE suggest that effective measures

for separation of PBDE contaminated components would be most beneficial for large

household appliances and the ICT and consumer electronics category. The data set for large

household items is limited by the fact that the samples tested represent single items from

single units and the sample may not be representative of the wider UK waste stream. The

large weight of total arisings for this waste stream, and potentially high levels of listed PBDEs

associated with some individual components mean that it could provide a substantial

proportion of the total listed PBDEs in UK WEEE. Further sampling is recommended to

reduce uncertainty in PBDE concentrations in this waste stream. Within the ICT stream it has

been necessary to combine TVs and PC monitors which have quite different PBDE profiles

and concentration ranges. A more detailed assessment is required for individual target sub-

categories to provide more reliable estimates of the quantity of listed PBDEs in UK WEEE.

The estimates provided in Table 4.5 are based on a relatively limited number of samples of

UK WEEE (at the aggregated ‘whole’ sample level) and should be used with caution and with

due consideration of the following assumptions and facts.

Estimated percentage weights of brominated plastics versus the total weight of each

WEEE component unit (Empa) are only available for the following gross categories:

large household appliances, small household appliances and ICT and consumer

electronics. In the production of grossed estimates it has therefore been necessary to

assume that the percentage weight of brominated plastics as a proportion of the total

weight remains constant for each of the combined sub-categories (e.g. ovens, tumble

driers, dish washers) within each overall category (large household appliances) etc.

Data on the weight of plastic components containing PBDEs within each sub-category

is required to reduce grossing errors.

Data on the quantity of PBDEs as a percentage of the total weight of brominated

plastics is also not currently available. Brominated plastics include PBDE, TBBA and

PBB, but for the purpose of the current estimation exercise it has been assumed that

Defra

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© WRc plc 2012 32

the quoted weight of brominated plastics (Empa) are all PBDEs. The gross estimate

therefore represents a maximum. Data on the weight of brominated plastics as a

percentage of the total weight of plastic is not available for cooling appliances and it

has been assumed that the weight percentage of brominated plastics is greater than

other large household appliances but lower than ICT and a figure of 10% has been

adopted.

WEEE sub-categories have been combined into four overall categories for which data

on waste arisings and levels of brominated plastics are available. The gross categories

therefore contain a wide variety of materials and components which, on the basis of this

study for Defra can have different levels of PBDE contamination. Waste arisings data

at a more detailed level would improve the accuracy of any estimation of PBDEs in the

UK waste stream.

The sampling approach was developed on the working assumption that X-Ray

fluorescence spectrometry screening would show that the majority of plastic pieces

(each representing a unit) would not contain PBDEs and that certain waste streams

could be excluded from the gas chromatography mass spectrometry (GCMS) analysis.

This would have meant that a larger number of samples could be tested within selected

component waste streams to increase certainty in the range data produced. In the

event the screening showed that there is low level contamination from tetra-, penta-,

hexa- and hepta-BDEs across all target WEEE and that a significant proportion are

present at a higher level of contamination most probably due to mixing of contaminated

recycled plastics in new products and it was therefore necessary to spread the

available GCMS testing resource across all component streams. The range of data for

each congener group is wide and the number of samples in each category smaller than

was originally intended and this hinders any attempt to estimate the quantities of

PBDEs in the overall UK waste stream with acceptable certainty. The accuracy of the

range data is limited by the variability within and between samples and the relatively

small number of ‘whole’ samples tested in each category. Collection of additional

samples in key target categories would improve this situation.

Specifically the overall estimates would be substantially improved if the number of

samples in each category was increased by further sampling and testing, ideally to

make the total number of samples in each category up to 12 to allow the corresponding

distributions of PBDE concentrations to be estimated: i.e. confirmation of log-normality,

and summary statistics including the mean, variance and upper and lower percentiles

to be calculated. There is some scope for reducing the sample numbers down to a

minimum of say eight per material, at the cost of greater uncertainty in the estimates.

Further examination of the test data to further determine the correlations between

congener concentrations, and between the GCMS and XRFS results could be used to

gain the maximum information from sampling and analysis at minimum cost. High

correlations imply scope for analysing a small number of parameters and estimating the

values of other parameters.

Defra

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© WRc plc 2012 33

Within sample variability is high and it is therefore critical that a large and well mixed

sample is collected for analysis to keep differences in the PBDE concentrations of

individual component units biasing the mean.

The total concentration of Stockholm listed PBDEs in each bromination group is based

on summing a relatively small number of indicator congeners, which are present as the

main constituents in commercial PBDE preparations. Low levels of other congeners

may be present and these will not be accounted for using this approach.

The analytical methodology used to undertake analysis of plastic samples by MSS has

been optimised for the determination of PBDEs in plastic materials and the use of

labelled internal standards allows concentration of PBDEs to be determined using

internal standardisation which avoids the need for recovery correction of PBDE data.

Whilst this approach to analysis is established and applied in a wide range of analytical

applications additional quality assurance is required to fully validate the test method.

The test samples and detected levels of PBDEs are considered to be a representative

snapshot of UK WEEE, with the exception of large household appliances and some

individual consumer products e.g. a razor the majority of test sample contain upward of

100 component units.

Defra

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© WRc plc 2012 34

Table 4.5 Estimated weights of Stockholm listed PBDEs in key UK WEEE streams

Waste Category

UK Arisings Data

2010

Brominated

plastics in waste

(Empa)

No.

Sample

Mean PBDE concentrations in UK test

samples (mg/kg)

Estimated wt. Stockholm

listed PBDEs UK WEEE

tonnes % % tonnes tetra penta hexa hepta

Total

Stockholm

listed

PBDEs

Best

estimate

Lower

limit

(5%ile

Upper

limit

(95%ile)

Large household

appliances 141,236 31.0 0.29 410 6 2.9 7.4 63.9 688.0 762.2 0.312 0.067 0.817

Cooling appliances 97,414 21.0 10.0 9,741 1 1.8 3.0 12.2 22.2 39.3 0.010 0.003 0.022

Small household

appliances 22,870 5.0 0.75 172 1 3.3 5.1 8.0 41.0 57.4 0.003 0.001 0.009

ICT & consumer

electronics 186,435 40.0 18.0 33,558 9 71.1 136.5 519.3 2413.4 3140.2 123 53 242

Other waste (not

sampled) 13,265 3.0

Total 461,220 100.0

Note:

Single pieces from 6 items.

Bulk sample from multiple shredded units.

Empa do not provide a figure for the level of brominated plastics in cooling appliances, WRc have assumed that it is higher than other large household appliances due to the plastic internal construction of a fridge or freezer but less than ICT where the outer frame consists of brominated plastic.

Defra

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© WRc plc 2012 35

5. Conclusions and Proposals

5.1 Overview of PBDE congeners in UK WEEE

Consistently low, with respect to flame retardant effect, but detectable levels of listed PBDEs

were seen in all items tested. Since it is believed that these samples are representative of

wider UK WEEE, this equates to widespread listed PBDE contamination across this stream.

The presence of listed PBDEs is usually, but not always, associated with higher and more

variable concentrations of nona-and deca-BDEs. Nona-206 and deca-209 BDEs are the

dominant PBDEs found in both single component waste electrical and electronic equipment

and shredded waste electrical and electronic equipment consisting of multiple components.

Both nona and deca PBDEs are still routinely used as flame retardants in manufacturing, but

neither are listed persistent organic pollutants.

Estimates have been made of the proportion of waste contaminated by Stockholm Convention

listed PBDEs for the UK waste stream (Table 4.5) but these should be viewed with caution for

a number of reasons:

Firstly, data on waste arisings are only available at an amalgamated level for generic

categories e.g. the category ‘display equipment’ contains both TV and PC monitors that

have differing PBDE characteristics. The proportion of the total weight of the PBDE

containing components requires further verification and in some cases this data is not

currently available.

Secondly, the sampling approach was developed on the working assumption that X-Ray

fluorescence spectrometry screening would show that the majority of plastic pieces (each

representing a unit) would not contain PBDEs and that certain waste streams could be

excluded from the gas chromatography mass spectrometry (GCMS) analysis. This would

have meant that a larger number of samples could be tested within selected component

waste streams to increase certainty in the range data produced. In the event the

screening showed that the majority of the data shows that that there was detectable

contamination across all target waste electrical and electronic equipment and it was

therefore necessary to spread the available GCMS testing resource across all

component streams. The range of data for each congener group is wide and the number

of samples in each category smaller than was originally intended and this hinders any

attempt to estimate the quantities of PBDEs in the overall UK waste stream with

acceptable certainty. Specifically the estimates of listed PBDE in UK waste electrical and

electronic equipment would be substantially improved if the number of samples in each

category is increased by further sampling and testing to allow the corresponding

distributions of PBDE concentrations to be estimated: i.e. confirmation of lognormality,

and summary statistics including the mean, variance and upper and lower percentiles.

Defra

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© WRc plc 2012 36

5.2 Levels of listed PBDEs in waste electrical and electronic equipment

The significant concentrations of listed PBDEs in printed circuit boards, TVs and industrial IT

equipment are such that may exceed future EU limits. This is of major significance if we

consider that the contribution of IT equipment and TVs is circa 34% of the total UK waste

electrical and electronic equipment stream and potentially poses a significant problem to

waste electrical and electronic equipment recycling in the UK. Management measures may be

needed to remove contaminated material prior to re-processing. The PBDE concentrations

detected in all the waste electrical and electronic equipment streams tested in this study

would fail to meet proposed lower limits for some PBDE bromination groups.

Of the listed PBDEs, hepta-BDE and to a lesser extent hexa-BDE appear to be the

predominant listed contaminants, particularly in TVs, IT equipment (PC monitors) and

digiboxes. Each sample of shredded waste electrical and electronic equipment tested by

GCMS is representative of at least 100 units, although the number of samples tested in

relatively small, 42 in total (and smaller within each waste stream) the data is believed to

provides a representative snap-shot of each waste stream.

The concentrations of listed PBDEs vary from < 1 - 36,500 mg/kg but are generally below

5000 mg/kg. This concentration is too low to be effective as a flame retardant and it is

believed that these plastic items have been contaminated through incorporation of plastic

recyclate containing listed PBDEs into new manufactured products. This suggests that

although dilution of listed PBDEs will occur during repeated recycling, it will take a

considerable time to eradicate these substances from the WEEE stream unless measures are

put in place to remove them prior to re-processing or the process has a suitable separation

stage. From the initial findings of this study it could be a number of decades before the UK

might expect to see PBDE free consumer goods being discarded.

5.3 Levels of PBDEs in ELV

Samples will be collected in January 2012 to address the gap in new data for ELV. Data will

be reported to Defra as a supplementary Annex to this report.

5.4 PBDE Quantification by High Resolution GCMS

A PBDE test method was developed to support this programme of work. Despite extensive

method development the determination of PBDEs in plastic and foam matrices continues to

be a challenge, although a UK laboratory is now in a position to test for target PBDEs in the

plastic from waste electrical and electronic equipment. However, the technique requires a

specialist laboratory, a multi-stage sample preparation and extraction procedure and high

resolution GCMS to test the final sample. The method is capable of determining sub

0.05 mg/kg of individual PBDE congeners in waste electrical and electronic equipment

plastics. However, the complexity, and cost of the test, means it is not a tool that is applicable

to routine process monitoring nor indeed is this method likely to be suitable for routine

regulatory testing. The analytical methodology used to undertake analysis of plastic samples

Defra

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© WRc plc 2012 37

by MSS has been optimised for the determination of PBDEs in plastic materials. Additionally

the use of labelled internal standards allows concentration of PBDEs to be determined using

internal standardisation which allows recovery correction of PBDE data. The use of internal

standards eliminates the need for correction equations (or recovery factors). This approach to

analysis is established and applied in a wide range of analytical applications. The results from

the UK laboratory were successfully correlated with test data on a selected number of

samples to a European test facility which has considerable experience of testing WEEE

matrices.

5.5 Suitability of XRFS as a screening tool

XRFS provides a rapid technique for the assessment of total bromine in ELV and WEEE. The

limitations of the test arise from the fact that it cannot distinguish between PBDEs and other

bromine containing compounds or determine which PBDEs are present in the sample i.e.

whether the PBDEs listed in the annexes of the Stockholm Convention on Persistent Organic

Pollutants are present. This aside with the exception of printed circuit boards which are known

to contain tetrabromobisphenol A, the correlation between XRFS data and GCMS indicates

that PBDEs appear to be the primary bromine containing compound in other WEEE. Many of

the samples tested provide low <100 mg/kg total bromine but this could be consistently linked

to low concentrations of listed PBDEs, Such low concentrations of PBDE have little value as

flame retardants and it is concluded that this is consistent with recycling of listed PBDEs in the

waste plastic stream into new products. Conversely where bromine concentrations exceeded

1% w/w whilst the majority of this could be attributed to non-listed PBDEs that are legitimately

being added during manufacture low levels of listed PBDEs are also present. We conclude

that XRFS can be used as a crude but effective screening tool to identify WEEE and ELV

containing bromine and potentially PBDEs. The results of this relatively limited study suggest

that a positive XRFS bromine result provides a good indicator measure for the presence of

listed POPs. In particular very low total bromine concentrations (<500 mg/kg) are often linked

specifically to listed PBDEs.

5.6 Proposals for further work

The authors suggest that the precision associated with PBDE concentrations in the

current dataset could be improved by testing additional samples. Further analysis is

recommended of the key waste streams identified as contributing significant quantities

of listed PBDEs to the UK waste stream i.e. large household appliances and ICT and

consumer electronics. This is either because they contain high listed PBDE

concentrations or they form a substantial proportion of WEEE arisings. WRc already

hold a number of additional samples of TVs, PC monitors and digiboxes in the ICT

category that have not been tested by GCMS, but further sampling would be needed to

acquire shredded large household appliances as single items were only available for

the current study. A minimum of 8, but ideally 12 samples should be tested for each of

these categories. Further testing will improve both the weighted average and reduce

uncertainty in any grossing up estimates.

Defra

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© WRc plc 2012 38

A detailed breakdown of UK waste electrical and electronic equipment arisings is

required at a finer level to allow derivation of more accurate gross estimates for PBDEs

in UK WEEE. Combining categories such as TVs and PCs, which have different list and

non-listed PBDE concentrations and congener profiles will not lead to accurate

grossing data. Further corroborated data is required for the percentages of PBDE

containing components in some WEEE categories e.g. cooling equipment. Similar data

is required for ELV.

The current study has provided valuable information on the levels of PBDEs in the UK

WEEE stream, and it is hoped that samples of ELV will be available for testing in the

January 2012.

These sub-samples provide a measure of within sample variability, which is in effect a

measure of the differences between component units. Whole samples provide a

measure of between sample variability. The high level of within sample variability

shows the importance of robust sampling procedures for these waste streams.

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References

DIRECTIVE 2002/95/EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 27 January

2003 on the restriction of the use of certain hazardous substances in electrical and electronic

equipment.

DIRECTIVE 2002/96/EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 27 January

2003 on waste electrical and electronic equipment (WEEE) Official Journal of the European Union

13.2.2003.

REGULATION (EC) No 850/2004 OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 29

April 2004 on persistent organic pollutants and amending Directive 79/117/EEC.

WRAP (2005) The Waste & Resources Action Programme, Develop a process to separate brominated

flame retardants from WEEE polymers - Interim Report 2, 20 August 2005, ISBN: 1-84405-147-1.

Stockholm Convention (2009) UNEP Stockholm Convention on Persistent Organic Pollutants (2009):

Revised draft risk profile: short-chained chlorinated paraffins. 9 November 2009.

European Commission (2010) Study on waste related issues of newly listed POPs and candidate

POPs.

WRc (2011) Sampling plan for assessment of PBDEs in WEEE streams.

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Appendix A PBDE Method Development

A1 XRFS Scanning

A1.1 Scan time

A handheld Niton XL3t 700 XRFS (X-Ray Fluoresence Spectrometer) was selected for the

determination of total bromine in the plastics samples. The unit works by placing the sample

in front of the X-Ray beam for a selected scanning period to determine the total bromine

content of the sample. The error associated with each reading is inversely proportional to the

length of time the sample is scanned. The plot in Figure A.1 shows this error decreases with

the amount of time taken to scan the sample.

Figure A.1 Plot showing error associated with XRFS reading against time taken on

scan

The plot shows the inverse exponential relationship between time and error. This indicates

that after the first minute of scanning, the benefit decreases exponentially with the period of

scanning time. It was subsequently found that 30 seconds was the optimum length of time to

scan samples for optimum balance between getting accurate measurements for single

samples, and scanning as many samples as possible.

A1.2 Sample variability

The variability within a single piece of moulded plastic was investigated. From 16 readings it

was found that variability within a single piece was very low, with a relative standard deviation

y = -2.124ln(x) + 12.689 R² = 0.9189

0

2

4

6

8

10

12

0 20 40 60 80 100 120 140

Time versus error

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of 8.4%. Much of this observed variability can be attributed to the average error on these

readings of 6.9%. It was therefore considered that the variability within a single piece of

plastic was insignificant.

A2 Method for GCMS

High resolution GCMS analysis was carried out by two laboratories, Marchwood Scientific

Services (MSS) and the Fraunhoffer Institute in Germany. The Fraunhoffer Institute were

contracted to provide confirmatory data on four samples following the development of a new

method by MSS. A mixed sub-sample of the laboratory test sample prepared by MSS was

tested by the Fraunhoffer Institute. The congener suites used by the two test laboratories

differed slightly but provided good overlap.

The methods adopted by these two laboratories are summarised in the following sections.

A2.1 Fraunhoffer Institute

Applied methods were in accordance with IEC 62321. The Fraunhoffer laboratory considered

that UK sample preparation was acceptable, both in terms of avoiding excessive heating

(which would be indicated by the smell of degraded polymers) and from the quality of the

measured PBDE fingerprints. Materials were extracted /dissolved with tetrahydrofurane and

extracts solutions were first purified by precipitation with hexane. Precipitated polymers were

re-extracted and precipitated twice with the resulting extracts combined. The combined

extract was reduced to 1 ml by vacuum rotary evaporation and then purified on a 500 mg

Silica SPE (Strata Si -1, Phenomonex). SPE was preconditioned with hexane and PBDEs

were eluted with hexane.

Cleaned extracts were again reduced to 0.5 to 1 ml by a gentle stream of nitrogen. A 10 μl

aliquot of the extract was combined with 10 μl of an internal standard mixture (BFR-LCS,

Wellington) and subjected to GCMS (Shimadzu 2010). The GCMS was operated in SIM

monitoring to fragment ions per analyte. Recovery data for the stated clean-up procedures

and matrix spiked samples met internal quality control requirements.

A2.2 Marchwood Scientific Services

The majority of analysis for PBDEs that has been undertaken worldwide is on environmental

samples, typically for water, soil, sediment and aquatic mammals. MSS has successfully

analysed a large number of this type of sample previously using established methods using

High Resolution Gas Chromatography-Mass Spectrometry. MSS undertook an intensive

period of method development to undertake the analysis of PBDEs in commercial plastic

samples. C13 labelled standards were sourced to assist in method validation.

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The first step involved defining a sample preparation protocol to produce a <1 mm particle

size fine ground laboratory sample for extraction of PBDEs. A Retsch grinder (a ZM1 ultra-

centrifugal mill) was purchased to prepare a <1 mm ground sample for testing. This

equipment avoids the production of undue heat which both melts the plastic and leads to

degradation of the PBDEs). Prepared samples were stored in dark bottles to limit

photodegradation. A 0.1 gram representative sub sample of the ground material was then

taken for analysis. The 0.1 gram portion was placed in a soxhlet thimble and inserted into a

soxhlet extraction apparatus. A toluene solvent extraction was then undertaken for

approximately 12 hours. At the end of the extraction period the solvent phase was cooled and

subjected to vacuum rotary evaporation to reduce the solvent volume to 1 ml. The sample

was then purified on a 500 mg Silica SPE column and any PBDEs present in the sample were

eluted with hexane. An aliquot of the clean extract was then analysed by High Resolution Gas

Chromatography-Mass Spectrometry (Waters Micromass). Considerable work was

undertaken to optimise the preparation, extraction and analytical methods and get acceptable

recovery of labelled C13 compounds in all stages. Final concentrations of PBDEs were

calculated based on the original weight of sample presented for extraction. The analytical

methodology used to undertake analysis of plastic samples by MSS has been optimised for

the determination of PBDEs in plastic materials. Additionally the use of labelled internal

standards allows concentration of PBDEs to be determined using internal standardisation

which allows recovery correction of PBDE data. The use of internal standards eliminates the

need for correction equations (or recovery factors). This approach to analysis is established

and applied in a wide range of analytical applications.

The method developed by MSS for the determination of PBDEs in plastics requires the

assessment of PBDE recovery from a matrix sample to provide full method validation (a

‘blank’ or low PBDE plastic reference sample could not be obtained within the timeframe of

the method development activities, but this will be addressed if further testing is required).

Criteria for acceptance of calibration samples (including a standard reference material) and

internals standard recovery have been agreed for future testing.

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Appendix B Results

B1 Samples selected for GCMS analysis and tests data

Table B.1 Samples submitted for GCMS analysis and XRFS screening data

Category Sample code No. Samples Average Br content

of the bag by XRFS

(mg/kg) Small WEEE A3 1¹ 400 Coat hangers A11 4 1000 TVs A14 4 6000 Computer monitors A26, A28, A33 7 10000 Fridges A6 2 450 Digiboxes A9 4 1200 Industrial IT equipment F1 1 20000 Mixed IT waste and

telephones F2 4 20000

Printed circuit boards S10, S19b 2 25000* Granulated plastic

output A41 1 40000

Small WEEE A3 1 400

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Table B.2 MSS GCMS PBDE test data

Component description Concentration (mg/kg)

XRFS tri tetra penta hexa hepta octa nona deca Sample code

Cloth from car headrest - 0.0032 0.025 0.031 0.058 0.35 - - 20 C16

Coat hangers <LOD 0.0025 0.029 0.056 0.14 0.72 0.073 0.11 21 A11

Coat hangers – high High 0.76 3.5 5.6 75 3400 640 290 80000 A11

Coat hangers – low Low 0.0031 0.039 0.075 1.3 7.7 0.97 2 93 A11

Coat hangers – medium Medium 0.055 0.3 0.74 2.3 7.2 - 18 2800 A11

cordless telephone - 0.0014 0.032 0.064 0.2 1 0.046 1.5 790 C11

Digiboxes (high impact plastic - HIPs) Low 0.0002 0.0029 0.0039 0.0091 0.039 - - 4.4 A8

Digiboxes (high impact plastic - HIPs) Medium 0.27 - 0.0035 0.33 2.8 - 0.27 520 A8

Digiboxes (high impact plastic - HIPs) High 2.3 220 460 1500 5000 1700 290 5700 A8

Digiboxes (high impact plastic - HIPs) - 0.0015 0.026 0.049 0.16 0.83 0.042 1.4 290 A8

Dishwasher switch cover - 0.043 0.096 0.53 2.8 3.3 1.2 180 2000 C9

dishwasher timer - 0.00095 0.036 0.08 0.28 1.5 - 5.2 910 C10

Facia washing machine - 0.0035 0.029 0.042 0.14 0.95 0.036 0.13 1300 C5

Fridges Fines 0.32 0.51 1.6 13 44 4.2 28 160 A6

Fridges >1mm 0.5 3.2 4.5 11 - 6.4 12 79 A6

Industrial IT waste High 25 250 430 1200 6000 - 620 32000 F3

Industrial IT waste Medium 0.12 3.3 6.7 15 95 48 37 12000 F3

Industrial IT waste Low 0.0029 0.0084 0.019 0.14 0.41 0.052 0.011 2.9 F3

Industrial IT waste <LOD 0.019 0.00022 0.00038 0.00097 0.0047 - 0.04 0.16 F3

Industrial IT waste - 0.44 3.1 3.6 10 55 - 960 50000 F3

Microwave door - 0.0005 0.0071 0.047 0.2 0.18 - 3.6 2500 C6

PC cover - 2.1 6.9 9.9 24 110 - - 5800 C13

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Component description Concentration (mg/kg)

XRFS tri tetra penta hexa hepta octa nona deca Sample code

PC monitors High 0.08 0.17 0.21 3.1 20 1.8 490 14000 A17

PC monitors Medium 0.021 0.56 1 2.4 14 - 26 2400 A17

PC monitors Low 0.011 0.13 0.27 0.82 4.7 0.65 0.16 6.1 A17

PC monitors - 0.031 0.41 0.85 2.6 14 2.8 16 8000 A26

Printed circuit board cover - wash machine - 0.55 3 7.4 23 72 - 180 28000 C3

Printed circuit boards High 2.4 11 15 580 5200 170 640 130000 S10

Printed circuit boards High 1.3 5.9 7 310 2800 - 270 42000 S19b

Processed dense fraction - 0.16 2.2 4.2 340 930 12 4 2400 A41

Processed plastic - 0.14 1.8 4.5 290 840 10 3.5 2600 A31

Razor - 0.0056 0.035 0.062 3.8 21 3.3 0.61 40 C12

Small WEEE - 0.37 3.3 5.1 8 41 5.4 5.5 780 A3

Transformer cover - 6.5 14 65 310 450 180 790 23000 C1

TVs - 2.3 13 16 640 5200 63 15 140000 A39.1

TVs - 1.7 6.6 8.5 310 2800 360 85 44000 A39.2

TVs Medium 3.2 5.1 16 130 440 42 280 1600 A39.3

TVs - 0.028 0.42 0.94 2.9 17 3.2 13 11000 A13

TVs - 0.28 4.1 7.6 19 110 8.6 130 98000 C4

TVs - 5.2 30 56 4800 23000 4300 720 51000 C8

TVs Low - 0.0049 0.011 0.026 0.12 - - 21 A28

TVs high 21 2100 4400 14000 36000 1900 900 53000 A28

TVs <LOD - 0.16 0.32 0.96 5.5 0.71 0.07 34 A28

Washing machine door catch - 1.8 7.1 6.6 310 3800 430 88 46000 C14

Washing machine door - 1.5 7.4 30 47 250 - - 18000 C7

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Table B.3 Detailed breakdown of MSS GCMS analysis data

Sample type Average RSD Count Mass % >10000 mg/kg Sample code

Coat hangers 1105 3.5 50 67.8 2 A11

Digiboxes 11007 2.9 50 134 20 A8

Fridges 305 4.1 20 1061 0 A1

PC monitor 9769 2.8 66 605.3 15 A33

PC monitor 15591 2.2 50 534.5 14 A17

PC monitor 608 1.4 20 1068 0 A15

PC monitor 6962 3.4 36 221.3 8.3 A33

PC monitor 7943 3.2 36 246.3 8.3 A33

Printed circuit boards 41888 0.7 30 198.7 83 S16

Printed circuit boards 47675 0.6 30 235 86 S10

Printed circuit boards 43045 0.5 30 332 90 S19b

Small WEEE 790 2.3 20 1068 0 A3

Telephones 39999 1.1 51 290.5 39 C3

TVs 16754 2.2 65 271.1 15 A14

TVs 12299 2.5 54 260.5 18 A28

TVs 10782 3.4 49 257.34 8 A39

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B2 Statistical data review (to support range estimates)

Figures B.1 and B.2 summarise the hepta-BDE GCMS results as histograms, and suggest

that the PBDE concentrations can be regarded as log-normally distributed.

Figure B.1 Histogram of hepta-BDE concentrations in all WEEE categories,

excluding TVs

Figure B.2 Histogram of hepta-BDE concentrations in sampled TVs

The concentrations of PBDEs of different groups are also highly correlated (Table B.4 and

Figure B.3) as would be expected from widespread use of a limited number of commercial

formulations.

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Table B.4 Correlation in GCMS data between hepta- and deca-BDE

log10 concentrations Tetra Penta Hexa Hepta Deca

Correlation coefficients

with hepta 0.93 0.91 0.99 - 0.80

Mean -0.21 0.05 0.86 1.54 3.21

Figure B.3 Scatter graph hepta and deca PBDE concentrations (all ‘whole’ samples

& sub-samples)

0.001

0.01

0.1

1

10

100

1000

10000

100000

0.1 1 10 100 1000 10000 1000001000000Hep

ta c

on

cen

trati

on

m

g/k

g

Deca concentration mg/kg

B3 Estimates of PBDE concentration ranges in UK WEEE

Concentration ranges have been estimated for PBDE in UK WEEE by congener group (Table

4.2) and for Stockholm listed PBDEs (Table 4.3) for UK WEEE using the results in Table B.2

and assuming that the data is log-normally distributed. For TVs the ranges are wider than the

observed minima and maxima, because of the small number of samples. The overall

estimates would be substantially improved if the number of samples in each category was

increased by further sampling and testing, ideally to make the total number of samples in

each category up to 12. This would allow the corresponding distributions of PBDE

concentrations to be estimated: i.e. confirmation of log-normality, and calculation of summary

statistics including the mean, variance and upper and lower percentiles. There is some scope

for reducing the sample numbers down to a minimum of say 8 for each component waste

stream, at the cost of greater uncertainty in the estimates. Further examination of the test data

to further determine the correlations between congener concentrations, and between the

GCMS and XRFS results could be used to gain the maximum information from sampling and

analysis at minimum cost. High correlations imply scope for analysing the samples for a small

number of parameters and estimating the values of other parameters. The range data

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illustrates that the 'within sample' variability is substantial and care must therefore be taken to

collect representative samples for testing that contain pieces from a large number of units.

Confidence limits have been estimated for the PBDE range data. The confidence limits

assume that samples have been chosen randomly. Published data for UK waste arisings

(Table 1.1) and the weight of brominated plastics in consumer items (Table 1.2) are assumed

to be correct. Estimated range data and confidence limits are provided in Table B.5.

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Table B.5 Estimated confidence limits for range estimates of PBDEs in UK waste stream

Waste category

UK waste (2010) Brominated

plastics in waste

No. of

samples Mean PBDE concentrations in samples (mg/kg) Weight in UK waste (tonnes)

Tonnes % by

weight % Tonnes Tetra Penta Hexa Hepta

All

Stockholm

listed

Best

estimate

Lower

limit

(5%ile)

Upper

limit

(95%ile)

Large household

appliances 141,236 31.0% 0.29% 410 6 2.9 7.4 63.9 688.0 762.2 0.312 0.067 0.817

Cooling appliances

containing

refridgerants 97,414 21.0% 0.29% 283 2 1.9 3.1 6.5 25.2 36.6 0.010 0.003 0.022

Small household

appliances 22,870 5.0% 0.75% 172 3 1.1 1.7 2.8 14.1 19.7 0.003 0.001 0.009

ICT & consumer

electronics 186,435 40.0% 18.00% 33,558 15 26 51 582 3002 3661 123 53 242

Lamps 0.4 0.0%

Other waste 13,265 3.0%

Total (tonnes/year) 461,220

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B4 Interlaboratory comparison of GCMS data

Direct comparison between the MSS and Fraunhofer results is possible for 5 samples (Table

B.6) and 14 PBDE congeners. To illustrate the similarities and differences between the two

sets of laboratory results, MSS concentrations reported as being less than 50 ppb (or

recorded as ‘-‘) were replaced with half the Fraunhofer limit of detection, i.e. 25 ppb. Similarly

Fraunhofer results of ‘<50’ were replaced with 25 ppb (Table B.7).

Logs to base 10 were calculated for all the results, and the differences between the log values

(MSS – Fraunhofer) were calculated. Thus a difference of 1.0 would show that the MSS result

was a factor of 10 greater than the Fraunhofer result; these are shown in bold type in Table

B.8. A zero difference occurs when the results from both laboratories were below the

detection limit; these are shown in italic type in Table B.8. A number of conclusions can be

drawn from the data:

MSS results for sample S10 High are much higher than Fraunhofer’s.

MSS results are higher than Fraunhofer’s for 3 congeners: 183, 154 and 100.

If these 3 congeners and the S10 ‘High sample’ are excluded, there is a fair measure of

agreement between the laboratories (Table B.9). As the data comparison between

other samples is acceptable, the poor correlation in data in Sample S10 high may be

explained by sample heterogeneity, XRFS showed that the individual pieces of plastic

in this sample had widely differing concentrations of PBDEs, this may impact on the

homogeneity of the sample even when it is finely ground.

Table B.6 Samples tested for interlaboratory comparison

Sample Description

A17 High TV casings

A41 Dense (high Br) fraction from reprocessor

C10 Washing machine door

C11 Circuit board casing (washing machine)

S10 High Printed circuit boards, mixed

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Table B.7 Summary of MSS and Fraunhofer PBDE results

Congener 17 28 47 66 71 85 99 100 138 153 154 183 203 209 Total tetra

- hepta tri tri tetra tetra tetra penta penta penta hexa hexa hexa hepta octa deca

Fraunhofer

A17 High 25 25 25 25 99 25 25 25 154 320 25 578 173 13,557,000 1,301

A41 25 25 1,180 25 25 25 1,532 25 275 8,045 612 69,222 9,524 746,000 80,966

C10 25 25 25 25 25 25 25 25 25 20 25 25 25 178,000 245

C11 25 25 25 25 25 25 25 25 242 25 25 88 81 1,157,000 530

S10 High 25 25 25 25 25 189 25 25 25 25 25 25 25 676,000 414

MSS

A17 High 25 69 139 25 25 25 25 184 25 418 2,588 19,013 1,815 13,921,404 22,466

A41 25 140 2,202 25 25 101 616 3,519 344 36,306 302,450 929,570 12,201 2,354,575 1,275,157

C10 25 25 25 25 25 25 25 66 25 25 235 1,496 25 911,818 1,972

C11 25 25 25 25 25 25 25 55 25 25 179 1,042 25 791,748 1,451

S10 High 1,393 1,017 9,639 1,272 318 25 1,637 13,450 25 42,101 540,261 5,231,142 172,978 129,045,077 5,839,870

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Table B.8 Comparison of MSS and Fraunhofer PBDE results

Sample

Congener Total tetra

- hepta 17 28 47 66 71 85 99 100 138 153 154 183 203 209

tri tri tetra tetra tetra penta penta penta Hexa hexa hexa hepta octa deca

A17 High 0.0 0.4 0.7 0.0 -0.6 0.0 0.0 0.9 -0.8 0.1 2.0 1.5 1.0 0.0 1.2

A41 0.0 0.7 0.3 0.0 0.0 0.6 -0.4 2.1 0.1 0.7 2.7 1.1 0.1 0.5 1.2

C10 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.4 0.0 0.1 1.0 1.8 0.0 0.7 0.9

C11 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.3 -1.0 0.0 0.9 1.1 -0.5 -0.2 0.4

S10 High 1.7 1.6 2.6 1.7 1.1 -0.9 1.8 2.7 0.0 3.2 4.3 5.3 3.8 2.3 4.1

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Table B.9 Summary of interlaboratory GCMS data comparison

Log10(M/F) <-0.5 -0.5 to +0.5 >+0.5 Total

Sample S10 High 5 37 (25) 28 70

Congeners 100, 154 & 183 4 36 (24) 16 56

4 samples * 11 congeners 4 34 (24) 6 44

Note 1: the numbers in brackets in the middle column show the sample – congener combinations for

which both laboratories’ results were below the detection limit

Note 2: log10(M/F) is the log to base 10 of the MSS to Fraunhofer ratio. A value of 0.5 corresponds

roughly to a factor of 3 difference.