Brominated Flame Retardants

Substance Flow Analysis and Assessment of Alternatives

Contents

Preface

Summary

Dansk sammendrag


1 Introduction to Brominated Flame Retardants
1.1 Flame retardants
1.2 The Chemistry of Brominated Flame Retardants
1.2.1 Polybrominated Diphenyl Ethers
1.2.2 Polybrominated Bipenyls
1.2.3 Tetrabromobisphenol A and Derivatives
1.2.4 Hexabromocyclododecane
1.2.5 Other Brominated Flame Retardants
1.3 European and Global Consumption of flame Retardants
1.4 Emission from Products in Service

2 Uses in Denmark
2.1 Chemicals and Semi-manufactures
2.1.1 Import, Export and Production as Chemicals
2.1.2 Consumption with Plastic Compounds and Masterbatches
2.1.3 Consumption with Plastic Semi-manufactures
2.1.4 Consumption with Electronic Semi-manufactures
2.1.5 Emission from Production Processes in Denmark
2.1.6 Summary
2.2 Use in Manufactured Goods
2.2.1 Printed Circuit Boards
2.2.2 Housing of Electric and Electronic Equipment
2.2.3 Other Components of Electric and Electronic Appliances and Machines
2.2.4 Lighting
2.2.5 Wiring and Power Distribution
2.2.6 Textiles
2.2.7 Building Materials
2.2.8 Paints and Fillers
2.2.9 Transportation
2.2.10 Other Uses
2.2.11 Summary
2.3 Unintended Uses as Contaminant

3 Turnover with Waste Products
3.1 Recycling of Brominated Flame Retardants
3.1.1 Waste of Electric and Electronic Equipment
3.1.2 Other Recycling Processes
3.1.3 Export of Scrap
3.1.4 Limitations on Recycling of Plastics
3.2 Disposal with Solid Waste
3.2.1 Sources of Brominated Flame Retardants to Solid Waste
3.2.2 Fate of Brominated Flame Retardants by Incineration
3.2.3 Landfilling Activities
3.3 Turnover with Chemical Waste
3.4 Turnover with Waste Water
3.5 Summary

4 Summary and Discussion of the Substance Flow Analysis
4.1 Consumption in Denmark
4.2 Emission and Disposal to the Environment and Landfills
4.3 Substance Flow Balance for Brominated Flame Retardants

5 Regulations and Risk Reduction Measures with Respect to Brominated Flame Retardants

5.1 OECD initiatives
5.2 EU Initiatives
5.2.1 Legislation
5.2.2 Hazard/Risk Assessment
5.3 National Regulations
5.4 Ecolabels

6 Fire Safety Standards in Denmark, Germany and UK
6.1 Introduction
6.2 Denmark
6.2.1 Electronic Products
6.2.2 Electrical Appliances
6.2.3 Lighting
6.2.4 Wiring
6.2.5 Textiles and Carpets
6.2.6 Building Insulation Materials
6.2.7 Other Building materials
6.2.8 Transportation
6.3 Germany
6.4 UK
6.5 Summary

7 Materials and Products with Alternative Flame Retardants
7.1 General Aspects
7.2 Electronic and Electrical Appliances
7.2.1 Printed Circuit Boards
7.2.2 Electronic Component Encapsulates
7.2.3 Housing of Electronic and Electric Appliances
7.2.4 Switches, Sockets, etc.
7.2.5 Other EE Equipment Parts
7.3 Lighting
7.4 Wiring
7.4.1 Wires and Cables
7.4.2 Wall Sockets and Mounting Boxes
7.4.3 Relays, Contactors, Starters, etc.
7.5 Textiles
7.5.1 Furniture
7.5.2 Carpets
7.5.3 Clothing
7.6 Building Materials
7.6.1 Expanded Polystyrene and Extruded Polystyrene Foam
7.6.2 Rigid Polyurethanes
7.6.3 Foils
7.7 Paint
7.8 Transportation
7.9 New Flame Retardant Concepts

8 Alternative Flame Retardants
8.1 Organophosphorus
8.1.1 Triphenyl Phosphate
8.1.2 Tricresyl Phosphate
8.1.3 Resorcinol bis(diphenylphosphate)
8.1.4 Phosphonic acid, (2-((hydroxymethyl)carbamyl)ethyl)-, dimethyl ester
8.1.5 Phosphorus and Nitrogen Containing Thermosets
8.2 Inorganic
8.2.1 Aluminium Trihydroxide
8.2.2 Magnesium Hydroxide
8.2.3 Ammonium Polyphosphate
8.2.4 Red Phosphorus
8.2.5 Zinc Borate
8.3 Nitrogen Containing
8.3.1 Melamine

9 Summary of Alternatives

Literature

A. Appendix 1: List of Fire Safety Standards in Denmark, Germany and UK
B. Appendix 2: Abbreviations Used in the Report
C. Appendix 3: Physical-chemical Properties of Brominated Flame Retardants
D. Appendix 4: Brominated Flame Retardants Registered in the Danish Product Register
E. Appendix 5: List of Companies Contacted
F. Appendix 6: Calculation of brominated flame retardants in housing of electronics and printed circuit boards
G. Appendix 7: Import, Export and Production of Brominated Flame Retardants and other Bromine Compounds 1993-1997

Preface

The purpose of this project has been to analyse the flow of brominated flame retardants (BFRs) through the Danish society and identify sources of releases of these compounds to the environment and waste. In the second part of the project an assessment of the possibility of substituting other flame retardants for brominated flame retardants for specific applications have been carried out.

Background   

Brominated flame retardants are used for fire precautions with the purpose of protecting human life, health and property. The compounds have some technical advantages in many types of plastic and a relatively low human toxicity.

During the last decades, the consumption of brominated flame retardants has globally grown dramatically due to the growth in the use of synthetic polymers and the introduction of more rigorous fire safety requirements.

As a consequence of the chemical stability of the compounds, the brominated flame retardants, however, have a tendency to accumulate and spread in the environment. This accumulation in combination with some environmental adverse effects of the compounds has during the last decade placed the brominated flame retardants in the international focus.

During the last few years new results showing that brominated flame retardants are emitted from products in use and are present in the human body and breast milk in measurable quantities have further increased the focus on the compounds (e.g. /1,2/).

Esbjerg Declaration    

In the ministerial declaration of the fourth North Sea Conference in 1993, the ministers agreed to take concerted action within the framework of the competent international forums to substitute the use of brominated flame retardants, among other hazardous substances, by less hazardous or preferably non-hazardous substances where these alternatives are available.

List of Undesirable Substances

As a consequence of the ministerial declaration of the fourth North Sea Conference, brominated flame retardants have been placed on the List of Undesirable Substances, prepared by the Danish Ministry of the Environment.

International work on flame retardants is carried out in several forums.

EU 

The European Union has prohibited the use of polybrominated biphenyls in textiles.

Under the Regulation on Existing substances, EEC/793/93, France and The UK have jointly assigned decabromodiphenyl ether (DeBDE) and octabromodiphenyl ether (OcBDE), The UK have additionally assigned pentabromodiphenyl ether (PeBDE) and Sweden have assigned HBCD for risk assessment. The draft versions of the three risk assessments of the brominated diphenyl ethers have been available for the preparation of the present analysis /3,4,5/. The first draft version of the HBCD risk assessment was finished by March 1999 and has not been available for this study.

IPCS

Under IPCS, the International Programme on Chemical Safety, Environmental Health Criteria monographs have been prepared for polybrominated biphenyls (1994) /6/, brominated diphenyl ethers (1994) /7/, and tetrabromobisphenol A and derivatives (1995) /8/. Additionally a general introduction to flame retardants has been prepared in 1997 /9/. In the monographs it is recommended that polybrominated biphenyls and pentabromodiphenyl ether should not be used commercially.

One of the main concerns regarding brominated flame retardants is the transformation of the flame retardants into polybrominated di-benzop-dioxins and dibenzofurans. An Environmental Health Criteria monograph for these compounds has recently been prepared /10/. In the monograph it is recommended that brominated flame retardants should not be used where suitable replacements are available, and future efforts should encourage the development of further substitutes.

OECD

Under the OECD risk reduction programme a risk reduction monograph on selected brominated flame retardants has been prepared /11/. Following the publication of the monograph, OECD engaged in discussions with the manufacturers of the brominated flame retardants. US and European industry have developed a Voluntary Industry Commitment on actions they will undertake to further manage risks posed by the manufacture, import and export of these flame retardants. Joint meetings between OECD and the industry oversee industry's implementation of the commitments.

National initiatives

A number of national activities concerning BFRs have been initiated. The present report includes a survey of national activities with respect to regulation, soft regulation, risk and hazard assessment activities and national positions on the issue of brominated flame retardants.

Method

The substance flow analysis is performed in accordance with the Danish Environmental Agency's paradigm for substance flow analyses /12/. The analysis of the consumption of BFRs with manufactured products is carried out at a screening level. At present no Danish analyses of BFRs in waste water, sludge, flue gas or residues from solid waste incineration exist. As a consequence the turnover of BFRs with waste products has been estimated from scenarios based on the most probable assumptions.

All values are represented by intervals. The intervals represent the range within which the authors estimate that the right value will be with a probability of 80%.

Abbreviations

Abbreviations of plastics and chemical compounds used in the report are explained in appendix 2.   

Steering committee

The project has been followed by a steering committee with the following members:

Elisabeth Paludan (chair), Danish Environmental Protection Agency
Henrik Søren Larsen, Danish Environmental Protection Agency
Tonny Christensen,Danish Environmental Protection Agency
Ivan Grønning, Danish Toxicology Centre
Pernille Thomsen, Danish Plastic Federation
Jan Hohberg, Elektro-Miljø A/S
Niels Bay Alexandersen, Bang & Olufsen A/S
Lina Ivar Andersen, Danish Institute of Fire Technology
Carsten Lassen, COWI Consulting Engineers and Planners
Nanna P. Brandorff, National Working Environment Authority   

Authors   

The report has been prepared by Carsten Lassen and Søren Løkke, COWI Consulting Engineers and Planners, and Lina Ivar Andersen, Danish Institute of Fire Technology. The quality assessment has been carried out by Erik Hansen, COWI Consulting Engineers and Planners.

Summary

The consumption of brominated flame retardants (BFRs) with end products in Denmark in 1997 is estimated at 320-660 tonnes. Tetrabromobisphenol A (TBBPA) and derivatives accounted for about half of the consumption, and the consumption of these flame retardants is increasing. The more controversial compounds, polybrominated biphenyls (PBBs) and polybrominated diphenyl ethers (PBDEs) accounted for approximately 1% and 9%, respectively, of the consumption with end products. A marked shift away from PBDEs has taken place in Danish production and for a part of the imported products. The knowledge on the emissions of the brominated flame retardants to the environment is still very limited. Model estimates indicate that the major source of brominated flame retardants lost to the environment is evaporation from products in use. No recycling activities are taking place for materials containing brominated flame retardants. Broadly all electronic equipment, as well as a major part of other electrical devices, contains brominated flame retardants. For two large application areas - TV sets and computer monitors - the trend of the recent years has been a shift away from the use of brominated flame retardants. This is partly due to the influence of ecolabels. Today, alternative flame retardants are available for applications that quantitatively account for the major part of the consumption of brominated flame retardants. The current knowledge of the environmental properties of the substitutes is limited, however. For a number of applications that account for a major part of the BFRs used for Danish production, substitutes are still at the developmental stage.

Background and Objectives

The term 'brominated flame retardants' cover a large number of different organic substances, all with bromine in their molecular structure. Bromine has an inhibitory effect on the formation of fire in organic materials. Flame retardants are added to plastics and textiles in order to comply with fire safety requirements.

The most widely used substances - among these TBBPA, PBDEs and PBBs - contain one or more carbon rings, making them very stable and efficient in a large number of plastics.

The chemical stability of the substances - particularly in the cases of PBBs and PBDEs - is also the reason why brominated flame retardants for years have been in focus in the international environmental debate. PBDEs and PBBs, which are the most stable of the described BFRs, are spread widely in the environment, are bioaccumulated and are accumulated in sediments, where they are only very slowly degraded.

With the aim of reducing the release of brominated flame retardants to the marine environment, Denmark has committed itself in the Esbjerg Declaration of 1993, to promote the substitution of brominated flame retardants with less problematic substances if such are available.

Recent research has revealed that some of the brominated flame retardants are emitted to the indoor environment from the products in use. Increasing concentrations of PBDEs have been observed in human breast milk.

Risk assessments on three PBDEs and HBCD have been carried out within the EU since the mid nineties. The results of the assessments of the PBDEs are expected to be presented in 1999.

No previous assessments of brominated flame retardants have been carried out in Denmark. It is the aim of this study to establish an overview of the use of these substances in products manufactured in, and imported to, Denmark. In addition the purpose of the project is to assess the possibilities of and limitation for substitution of brominated flame retardants.

Studies in other countries have shown that the use of flame retardants has an important role in saving lives. This issue and more broadly the social advantages of the use of flame retardants has not been covered by the present study.

The Study

This study has been carried out in accordance with the paradigm for substance flow analysis of the Danish Environmental Protection Agency. The knowledge presented is based on data from Statistics Denmark, the Danish Product Register, the literature, market analyses, public institutions as well as from private organisations and companies. In the analysis, all the information has been hold together to describe the total flow of brominated flame retardants through the Danish society.

Data on the import of brominated flame retardants with polymer raw materials for production in Denmark has been obtained through a questionnaire in co-operation with the Danish Plastic Federation.

An attempt has been made to collect information on the contents of brominated flame retardants in imported goods via trade companies and importers. This has proven difficult, as most vendors do not know, whether the products in question contain brominated flame retardants. As a consequence, the analysis for a number of product types has been based on data on the European market for flame retardants and flame retarded polymers. Based on such information, it has been possible to determine which flame retardants are likely to be used in the different types of end products.

No measurements of the concentrations of brominated flame retardants in Danish waste water and sewage sludge have been found. Similarly no measurements of emissions from production or products in use are available. No Danish studies have been made on the fate of brominated flame retardants in the waste treatment systems. Hence, it has been necessary to estimate the potential loss of brominated flame retardants to the environment considering the few available foreign analyses and model estimates. The presented estimates of losses to the environment are therefore to be considered as the author's best estimate based on the existing knowledge.

Information on alternative flame retardants, and products containing alternatives, has been obtained from suppliers of flame retardants and plastic raw materials, as well as searches on the Internet and direct contact to producers using alternatives. Brominated flame retardants account only for about 15% of the Western European market for flame retardants. For many purposes, for instance carpets and PVC, other types of flame retardants are generally used. For this reason, only the applications where brominated flame retardants are used today, have been included in the assessment of alternatives.

In order to give a first overview, potential risks related to alternative flame retardants were identified on the basis of existing reviews.

This study has been carried out in 1998/99, and the data represent the 1997-situation.

The main conclusions of the project are:

The results

The present study consists of two parts: a substance flow analysis of brominated flame retardants and an assessment of alternatives to brominated flame retardants.

Extended summary of the results and discussion of the substance flow analysis can be found in chapter 4.

The aim of the assessment of alternatives is to identify possibilities of and limitation for substitution of brominated flame retardants. Extended summary for the assessment of alternatives can be found in chapter 9.

Dansk sammendrag

Bromerede flammehæmmere - massestrømsanalyse og vurdering af alternativer

Forbruget af bromerede flammehæmmere med færdigvarer i Danmark var i 1997 på 320-660 tons. Tetrabrombisphenol A (TBBPA) og derivater deraf tegnede sig for omkring halvdelen af forbruget, og forbruget af disse stoffer er stigende. De mest kontroversielle stofgrupper, polybromerede diphenyler (PBB) og polybromerede diphenylethere (PBDE), tegnede sig for henholdsvis ca. 1% og ca. 12% af forbruget med færdigvarer. Der er sket et markant skift væk fra PBDE i dansk produktion og i dele af de importerede varer. Der findes kun en meget begrænset viden om, hvorledes stofferne spredes til miljøet. Modelberegninger tyder på, at den væsentligste kilde til spredning af bromerede flammehæmmere i miljøet er fordampning fra de produkter, hvori de indgår. Der sker ingen genanvendelse af materialer indeholdende bromerede flammehæmmere. Stort set alle elektroniske apparater og en stor del af andre elektriske produkter indeholder bromerede flammehæmmere. Der er i de senere år sket en udvikling væk fra bromerede flammehæmmere indenfor et par af de store anvendelsesområder - computerskærme og TV apparater - hvor bl.a. mærkningsordninger har været med til at præge udviklingen. Der findes i dag alternativer til bromerede flammehæmmere til anvendelser, der dækker hovedmængden af forbruget, men der er en begrænset viden om flere af alternativernes miljømæssige egenskaber. Til en række anvendelser - som tegner sig for en stor del af forbruget til produktion i Danmark - er alternativer stadig på forsøgsstadiet.

Baggrund og formål

Betegnelsen "bromerede flammehæmmere" omfatter en lang række forskellige organiske stoffer, som har det til fælles, at de indeholder brom, der virker hæmmende på udviklingen af brand. Brandhæmmere tilsættes plastmaterialer og tekstiler, for at disse kan opfylde de opstillede krav til brandsikkerhed.

De mest anvendte af stofferne - heriblandt TBBPA og stofgrupperne PBDE og PBB - indeholder én eller flere organiske ringstrukturer, som gør stofferne meget stabile og effektive i en lang række af plastmaterialer.

Stoffernes stabilitet - især stabiliteten af PBB og PBDE - er dog også årsag til at de bromerede flammehæmmere i en årrække har været i fokus i den internationale debat. PBDE og PBB, som er de bedst beskrevne af stofferne, spredes langt omkring i miljøet, opkoncentreres i fødekæderne og ophobes i sedimenter, hvor de kun nedbrydes langsomt.

Med den hensigt at mindske spredningen af bromerede flammehæmmere i havmiljøet, har Danmark i Esbjerg Deklarationen fra 1993 forpligtet sig til at arbejde for at bromerede flammehæmmere erstattes med mindre problematiske stoffer, i det omfang sådanne findes.

I de senere år er der kommet udenlandske resultater frem, der viser, at stofferne afgives direkte fra produkter i indemiljøet. Der er ligeledes påvist stigende koncentrationer af stofferne i modermælk.

I EU har der siden midten af 1990'erne været arbejdet med risikovurderinger af tre stoffer inden for stofgruppen PBDE samt stoffet HBCD. Resultaterne af vurderingerne af PBDE forbindelserne forventes at ligge færdige i løbet af 1999.

I Danmark er der ikke tidligere lavet undersøgelser vedrørende bromerede flammehæmmere. Det er hensigten med dette projekt, at få et overblik over, i hvilket omfang disse stoffer anvendes i produktionen i Danmark og indgår i såvel dansk producerede som importerede færdigvarer. Desuden har projektet til formål at undersøge mulighederne og begrænsningerne for udskiftning af bromerede flammehæmmere med alternativer.

Udenlandske undersøgelser viser at brugen af flammehæmmere er med til at spare menneskeliv. Dette aspekt og mere bredt - den samfundsmæssige nytte af brugen af flammehæmmere - er ikke dækket af dette projekt.

Undersøgelsen

Projektet er gennemført i overensstemmelse med Miljøstyrelsens retningslinier for massestrømsanalyser. Den viden, som fremlægges i rapporten, er baseret på oplysninger fra Danmarks Statistik, Produktregistret, litteraturen, offentlige institutioner samt private organisationer og virksomheder. I analysen sammenholdes alle oplysninger til et samlet billede af massestrømmen af bromerede flammehæmmere gennem det danske samfund.

Oplysninger om import af bromerede flammehæmmere med plastråvarer til produktion i Danmark er indhentet gennem en spørgeskemaundersøgelse, som er gennemført i samarbejde med Plastindustrien i Danmark.

Oplysninger om indholdet af flammehæmmere i importerede varer er forsøgt indhentet via forhandlere og importører. Det har været vanskeligt at opnå konkrete informationer, fordi forhandlere oftest ikke ved om produkterne indeholder bromerede flammehæmmere. For en række produkttyper er der i analysen derfor taget udgangspunkt i oplysninger om det europæiske marked for flammehæmmere og flammehæmmet plast. På dette grundlag er det vurderet, hvilke flammehæmmere der vil kunne forventes at være i de forskellige produkter.

Der findes ingen danske målinger af bromerede flammehæmmere i spildevand og slam fra renseanlæg, eller af emissioner fra produktionsprocesser og produkter i brug. Der findes heller ingen danske undersøgelser af flammehæmmernes skæbne i forbindelse med affaldsbehandling. Det har derfor været nødvendig, at tage udgangspunkt i de få udenlandske målinger der findes, og bruge beregningsmodeller til at vurdere de mulige tab af bromerede flammehæmmere til omgivelserne. De angivne tab til omgivelserne er derfor udtryk for, hvad forfatterne vurderer som mest sandsynligt ud fra den eksisterende viden.

Oplysninger om alternative flammehæmmere og produkter hvori disse bruges er indhentet fra leverandører af flammehæmmere og plastråvarer, via internetsøgninger samt gennem direkte kontakt til virksomheder, der benytter alternativer. Bromerede flammehæmmere udgør i Vesteuropa kun ca. 15% af markedet for flammehæmmere. Til mange formål, fx. flammehæmning af tæpper og PVC, anvendes der sædvanligvis andre typer af flammehæmmere. I opgørelsen af alternativer er der derfor kun medtaget anvendelser, hvor bromerede flammehæmmere bliver anvendt i dag.

For at give et første overblik, er der på baggrund af eksisterende sammenfatninger peget på mulige risici i relation til en række alternative flammehæmmere.

Undersøgelsen er gennemført i 1998/99, og det anvendte datamateriale vedrører 1997-forhold.

Hovedkonklusioner:

Projektresultaterne

Generelt om bromerede flammehæmmere

"Bromerede flammehæmmere" omfatter en lang række organiske forbindelser, som har meget forskellige tekniske og miljømæssige egenskaber. De skal ikke forveksles med de stoffer, som anvendes til slukning af brand. Der findes omkring 40 kommercielt tilgængelige forbindelser, hvoraf mindst 13 i 1997 blev anvendt i produktionsprocesser i Danmark. Bromerede flammehæmmere kan enten anvendes additivt, hvor flammehæmmeren optræder i polymeren på samme måde som en blødgører, eller reaktivt, hvor flammehæmmeren indbygges i selve polymerstrukturen og dermed ikke længere er til stede som den oprindelige kemiske forbindelse. Hovedparten af TBBPA, polyetherpolyol og andre flammehæmmere, der anvendes i hærdeplast, anvendes reaktivt. For overskuelighedens skyld angives flammehæmmeren dog stadig som den anvendte forbindelse, fx TBBPA, med den mængde der er anvendt ved produktion af plastmaterialet.

Forbruget af bromerede flammehæmmere er stigende - både i Europa og den øvrige verden. På nogle få områder, som har været i søgelyset, har der været en tendens til at udskifte de bromerede flammehæmmere med andre forbindelser, men denne tendens er blevet modvirket af en stigende efterspørgsel som konsekvens af det stigende forbrug af især elektroniske produkter og skærpede brandtekniske krav på en række områder.

Forbrug af bromerede flammehæmmere til produktion i Danmark

Bromerede flammehæmmere produceres ikke i Danmark, men importeres som kemikalier, med plastråvarer eller plasthalvfabrikata til produktion af færdigvarer i Danmark. Den samlede import i 1997 fremgår af tabel 1. Kemikalierne blev hovedsageligt anvendt til produktion af plastråvarer som reeksporteredes. Med plastråvarerne, compounds og masterbatches, importeredes der i alt 130-190 tons. De væsentligste anvendelser var TBBPA til produktion af elektriske komponenter i tekniske termoplastmaterialer og HBCD og bromeret polyetherpolyol til produktion af isoleringsmaterialer af polystyren og polyurethan. Udover import med råvarer var der en væsentlig import af TBBPA med laminater til printplader.

Hvis man sammenligner fordelingen mellem de forskellige typer af flammehæmmere anvendt til produktionsprocesser i Danmark med fordelingen på det europæiske marked er der markante forskelle. PBDE udgjorde i 1996 omkring 26% og i 1998 ca. 11% af de bromerede flammehæmmere solgt på det europæiske marked. Til sammenligning udgjorde PBDE i 1997 mindre end 1% af forbruget til produktion i Danmark. En væsentlig årsag til denne forskel er udviklingen i Tyskland, hvor råvareproducenterne ved en frivillig aftale har erstattet PBDE og PBB med andre bromerede flammehæmmere.

Tabel 1
Import af bromerede flammehæmmere med kemikalier, plastråvarer og plasthalvfabrikata til Danmark i 1997

Forbrug af bromerede flammehæmmere med færdigvarer

Det samlede forbrug af bromerede flammehæmmere med færdigvarer fremgår af tabel 2. Til mange formål kan der anvendes flere forskellige forbindelser, og det har været vanskeligt at få detaljerede oplysninger om indholdet i de fleste importerede produkter. Der er derfor benyttet en opgørelsesform, hvor der er åbnet mulighed for, at enten den ene eller den anden forbindelse er benyttet.

På et af de væsentligste områder, kabinetter til elektronik, er der sket et skift fra PBDE til TBBPA, andre bromerede flammehæmmere eller halogen-frie alternativer. Til produktion af færdigvarer er PBDE i Danmark, Tyskland og Holland i høj grad er erstattet af TBBPA eller andre flammehæmmere, men markedsanalyser tyder på, at dette ikke er tilfældet i det øvrige Europa.

Det største anvendelsesområde er elektriske og elektroniske produkter, der samlet tegner sig for ca. 70% af forbruget. Printkort med tilhørende elektronik komponenter tegner sig alene for ca. 29% af det samlede forbrug. Der anvendes næsten udelukkende TBBPA til printkort og indstøbning af elektroniske komponenter. Kabinetter - især til kontormaskiner - tegner sig for andre 21% af forbruget. For TV-kabinetter er der sket en markant udvikling væk fra brug af bromerede flammehæmmere, som stort set ikke længere findes i TV-kabinetter på det danske marked. Kontakter, stik, ledninger, indstøbningsmasser, motordele og i det hele taget mindre dele, som er i kontakt med strømførende dele i elektriske apparater og maskiner, udgør omkring 7% af det samlede forbrug. Da der er tale om mange små dele, som indgår i meget stort antal produkter, er den samlede mængde beregnet ud fra overordnede opgørelser af brugen af flammehæmmet plast til denne type produkter. Inden for dette anvendelsesområde er der et væsentligt forbrug med tekniske termoplasttyper som PBT og PET, som anvendes til stik, kontakter mm. Til disse plasttyper anvendes stort set kun bromerede flammehæmmere.

Denne anvendelse udgør også en væsentlig del af forbruget med dele til elektriske installationer i bygninger og industri samt i forsyningsnettet, der samlet repræsenterer omkring 11% af det samlede forbrug. Ud over kontakter, relæer, startere osv. er der et væsentligt forbrug af bromerede flammehæmmere med gummikabler.

Isoleringsmaterialer af ekspanderet polystyren og opskummet polyurethan tegner sig for hovedparten af de 15% af det totale forbrug, som byggematerialerne udgør. Polystyrenen anvendes i byggeriet fx. til isolering af kældre, mens polyurethan især anvendes til isolering af køle/frysehuse. Det er kun en mindre del af den ekspanderede polystyren, der anvendes i byggeriet, der indeholder flammehæmmere. I Danmark er der ikke brandtekniske krav til ekspanderet polystyren, som kun må anvendes inddækket i ikke-brandbare materialer. Årsagen til at bromerede flammehæmmere indgår i nogle af produkterne, er at de importeres fra lande, hvor ekspanderet polystyren er godkendt til bygningsisolering, hvis det opfylder visse brandkrav.

Forbrug af bromerede flammehæmmere med tekstiler og møbler er vurderet at udgøre ca. 1,3% af det samlede forbrug. I visse lande i Europa, især Storbritannien, er der et stort forbrug af bromerede flammehæmmere med tekstiler og møbler. Flammehæmmede møbler anvendes i Danmark i lufthavne, hoteller, visse kontorer og andre steder, hvor der færdes mange mennesker. Bromerede flammehæmmere anvendes generelt ikke i dansk produktion af møbler, men kan forekomme i importerede produkter. Forbruget til disse formål er groft skønnet, da det har været vanskeligt at få konkrete oplysninger om importerede produkter.

Maling og fugemidler udgjorde et beskedent bidrag på 0,2% af det samlede forbrug. Brandhæmmende maling, som anvendes i Danmark, er sædvanligvis baseret på andre typer af flammehæmmere.

Transportmidler udgjorde ca. 12% af det samlede forbrug. Biler og busser vurderes i kraft af det store antal at stå for den væsentligste del af forbruget Det samlede forbrug er dog opgjort med stor usikkerhed. Traditionelt har biler og busser indeholdt væsentlige mængder bromerede flammehæmmere, men der har i de seneste år hos europæiske producenter været en tendens væk fra brugen af disse flammehæmmere.

Epoxybaserede printkort og hård polyurethanskum tegner sig for den væsentligste del af forbruget af reaktive bromerede flammehæmmere. De reaktive anvendelser udgør i størrelsen 44% af det samlede forbrug.

Tabel 2
Forbrug af bromerede flammehæmmere med færdigvarer i Danmark, 1997.

Forbrug som følgestof

Der er ikke fundet nogen naturlig forekomst af bromerede flammehæmmere, men i naturen findes forbindelser, der i struktur minder om de bromerede flammehæmmere. Den største kilde til bromerede flammehæmmere i fødevarer i de nordiske lande er i en tidligere undersøgelse vurderet at være fisk. Den samlede omsætning med fødevarer i Danmark kan anslås til mindre end 1 kg pr. år. Der vurderes ikke at være nogen omsætning af bromerede flammehæmmere med genanvendte materialer.

Massebalance for bromerede flammehæmmere

Der findes ingen danske målinger af bromerede flammehæmmere i spildevand eller slam fra renseanlæg, udledninger fra industrier eller tab fra produkter. Der findes heller ingen danske undersøgelser, der belyser stoffernes skæbne ved affaldsforbrænding og anden form for affaldsbortskaffelse. Det har derfor været nødvendigt at tage udgangspunkt i de få udenlandske målinger, der findes, i kombination med teoretiske modeller for emission af stofferne fra produktionsprocesser og materialer. De angivne udledninger skal betragtes som et scenarie på grundlag af antagelser om de mest sandsynlige emissionsfaktorer.

På dette grundlag er der i figur 1 opstillet en massebalance for bromerede flammehæmmere i Danmark.

Figur 1
Massebalance for bromerede flammehæmmere i Danmark, 1997. Alle udledninger er anslåede på grundlag af modelberegninger.

Tab til miljøet

Bromerede flammehæmmere, der anvendes som additiv, vil kunne fordampe fra de materialer, hvori de anvendes.

Modelberegninger udviklet i tilknytning til risikovurderingerne, der for øjeblikket gennemføres i EU regi, indikerer, at op til 0,4% af deca-BDE, og op til 4% af den lettere penta-BDE kan fordampe fra materialerne over en periode på 10 år. Anvendes samme beregningsmodel for andre flammehæmmere anvendt som additiv vil der for nogle forbindelser beregnes højere afgivelsesrater. Der foreligger ikke grundige målinger, der kan be- eller afkræfte disse modelberegninger, som må betragtes som "worst case" estimater. PBDE forbindelserne er meget stabile, og er de først emitteret til luft, vil de kunne spredes over store afstande, og vil blive afsat til jord og vandmiljøet. TBBPA synes ikke at være nær så stabil i atmosfæren. Flammehæmmere anvendt reaktivt kan emitteres i det omfang, at der er sket en ufuldstændig reaktion. Den samlede mængde der frigives fra ufuldstændigt reagerede forbindelser, vurderes i det samlede billede at være ubetydelig.

De emitterede forbindelser vil hurtigt hæfte sig til partikler i luften. Partiklerne vil blandt andet sætte sig på indersiden af apparater, hvorfra de kan spredes i forbindelse med demontering af apparaterne.

Hvis modelberegningerne afspejler de faktiske forhold, må langt den væsentligste kilde til spredning af disse forbindelser til miljøet være fordampning fra produkter.

Spildevand

Der foreligger kun nogle få målinger af bromerede flammehæmmere i spildevandsslam fra Sverige og Tyskland. Målingerne tyder på, at koncentrationerne af de enkelte forbindelser er i størrelsen <100 mg/ kg tørstof.

De eneste anvendelser af bromerede flammehæmmere, hvor der i væsentlig grad er en direkte kontakt mellem det flammehæmmede materiale og vand, er tekstiler og tagbeklædninger. Tekstilvask vurderes at være en væsentlig kilde til bromerede flammehæmmere i spildevand, men udledninger er et resultat af et tidligere forbrug, da bromerede flammehæmmere tilsyneladende ikke længere anvendes i beklædninger, som sælges i Danmark. I andre lande, især Storbritannien, hvor tekstiler med bromerede flammehæmmere anvendes i stort omfang, vil tekstilvask være en langt væsentligere kilde til spredning af bromerede flammehæmmere til omgivelserne.

På grundlag af de fysisk/kemiske egenskaber af stofferne må det formodes, at flammehæmmerne i spildevand hovedsageligt vil ende op i slammet.

De samlede udledninger fra renseanlæg i 1997 vurderes at være i størrelsen 5-53 kg, mens i størrelsen 31-330 kg med slam blev udbragt på landbrugsjord.

Forbrænding og affaldsdeponering

Alle produkter indeholdende bromerede flammehæmmere vil i den sidste ende blive bortskaffet til affaldsforbrændingsanlæg eller deponeret på lossepladser.

I forbindelse med affaldsforbrændingen vil forbindelserne lang overvejende blive destrueret, men der er mulighed for, at en lille del vil kunne passere forbrændingskammeret og ende i restprodukter. Der er ingen målinger af bromerede flammehæmmere i røggas og restprodukter, og mængderne angivet i figur 1 er groft anslåede ud fra erfaringer med andre stoffer.

PBDE og PBB har i struktur meget lighed med de langt giftigere furaner og dioxiner, og under visse forbrændingsforhold kan flammehæmmerne virke som udgangsmateriale for dannelsen af furaner og dioxiner. Det er derfor af betydning at det flammehæmmede materiale afbrændes under optimale forbrændingsforhold.

Bromerede flammehæmmere, der med produkter ender på losseplads vil på længere sigt kunne afgives fra produkterne. I hvilken grad forbindelserne vil nedbrydes i forbindelse med afgivelsen eller vil kunne spredes til luft eller vandmiljøet vides ikke.

Genanvendelse af bromerede flammehæmmere

Der sker ingen genanvendelse af materialer indeholdende bromerede flammehæmmere. Genanvendelse begrænses af det forhold, at der til det samme formål anvendes mange forskellige plastmaterialer, med forskellige tilsætningsstoffer, og at det derfor er meget vanskeligt at opnå et veldefineret produkt til genanvendelse. Plast fra elektriske og elektroniske produkter, der indeholder bromerede flammehæmmere, må i følge den nye bekendtgørelse om affald af elektriske og elektroniske produkter kun anvendes til formål, hvor der er krav om anvendelse af flammehæmmet kvalitet.

International regulering

I Danmark og andre EU lande er anvendelsen af tris(2,3dibromo propyl)fosfat (TRIS) forbudt, mens polybromerede biphenyler (PBB) er forbudt til brug i tekstiler, der kommer i direkte kontakt med huden. To lande, Østrig og Schweiz, har helt forbudt brugen af PBB. I Tyskland og Holland er der indgået frivillige aftaler omkring en udfasning af PBB og PBDE, mens Kemikalieinspektionen i Sverige har indstillet til den svenske regering at de to stofgrupper totalt udfases. I Tykland har krav om, at indholdet af en række dioxiner og furaner i produkter ikke må overskride visse værdier, i praksis virket begrænsende på brugen af PBDE og PBB.

Det nordiske Svanemærke og den tyske Blå Engel har begge krav vedrørende bromerede flammehæmmere til større plastdele i en række elektroniske produkter. Kravene vedrører enten den samlede stofgruppe, eller som det er mere almindeligt, specifikt PBB og PBDE. Der er ingen krav vedrørende bromerede flammehæmmere i printkort og mindre plastdele i elektroniske apparater. Det svenske TCO 95 mærke, som anvendes til computere, kræver at der ikke indgår organisk bundet brom i dele større end 25 g. Miljømærkerne, og især TCO 95, må formodes at have en væsentlig indflydelse på den udvikling, der er sket med hensyn til erstatning af bromerede forbindelser i kabinetter til elektronik.

Alternativer til bromerede flammehæmmere

Der findes en lang række flammehæmmere, der kan anvendes i stedet for bromerede flammehæmmere. Til de fleste formål vil de i forhold til de bromerede flammehæmmere for en umiddelbar betragtning have visse ulemper.

Blandt alternativerne findes en række chlorholdige produkter, men det er i undersøgelsen valgt at fokusere på halogenfrie alternativer. De bromerede flammehæmmere deler sammen med andre typer af halogenholdige produkter den egenskab, at der ved brand kan dannes giftige og korrosive gasser. I forbindelse med produktudvikling fokuseres der derfor oftest på såvel chlor som brom.

Alternativerne kan opdeles i tre hovedgrupper: organiske fosforholdige flammehæmmere, kvælstofholdige flammehæmmere og uorganiske flammehæmmere. I praksis anvendes ofte kombinationer af flere flammehæmmere. De konkrete forbindelser, der anvendes, er i mange tilfælde holdt fortrolige.

Af tabel 3 fremgår - opdelt på materialer - i hvilket omfang der i dag findes kommercielt tilgængelige alternative materialer. Tabellen er hvad angår alternativer ikke dækkende, idet der kan være flere alternativer end de nævnte. Der er i tabellen medtaget materialer, hvor der i dag ikke bruges bromerede flammehæmmere i dansk produktion, men hvor bromerede flammehæmmere kan forekomme i importerede varer. Selv om der i princippet findes alternativer for det enkelte materiale kan der godt være særlige anvendelser af materialet, hvor alternativerne ikke umiddelbart vil opfylde de tekniske krav.

Til materialer, hvor der ikke findes halogenfrie kvaliteter, eller hvor der i praksis ses et skift til andre materialer i forbindelse med substitution, er der i tabellen angivet, hvilke halogenfrie materialer der kan anvendes i stedet.

Tabel 3
Halogenfrie flammehæmmere i kommercielt tilgængelige materialer.

Væsentlige anvendelsesområder, hvor alternativer endnu er på udviklingsstadiet, er indkapsling af elektroniske komponenter samt plastdele af PBT/PET. Der har en årrække været gjort forsøg med halogenfri PBT/PET, men der er endnu ikke velgennemprøvede alternativer på markedet. Til flammehæmmet ekspanderet polystyren findes der i dag heller ingen alternativer. I Danmark anvendes der til de formål, hvor der i udlandet anvendes flammehæmmet ekspanderet polystyren, imidlertid andre tekniske løsninger.

Den bedste målestok for om alternativerne umiddelbart kan anvendes, er om der findes produkter på markedet, hvor alternativerne er anvendt.

Når man ser på slutprodukterne vil stort set alle produkter, som indeholder elektronik, indeholde bromerede flammehæmmere. Det vil sige, at der stort set ikke findes elektroniske produkter og transportmidler på markedet uden bromerede flammehæmmere. Dette afspejles i, at ingen af de gældende miljømærker stiller krav om, at elektroniske produkter skal være helt fri for bromerede flammehæmmere. Et sådant krav stilles kun til byggematerialer. Svanemærket for kaffemaskiner, som er under udarbejdelse, vil formentlig kræve at bromerede flammehæmmere ikke anvendes. Der findes elektriske maskiner som fx kaffemaskiner, hårtørrere, kogekedler uden bromerede flammehæmmere på markedet, men de vil normalt ikke være mærket og markedsført som sådan.

I tabel 4 er givet en oversigt over, i hvilken grad der findes produkter eller komponenter uden bromerede flammehæmmere. Eksemplerne dækker mere end 90% af brugen af bromerede flammehæmmere.

Vurdering af alternativer

Det har været uden for rammerne af denne undersøgelse at lave en indgående miljø- og sundhedsvurdering af alternativer. De fleste af alternativerne er kun undersøgt i meget begrænset omfang, og der findes ingen omfattende risikovurderinger af nogle af stofferne. Flere af stofferne er påvist at have uønskede miljø- og sundhedsmæssige effekter, og de organiske fosforforbindelser er påvist at fordampe i målelige koncentrationer fra produkter i brug. Et større kendskab til alternativernes miljø- og sundhedsmæssige egenskaber vil være hensigtsmæssigt i forhold til en eventuel substitution af bromerede flammehæmmere.

Fra et forbrugersynspunkt vil det være af betydning, at stofferne ikke afgives under brug. I den sammenhæng vil en række af de uorganiske stoffer eller stoffer, som reaktivt er indbygget i polymerstrukturen, være at foretrække. De formodentligt mest uproblematiske uorganiske forbindelser, aluminium trihydroxid og magnesium hydroxid, bliver i dag anvendt til mange formål, men er til en del formål vanskelige at bruge, da de i væsentlig grad ændrer plastmaterialernes tekniske egenskaber.

Tabel 4
Oversigt over i hvilket omfang halogenfrie materialer og produkter er kommercielt tilgængelige.

1. Introduction to Brominated Flame Retardants

1.1 Flame retardants
1.2 The Chemistry of Brominated Flame Retardants
1.2.1 Polybrominated Diphenyl Ethers
1.2.2 Polybrominated Bipenyls
1.2.3 Tetrabromobisphenol A and Derivatives
1.2.4 Hexabromocyclododecane
1.2.5 Other Brominated Flame Retardants
1.3 European and Global Consumption of Flame Retardants
1.4 Emission from Products in Service

1.1 Flame retardants

Flame retardants are added to polymeric materials, both natural and synthetic, to enhance the flame-retardancy properties of the polymers.

There are four main families of flame-retardant chemicals:

Global production figures and trends in consumption are discussed further in section 1.3.

About 350 different substances used as flame retardants are described in the literature. The index of Flame Retardant /13/, an international guide to more than 1000 products by trade name, chemical, application, and manufacturer, contains more than 200 chemicals used in commercial flame retardants. A comprehensive list of flame retardants is compiled by the Swedish National Chemical Inspectorate /14/.

Mechanisms of action

Depending on their nature, flame retardants can act chemically and/or physically in the solid, liquid or gas phase. They interfere with combustion during a particular stage of this process, e.g. during heating, decomposition, ignition or flame spread.

Substitution of one type of flame retardants with another consequently means a change in the mechanisms of flame retardancy.

Halogen containing flame retardants act primarily by a chemical interfering with the radical chain mechanism taking place in the gas phase during combustion. High-energy OH and H radicals formed during combustion are removed by bromine released from the flame retardant.

Although brominated flame retardants are a highly diverse group of compounds the flame-retardancy mechanism is basically the same for all compounds. However, there are differences in flame-retardancy performance of the brominated compounds, as the presence of the compounds in the polymer will influence the physical properties of the polymer.

In general aliphatic bromine compounds are easier to break down and hence more effective at lower temperatures, but also less temperature resistant than aromatic retardants.

Aluminium hydroxide and other hydroxides act in a combination of various processes. When heated the hydroxides release water vapour that cool the substrate to a temperature below that required for sustaining of the combustion processes. The water vapour liberated has also a diluting effect in the gas phase and forms an oxygen displacing protective layer. Additionally the oxide (e.g. AlO2) forms together with the charring products an insulating protective layer.

Phosphorus compounds mainly influence the reactions taking place in the solid phase. By thermal decomposition the flame retardant are converted to phosphorus acid which in the condensed phase extract water from the pyrolysing substrate, causing it to char. However, some phosphorus compounds may, similar to halogens, act in the gas phase as well by a radical trap mechanism.

Nitrogen based flame retardants as melamine and melamine derivatives act by intumescence. The flame retardants are most often used in combination with other flame retardants. Gasses released from the compounds make the material to swell forming a insulating char on the surface.

A distinction is made between reactive and additive flame retardants.

Reactive flame retardants are built chemically into the polymer molecule, together with the other starting components. This prevents them from bleeding out of the polymer and vaporise and their flame retardancy is thus retained. They have no plasticising effect and do not affect the thermal stability of the polymer. They are used mainly in thermosets, especially polyesters, epoxy resins and polyurethanes (PUR) in which they can be easily incorporated.

The most used reactive brominated flame retardants are tetrabromobisphenol A (TBBPA), tetrabromophthalic anhydride, dibromoneopentylglycol, and brominated styrene.

Additive flame retardants are incorporated in the plastic either prior to, during, or, more frequently, following polymerisation. They are used especially in thermoplastics as ABS, HIPS, PS, PC and thermoplastic polyesters. If they are compatible with the plastic they act as plasticisers, otherwise they are considered as fillers. They are sometimes volatile and can tend to bleed, so their flame retardancy may be gradually lost. High molecular weight products are developed to enable plastics to be made more permanently fire retardant by the additive method.

The most used additive brominated flame retardants are polybrominated diphenyl ethers (PBDEs), Tetrabromobispehol A (mostly used as reactive FR) and hexabromocyclododecane (HBCD).

Synergism   

Combinations of flame retardants can produce an additive or synergistic effect. While the additive effect is the sum of the individual actions, the effects of synergism are higher than this sum.

Antimony trioxide    

Antimony trioxide, Sb2O3, the main antimony compound used commercially, shows no perceptible flame-retardant action on its own. Together with bromine-containing compounds, however, it produces a marked synergistic effect. Antimony trioxide is widely used in brominated FR formulations.

1.2 The Chemistry of Brominated Flame Retardants

Brominated flame retardants (BFRs) may in accordance with the classification in section 3.1 be defined as non-organophosphorus organic compounds where one or more hydrogen atoms are replaced by bromine. BFRs are usually containing 50-85% of bromine (by weight, the contents of each compound is shown in table 1.1).

Ammonium bromide, which may be used as flame retardants in textiles, and brominated organophosphates are not included under this definition.

Brominated flame retardants can be divided into three classes:

Physical/chemical properties of more than 40 brominated flame retardants in commercial use, according to OECD 1994 , IPCS 1997 and product literature are listed in appendix 3.

Until now risk evaluations have mainly focused on the high volume aromatic compounds.

In this report consumption and disposal of flame retardants will be estimated for the following groups of brominated flame retardants:

The first three groups are aromatic compound whereas hexabromocyclododecane is a cycloaliphatic compound.

1.2.1 Polybrominated Diphenyl Ethers

Brominated diphenyl ethers are a group of aromatic brominated compounds in which one to ten hydrogens in the diphenyl oxide structure are replaced by bromine.

The polybrominated diphenyl ethers (PBDEs) with three to ten bromine atoms are used in commercial flame retardants. The compounds are designated tri (3), tetra (4), penta (5), hexa (6), hepta (7), octa (8), nona (9) and decabromodiphenyl ether.

Commercial products are not pure substances. Three different flame retardants are commercially available. They are referred to as penta-, octa- and decabromodiphenyl ether, but each product is a mixture of brominated diphenyl ethers.

Synonyms   

Various synonyms and abbreviations of polybrominated diphenyl ethers are used in the literature. In this report - in accordance with the monograph from IPCS /7/ - the chemical name polybrominated diphenyl ethers is used. To indicate that it is a group of compounds the abbreviation PBDEs is used instead of the more widespread PBDE. The same group may as well be named polybrominated biphenyl ethers (PBBEs), polybrominated biphenyl oxides (PBBOs), or polybrominated diphenyl oxides (PBDOs).

Global consumption   

The annual global consumption of all polybrominated diphenyl ethers was in 1992 estimated at 40,000 tonnes, which was broken down as 30,000 tonnes (75%) of decabromodiphenyl ether, 6,000 tonnes (15%) of octabromodiphenyl ether and 4,000 tonnes (10%) of pentabromodiphenyl ether /7/. The 40,000 tonnes corresponded to about 30% of the world market.

Data on the Western European market of flame retardants shown in table 1.5 indicate that the consumption of PBDEs until 1996 did not show a significant decrease, and PBDEs accounted for about 26% of the European market for brominated flame retardants in 1996 /19/. A market analysis from 1999 shows that the market share of the PBDEs has deceased to about 11% in 1998. The decrease in the consumption of PBDEs is especially pronounced in Germany, The Netherlands and the Nordic countries /18/.

In 1986 members of the German Association of Chemical Industries voluntarily stopped the production of PBDEs and PBBs /15/. In the recent year leading European companies in the electric and electronic industry have proclaimed an official policy of avoiding PBDEs and PBBs in their products.

Environmental Health Criteria monograph has been prepared for polybrominated diphenyl ethers in 1994 /7/.

Decabromodiphenyl ether   

Decabromodiphenyl ether (DeBDE) is a fine, white to off white crystalline powder. IPCS reported that a typical composition for modern products would be 97-98% decaBDE with 0.3-3.0% of other brominated diphenyl ethers, mainly nonaBDE /7/.

Decabromodiphenyl ether is mostly used for applications in plastic and textiles. It is an additive flame retardant, i.e. it is physically combined with the material being treated rather than chemically combined.

As for the PBDEs as a group, various names and abbreviations are used for decabromodiphenyl ether. Box 2.1 gives the chemical names and synonyms of the compound. Physical and chemical properties can be found in appendix 3.

Box 1.1
Decabromodiphenyl ether

Figure 1.1
Chemical structure of decabromodiphenyl ether

Industry information indicates that decabromodiphenyl ether is used at loadings of 10-15% weight in polymers and is always used in conjunction with antimony trioxide /3/. Traditionally the major application for decabromodiphenyl ether has been in high impact polystyrene (HIPS) used for TV-set backplates. In the beginning of the 1990'ies the total global consumption of DeBDE was broken down as follows /11/:

30%   Polystyrene (HIPS) [moulding parts, panels, housing ]

20%   Terephthalates (PBT, PET) [moulding products, connectors, switchgears, electrical equipment]

15%   Polyamides (PA) [injection moulding, contactors, bobbins, electrical elements]

10%   Styrenic rubbers (SBR) [latex, carpet backing, furniture]

5%    Polycarbonates (PC) [moulding parts, panels, housing, computers, aircraft]

5%    Polypropylene (PP) [injection moulding, capacitors, TV, electronics]

15%   Other polymer applications and end uses, notably: Acetate copolymer (EVA) [extrusion, coating, wire, cables, electrical distribution] and unsaturated polyester resins (UPE) [moulding compounds, panels, boxes, electrical equipment]

It should be noted that consumption of PBDEs has changed significantly in Europe during the last years as discussed in the following chapters. For many uses PBDEs have, however, been substituted by other brominated flame retardants and the brake down of the consumption shown above still gives some indication of the use of additives BFRs by plastic raw material.

Octabromodiphenyl ether   

The commercially supplied octabromodiphenyl ether (OcBDE) is an off-white mixture of brominated diphenyl ethers typically consisting of 31-35% octaBDE. The other main components are hexaBDE (10.5-12%), heptaBDE (around 44%), nonaBDE (9.5-11.3%) and decaBDE (0-0.7%) /7/. The product is a solid of low water solubility and vapour pressure.

Chemical/physical properties are listed in appendix 3.

The chemical structure of octabromodiphenyl ether is shown in figure 1.2. On the basis of the chemical structure there are 12 possible isomers of octaBDE.

Figure 1.2
Chemical structure of OcBDE

Information provided by industry to the EU risk assessment /4/ indicates that octabromodiphenyl ether is always used in combination with antimony trioxide. In Europe it is primarily used in acrylonitrile butadiene styrene (ABS) polymers at 12-18% weight loadings. Around 95% of the total octabromodiphenyl ether supplied in the EU (around 1990) is used in ABS. Other minor uses, accounting for the remaining 5%, include high impact polystyrene (HIPS), polybutylene terephthalate (PBT) and polyamide polymers, at typical loading of 12-15% weight. The flame retarded polymer products have typically been used for the housings of office equipment and business machines.

Pentabromodiphenyl ether   

The commercially supplied pentabromodiphenyl ether (PeBDE) is a mixture of brominated diphenyl ethers. It contains typically 50-60% pentaBDE and 24-38% tetraBDE and 4-8% hexaBDE /11/.

The chemical structure of the pure pentabromodiphenyl ether is similar to the structure of octabromodiphenyl ether, but with only five bromine atoms. Chemical names and structure, abbreviations, synonyms, physical properties, etc. are listed in appendix 3.

PeBDE has traditionally been used as an additive flame retardant in epoxy resins, polyesters, polyurethanes and textiles /7/.

1.2.2 Polybrominated Bipenyls

Polybrominated biphenyls (PBBs) are a group of halogenated hydrocarbons which are formed by substituting bromine for hydrogen in biphenyl. The bromine content can vary between two and ten.

According to OECD, decabromobiphenyl (DeBB) is the only brominated biphenyl that has been identified in commercial use /11/. The technical product contains about 97% DeBB, the rest being nona and octabromobiphenyls. The demand for decabromobiphenyl in 1992 was limited to the Benelux, France and the South European countries at a level of less than 2000 tonnes per year. The W. European market of DeBB was in 1998 about 600 tonnes (see table 1.5).

The chemical structure of decabromobiphenyl is shown in figure 1.3.

Figure 1.3
Decabromobiphenyl

DeBB has traditionally been used as additive flame retardant for styrenic polymers and engineering plastics /11/. It has also been considered a general purpose FR additive for other polymers such as unsaturated polyester (UPE) resins.

Environmental Health Criteria monograph has been prepared for polybrominated biphenyls in 1994 /6/.

1.2.3 Tetrabromobisphenol A and Derivatives

Tetrabromobisphenol A (TBBPA) and derivatives are a group of aromatic brominated flame retardants in which four hydrogens in the bisphenol structure are replaced by bromine. In all tables in the report TBBPA represent the whole group.

TBBPA and derivatives are globally speaking the most important group of brominated flame retardants in terms of actual production and demand, which in 1992 was more than 60,000 tonnes per annum cooresponding to 40% of the market. In Western Europe TBBPA and derivatives accounted for about 26% of the total market in 1998 (see table 1.5).

The group includes tetrabromobisphenol A as well as its dimethylether, dibromopropylether, bis(allylether), bis(2-hydroxyethyl oxide), carbonates and epoxy oligomer derivatives.

Chemical names and structures, abbreviations, synonyms, physical properties, etc. are listed in appendix 3.

The chemical structure of TBBPA and the dimetylether derivative are shown in figure 1.4.

Figure 1.4
Chemical structures of TBBPA and TBBPA- bis-(2-hydroxyethylether)

       TBBPA

    TBBPA bis-(2-hydroxyethylether)

TBBPA is used as reactive flame retardant in the production of epoxy resins, replacing bisphenol A, partially or totally, in the reaction with epichlorhydrin. Commercial epoxy FR resins containing 20% bromine (48% if bisphenol A is totally replaced by TBBPA) are widely used in the manufacturing of rigid epoxy laminated printed circuit boards. Other epoxy based TBBPA end uses are glass reinforced panels for construction, motor housings and terminal boards.

When TBBPA is used as a reactive flame retardant, the chemical identity of the compound is lost in the process of polymerisation. This means that TBBPA per se is not present in the final product. However, in this report the content of flame retardants in products will be indicated by the quantity of TBBPA used for production of the product.

TBBPA can be used as an additive flame retardant in acrylonitrile-butadiene-styrene (ABS), polystyrene (PS), thermoplastic polyesters (PET/PBT) and phenolic resin. In the beginning of the nineties additive use accounted for approximately 10% of the global TBBPA consumption /8/. The additive use may account for a larger part of the consumption today, but updated information have not been available.

Other TBBPA derivatives included in this group are TBBPA bis(2-hydroxyethyloxide), TBBPA bis(2,3-dibromopropyl) oxide and TBBPA bis(allyloxide), used for polyolefins, in particular polypropylene (PP) extrusion grade, surface coatings and polystyrene (PS) foams, respectively.

Environmental Health Criteria monograph has been prepared for tetrabromobisphenol A and derivatives in 1995 /8/. TBBPA is not covered by EU risk assessments.

1.2.4 Hexabromocyclododecane

Hexabromocyclododecane is a cycloaliphatic compound with six bromine atoms. The chemical structure is shown in figure 1.5.

Chemical names and structures, abbreviations, synonyms, physical properties, etc. are listed in appendix 3.

Figure 3.5
Chemical structure of hexabromocyclododecane

Hexabromocyclododecane has traditionally been used as an additive flame retardants for textiles coatings and production of flame retarded expanded polystyrene used for insulation in the building industry.

In Western Europe HBCD in 1998 accounted for approximately 14% of the total consumption of BFRs (see table 1.5).

Environmental Health Criteria monograph has not been prepared for hexabromocyclododecane, but the compound is under risk assessments within the EU. A draft of the risk assessment has been finished by March 1999.

1.2.5 Other Brominated Flame Retardants

The above mentioned brominated flame retardants represented about 76% of the 1992 global production of BFRs. The remaining is covered by a number of other retardants.

More details on the consumption of the flame retardants in Western Europe is given in the following chapter. The mentioned flame retardants only represented about 52% of the W. European market in 1998.

In table 1.1 the globally speaking most widely used BFRs are listed.

CAS number, application and properties of the flame retardants are listed in appendix 3.

Table 1.1
Most widely used brominated flame retardants (based on /11/)

1.3 European and Global Consumption of Flame Retardants

As it will be shown in chapter 6 imported products account for about 90% of the consumption of brominated flame retardants with end products in Denmark. As background information for the assessments of the content of brominated flame retardants in imported products, analyses of the World and Western European market for flame retardants will be discussed in the following section.

Use of bromine   

World production of bromine in 1996 is estimated at 440,000 tonnes /16/. Brominated flame retardants accounted in 1997 for approximately 30% of global bromine consumption /17/.

In 1992 brominated the flame retardants accounted for approximately 20% of the global bromine consumption. Other uses were agrochemicals and sanitary (15%), gasoline additives (14%), drilling fluids (10%), dyes (8%), water chemicals (6%), photographic chemicals, pharmaceuticals, synthetic rubbers, minerals separation and electrolytes /11/.

Production of brominated flame retardants

Brominated flame retardants are produced by a few major manufacturers. The world's major BFR manufacturers are Great Lakes Chemical (USA), Albemarle Corporation (USA) and Dead Sea Bromine Group (Israel). More than 70% of the market in the USA and Western Europe are held by these companies /17/.

World consumption of brominated flame retardants increased from 1992 to 1995 from around 150,000 tonnes/y to 200,000 tonnes/y representing 22% of the world consumption of flame retardants (see table 1.2). According to an analysis from Roskill Information Services, the consumption is expected to have grown to around 254,000 tonnes/y by the year 2000. The growth is expected to be fastest in Asian countries other than Japan.

Table 1.2
Global consumption of flame retardants according to base element content 1992 /11/ and 1997 /17 /

The global consumption of 150,000 tonnes in 1992 can, according to OECD 1994 /11/, be broken down to approx. 40% TBBPA, 20% DeBDE, 4% OcBDE, 3% PeBDE, <1,5% PBBs, and finally 34% other flame retardants. This consumption pattern has presumably changed during recent years as will be shown for the Western European market in the following.

Brominated flame retardants are primarily used in plastics. Of the world consumption, applications other than for plastics account for less than 25% /17/. Other applications are for textiles, adhesives, rubbers, paints, wood treatment and paper. Although textiles represent a growing market because of more stringent fire safety regulations, BFRs have become less popular in this sector of the market than some of the other flame retardants /17/.

Market volume figures for Western Europe according to two different market analyses are shown in table 1.3. The two analyses refer to 1996 and 1998, respectively, and estimate that brominated flame retardants accounted for about 15% and 18% of the total market volume.

Table 1.3
Western European market for flame retardants 1996 and 1998 according to two different market analyses

A first estimate on the consumption with finished products in Denmark can be obtained by assuming that the Danish consumption pattern equals a W. European average. This first estimate will later in the report be compared to the estimates obtained by the more detailed assessment. The comparison is done to secure that all the main applications are covered by the detailed assessment.

The total population in W. Europe is approximately 390 million of which Denmark accounts for 5.3 million corresponding to 1.4%. The GNP per capita is a little higher in Denmark than the W. European average. If it is assumed that the consumption in Denmark accounted for 1.5% of the consumption in W. Europe, the total consumption of brominated flame retardants in Denmark 1997 should be approximately 600-800 tonnes. In the summary in chapter 6 this quantity will be compared to the result of the present analysis.

Consumption of BFRs in Western Europe

In table 1.4 the consumption by type of brominated flame retardant in Japan and Western Europe is shown.

The total consumption of brominated flame retardants in Japan 1994 was 51,450 tonnes - higher than the total consumption in Europe. The flame retardants may be used for production of compounds exported to other countries in the area.

It is noteworthy that the PBDEs take up a significant higher share of the European market in 1996 than of the Japanese in 1994. TBBPA and derivatives accounted for 65% of the Japanese market presumably reflecting the consumption of brominated flame retardants for electronics.

The market analysis will be encumbered with uncertainty and the differences between the 1996 and 1998 analyses may partly be due to the uncertainty of the analyses partly be due to changes in the consumption pattern during the period.

Table 1.4
Market volume for brominated flame retardants in Japan and Western Europe

According to a market analysis of Frost and Sullivan 1997, no pronounced changes in the consumption pattern are forecast for the period until 2003 /19/. The analysis of IAL consultants forecast a general increase in the market for brominated flame retardants with a minor decrease in the market for PBDEs (-1% growth p.a.) and brominated polyols (-2% growth p.a.).

A more detailed consumption estimate of the W. European market for brominated flame retardants is shown in table 1.5.

Table 1.5
Western European market for brominated flame retardants, 1998 (based on IAL Consultants /18/)

Regional differences

According to the market analysis by IAL Consultants there are significant regional differences in the use of PBDEs. In France and the UK PBDEs accounted in 1998 for 19% and 22%, respectively, of the total market of BFRs, whereas the PBDEs only accounted for 4% of the total in Germany. On the Nordic market the consumption of PBDEs is indicated as 'small unquantifiable consumption'. In the analysis of Frost and Sullivan (1996 data), there was no significant differences in the use of PBDEs in Germany and the other European countries. This may be due to a mistake in the analysis or reflect a significant shift away from the use of PBDEs in Germany during the period 1996 to 1998.

Market volumes by base material

For about half of the market volume there is a nearly 100% connection between a single flame retardant, a polymer base material and an application. This is the fact for TBBPA (epoxy for printed circuit boards and electronic component encapsulates), brominated polyols (rigid PUR foam for insulation) and HBCD (EPS/XPS for insulation panels).

The other flame retardants may be used for a number of base materials and a number of flame retardants may be used for the same base material.

Of special interest for the estimate of BFRs with imported products in the next chapter is the distribution between PBDEs, PBBs, TBBPA derivatives and other BFRs for polyolefins and engineering plastics. Of the additive BFRs (except HBCD used for XPS and EPS) PBDEs accounted for about 24%, PBBs for 2%, TBBPA derivatives for 11% whereas other flame retardants accounted for the remaining 62%. Few years ago the PBDEs made up a significant higher part.

A detailed estimate on the market of brominated flame retardants by base materials is shown in table 1.6. For each base material the percentage of the total consumption of flame retardants that is accounted for by BFRs and antimony trioxide is additionally shown. Antimony trioxide is often used in combination with BFRs, but may for instance in PVC be used in other combinations or solely.

BFRs (in combination with antimony trioxide) are the sole flame retardants used for PBT/PET, PC and EPS/XPS. For ABS, HIPS, PA and epoxies BFRs (and antimony trioxide) account for about half or more of the consumption of flame retardants.

The consumption of BFRs for phenolics, PVC, rubbers, coatings, functional fluids (for paints) and timber is in the market analysis indicated as small and unquantifiable.

The flame retardants are predominantly used reactively in epoxies, PUR and UP. The consumption for these base materials was about 36% of the total BFR consumption.

Table 1.6
Western European market for brominated flame retardants by base material 1998 (based on IAL Consultants 1999 /18/)

Consumption by end products

The use of flame retardants for the production of electric and electronic equipment in Europe in 1995 has been reported in a booklet from the Association of Plastics Manufacturers in Europe /20/. The consumption of flame retarded plastics and the percentage of flame retarded plastics containing BFRs are shown in table 1.7

The assessment shows that nearly half of the brominated flame retardants used by the EEE industry in 1995 were used for consumer electronics (brown products); particularly external parts of TV sets. Of the plastics used for consumer electronics 55% was flame retarded; of this 83% with brominated flame retardants. As it will be discussed in section 2.2.2 TV sets and other consumer electronics are not estimated to account for such high share of today consumption. This is in accordance with the market volumes shown above where ABS and HIPS (traditionally used for consumer electronics external parts) only account for 14% of the total W. European consumption of BFRs.

The data on consumption of flame retardants for the production of 'electrical equipment materials', as well as small and large domestic appliances will be included in the estimate of BFR consumption with these products in Denmark in chapter 4.

Table 1.7
Consumption of plastics treated with flame retardants for production of electric and electronic equipment in Western Europe, 1995 (after /20 /)

1.4 Emission from Products in Service

The emission of flame retardants to the in-door environment from products in service has during the last years been a focal point in the debate about the use of brominated flame retardants.

The available data do not allow detailed estimates on the emission from single product groups, but in the following the total emission from products in use in Denmark will be estimated. The estimate will only give the order of magnitude of the emission.

Emission to the air and waste water from industrial processes is included in section 2.1.5.

Significance of the emission

The significance of the emission of brominated flame retardants from office machines has be demonstrated by the detection of the compounds in the in-door atmosphere of office rooms, computer halls /22 / and control rooms /22/.

The most obvious sources of emissions to the air would be from products where the flame retardants are used as additive. Phenol-paper laminates used for printed circuit boards in consumer electronics or thermoplastic components that heat up during operation, e.g. computer monitors, could be good candidates. Unreacted flame retardants from reactive use in for instance printed circuit boards may also be emitted.

The present studies of BFRs in the in-door atmosphere cannot, however, be used for quantitative estimates of emission rates. Emission rates can be estimated from chamber experiments or may be estimated based on volatilisation models and physico-chemical properties of the compounds.

The most straight way to estimate long-term emissions of bromine compounds from the plastics would be to analyse the total bromine content of the same plastics with e.g. a 10 years intervening period. Such analyses are unfortunately not available.

Chamber experiments   

Only a few chamber experiments have been performed.

Ball et al. (1991) analysed the emission of PBDEs, dibenzofurans and dibenzodioxins from three printers, two TV sets and two computer monitors /22/. The units were flushed with 85-100 m3 of air over a period of 3 days. The temperatures within the TV sets and monitors were 36-39°C and 46-48°C, respectively. Very different results were obtained from the products. Total PBDE emission from each of the two TV sets was 192 and 4 ng PBDE/unit, respectively, whereas the emission from each of the monitors was 9 and 889 ng PBDE/unit, respectively. Only small amounts of PBDEs were emitted from the printers. The TV sets and monitors emitted predominantly tetra-BDE and penta-BDE. Both compounds are present in commercial PeBDE and OcBDE. Analysis of TBBPA was not performed in the experiment. The content of flame retardants in the products was not determined, and the explanation for the low values in one of the TV sets and one monitor could be that other BFRs were used as flame retardants in these units. This is supported by the fact that no correlation between the concentration of PBDEs and dibenzofurans and dibenzodioxins was found. The highest values of dibenzofurans and dibenzodioxins were found in the monitor with an emission of only 9 ng PBDEs.

If the highest emission values of the TV set are assumed to represent a unit where PBDEs are used in the back-plate, the total content of the unit can be roughly estimated at 180 g (12% of 1.5 kg plastic in the back-plate /32/). If the emission rate of 192 ng/unit/3days is extrapolated to a total service-life of 10 years, around 0.2 g PBDEs will be emitted during the service-life. This corresponds to 0.1% of the total content.

In the PC-monitor with high PBDE emission, PBDEs are assumed to be present in the casing of the monitor. On average a PC monitor contains about 340 g PBDEs (20% of 1.7 kg plastic in the housing /32/). If the emission rate of 889 ng PBDE/unit/3days is extrapolated to a total service-life of 10 years, some 1.4 g PBDEs will be emitted during the service-life. This corresponds to 0.4% of the total content.

From a study on the formation of polybrominated dibenzofurans and dibenzodioxins sponsored by the bromine industry /23 / a few unpublished analyses of PBDE emission from TV sets are available /24/. From two TV sets on average 35 ng tetra-BDE and 27 ng penta-BDE were emitted during 24 hours of operation with 18m3 of air passing. The cabinets of the TV sets were flame retarded with DeBDE, but no data on this compound are reported.

Unreacted TBBPA in epoxy laminates

TBBPA and other BFRs when used as reactive flame retardants will be incorporated in the polymer structure and not be present as a chemical entity in the product. Unreacted TBBPA from epoxy laminates may be emitted, but analyses performed on pulverised epoxy laminates have shown that only around 4 mg unreacted TBBPA could be extracted per g of TBBPA in the laminate. This corresponds to 0.0004%. The values are - according to the authors - probably underestimated due to incomplete extraction, but the result indicates that emission of unreacted TBBPA from epoxy laminates may be insignificant in comparison to emission from phenol-paper laminates and other plastics in which the flame retardants are used as additive.

Model estimates

The experimental data shows that significant amounts of PBDEs are emitted from the appliances. Considering the few available experimental data, the emission estimate will be based on theoretical considerations.

The emission of brominated flame retardants from products in service will depend on two factors:

Volatility

The possible emission of PBDEs per year from products in service is in the ongoing EU risk assessments estimated from the following equation:

Emission by volatilisation = 1.1 · 106 · P%

where P = vapour pressure of flame retardant (mmHg at 20°C)

The equation is derived for the loss of plasticiser additives in various plastics films, but is used in the assessments in the absence of other information.

Table 1.8 shows the vapour pressure of the compounds and the calculated annual emissions.

The emission of DecaBDE is calculated to be 0.4% over a ten year period. Compared to the above estimates from the chamber experiments of 0.1 and 0.4% per ten year, respectively, the model estimate of DeBDE seems not to be unreasonable.

Table 1.8
Vapour pressure and estimated emission of PBDEs from plastics

The above mentioned equation is derived from 'Use category document. Plastic additives'. The revised draft version of the document from 1998 /25 /, uses the following worst case emission factors for organic flame retardants.

Indoor service, volatility to the atmosphere :    0.05%

Indoor service, leaching to liquid waste:    0.05%

Outdoor service, volatility to atmosphere:    0.05%

Outdoor service, leaching to environment:    0.7%

The emission factor for organic flame retardants is taken to be similar to that of the least volatile of plasticisers and antioxidant groups.

The relatively high factor for leaching to liquid waste from indoor service seems to be a heritage from the plasticisers (in flooring) that do not apply on flame retardants. The factor for leaching to the environment from outdoor service will later be discussed in relation to flame retardants in roofing.

TBBPA

The vapour pressure of TBBPA is by Perenius 1995 stated to be 4.15·10-5 mm Hg (no temperature specification) /26/. It has not been possible to confirm the vapour pressure values from other sources. If a value of 4.15·10-5 mm Hg is put into the equation above, 46% of the content should be emitted per year. Although the calculated emission factor seems to be unreasonably high, the calculation calls for analyses of the actual emission rates of TBBPA used as additive.

Migration in the polymer

The long-term emission of flame retardants from the plastics will also be dependent on the migration of the flame retardants in the polymer. Reactive flame retardants used in thermosets are assumed to be totally bound in the polymer structure, but additive flame retardants may be considered plasticisers and will be able to migrate through the polymer structure. Migration of flame retardants to the surface of the plastics, designated "blooming" cause problem to the application of DeBDE in some polymers /27/.

Brominated flame retardants are large molecules, and the migration must be expected to be slow. No actual long-term migration rates of flame retardants in plastics have been found. In the absence of data it will be assumed that the migration is fast enough to support the evaporation of flame retardants from the surface.

Total emission

For a calculation of the total emission of BFRs from products in service in Denmark it is necessary to know the total amount of flame retardants in products in service in the society. As the consumption of the flame retardants has changed over the years, an account of the brominated flame retardants accumulated in the Danish society cannot be extrapolated from the current consumption figures.

It seems more reasonable to extrapolate the accumulated amount from European consumption figures under the assumption that the Danish consumption with end products a few years back did not differ that much from the average W. European consumption.

For the calculation it will be assumed that the accumulated amount of BFRs in products in service in 1997 corresponded to 10 years consumption. The average annual consumption is estimated at 1.5% of the W. Europe consumption in 1992 corresponding to 500 tonnes BFRs. The distribution of the flame retardants is estimated from the global distribution according to the OECD 1994. Emission factors for PBDEs are derived from table 1.8. It is in the calculation assumed that the vapour pressure of the main congener of each commercial flame retardants is representative for the commercial flame retardant, i.e. the vapour pressure of pentaBDE is used for PeBDE. The general emission factor from /25/ is used for TBBPA and other flame retardants used as additives. The emission from TBBPA and other flame retardants used as reactives is assumed to be 0. The share of TBBPA used as additive is derived from IPCS /8/, whereas the distribution for "other" BFRs are roughly estimated by the authors.

Under these assumptions the total emission is estimated at 1.5 tonnes as shown in table 1.9.

If the general value of 0.05% is applied for all flame retardants used as additives, the total amount to 1.2 tonnes.

The estimate is very uncertain. The used emission factors are considered worst case factors, and the real emission may be significantly lower. It will roughly be estimated that the right value probably will be within a factor of 10 of the calculated worst case value. The total emission is consequently estimated to be 0.2-1.5 tonnes per year.

The worst case estimates place a flag on the issue and call for more data on the emission of additive flame retardants from products in use.

Table 1.9
Estimated worst case emission of brominated flame retardants from products in service in Denmark 1997

Fate of the BFRs after emission

The major part of BFR containing products is used indoors and the emission will initially be to the indoor environment. When emitted the flame retardants are likely to adsorb to particles. The particles (dust) may adhere to surfaces within appliances, on other surfaces in the indoor environment or may be spread to the outdoor environment by airing of the rooms.

PBDEs in air samples and on atmospheric particles of rooms with a very high content of electronics (control rooms) have been analysed by Ball et al. (1992) /22/. The concentration in the dust of four analysed rooms ranged from 0.5 to 3 mg PBDEs per g dust (blank control was 0.0003 mg/g). All PBDEs from tetraBDE to decaBDE were present in significant amounts in the dust. The total PBDE concentration in the air from the four rooms ranged from 96 to 969 pg/Nm3 (blank: 0.06 pg/Nm3).

Bergman et al. has demonstrated the presence of TBBPA and PBDEs on particles in offices and a computer hall. The concentrations of the compounds were not determined. The results are the only demonstration of TBBPA release from products in use.

BFRs in dust adhered to surfaces within a TV set have been analysed by de Boer et al. (1998) /28/. The object of the study was to quantify the possible exposure of a boy, who had been watching TV and played computer games for several hours a day in a small room. Wipe from the back wall of the TV set was reported to contain 15 and 43 mg/m2 of two nonaBDE isomers and 40 mg/m2 of one DeBDE isomer. The content of the three isomers in the side wall wipe was lower. The side wall wipe was additionally analysed for heptaBDE at a content of 3 mg/m2. Circuit boards wipe was analysed for two isomers of hexaBDE at <0.4 and 0.3 mg/m2. Analyses for other PBDEs and the concentration of the compounds in the dust were not reported.

The results demonstrate that significant amounts of brominated flame retardants may be present in the dust within electronic appliances. When the appliances are dismantled for reprocessing some of the dust will be released to the workplace air. Compared to the office environment the exposure by dismantling of the appliances may be several orders of magnitude higher. The presence of brominated flame retardants in the workplace air of a recycling company is at present studied in Sweden.

Dust released from electronic appliances when dismantled is known to cause working environmental problems. In some of the Danish recycling plants the dust of TV sets is removed in a blow chamber before dismantling.

In the absence of detailed information it will here be assumed that the brominated flame retardants emitted to the air sooner or later are released to the environment, although a significant part may be disposed of to solid waste with dust in vacuum cleaner bags, etc.

Atmospheric transport

PBDEs adsorbed onto atmospheric particles will be removed from the atmosphere by wet or dry deposition. The available monitoring data indicate that long range transport via the atmosphere may be occurring for the main components of commercial PeBDE /5/.

Photolysis

Photolytic reductive debromination of DeBDE, forming lower congeners of PBDEs, has been demonstrated in experiments. In the EU risk assessment it is concluded that this reaction in the environment is likely to be small. The atmospheric half-life of DeBDE is estimated at 94 days. Removal from the atmosphere by deposition is thus assumed to be of much higher significance than photodegradation in the atmosphere.

Consequently it will in the estimate of PBDEs in rain water in section 3.4 be assumed that emitted PBDEs will be deposited without degradation.

The fate of TBBPA in the atmosphere seems to be different from the fate of the PBDEs. A half-life value of 0.12 day has been obtained for TBBPA from photodegradation experiments (Ref. in /26/ and /8/). In the absence of other information it will in the estimate on BFRs in rain water in section 3.4 be assumed that TBBPA and derivatives emitted to the air, will be degraded before they are deposited.

2. Uses in Denmark

2.1 Chemicals and Semi-manufactures
2.1.1 Import, Export and Production as Chemicals
2.1.2 Consumption with Plastic Compounds and Masterbatches
2.1.3 Consumption with Plastic Semi-manufactures
2.1.4 Consumption with Electronic Semi-manufactures
2.1.5 Emission from Production Processes in Denmark
2.1.6 Summary
2.2 Use in Manufactured Goods
2.2.1 Printed Circuit Boards
2.2.2 Housing of Electric and Electronic Equipment
2.2.3 Other Components of Electric and Electronic Appliances and Machines
2.2.4 Lighting
2.2.5 Wiring and Power Distribution
2.2.6 Textiles
2.2.7 Building Materials
2.2.8 Paints and Fillers
2.2.9 Transportation
2.2.10 Other Uses
2.2.11 Summary
2.3 Unintended Uses as Contaminant

2.1 Chemicals and Semi-manufactures

To make it clear where different parts of the materials life cycle will be described in the report, the flow of substances is illustrated in figure 2.1., exemplified by the flow of TBBPA from the production of the chemical to disposal of electronics.

Figure 2.1
Material flow of TBBPA with electronics

In all steps there may be emissions of TBBPA to the environment and production of waste.

The substances are imported to Denmark as pure chemicals, in compounds, in semi-manufactures as laminates and printed circuit boards, in finished goods and finally in waste product. Likewise the substances can be exported in compounds, semi-manufactures, finished goods and waste products.

According to the paradigm /12/ only the consumption with manufactured products (e.g. 'consumption of electronics' in figure 2.1) is included in the total consumption figures in section 4. The consumption of TBBPA for the different production processes is mainly assessed in order to estimate emissions and waste production from the processes.

2.1    Chemicals and Semi-manufactures

2.1.1    Import, Export and Production as Chemicals

Import, export and production of brominated flame retardants as chemicals according to the trade statistics from Statistics Denmark /29 / are shown in table 2.1. Commodity data for brominated flame retardants and other bromine compounds for the period 1993-1998 are compiled in appendix 7 (not included in the printed version).

The statistic data include the high volume aromatic brominated flame retardants as PBDEs, TBBPA and TBBPA derivatives.

The net supply of these compounds in 1997 totals 29 tonnes.

Vinylbromide is not included in table 2.1 as this compound in the statistics is registered under the same commodity position as dibromoethane that is used in high quantities as gasoline additive.

Hexabromocyclododecane will be registered under the commodity position ''Halogen derivatives of other cycloalkanes, -alkenes -terpenes'. The import and export of these chemicals were 0 tonnes in 1997.

Other brominated flame retardants may be registered under commodity positions including other halogenated compounds, but it is supposed that the compounds included in table 2.1 represent the chief part of the supply of brominated flame retardants as chemicals.

The chemicals are used for compounding in Denmark. According to information from compounders it is estimated that most of the flame retardants used by compounders are reexported with compounds and masterbatchs.

It is possible that the 9 tonnes ester or anhydride of tetrabromophthalic acid is TBPA derivatives used for production of PUR foam in Denmark and thus included in the consumption with plastic raw materials in the next section, but this use has not been confirmed. It cannot be excluded that a part of the other chemicals is used by companies that use the chemicals directly in the production of plastic products, but no consumption for these purposes has been identified.

Table 2.1
Import, export and production of brominated flame retardants as chemicals in Denmark 1997 according to the trade statistics 4)

Bromine derivatives of aromatic ethers

The net supply of bromine derivatives of aromatic ethers, including the PBDEs, has decreased from about 20 tonnes per year in the period 1993-1995 to around 1 tonne in 1997 (figure 2.2). The decrease in the supply of PBDEs is in accordance with the general trend in the use of these substances.

Figure 2.2
Net supply of bromine derivatives of aromatic ethers 1993-1997 (based on appendix 7).

The net supply of pentabromomethyl benzene has in the period 1995-1997 been around 10 tonnes per year. Before 1995 the compound was registered under a commodity position including non-bromine compounds.

Other bromine compounds

The total import of bromine chemicals in 1997 was around 700 tonnes. Of these ethylene dibromide and vinylbromide accounted for 264 tonnes (presumably ethylene dibromide) and methylbromide accounted for 385 tonnes. Ethylene dibromide (EDB) is used as gasoline additive, and the import has increased markedly during the nineties.

2.1.2  Consumption with Plastic Compounds and Masterbatches

The bulk import/export of bromine containing plastic compounds are in the trade statistics registered under commodity positions including non-bromine containing compounds, and it is consequently not possible to determine the import from the statistical data.

Only brominated polystyrene (PS) is registered separately. According to the trade statistics from Statistics Denmark /29/ there was in 1997 an import of 2 tonnes brominated PS (58-71% bromine content W/W) and an export of 9 tonnes. Until 1997, brominated PS was registered under other commodity positions.

Supply

The total net supply of brominated flame retardants with polymer compounds and masterbatches in Denmark in 1997 is estimated at 130-190 tonnes (see table 2.2). The estimate is based on a questionnaire survey including 60 dealers of plastics compounds and large companies with direct import. The survey was performed in collaboration with the Danish Plastic Federation. More than 95% of the interviewees responded to the questionnaire.

Table 2.2
Import of brominated flame retardants with plastic compounds and masterbatches for production in Denmark 1997

The brominated flame retardants were used in approximately 1,300 tonnes of polymer compounds. All masterbatches and compounds are imported.

TBBPA and derivatives accounted for about 24% of the total consumption of BFRs with polymer compounds and masterbatches. The TBBPA was used as reactive FR for unsaturated polyester (UPE), and as additive FR for polybutylene terephthalate (PBT), polyethylene terephthalate (PET), and acrylonitrile butadiene styrene (ABS). Additive use accounted for approximately 99% of the TBBPA in plastic compounds.

Most of the TBBPA was used in PET/PBT for production of plugs and switches for wiring, and switches, electrogates and other parts for electronics and electric appliances and machines.

About 3 tonnes TBBPA was used in ABS for housing of telecommunication devices and about a half tonne was used in unsaturated polyester for production of laminates.

PBDEs were only used in PE compounds for production of PE-film for building applications.

HBCD was used for expanded polystyrene (EPS) for insulation sheets and for high impact polystyrene (HIPS) used for distribution boxes for wiring.

Polybrominated biphenyl was used in thermoplastic polyesters (PBT/PET) used for plastic parts in contact with live parts of electric appliances and machines.

Brominated polyetherpolyol accounting for approximately 63% of total consumption is used for PUR insulation for cold stores, refrigerator ships and containers, etc.

Other brominated compounds include brominated polystyrene in polyamide and dibromopentyl glycol in unsaturated polyester.

Trend

From 1990 there has been a trend away from the use of PBDEs in Danish production of plastic products. The PBDEs have partly been substituted by TBBPA, partly by non-brominated flame retardants.

In housings for home electronics and medical appliances, PBDE containing ABS systems has to a large extent been substituted by non-brominated ABS/PC systems, and bromine containing ABS was in 1997 only used for telecommunication devices.

The development has to some extent been forced by working environmental considerations - but the driving force has not been the brominated flame retardants. In ABS systems used for housings, brominated diphenyl ethers have traditionally been used in combination with antimony trioxide. Antimony trioxide is in EU classified as carcinogenic (R40) and in accordance with Danish regulations /30 / carcinogenic compounds are to be substituted if possible.

Bromobutyl rubber   

Brominated compounds are used for production of bromobutyl rubber. The brominated compound is not used for flame retardancy of the rubber and will not be included in this study.

Flame retardancy of rubbers is mostly obtained by the use of chlorinated compounds, antimony trioxide, lime and other fillers, but brominated compounds may be used as well. It has not been possible to identify any consumption of brominated flame retardants for production of rubber in Denmark.

According to an American producer, brominated flame retardants have been used in a variety of rubbers. Typical applications include seals, belts, tubing, wire and cable insulation, roofing, coated fabrics, and sponge.

2.1.3  Consumption with Plastic Semi-manufactures

Plastic semi-manufactures of BFR containing ABS, PE, PS, PP and PC are imported for production processes in Denmark.

The bulk part is sheets of ABS and PS for vacuum forming of components for EE appliances and the transportation industry, but also foils, pipes and bars are used.

Based on information from two leading dealers of plastic semi-manufactures the total import of flame retarded semi-manufactures are estimated at 10-20 tonnes ABS, 5-10 tonnes PS and 5-10 tonnes PE, PP and PC. Included in the estimates is direct import by manufacturers.

The used flame retardants are not known, but it is roughly estimated that most ABS is flame retarded with TBBPA, PS with HBCD and the rest with other brominated flame retardants.

In total the consumption of BFRs with plastic semi-manufactures is estimated at at 2-5.2 tonnes TBBPA, 0.1-0.3 tonnes HBCD, and 0.5-1.5 other BFRs.

2.1.4  Consumption with Electronic Semi-manufactures

Brominated flame retardants are imported with laminates for production of printed circuit boards in Denmark.

Brominated flame retardants are also imported with other semi-manufactures: Electronic components, sockets, switches, etc., but the use of these semi-manufactures is estimated not to generate waste or emissions to the environment and consequently not included in this part of the analysis.

The laminates are estimated to account for the major part of BFRs with semi-manufactures.

Laminates for printed circuit boards

In the following section terms that will be explained in more detail in section 2.2.1 will be anticipated.

There is no Danish production of laminates for printed circuit boards. The laminates are mainly imported from Sweden or Germany.

The Danish production of printed circuit boards is in the trade statistics only registered in terms of the value of the production, whereas import and export are registered with both value and weight. The weight of the production can broadly be estimated from the value/weight ratio of the export.

Using this ratio, the production of unassembled boards can be estimated at approximately 710-1100 tonnes. The laminates for the production are presumed to be covered by the commodity position "Copper foil on plastic or paper". In 1996 and 1997 the net import of these foils was 720 and 1,370 tonnes, respectively.

Based on information from producers of printed circuit boards it is estimated that 90% of the production of printed circuit boards is based on FR4 (or similar) laminates, whereas the remaining 10% includes flexible prints and FR2 prints.

FR4 laminates contain approximately 15-17% TBBPA /32,33/.

FR2 laminates produced in Europe have traditionally contained approximately 4% TBBPA /32/, but halogen-free laminates have been on the market for more than a year. It has not been possible to discover the market-share of the halogen-free FR2 boards.

No information on an average content of BFRs in flexible laminates has been available, but the total turnover is estimated to be relatively small, and the BFRs in flexible laminates will not be included in the estimate.

Under the assumption that FR4 laminates account for 90% of the consumption and that TBBPA containing FR2 laminates account for 5% of the consumption, it is estimated that 100-160 tonnes TBBPA was used for production of printed circuit boards in Denmark in 1997.

2.1.5    Emission from Production Processes in Denmark

No actual data on emission of brominated flame retardants from plastic processing in Denmark are available.

Emission of brominated flame retardants from European plastic processing industry have been included in a study on industrial emissions of BFRs carried out for the European Commission in1995 /70/. It is in the study concluded that the information from the plastic processing industry was not sufficient to make any factual comments on the amount of BFRs released to the environment.

In the lack of data, emissions will be roughly estimated using loss-factors from ‘Use Category Document. Plastic Additives’ /25/. The document provides process specific loss factors for plastic additives. The loss factors are meant to be used in the absence of actual data.

Compounding   

Initially some emissions will be to the atmosphere, but ultimately all particles will be removed or settled and losses will be to solid waste or waste water. The loss factors are dependent on the particle size. For powders of particle size <40 µm the worst case loss factor is 0.05%; for particle size >40 µm the factor is 0.01%. There is an additional loss factor for organic flame retardants of 0.002%.

It will here be assumed that the loss predominantly is to solid waste with a worst case loss factor of 0.052%. For a rough estimate, the total import of BFRs as chemicals is multiplied by this factor, giving a total loss of <0,02 tonnes. The particles are assumed mainly to be disposed of with solid waste.

Conversion

Initial losses from conversion processes will be to the atmosphere. Subsequent condensation could result in losses to liquid waste. It will roughly be assumed that half of the losses is discharged to waste water.

The volatility is in the document taken to be similar to that of the least volatile plasticiser and antioxidant groups. The losses are dependent on the process.

On the basis of volatile losses the loss factors for worst case conditions are as follows:

Open processes:    

For processing significantly in excess of 200° C or for smaller processing sites (< 750 tonnes plastic per year) loss factors should be multiplied by a factor of 10.

Closed processes include conversion of thermosetting resins, extrusion and moulding processes. Open processes include thermoforming, calendering and fibre reinforced plastic fabrication.

For a rough estimate it is assumed that all processes based on compounds are closed processes, whereas the plastic semi-manufactures are processed in open processes. The loss factors are multiplied by a factor of ten for a worst case estimate.

Using the highest estimate for the use of plastic raw material and semi-manufactures in Denmark (see sections 2.1.2 and 2.1.3), the total emission can be estimated at <0.04 tonnes in 1997. Half of this is roughly assumed to be emitted to the air; half to waste water.

The estimate is a worst case estimate; the actual emissions may be much lower.

2.1.6  Summary

Brominated flame retardants are not produced in Denmark.

The total import with semi-manufactures for production in Denmark is summarised in table 2.3. The account gives the turn over of brominated flame retardant for compounding (chemicals), extruding and moulding (plastic compounds and masterbatchs), vacuum forming (other plastic semi-manufactures) and production of printed circuit boards.

Table 2.3
Import of brominated flame retardants with chemicals and semi-manufactures for production in Denmark

The consumption of brominated flame retardants with chemicals and compounds only gives a limited information about the consumption of BFRs with manufactured goods, as most end products are exported. This is illustrated by the fact that the consumption with chemicals and compounds in Sweden is very different from the Danish volumes. In Sweden with a population twice of the Danish population, a total of 560 tonnes TBBPA per year was used as chemicals in 1992/93 for compounding and plastic production /31/. Most of this was used for production of laminates for printed circuit boards - a production not present in Denmark.

Brominated flame retardants used for production processes in Denmark are summarised in table 2.4. Physical/chemical properties of the compounds are shown in appendix 3.

Table 2.4
Brominated flame retardants used in production processes in Denmark 1997

2.2 Use in Manufactured Goods

2.2.1  Printed Circuit Boards

Printed circuit boards are assemblies consisting of a copper-foiled laminate on which small electric and electronic components, encapsulated in plastic and metal, are mounted. Both laminates and plastic for encapsulation are flame retarded, usually with brominated flame retardants.

Laminates

There are two main groups of laminates - with and without reinforcement /32 /. Flexible laminates without reinforcement represent a smaller material volume than the reinforced types. Flexible laminates are most often made of polyester or polyimid /32/. Some types are flame retarded with brominated flame retardants, but no detailed information have been available.

The reinforced laminates consist usually of either glass fibre reinforced epoxy (FR4), or cellulose paper reinforced phenolic resin (FR2), but a range of different laminates are used (FR3, FR5, CEM1, BT Epoxy, etc.).

FR4 is by far the most used laminate. The laminate typically contains about 15% TPPBA. The TBBPA content of the most used 1.6 mm FR4 laminate can approximately be estimated at 0.42 kg per m2 /33 /.

In industrial and office electronics, e.g. computers and electronics for telecommunication, the printed circuit boards are generally based on FR4 or a similar type of laminate.

By the early 1990'es European type FR2 laminates were flame retarded with TBBPA whereas Asian type FR2 laminates were flame retarded with PeBDE /32,34/. For both types the content of a typical FR2 laminate has been estimated at 0.036 kg/m2 /32/. Of recent years it seems there has been a shift away from PeBDE, and today most Asian FR2 laminates seem to be flame retarded with TBBPA (/35/ among others). In phenolic resins TBBPA is used as an additive flame retardant contrary to the reactive use in epoxy based FR4 laminates /8/. As a rough estimate it will be assumed that PBDEs still cover 30% of the FR2 laminates in consumer electronics other that TV-sets.

Traditionally printed circuit boards for TV sets and home electronic appliances have been based on FR2 /32/, but within the high-priced market segment there has been a trend towards printed circuit boards based on FR4. However, FR2 still seems to be the dominant laminate for home electronics. It will be assumed that all TV-sets contain TBBPA based FR2 (nearly all TV-sets on the Danish market is European produced).

Electronic components

Plastic encapsulation of electronic components on the board is predominantly made of epoxy resin with TBBPA /33/. Of the top ten component groups by volume, seven of the groups contain TBBPA. According to Legarth, 1996 /33/ these groups are plastic/paper capacitors, microprocessors, bipolar power transistors, IGBT power modules, ASICs, and metal oxide varistors. None of the top ten groups contains other brominated flame retardants.

The concentration of TBBPA in the plastic encapsulations is relatively low. The plastic encapsulation of an integrated circuit (chip) is reported to contain approx. 20-30% epoxy with approx. 2% TBBPA incorporated /53/.

The total content of TBBPA in encapsulated components will vary by type and an average content can only be estimated with high uncertainty. Hedemalm et al. have estimated an average value of 90 g/m2 /32/. It will roughly be estimated that the total use of flame retardants in electronic component will be within ± 50% of this value.

PBDEs and PBBs may also be present in electronic components. Analyses of PBDEs and PBBs in electronic components from 42 scrapped circuit boards assemblies in 1996 showed the presence of PBBs in the fraction 'carbon-metal resistors' and 'tantalum capacitors' and PBDEs in 'microchips' and 'capacitors' /36 /. It was only possible to extract a few percentages of the total halogen content, and the results cannot be used for an estimation of the content of the substances in the component. As the circuit boards were derived from disposed electronics, the content will represent use patterns ten years ago.

To take a possible content of PBDEs into account it will be estimated that the boards contain <10 g/m2 PBDE.

Other plastic parts

Brominated flame retardants may also be present in small plastic parts on the printed circuit board. In the above mentioned fractionation of assembled printed circuit boards, no TBBPA, PBBs or PBDEs were found in the fractions 'connection tools' and 'plastic part' (4.5% of total weight). To take a possible content into account it will be assumed that in total <4 tonnes may be present in other parts.

Production in Denmark

There is no production of laminate for printed circuit boards in Denmark.

The production of printed circuit boards, is assessed in section 2.1.4. There is both import and export of printed circuit boards. The total TBBPA content of printed circuit boards produced in Denmark in 1997 is estimated at 100-160 tonnes.

There is a net export of printed circuit boards i.e. the consumption of printed circuit boards for production of electronics in Denmark is smaller than the production of the boards.

There is in Denmark a production of consumer electronics (TV sets, radios, etc.), medical and laboratory equipment, radio- and telecommunication equipment and control and process equipment. A detailed investigation of the production is not covered by the present assessment, but the use of brominated flame retardants in produced products can roughly be estimated from a few assumptions. From the trade statistics the total supply of printed circuit boards for Danish production of electronic products can be estimated at 470 tonnes (using weight/value ratio of export for calculating the weight of the production). FR2 printed circuit boards are assumed to account for 15% of the supply, whereas FR4 is assumed to account for 80%.

Considering these assumptions, the total consumption of TBBPA with printed circuit boards for production of electronics is estimated at 55-82 tonnes in 1997.

Import/export

Approximately 90% of the electronic products produced in Denmark is exported, and similarly about 90% of the consumption is imported.

Consumption in Denmark

The consumption of brominated flame retardants in printed circuit boards in electric and electronic appliances appear from table 2.5. The total consumption is estimated to be 100-180 tonnes. The estimate is based on information on consumption of EE equipment and a rough estimate of the average content of printed circuit board in each type of equipment derived from Hedemalm et al. /32/. The detailed estimate is included in appendix 6.

The major contribution groups are office machines, control and process equipment, medical and laboratory equipment, radio and telecommunication equipment and consumer electronics.

Table 2.5
Consumption of brominated flame retardants with printed circuit board assemblies 1)

As an alternative estimation method the total content of printed circuit boards could be calculated from estimates of the average content of printed circuit boards in each group of products. This approach has been used by Legarth (1996) for printed circuit boards in EEE waste /33/. Within the range of uncertainty it would give nearly the same result. Legarth estimates the total content of printed circuit board in EEE waste in 1995 to be 3,000-5,500 tonnes, and translates this into approx. 144 tonnes TBBPA. The estimate of Hedemalm et al., using the same average content of printed circuit boards as used here, gave an estimate of 183 tonnes TBBPA in 1995 (Swedish figures divided by 1.83). Both estimates were based on the same amount of EEE waste.

Trends

The consumption of TBBPA with printed circuit boards and electronic components is increasing as a consequence of the increase in the consumption of electronic products.

For consumer electronics in which halogen-free alternatives are available on the market, the increase in the consumption of the products will to some extent be counteracted by a shift to halogen-free laminates, but the halogen-free laminates seem only to account for a minor part of the global market.

Waste from manufacturing

During the production of printed circuit boards a substantial part of the laminates is cut off and ends up in solid waste. Considering information from producers it is estimated that 15-25% of the laminates - corresponding to 15-25 tonnes TBBPA - is disposed of with solid waste.

During assembling of the circuit boards with components a few percentages of the laminates are removed by drilling, etc. This waste is assumed to be included in the 15-25% waste from production of the circuit boards.

A minor part of the products will be defective and disposed of with waste. This contribution to waste is considered negligible.

Emission from uses

Emission of brominated flame retardants from products in service is discussed in detail in section 1.4, and a total emission from al uses is roughly estimated.

From epoxy based laminates in which TBBPA is used as reactive flame retardant the emission during service is considered negligible although small amounts of unreacted TBBPA may be emitted.

By contrast the emission from paper-phenolic laminates, in which the flame retardants are used as additives, may be significant as the circuit boards heat up during operation. No profound studies of emission of TBBPA from phenolic-paper laminates exist.

Recycling and waste disposal

Printed circuit boards are ultimately either combusted during recycling of the metals or disposed of to landfills or incineration. Recycling of electronics is discussed in detail in section 3.1.1.

Substitution

Halogen-free alternatives are available for both epoxy and paper-phenolic laminates (see section 7.2.1).

Electronic components with flame retarded halogen-free plastic encapsulates have been introduced, but at present only for a very limited number of components.

2.2.2 Housing of Electric and Electronic Equipment

Housing of electric and electronic equipment - in particular TV sets and computer monitors - has traditionally accounted for a significant part of the consumption of PBDEs.

Base polymer

Housing or enclosures for computer monitors and other appliances is predominantly made from high-impact polystyrene (HIPS), ABS-polycarbonate blends or ABS based flame retardant compounds /11/, but polypropylene (PP), polycarbonate (PC) and blends of polyphenylene ether (PPE) and styrene/butadiene polymer may be used as well.

In the early nineties, HIPS represented 30% of the global DeBDE consumption, and ABS accounted for around 95% of the total OcBDE supplied in the EU.

During recent years PBDEs in housing have to a large extent been replaced by other brominated or halogen-free flame retardants. A detailed survey of flame retardants in housing of EE appliances on the Danish market is complicated by the fact that there is no general use pattern. The housing of identical products may contain different base polymers and flame retardants. To make exact estimates it is thus necessary to know the content of a large number of different products.

It has not been possible to obtain detailed information on the material content of imported products. The estimates for the major applications, TV-sets and office machines - will therefore be based on German test data. The fire safety of electronic products is regulated by the same standards in Germany and Denmark (see section 6.2.1), and it is assumed that the material content of the same brand on the two markets in general is the same.

Consumer electronics

Back panels - and to some extent the front cabinet - of TV sets are usually made of flame retarded materials. In the USA and Japan brominated flame retardants are still used in back panels and front cabinet (USA) of TV sets, but in TV sets purchased in Europe the front cabinet does not contain flame retardants, and there is a trend away from the use of halogenated additives in back panels /37/. Based on the monitoring of the German magazine Stiftung Warentest it has been shown that the percentage of tested TV set enclosures that contained halogenated flame retardants decreased from 68% in 1994 to 8% in 1997 as shown in figure 2.3 /37 /. It should be noted that the different tests do not cover the same market segment; some of the test e.g. only include 17'' TV sets. However, the trend seems to be clear. The absence of BFRs in European TV sets and the possible effect on the flammability of the TV sets have been discussed in /37/.

Figure 2.3
Percentage of tested TV set enclosures containing halogenated flame retardants according to the journal articles (from /37/)

Most other consumer electronics - radios, videos, etc. - are considered not to contain brominated flame retardants in the housing /32,51/.

There are, however, some exceptions. At least some video camcorders on the Danish market are known to contain TBBPA in the housing.

Office machines

The housing of office machines - computers, printers, copying machines, fax machines, etc. - is made of flame retarded plastic. PBDEs have traditionally been used for flame retardancy, but during the last years TBBPA and non-halogen flame retardants have substituted for the PBDEs.

Test results of electronic products on the German market show that out of more than 150 computer monitors, notebooks (portable computers) and printers tested in 1997/98, none contained PBDEs or PBBs (the source of information is confidential). A part of the analyses is represented in table 2.6. Of the bromine containing products 72% contained TBBPA. The remaining 28% contained other not identified brominated flame retardants.

Table 2.6
Test results on brominated flame retardants in plastic parts of electronic products sold in Germany

There is a marked trend from 1997 to 1998 towards bromine-free monitor housings, especially for the more expensive 17'' monitor. It is moreover notable that there is a significant difference between the more expensive 17'' monitors - presumably for the office market - and monitors of PCs for the consumer market. Of the 17'' monitors only 1 out of 14 contained brominated flame retardants, whereas more than half of the "home-PC" monitors contained bromine. For the office market it is more usual to buy monitors with the TCO-label, controlled by the Swedish Confederation of Professional Employees (see section 6.4). The TCO-label, assigned for more than 350 monitors (Oct. 98), requires that organically bound bromine is not present in parts >25 g. The significant difference between the two monitor groups could be an effect of the labelling.

For the printers, there is a significant difference between laser and inkjet printers that may reflect the different heat generation of the two printer types. All laser printer housings contain brominated flame retardants, mainly TBBPA.

Four out of 14 notebooks contained brominated flame retardants in the housing. In one out of 13 notebooks the housing of the power supply also contained brominated flame retardants. The result indicates that the power supply of other electronics in general may not contain brominated flame retardants.

It has not been possible to obtain detailed information on copying machines. Leading companies on the market state that PBDEs are not used in machines anymore, but do not have statements on other types of brominated flame retardants. In the absence of specific information it will be assumed that the housing of copying machines like laser printers contain brominated flame retardants and that the flame retardants will be predominantly TBBPA. The Nordic Swan and the German Blue Angel require that copying machines do not contain PBBs or PBDEs in plastic parts >50 g, but there are no requirements concerning other brominated flame retardants (see section 5.4).

Fax machines are assumed to follow the same pattern as laser printers.

Some old keyboards may contain brominated flame retardants, but new keyboards do not contain these flame retardants /38/.

As to the information received from Danish producers, the housing of telephones and mobile telephones should in general not contain brominated flame retardants.

BFRs are known to be present in the housing of some modems used for Internet communication.

Medical and laboratory equipment

The consumption volume of BFRs in housing of medical and laboratory equipment may potentially be significant, but the product group is even more diverse than consumer and office electronics. Brominated flame retardants are not used any more in the housing of Danish manufactured medical and laboratory instruments, but they were, however, formerly used.

Domestic appliances

Brominated flame retardants may be present in the housing of small home appliances. According to Swedish experience, coffee machines do generally not contain brominated flame retardants in the housing /38 /, but minor plastic parts in contact with live parts of the machine will contain flame retardants (see next section). According to the assessment from APME (see table 1.7) flame retardants should only be used in inner parts of domestic appliances.

There are no specific requirements regarding housing of heat generating appliances like hair dryers and coffee machines, but the inner parts in contact with live parts may be larger in this type of appliances.

Western European consumption

The W. European consumption of BFRs for ABS and HIPS which traditionally have been used for housing of electronic equipment was in 1998 8,500 tonnes representing about 10% of the total BFR consumption (see table 1.6). This indicates that BFRs are still widely used for housing of European produced electronics.

Content of flame retardants    In previous analyses of brominated flame retardants in EEE waste in Denmark it has been assumed that the PBDE content in housing was around 18%. The test results in table 2.7 indicate that the content of brominated flame retardants in the housing is significantly lower. In table 2.7 the recommended loading for computer housing plastics (UL94 V-0 HIPS) from one manufacturer of brominated flame retardants is shown. TBBPA is not as effective as DeBDE, and higher loading is necessary to meet the V-0 requirements.

Table 2.7
Recommended loadings for UL94 V-0 (1,6mm) HIPS /39 /

From the same producer, the recommended loading of TBBPA for V-0 ABS is 20-26%. It is known from other sources that ABS for housing contains about 23% TBBPA.

The recommended loadings indicate that the applied loading of the tested appliances in table 2.6 may be too low for V-0 rating or the analyses underestimate the actual content. In the absence of more specific information it will be assumed that the test results reflect the actual content of the housing of the appliances.

Production in Denmark

Around 3-6 tonnes TBBPA are contained in ABS used for production of housing for electronics in Denmark. The ABS is imported both as plastic compounds and sheets. The casing is predominantly used for electronics for telecommunication that is exported.

Consumption

The total consumption of brominated flame retardants with housing of electric and electronic equipment in Denmark is shown in table 2.8. The total con-sumption is estimated at 80-130 tonnes.

Table 2.8
Consumption of brominated flame retardants with housing for electric and electronic equipment in Denmark 1997

Trends in consumption

Housing is the field of application where the most pronounced changes in the use of brominated flame retardants have been taking place.

In Danish production in the order of hundred tonnes of brominated flame retardants were used for housing until a few years ago.

In previous studies on waste of electric and electronic equipment (EEE waste) in Denmark it has been assumed that DeBDE accounted for approximately 100% of the flame retardants in housing. Estimates on the total content of PBDEs in EEE waste in Denmark (1995) have varied from 157 to 1,220 tonnes (see section 3.1.1).

At the early nineties DeBDE and OcBDE were the most used flame retardants for housing. Today these compounds have to a very large extent been replaced by TBBPA, other brominated flame retardants or non-halogen flame retardants in housing of electronic appliances on the N. European market.

Several factors have contributed to the development: Working environment considerations (e.g. Denmark), legislation concerning furan/dioxin formation (Germany), ecolabels, consumer awareness, and environmental policy of companies.

The reason for the substitution of PBDEs on the German market is partly the German Dioxin Ordinance (see section 5.3) that specifies the maximum allowable quantities of specified chlorinated or brominated dioxins and furans that can be present in products marketed in Germany. The dioxins and furans may be present as contaminants or be formed during intrusion, moulding or recycling of plastics containing PBDEs /10/. The levels of brominated dioxins and furans formed in the manufacture of plastics at temperatures of 150-300º C have been reported to be several orders of magnitude higher when DeBDE or OcBDE were present compared to the levels when TBBPA or bis-tetrabromophthalimide were present /10/.

Other brominated flame retardants have been designed to preclude the possible formation of brominated dioxins or furans and ensure compliance with the German Dioxin Ordinance. As an example ethylene bis-tetrabromophthalimide is marketed as a substitute for DeBDE in ABS and HIPS with reference to the German Dioxin Ordinance.

The requirements regarding brominated flame retardants of four of the most accepted and widespread ecolabels in N. Europe are described in section 5.4. With a few exceptions the Nordic Swan and the German Blue Angel only require that the housing of electronic products do not contain PBBs or PBDE, and there are no requirements regarding minor plastic parts and printed circuit boards. The most restrict requirements are stipulated by the TCO label (more than an ecolabel) that requires no organically bound bromine in parts >25 g.

Emission during production

Emission to air and waste water during production is treated jointly for all production processes in sections 1.4 and 3.4.

Emission during use

Emission during use is discussed in section 1.4. It should be noted that TBBPA is used as an additive in housing, and emission of TBBPA from computer monitors is presumably of much higher significance than emission from the printed circuit board of the computer.

Recycling and waste disposal

Housing of EE equipment is disposed of to landfills or incineration. Recycling of electronics is discussed in detail in section 3.1.1 and waste disposal in section 3.2. The plastic containing flame retardants are not recycled.

Substitution

Substitutes for brominated flame retardants are available for all kinds of housing, see section 7.2.3.

2.2.3  Other Components of Electric and Electronic Appliances and Machines

Brominated flame retardants may be present in a number of other components of electric and electronic appliances and machines:

The conceptual boundary between switches and other gear used in appliances and machines and similar components used for wiring and power distribution - included in section 2.2.5 - is not fixed, but lined up in the aim of distinguishing between short-term and long-term applications.

The sources of information that the consumption estimates will be based on do not use this distinction, and there will be some uncertainty as to the allocation of the consumption on this section and section 2.2.5.

Parts of relays, switches, pumps, etc.

Switches, relay parts, pump parts, etc. and other internal component of appliances and machines can broadly be distinguished from the housings - included in the previous section - by the used base polymers.

The main base polymer options for production of the internal components are thermoplastic polyesters (PBT, PET), polyamides (PA, nylons), polycarbonate (PC), polyphenylene sulphide (PPS) and liquid crystal polymers (LCP).

Part of relays, switches, pumps etc. are often made of PET/PBT and PA.

It has not been possible to obtain specific information on the BFR content of all these parts, and the estimates will be based on the following more general information on the consumption of BFRs with the plastic types of relevance.

DeBDE has been widely used for PET/PBT, PA and these plastics represented 20% and 15% respectively, of the total global consumption of DeBDE in 1992. This corresponds to approximately 10% of the total consumption of brominated flame retardants.

PET/PBT and PA is cf. table 1.6 estimated to account for 10% and 5%, respectively, of the total Western European consumption of brominated flame retardants in 1998 corresponding to 8,500 tonnes.

As a rough estimate the consumption in Denmark with these plastics in end-product should be of the magnitude 50-120 tonnes BFRs (cf. the estimate in section ). Parts made of these plastics will be included in this section, but are as well used for wiring and industrial automation (section 2.2.5) and in transportation (section 2.2.9).

The total consumption of flame retarded plastics used for production of ''Electrical equipment material" in W. Europe was 35,000 tonnes in 1995 of which 54% were flame retarded with BFRs (see table 1.7). The group includes circuit breakers, switches, etc., but not internal parts of appliances and machines. These applications will thus be included in section 2.2.5. The total content of brominated flame retardants in the products consumed in Denmark can roughly be estimated at 30-40 tonnes. For the estimate it is assumed that Denmark accounts for 1.5% of the W. European consumption and that the BFR content is 12-15%.

The consumption of BFRs with these plastic materials for production of EEE parts in Denmark was in 1997 around 35 tonnes. BFRs have to a large extent been replaced by other flame retardants in PA and PC used in Danish production, but they are present in imported products. According to the market analysis og IAL consultants /18/ it is mainly in the Northern European countries that the BFRs are replaced in polyamides.

Considering the present information it will be estimated that a total of 20-40 tonnes BFRs are used for these applications.

The flame retardants used will cf. section 1.3 be TBBPA and derivatives, PBBs, PBDEs and other BFRs.

Cables

Cables within electronics often contain brominated flame retardants to comply with the strict fire safety requirements of the internal parts of electronic equipment. Information has only been obtained from one major producer. The cables contain 5% bromine. The specific compound is considered confidential, but it is not PBDEs or PBBs. The 5% bromine content correspond to approximately 8% BFRs.

Moulding fillers

Flame retarded moulding fillers are used for sealing of electronics. The fillers are mostly based on epoxy or other thermoset resins. According to the Danish Product register about 1.5 tonnes DeBDE with moulding filler are annually used for production processes in Denmark. The fillers are predominantly used in professional electronics, but also electronics in battery chargers are known to contain flame retarded moulding filler.

Foam

Flame retarded PUR foam has been reported to be used in electric and electronic appliances and machines. According to manufactures BFR containing foams are not used for domestic refrigerators and freezers produced in Denmark. It has not been possible to identify specific uses, but it is assumed that there will be a small consumption with imported products.

Plastic insulation parts

Plastic parts in contact with live parts of all kind of electronic and electric equipment contain flame retardants. In heat generating appliances as hair dryers and irons, the inner parts in contact with live parts are relatively large.

Direct inquiries to agents of major producers of coffee machines, hair dryers, curling irons, electric irons, microwave ovens, and electric toasters have not revealed any specific information on the content of brominated flame retardants in these products. None of the producers have specifically stated that the product do not contain brominated flame retardants, but one producer have answered that their products do not contain PBDE and PBB.

Coffee machines do generally not contain brominated flame retardants in the housing /38/, but plastic parts in contact with live parts of the machine will contain flame retardants. In Hedemalm et al. (1995) /32/ it is roughly estimated that coffee machines contain 50 g flame retarded ABS per machine, corresponding to 10 g PBDE. With a consumption of about a half million coffee machines the total may amount to approximately 5 tonnes PBDE.

In the inventory from the APME shown in table 1.7 it is estimated that the consumption of flame retardant plastics for production of small and large domestic appliances in W. Europe was 3,000 and 11,000 tonnes, respectively. The share of brominated flame retardants is not stated, but if it is assumed that BFRs were used in 50% of the flame retarded plastics in a concentration of 15% it can be translated into about 1,000 tonnes BFRs. A part of this will be included in other groups of 18-50 this section.

The plastics used for these parts will be ABS, PP and PC among others. PP and PC accounted for 8% and 5% of the total European consumption of BFRs in 1998 (cf. table 1.6) corresponding to 8,000 tonnes.

Considering the present information it will be roughly estimated that other plastic parts account for a total consumption of tonnes flame retardants.

Production in Denmark

Approximately 35 tonnes brominated flame retardants were used in compounds of PBT/PET and PA for production of switches, relays, parts of electric machines, etc. in Denmark. Almost all was TBBPA, but PBBs and 'other flame retardants' both accounted for approximately 4 tonnes.

Table 2.9
Consumption of brominated flame retardants with other parts of electronic appliances and electric machine in Denmark 1997

Trend in consumption

In Denmark and Germany there has been a trend of substituting halogen-free flame retardants for BFRs in polyamides. For the other polymers the trend has been a replacement of PBDEs by TBBPA and other brominated flame retardants and an increase in the consumption due to a general increase in the consumption of EE equipment. For the total group the consumption is estimated to be stagnant, with two opposite-acting trends.   

The Nordic Swan and The German Blue Angel have at present ecolabels for coffee machines under development that expectedly will require that BFRs are not used at all in the machines. This reflect that small domestic appliances without BFRs are available on the market.

Emission during production    Emission to air and waste water during production is treated jointly for all production processes in section 1.4 and 3.4.

Emission during use

Emission during use is discussed in section 1.4. It should be noted that the brominated flame retardants are mostly used as an additives. Emission for other plastic parts of the equipment may be of same significance as the emission from the housing.

Recycling and waste disposal

Other plastic parts of EE equipment is ultimately disposed of to landfills or incineration. Recycling of electronics is discussed in detail in section 3.1.1 and waste disposal in section 3.2. The plastic containing flame retardants are not recycled.

Substitution

Substitutes for brominated flame retardants are available for PA and PC, but at present not for PBT/PET; see section 7.2.4 and 7.2.5.

2.2.4  Lighting

Brominated flame retardants may be present in lighting in:

Sockets

Sockets used for incandescent lamps may be made of ceramics, thermoplastics or Bakelite, a phenol based thermoset. Plastic sockets will often be made of flame retarded PBT. Some PBT sockets used for production in Denmark is known to contain 11-12% TBBPA, but it is not known whether this is general to all plastic sockets. Plastic sockets should according to a leading supplier account for about 90% of the Danish market of sockets. (Plastic sockets are by users often designated "Bakelite sockets").

Considering information from a leading importer and Danish producers of lighting, it is estimated that plastic sockets account for the major part of sockets in lamps sold in Denmark as well.

Plastic covers

Covers, shades and similar parts are to pass a glow-wire test at 650° C, if they are placed closer than 30 mm from any heated part of the lamps (see section 6.2.3). The covers may be made of flame retarded grades of PC, PMMA, HIPS or PA /11/. PA flame retarded with BFRs have previously been used by Danish producers, but today halogen-free grades are used. Often the producer of the end products do not know the specific flame retardants used is plastic parts supplied by sub-contractors. A screening of plastic parts used by a leading Danish producer revealed that bromine compounds were present in one out of 50 analysed parts. Considering the available information it is estimated that the consumption of BFRs with other plastic parts is relatively small and less than 3 tonnes. Both PBDE, TBBPA and other flame retardants may be used.

Compact fluorescent tubes

The basis of compact fluorescent tubes (energy-saving light bulbs) is often made of flame retardant plastics. It has not been possible to obtain specific information on the flame retardants in the basis, but it is most probable BFRs.

Switches

Switches is most probably made of flame retardant plastics. The switches of lighting usually only weigh a few grammes and the total amount of flame retarded plastic will be small compared to the sockets.

Other parts

Other lamp parts as capacitors for fluorescent tubes of electronic parts may contain brominated flame retardants. It has not been possible to identify any uses, but according to the information obtained the capacitors do not contain BFRs.

It will roughly be estimated that the total content of BFRs in switches and other parts of lighting sold in Denmark in 1997 was below 4 tonnes.

Production

Lighting is produced in Denmark by several manufacturers. The BFR containing semi-manufactures for the production is mainly imported, and there is a limited knowledge regarding BFRs in the products.

Consumption

The total consumption of brominated flame retardants with lighting in Denmark 1997 is estimated at 4-14 as shown in table 2.10.

Table 2.10
Consumption of brominated flame retardants with lighting parts in Denmark 1997

Trend in consumption

In Danish production of lighting there has been a trend of substitution BFRs for other flame retardants in plastic cover parts.

Emission during use

Emission during use is discussed in section 1.4. The brominated flame retardants are predominantly used as additives. In lighting the plastic parts, especially sockets, heat up during operation and the emission may be significant.

Recycling and waste disposal

Plastic parts of lighting is ultimately disposed of to landfills or incineration. Waste disposal of lighting is included in section 3.2. The consumption of BFRs with lighting is estimated to be stagnant and the amount disposed of is roughly estimated to equal the current consumption.

2.2.5  Wiring and Power Distribution

To comply with the fire safety standards most plastic parts of wiring in houses and within other power distribution systems contain flame retardants or are based on polymers, notably PVC, with inherent flame retardancy.

Brominated flame retardants are used as well as chlorinated, phosphorus and inorganic flame retardants.

The main applications of brominated flame retardants are:

Sockets, mounting boxes and other components used for wiring in houses often contain brominated flame retardants. According to information from a major Danish producer 10-30% of all plastic parts will contain brominated flame retardants. Traditionally PBDEs have been used for these applications, but in products on the Danish market only TBBPA (in PET) and HBCD (in PS) have not been identified. PBDEs and other BFRs may be present in some imported products.

Both brominated and chlorinated flame retardants are used in rubber for insulation of flame retardant flexible cables. The main use of rubber insulated cables are temporary wiring at construction sites, but wiring of windmills also account for a significant volume. The cables have to comply with fire safety standards, be flexible and resistant to high mechanical wear.

Information on the flame retardants in rubber has been received for products from three major producers. Two producers were using PBBs and PBDE, one was using chlorinated compounds. Halogen-free products are available for smaller wires.

The brominated flame retardants are used in the rubber at loadings of about 6-7%. Based on rough estimates from a large foreign producer of cables containing PBBs and PBDEs, the total Danish consumption of each compound would be of the magnitude of 30 tonnes, if all rubber cables contained brominated flame retardants. They surely do not. From the producer in question only one third of the rubber cables contained brominated flame retardants, and chlorine containing cables have presumably a significant market share. There are, however, many companies represented on the Danish market, and an analysis of the whole market has not been possible.

On basis of the present information the total consumption of brominated flame retardants with rubber cables in Denmark in 1997 is roughly estimated at 1-5 tonnes PBDEs and 1-5 tonnes PBB.

In fire-resistant wires used for fire alarms, emergency lighting and other applications in which there are especially strict fire safety requirements, flame retardancy is usually obtained by layers of silicon compounds and glass woven fabric.

Brominated flame retardants may be used for other cables. Cable insulation is the major application for flame retarded polyethylene in W. Europe (cf. table 1.6). About 3,500 tonnes BFRs are used with PE in W. Europe, but it is not clear whether BFRs are actually used for cable insulation.

It has not been possible to identify any cables (except rubber cables) with brominated flame retardants on the Danish market, but as cables are imported from many countries it cannot be ruled out.

Contactors, relays, switch gear, starters, etc. used for power distribution and industrial automation are in general made from flame retarded PA, PC and PBT/PET. BFRs are the main flame retardants for these applications.

There is no Danish production of this equipment and it has been difficult to obtain specific information. The equipment is imported from many European countries and the group cover a wide range of different equipment. The Danish market for this equipment is of about the same value as the market for wiring parts.

As discussed in section 2.2.3 the W. European market volume for PET/PBT, PC and PA was about 12,500 tonnes in 1998. A significant part of this is estimated to be used for power distribution and industrial automation.

The total consumption of flame retarded plastics used for production of ''Electrical equipment material" in W. Europe was 35,000 tonnes in 1995 of which 54% were flame retarded with BFRs (see table 1.7). The group includes circuit breakers, switches, etc., but not internal parts of appliances and machines. If it is assumed that the plastics contain about 15% BFR the amount can be translated into about 3,000 tonnes.

Considering the available information it will roughly be estimated that 10-25 tonnes BFRs was used for these applications in Denmark in 1997.

Technical laminates based on for instance polyester, epoxy or phenolics in V-0 grades are used for a wide range of applications in electric equipment: bobbins, switchboard panels and partition walls, transformer insulation, etc. TBBPA is known to be used for technical laminates for these applications, but other flame retardants, for instance tetrabromophthalic anhydride, may be used as well. Most technical laminates used for transportation do not contain BFRs, but the fire safety requirements to the laminates used for electric equipment are stricter. The laminates are typically used for switchboard panels and similar applications and will be included in the estimates for contactors, relays, etc.

According to the literature BFRs may be used in capacitors. It has not been possible to identify BFR containing capacitors.

Consumption 

The total consumption of brominated flame retardants with equipment for wiring and power distribution in Denmark 1997 is estimated at 30-80 as shown in table 2.11.

Table 2.11
Consumption of brominated flame retardants with products for wiring and power distribution in Denmark 1997

Trend in consumption

In Denmark and Germany there has been a trend of substituting halogen-free flame retardants for BFRs in polyamides. For the other polymers the trend has been a replacement of PBDEs by TBBPA and other brominated flame retardants and an increase in the consumption due to a general increase in the consumption of EE equipment.

There is a wide range of cables marketed as halogen-free and a pronounced trend away from halogen-containing flame retardants. Of the equipment for power distribution and industrial automation it has only been possible to identify a contactor marketed as halogen-free. The other equipment is estimated to contain one or more BFR containing parts.

Emission during production

Emission to air and waste water during production is treated jointly for all production processes in section 1.4 and 3.4.

Emission during use

Emission during use is discussed in section 1.4. The brominated flame retardants are mostly used as an additives. Emission from this equipment may be of significance.

Recycling and waste disposal

Other plastic parts of EE equipment is ultimately disposed of to landfills or incineration. Recycling of electronics is discussed in detail in section 3.1.1 and waste disposal in section 3.2. The plastic containing flame retardants are not recycled.

Substitution

Substitution of BFRs in plastics for this equipment is discussed in section 7.4.2 and 7.4.3.

2.2.6  Textiles

Based on international experience, the following types of applications of brominated flame retardants in textiles are possible:

Textiles and furniture used in transportation are covered below in section 2.2.9, but the used materials will in broad outline not be different.

Flame retardants are one of the major categories of chemicals used in textiles. Comprehensive reports dealing with textiles and the chemicals used in textiles have been issued by the Swedish National Chemicals Inspectorate and the Danish Environmental Protections Agency in 1997 /40,41/. The first report discusses the chemicals used for textiles, and the latter focuses on the life cycle of the base textiles. The Swedish report inform that perhaps only 10-20% of the textiles sold in Sweden are Swedish-made, and that for apparels (clothes) the percentage may be only half.

These two reports do not give detailed information on brominated flame retardants used for textiles, which reflects a low or negligible use of these chemicals in the respective domestic textile industries and textile after treating industries.

However, the relatively high share of imported textiles, after-treating made abroad and imported textile-containing products (mainly furniture), means that the use of BFRs for textiles used in Denmark cannot be ruled out.

The dominating flame retardant system for textiles based on bromine is hexabromocyclododecane (HBCD) and decabromodiphenyl ether (DeBDE) in conjunction with antimony trioxide /9,42/. Both DeBDE and HBCD are additive substances.

The use of brominated flame retardants for textiles within the EU, takes place mainly in the United Kingdom and Ireland, where there are strict requirements of flame retardancy treatment of upholstered furniture.

Protective clothing

No use of brominated flame retardants has been identified for civil purposes. In the past though it has been normal to use e.g. the bromine-antimony system for some types of protective clothing. The disadvantage of the bromine based flame retardant systems for clothing, is the lack of softness of the treated product.

The only known use of BFRs in textiles for clothing in Denmark is connected to ABC uniforms from 1984 (ABC: atomic, biologic, chemical), produced for the Danish Army. The used mixture consists of the antimony/decabromodiphenyl ether system in combination with inorganic phosphorus compounds. The ABC uniforms are designed to be worn for maximum 30 days and to stand one wash at 30°C. When a uniform has been used (e.g. in war zones), the clothing is used for training purposes in Denmark and through repeated laundering, most impregnation will be washed out. On the basis on information from the Danish Army round 4 tonnes decabromodiphenyl ether will be present in the stockpile.

Children's night-dress 

Within the UK and the USA, requirements regarding the flammability of children's night-dresses exist, and night-dresses fulfilling these requirements are also found on the Danish market. According to major producers of flame retardants for textiles, the use of organophosphates is absolutely dominant, and possibly no brominated compounds are used. The only possible use might occur in 100% polyester products, in which BRF represents a cheap solution, meeting the requirements.

Tents

Internationally, tents are one of the major textile end-products for brominated flame retardants. They are used for both military tents and civil tents especially 'party' tents. Apparently there are no such consumption in Denmark. According to the Danish military other solutions than bromine antimony systems are used, but some import of flame retarded tents may take place. The possible consumption is assumed to be low, most probably under 1 tonnes.

Carpets

No use of brominated flame retardants in Denmark has been identified. Demands regarding flame retardancy exist only within the contract market. The contract market is defined as products purchased to public or private institutions, business, e.g. for offices, industry, canteens, hospitals, and kindergartens. The absolutely predominant flame retardancy system is based on aluminium hydroxide combined with various fillers, incorporated in the back side layer.

DeBDE might to some extent be used for synthetic carpets, but it is unlikely that these products reach the Danish market in significant amounts, whereas existing requirements for flame retardancy are reached by cheaper alternatives. Still industry information and /3/ indicate that PBDEs or other BFRs might be present in flame retarded carpets based on cheaper synthetic fibres, where they are encapsulated within the polymer fibres.

Curtains

Flame retarded curtains are not normally used in Denmark. It is in textiles based on plastic that brominated flame retardants are most likely to be found, and the most likely products are blackout curtains, roller blinds and cinema screens. Bromine/antimony systems with PBDEs or HBCD are likely to be used. No actual consumption has been identified, but a small consumption is likely to occur.

Upholstered furniture

In Denmark, furniture used for the contract market are normally flame retarded. The flame retardant may be added to both the textile and the padding.

Among the main Danish textile finishers supplying the furniture industry, the general statement is that no brominated flame retardants are used.

The main entries to the Danish market of furniture with textile treated with brominated flame retardants are furniture for the 'contract market'. A normal practise among some suppliers of contract furniture is to sell products produced for the English civil market, as these fulfil the requirements stipulated by the British Standard, that are regarded as some of the most rigorous rules for fire protection of furniture.

Foam and stuffing for upholstered furniture

Seemingly, no Danish producer of various types of foam for furniture, cars, etc., uses brominated flame retardants. Chlorinated organophosphates (e.g. TCPP) and melamine are normally used for slap stock foam, but it must be expected that foreign produced foams may contain brominated flame retardants. The bromine analogue to TCPP has had a widespread use. Other used systems might be phosphorus derivatives used with penta-bromodiphenyl ether.

The expanded polystyrene stuffing in sack chairs, health mattresses, nurse cushions, etc., is normally flame retarded with between 0.5% and 1% hexabromocyclododecane. This may correspond to a yearly consumption of HBCD between 200 and 700 kg.

Production in Denmark

Seemingly no application of brominated flame retardants for textiles takes place in Denmark. This information is based on inquiries among the Danish industries and major foreign suppliers of brominated flame retardants for textiles.

Inquiries among Danish producers of slap-stock foams indicate that no brominated flame retardants are used in Danish production of foams.

Import/export

The main supply of brominated textiles to the Danish market is through import of furniture or textile for furniture. A major part of the upholstered furniture, produced for export to the UK, is made with textiles treated or produced in the UK. The major part of the import of flame retarded textiles is possibly exported as furniture, partly for the UK market, partly for the contract market.

Consumption in Denmark

The major Danish consumption of BFRs within the category "textiles" is related to furniture.

BFRs might be present in imported special curtains and related textile products made on plastic basis and in imported carpets made from synthetic fibres. No cases have been identified though.

The total consumption of brominated flame retardants with textiles in 1997 is estimated at 2-11 tonnes as shown in table 2.12.

Table 2.12
Consumption of brominated flame retardants with textiles in Denmark 1997

Trends in consumption

The future trends in consumption are very dependent on the specific fire regulations. At the level of the EU, negotiations on this issue are underway. These will be of essential importance to the future consumption of flame retardants for textiles, and may have consequences for the choice between different technical solutions (i.e. the use of brominated flame retardants).

Seemingly, aromatic BFRs are substituted by aliphatic BFRs (e.g. HBCD). Furthermore the general tendency is that BFRs are being substituted by halogen-free alternatives, including inherently flame retardant textiles.

Emissions during use

It is expected that emission to waste water from washing of furniture textiles in offices, etc., will be negligible.

It is assumed that the emission from textiles that are washed regularly will lead to emissions to waste water. This is relevant to protective clothing. It is assumed that on average half of the flame retardants will be washed out, before the products are discarded. Furthermore the consumption of protective clothing with BFRs for civil purposes has formerly been larger.

Hence the emission to waste water is expected to be <150 kg BFRs per year. Correspondingly it is expected that 150 kg BRF are disposed of with solid waste.

On average, round 50 kg DeBDE is likely to be released per year to the waste water from ABC uniforms through the washing processes (the used uniforms are put to training use, and are washed repeatedly in this connection).

Waste disposal

It assumed that a volume corresponding to the consumption are disposed of with solid waste.

2.2.7   Building Materials

Within the building industry, brominated flame retardants are used in some specific synthetic materials. The main categories are

Insulation   

Insulating boards and sheets for buildings that potentially contain brominated flame retardants can be made of:

Insulation, EPS & XPS 

EPS and XPS are at large used for comparable purposes. Still, XPS is more durable and more expensive than EPS, and this does influence the actual application of the two materials. In Europe, both materials are normally flame retarded with hexabromocyclododecane (HBCD). In EPS between 0,5% and 1% is used, and in XPS between 1% and 2% is used.

The plain insulation panels have a wide use in construction. They are used for insulation of foundation, ground deck, parking deck, compact (flat) roof, roof terrace and roof gardens. They are furthermore used for soil insulation in connection with frost vulnerable constructions such as railways, road, other traffic areas, sport centres, water pipes and waste pipes.

Insulation panels made of EPS and XPS may be worked up and sheathed with various materials for special insulation panels for e.g. the construction industry and for transportation. This processing is called 'fabrication'.

In general, XPS materials used in Denmark are flame retarded today whereas EPS materials used in Denmark are only flame retarded when this is in explicit demand.

Due to the strict requirements regarding the flammability of building materials in Denmark, the plastic based insulation is normally only allowed when it is encapsulated in non-combustible and approved materials, and hence no flame retardants are required for the foam. The major exception from this is flat roof constructions on factory buildings where less strict requirements exist, and local fire authorities sometimes grant dispensation. This permits the use of typically EPS as an alternative to mineral wool. Considering information from suppliers it is estimated that as a maximum, five percent of the EPS used in construction in Denmark are flame retarded. This corresponds to 0.5 to 2.7 tonnes HBCD per year in EPS insulation.

The use of flame retarded XPS in construction in Denmark is possible only explained by the fact that all XPS are produced abroad, in countries where the fire regulations allow the use of flame retarded foams for insulation of buildings.

Furthermore, industry contacts explain the foreign use of flame retarded EPS and XPS panels for road construction and building with the fire risk during the construction phase. Fire risks may for instance be possible fire-raising at road constructions or sparks from welding on construction sites.

Insulation, PUR

Flame retarded rigid polyurethane is used for a number of different insulation purposes within construction. PUR is a thermoset plastic made through the reaction of an isocyanate and a polyol. PUR may be flame retarded with both additive and reactive brominated flame retardants. The dominant flame retardants for polyurethanes are brominated polyols, that is reactive flame retardant. If requirements are strict, other additives and reactives may be combined with the brominated polyol.

The predominant use of flame retarded rigid polyurethanes is with construction.

PUR foam has very good insulation characteristics and is widely used within the building sector for cold-storage plants, freezing rooms and cold stores, e.g. at supermarkets, processing rooms in the food industry, and refrigerating holds at ships and in containers. Minor consumption areas are façade insulation, pre-insulated pipes, and joint filler foam.

In general these applications are always flame retarded, except the last three where the use of flame retardants depends on the actual application.

In a number of applications flame retardants, and hence also BFRs, are not used. These are home-refrigerators, plain district heating pipes (some indoor uses e.g. in factories may imply the use of BFRs).

PE pipe-insulation

Heat pipes and hot water pipes may be insulated with flexible self-extinguishing foam-tubes, made of PE foam. According to professionals, this PE pipe insulation is only used occasionally by smaller entrepreneurs and private persons for home-made installations in smaller dwelling houses, whereas professional entrepreneurs in Denmark almost solely choose mineral wool. PE foams may be flame retarded with HBCD, but also PBDEs may be used. Round 4-500 km PE tubes og 75-100 gram per meter is expected to correspond to 0.5 to 2.5 tonnes used per year.

Foils

Foils may be made of polyolefins (PE, PP, etc.) or PVC. For most applications, the PVC product does not contain any flame retardants. The polyolefins may be flame retarded with chlorinated and brominated paraffins, with PBDEs and other additive flame retardants, such as ethylene bis(tetra-bromo-phthal-imide), brominated polystyrene and TBBPA derivatives.

Foils are used for three main purposes:

In Denmark, only the first category is normally flame retarded due to formal regulation. Round 20% of the flat roofs in Denmark are roofed with alternatives to roofing felt. The major part - approximately 90% - of the roofing foils are made of PVC. Of the remaining part approximately 80 tonnes polyolefins are flame retarded with brominated flame retardants, corresponding to 1-4 tonnes brominated flame retardants, depending on the base polymer.

Foils used for damp proofing under roof and in walls would normally not be flame retarded in Denmark due to price competition.

Foils used for civil engineering are normally not affected by fire regulations, but according to industry information, up to 10-20% is possibly flame retarded.

Outer panels

Internationally, flame retarded panels are used for construction. Epoxy based TBBPA in glass fibre reinforced panels for construction and translucent panels with a combination of halogenated FR and phosphorus chemicals for building roofing are examples /11/, but Danish applications have not been identified. Small amounts of these types of building materials may be used in Denmark.

Other uses

Other materials than those mentioned above might be flame retarded, but have not been assessed. These might be wall linings, e.g. based on glass fibre with a flame retarded binder, special grips, handles, etc.

Also through-going installations between premises must be flame retarded. Hence it is known that PBDEs may be used for the outer coating of some through-going water pipes, and that some ventilating shafts also may be flame retarded. Today the self extinguishing polyphenylenesulfide polymer is often used for the latter purpose, and the consumption of BFRs for this purpose is most probably negligible.

Wooden panels may be impregnated with ammonium bromide to obtain a building material that passes the test as a class 1 covering material. Ammonium bromide does, however, fall outside the present definition of BFRs, while ammonium bromide is an inorganic substance.

Production in Denmark

All the substances used for the different productions - if any - are imported. This is e.g. polystyrene granulate for expanded polystyrene, polyolefins and isocyanates for polyurethanes, polyethylene for foils.

The domestic supply of EPS panels is almost solely produced in Denmark, and flame retarded panels are seldom requested. The production for export is mainly based on processed panels, and on flame retarded panels.

There is no production of XPS in Denmark.

An extensive production of polyurethane panels exists in Denmark. On the basis of information from the industry, it is estimated that 50-70% of the Danish production of expanded PUR is exported, and that the import covers round 20% of the home market. Import are mainly directed at smaller refrigerated rooms. The total supply to the Danish market corresponds to round 50% percent of the production, which is 80-120 tonnes. Hence the consumption corresponds to round 40-60 tonnes per year

No production of PE pipe insulation exists in Denmark.

Flame retarded foils are produced in Denmark, for both roofing and as damp courses. Both types of products are mainly exported, and the latter is apparently solely produced for export.

Consumption in Denmark

The total consumption of XPS insulation in Denmark amounts to round 35,000-45,000 m3. Of this it is assumed that 80% are flame retarded, and hence the consumption related to XPS corresponds to 11-29 tonnes HBCD.

The total consumption of brominated flame retardants with building materials in 1997 is estimated at 50-100 tonnes (see table 2.13).

Table 2.13
Consumption of brominated flame retardants with building materials in Denmark 1997

Trends in consumption

In general, the consumption within the building and construction sector is stable.

Waste generation during use

Generally, when a tender is given, the waste generation at the construction site is taken to be 10% /43 /. In practice, the average waste generation is expected to be lower, depending on the material and the application.

Based on information from the line of business it is estimated that 2-5% of the used EPS and XPS is cut off during mounting and disposed of with combustible building waste.

The loss during use is depending on the application. According to suppliers, the loss is normally low and here estimated to be 2% of the used volume.

For PE pipe insulation, foils and panels the waste generation during use is assumed on average to correspond to 5% of the used volume.

2.2.8   Paints and Fillers

Brominated flame retardants may be used in:

Paints   

As to flame retardancy paints can be divided into two groups:

Intumescent paints

There are two market segments of intumescent paints: Steel constructions in buildings and industry and off-shore constructions and ships.

When heated, intumescent paints are designed to swell (intumesce) into a thick, insulating char that protects the underlying material from fire by providing a physical barrier to heat and mass transfer. The paints are typically based on epoxy polymers and do not contain BFRs. The retardancy effect is obtained by the combination of a carbon source, a catalyst (e.g. ammonium polyphosphates), and a blowing agent (e.g. melamine). There is no production of intumescent paints in Denmark.

PBDEs may be used for marine and industry paints /7/. Marine paints used in Denmark are imported directly by the customer from abroad and no specific information on these paints have been available.

"Low flame spread" paints

"Low flame spread" paints are used for cabins and engine rooms on ships. According to Danish producers of paints, these paints do not contain BFRs.

Joint fillers

Flame retardant joint fillers may contain brominated flame retardants. According to information from the line of business, flame retardant joint fillers will most often be of the intumescent type and contain nitrogen and phosphorus flame retardants.

An exception is joint filler foam of PUR that is included in section 2.2.7.

Fire proofing of wood

Flame retarded wood panels are used as an alternative to cement based panels in construction where there are requirements. As well brominated as other flame retardants are used for fireproofing of wood.

Consumption 

Brominated flame retardants are not classified dangerous, and there are no requirements on registering of the compounds in the Danish Product Register. However, if they are constituent parts of products containing dangerous substances, information on the flame retardants will be included in the record of the product. Paint, fillers and wood impregnation will usually contain classified substances and thus be registered.

According to the Danish Product Register 0.3 tonnes decabromodiphenyl ether (DeBDE) is annually used with paints. Empirically the registered quantities may be higher than the actual consumption and represent the consumption pattern some years ago. By the Product Register it has been confirmed that the products are still in use, but the information on the application areas is confidential. The use of brominated flame retardants in paints has not been identified in this survey, but it is assumed to be used for ships or construction works.

The registered consumption of brominated flame retardants with fillers and similar products was negligible, and it is estimated that the consumption with filler, etc. in 1997 was <0.2 tonne.

The registered consumption of brominated flame retardants with wood impregnation is considered confidential, but it is estimated that 0.5-1.2 tonnes other brominated flame retardants was used for this application in 1997.

In total 0.6-1.7 tonnes brominated flame retardants were used for these applications in Denmark 1997 (see table 2.14).

Table 2.14
Consumption of brominated flame retardants with paint, wood impregnation and fillers in Denmark 1997