Indicator Assessment

Persistent organic pollutant emissions

Indicator Assessment
Prod-ID: IND-170-en
  Also known as: AIR 002
Published 04 Sep 2019 Last modified 02 Dec 2021
13 min read
  • Since 1990, emissions of persistent organic pollutants (POPs) decreased in the EEA-33 countries, e.g. hexachlorobenzene (HCB) decreased by 95 %, polychlorinated biphenyls (PCBs) by 75 %, dioxins and furans by around 70 % and polycyclic aromatic hydrocarbons (PAHs) by 83 %.
  • The majority of countries report that POP emissions fell during the period 1990 to 2017.
  • In 2017, the most significant sources of emissions included the ‘Commercial, institutional and households’  and ‘Industrial processes and product use’ sectors.

Change in emissions of persistant organic pollutants

Data sources:
Data sources:

In the EEA-33 region, emissions of polycyclic aromatic hydrocarbons (PAHs) decreased by 77 % between 1990 and 2017 (Figure 1). A combination of targeted legislation, details of which are set out in the 'Indicator specification — policy context' section, coupled with improved controls and abatement techniques, has led, in general, to significant progress being made in most countries to reduce PAH emissions (Figure 3).

Although the majority of individual countries report that PAH emissions have decreased since 1990, five countries (Bulgaria, Denmark, Finland, Malta and Romania) have reported an increase in PAH emissions. One cause of these increased emissions is the introduction of policy measures that have encouraged the burning of renewable materials (e.g. wood by Danish households). Wood burning produces emissions of PAHs and hence, in this instance, policies that have been implemented to address one environmental issue (climate change) have had unintended consequences on another (air pollution). In absolute terms, the emissions of PAHs from these countries are relatively low compared with other countries, but the effect on local populations and environmental quality may, nevertheless, be notable. Of the EEA-33 countries, Portugal and Germany reported the highest PAH emissions.

Emissions of hexachlorobenzene (HCB) have fallen sharply in the EEA-33 since 1990, mostly because of a decrease of 4.3 tonnes in HCB emissions in the United Kingdom between 1998 and 1999, which accounts for 98 % of the decrease in EEA-33 emissions since 1999 (Figure 2). This was due to the introduction of regulations in the United Kingdom to control the use of hexachloroethane (HCE) tablets as a degassing agent in secondary aluminium production.

Emissions of polychlorinated biphenyls (PCBs) in the EEA-33 decreased by 83 % between 1990 and 2017, mainly because of reductions in 'Industrial processes and product use' emissions, which accounted for 87 % of the decrease over this period (Figure 3). Within the EEA-33 region, four countries (Cyprus, the Netherlands, Spain and Sweden) reported emissions of PCBs in 2017 that were higher than emissions in 1990;  Greece, Iceland and Malta reported a 'questionable' increase in PCB emissions (Figure 2). In 2017, 23 countries reported lower emissions than in 1990 and the remaining three countries either did not report data or reported zero emissions for 1990.

The reported emissions of dioxins and furans in the EEA-33 countries decreased by about 70 % between 1990 and 2017. Of the 32 countries that reported non-zero emissions, only Greece, Liechtenstein and Romania reported an increase in emissions between 1990 and 2017 (Figure 2). In 2017, 32 % of dioxin and furan emissions were from sources in the 'Waste' sector, 25 % were from the 'Commercial, institutional and households' sector and 22 % were from the 'Energy production and distribution' sector (Figure 3).

Emissions of selected persistent organic pollutants by sector


Important sources of emissions of persistent organic pollutants (POPs) typically include residential combustion processes (open fires, coal and wood burning for heating purposes, etc.), industrial metal production processes and the road transport sector.

Commercial, institutional and households: Current emissions from ‘Commercial, institutional and households’ sources account for about 45 % of total PAH emissions and a quarter of the total dioxin and furan emissions in the EEA-33. Emissions from households have declined since 1990 as a result of a decrease in the residential use of coal.

Industrial processes and product use: While industrial processes and product use sources account for more than two thirds of PCB emissions in the EEA-33, emissions from this sector have decreased by around 83 % since 1990. Reductions in POP emissions in the 'Industrial processes and product use' sector result from improvements in abatement technologies for metal refining and smelting.

Road transport: Road transport emissions do not make particularly large contributions to total POP emissions in the EEA-33.

Supporting information

Indicator definition

  • This indicator tracks trends in anthropogenic emissions of POPs since 1990. At the moment, emissions of PAHs are described, but emissions of other POP compounds will be added in the future.
  • The indicator also provides information on emissions by sector: Energy production and distribution; Energy use in industry; Industrial processes; Road transport; Non-road transport; Commercial, institutional and households; Solvent and product use; Agriculture; Waste; and Other.
  • Geographically, the indicator covers the EEA-33. The EEA-33 country grouping includes countries of the EU-28 (Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden and the United Kingdom), European Free Trade Association (EFTA) countries (Iceland, Liechtenstein, Norway and Switzerland) and Turkey.
  • Temporally, the indicator covers the same time coverage of the last version of the LRTAP Report.


The units used in this indicator are the tonne (metric ton).


Policy context and targets

Context description

Targeted European Commission legislation (directives and regulations), coupled with improved control and abatement techniques, have led to good progress being made by the EEA-33 countries towards reducing air emissions of POPs, including the PAH group of chemicals. Such legislation is described below.

  • The ultimate objective of the 1998 UNECE Aarhus Protocol on POPs (to the 1979 Convention on Long-range Transboundary Air Pollution (LRTAP)) is to eliminate any discharges, emissions and losses of POPs. The original protocol bans the production and use of some products outright (aldrin, chlordane, chlordecone, dieldrin, endrin, hexabromobiphenyl, mirex and toxaphene), while others are scheduled for elimination at a later date (DDT, heptachlor, hexachlorobenzene and PCBs). In 2009, the protocol was updated to list commercial pentabromodiphenyl (Penta-BDE) and commercial octabromodiphenyl (Octa-BDE) as POP substances, and the POPs task force concluded that hexabromocyclododecane (HBCD) also met the criteria to be considered a POP, and therefore potential risk management options are currently being considered for it. Finally, the protocol severely restricts the use of DDT, hexachlorocyclohexane (HCH), including lindane, and PCBs, and includes provisions for dealing with the wastes of products that will be banned. It also obliges parties to reduce their emissions of dioxins, furans, PAHs and HCB to below their 1990 levels (or an alternative year between 1985 and 1995). It also lays down specific limit values for the incineration of municipal, hazardous and medical waste.
  • The 2001 UNEP Stockholm Convention on POPs aims to reduce and ultimately cease the manufacture, use, storage and emission of POPs, as well as to destroy existing stocks. It provides for measures to reduce or eliminate emissions resulting from intentional and unintentional production and use. It also plans to meet the obligations on technical and financial assistance for developing countries and countries with economies in transition, and to cooperate and exchange information. Twelve POPs were covered under the original scope of the Stockholm Convention:
    • pesticides: aldrin, chlordane, DDT, dieldrin, endrin, heptachlor, hexachlorobenzene, mirex and toxaphene;
    • industrial chemicals: HCB and PCBs;
    • by-products: HCB; polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/PCDF), and PCBs.

 In May 2009, additional chemicals were added to the Stockholm Convention:

    • pesticides: chlordecone, alpha hexachlorocyclohexane, beta hexachlorocyclohexane, lindane and pentachlorobenzene;
    • industrial chemicals: hexabromobiphenyl, hexabromodiphenyl ether and heptabromodiphenyl ether, pentachlorobenzene, perfluorooctane sulfonic acid, its salts and perfluorooctane sulfonyl fluoride, tetrabromodiphenyl ether and pentabromodiphenyl ether;
    • by-products: alpha-HCH, beta-HCH and pentachlorobenzene.

The EC Communication on a Community Strategy for Dioxins, Furans and PCBs (COM (2001) 593 final) aims to assess the current state of the environment and to reduce human exposure and long-term environmental effects. This communication does not propose legislative measures, but could be the basis for a Community action plan.

The Directive on the Limitation of Emissions of Certain Pollutants into the Air from Large Combustion Plants (2001/80/EC) has had the effect of reducing heavy metal and PAH emissions via dust control and absorption.

Regulation (EC) No 850/2004 on Persistent Organic Pollutants entered into force on 20 May 2004. The main purpose of this regulation is to enable the European Community to ratify the Stockholm Convention and the Aarhus Protocol. The regulation also deals with stockpiles of redundant substances.

Emissions of a number of heavy metals released from certain industrial facilities are also estimated and reported under the requirements of the European Pollutant Release and Transfer Register Regulation (E-PRTR) (166/2006/EC).

The EU Directive on Ambient Air Quality and Cleaner Air for Europe (2008/50/EC) and Directive 2004/107/EC relating to heavy metals and polycyclic aromatic hydrocarbons in ambient air contain provisions, and target and limit values for the further control of air pollutants in ambient air.

There are also a number of specific EU environmental quality and emission standards for heavy metals and POPs in coastal and inland waters, drinking waters, etc. These have only indirect relevance to air emissions as they do not directly specify emission or precipitation quality requirements, but rather specify the required quality of receiving waters. Such measures include Directive 84/491/EEC on HCH discharges; Directives 76/464/EC and 86/280/EC on dangerous substances; and the Water Framework Directive (2000/60/EC).


As noted above, the Aarhus Protocol on POPs to the UNECE LRTAP Convention obliges parties to reduce their emissions of dioxins, furans, PAHs and HCB to below their 1990 levels (or an alternative year between 1985 and 1995 inclusive).

Related policy documents



Methodology for indicator calculation

This indicator is based on the national total and sectoral emissions officially reported to the EEA and UNECE/EMEP (United Nations Economic Commission for Europe/Co-operative programme for monitoring and evaluation of the long-range transmission of air pollutants in Europe) LRTAP Convention. For the EU-28 Member States, the data used are consistent with the emissions data reported by the EU in its annual submission to the LRTAP Convention.

Recommended methodologies for emission inventory estimation are compiled in the EMEP/EEA Air Pollutant Emission Inventory Guidebook (EMEP/EEA, 2016). Base data are available from the EEA Data Service and the EMEP web site. If necessary, gaps in reported data are filled by the European Topic Centre for Air and Climate Change using simple interpolation techniques (see below). The final gap-filled data used in this indicator are available from the EEA Data Service .

Indicator specification and metadata

Base data, reported in the UNECE/EMEP nomenclature for reporting (NFR14) sector format, are aggregated into the following EEA sector codes to obtain a consistent reporting format across all countries and pollutants:

  • Energy production and distribution: emissions from public heat and electricity generation, oil refining, production of solid fuels, extraction and distribution of solid fossil fuels and geothermal energy;
  • Energy use in industry: emissions from combustion processes used in the manufacturing industry including boilers, gas turbines and stationary engines;
  • Industrial processes: emissions derived from non-combustion-related processes such as the production of minerals, chemicals and metals;
  • Road transport: light and heavy duty vehicles, passenger cars and motorcycles;
  • Non-road transport: railways, domestic shipping, certain aircraft movements and non-road mobile machinery used in agriculture and forestry;
  • Commercial, institutional and households: emissions principally occurring from fuel combustion in the services and household sectors;
  • Solvent and product use: non-combustion-related emissions mainly in the services and households sectors including activities such as paint application, dry-cleaning and other use of solvents;
  • Agriculture: manure management, fertiliser application and field-burning of agricultural wastes;
  • Waste: incineration and waste water management;
  • Other: emissions included in national totals for the entire territory that are not allocated to any other sector.


The following table shows the conversion of NFR sector codes used for reporting by countries into EEA sector codes:

EEA classification

Non-greenhouse gases (GHGs) (NFR)

National totals

National total

Energy production and distribution

1A1, 1A3e, 1B

Energy use in industry


Road transport


Non-road transport (non-road mobile machinery)

1A3 (excl. 1A3b)

Industrial processes and product use








Commercial, institutional and households

1A4ai, 1A4aii, 1A4bi, 1A4bii, 1A4ci, 1A4cii 1A5a, 1A5b




Methodology for gap filling

An improved gap-filling methodology was implemented in 2010 that enables a complete time-series trend for the main air pollutants (nitrogen oxides (NOx), sulphur oxides (SOx), non-methane volatile organic compounds (NMVOCs), ammonia (NH3) and carbon monoxide (CO)) to be compiled. In cases in which countries did not report emissions for any year, it meant that gap filling could not be applied. For these pollutants, therefore, the aggregated data are not yet complete and are likely to underestimate true emissions. Further methodological details of the gap-filling procedure are provided in section 'Data gaps and gap-filling' of the European Union emission inventory report 1990–2017 under the UNECE Convention on Long-range Transboundary Air Pollution (LRTAP).

Methodology references



Methodology uncertainty

The use of gap filling for countries that have not reported emissions for one of more years can potentially lead to artificial trends, but it is considered unavoidable if a comprehensive and comparable set of emission data for European countries is required for policy analysis purposes.

Data sets uncertainty

Uncertainties in the emission estimates of PAHs reported by countries are considered to be higher than for other more 'traditional' air pollutants, such as NOx and SO2, because of the relatively high uncertainties that exist with regard to both activity data and emission factors for this group of pollutants. Emission estimates for the other POPs are also considered to have a high degree of uncertainty.

Rationale uncertainty

This indicator is regularly updated by the EEA and is used in state of the environment assessments. The uncertainties related to methodology and data sets are therefore important. Any uncertainties involved in the calculation and the data sets must be accurately communicated in the assessment, in order to prevent erroneous messages from influencing policy actions or processes.

Data sources

Other info

DPSIR: Pressure
Typology: Performance indicator (Type B - Does it matter?)
Indicator codes
  • AIR 002
Frequency of updates
Updates are scheduled once per year
EEA Contact Info


Geographic coverage

Temporal coverage