The air pollutants ammonia, non-methane volatile organic compounds, nitrogen oxides, fine particulate matter and sulphur oxides damage the environment and human health. Reducing their anthropogenic emissions is a priority for European Union and international air quality legislation. Since 2005, emissions of all five pollutants have declined with sulphur oxide reducing the most (84%) and ammonia the least (17%). Stronger effort, particularly in the agriculture, transport and energy sectors, is essential for the EU to fulfil longer term reduction commitments.
Figure 1. Emission trends of the main air pollutants in EU-27 between 2005 and 2023, presented as a percentage of their level in 2005
The NECD sets legally binding EU Member State specific percentage reduction commitments for these five main air pollutants. The reduction commitments are defined as reductions compared with 2005 levels and are applicable for the years 2020-2029. The reduction commitments are more ambitious from 2030 onwards.
Under the NECD, all EU Member States must report annual emissions inventories for the five air pollutants. Between 2005 and 2023, emissions of four of these pollutants declined considerably in the Member States: SOx emissions by 84%, NOx by 53%, NMVOCs by 35% and PM2.5 by 38%. Emission reductions from the energy, industry and transport sectors are largely responsible for these declines. This is partly a result of sector-specific emission limit values set by other EU legislation, such as the Industrial Emissions Directive and Euro standards for vehicles.
NH3 emissions also declined, but only by 17% overall. This reflects limited progress in the agriculture sector, which is responsible for more than 94% of NH3emissions in the EU.
Figure 2. Changes in the main air pollutant emissions by EU Member State in 2023 compared to 2005 levels
Between 2005 and 2023, all Member States reduced their emissions of NMVOCs, NOx, SOx and PM2.5, while NH3 emissions increased in Bulgaria and Latvia. Despite the reductions, several countries are not on track to meet their reduction commitments for 2020-2029, with NH3 as the main challenge.
Almost all Member States need to reduce their emissions of at least one pollutant to reach the more stringent 2030 commitments, as presented in an EEA briefing on the status of reporting under the NECD. The main hurdle will be to reduce NH3 emissions, for which only 12 Member States have already met their 2030 emission reduction commitments in 2023. Furthermore, reducing NOx and PM2.5 emissions will be a challenge for several Member States.
More effective policies and measures, particularly in the agriculture, transport and energy sectors, are essential for Member States to meet their emission reduction commitments. They are also required to meet the European Green Deal and Zero Pollution Action Plan targets to reduce air pollution to levels .
Supporting information
This indicator tracks trends in anthropogenic emissions of the five main air pollutants — NOx, NH3, SOx, NMVOCs and PM2.5 — since 2005. All of these pollutants, directly or indirectly, have negative effects on human health, vegetation or ecosystems.
This indicator supports the assessment of progress towards meeting the national emission reduction commitments under the Gothenburg Protocol under the UNECE Air Convention and the National Emission reduction Commitments Directive. The human health and environmental objectives defined in the NECD, the Gothenburg Protocol and the are addressed by other EEA indicators.
Recommended methodologies for emission inventory estimation are included in the EMEP/EEA air pollutant emission inventory guidebook. The original EU Member State submissions are available from the EEA Data Service. For the collated EU dataset, where necessary, gaps in reported data are filled by the EEA (see "Methodology for gap-filling" below). The final gap-filled data used in this indicator are available from the EEA DataHub.
The gap-filling methodology enables a complete time-series trend to be compiled despite gaps in the data reported by a Member State. It applies a stepwise approach using emission data from other reporting obligations to fill gaps in the national data sets, followed by further gap-filling procedures such as interpolation or extrapolation and manual changes. For the pollutants for which a country did not report emissions for any year, gap-filling cannot be performed. For these pollutants, therefore, the aggregated data for the EU are not complete and are likely to underestimate true emissions. Further methodological details of the gap-filling procedure are provided in the European Union emission inventory report 1990-2023 under the UNECE Convention on Long-range Transboundary Air Pollution (Air Convention).
Effects of air pollution:
Anthropogenic emissions of these air pollutants contribute to poor air quality in Europe. This can lead to to adverse effects on human health, vegetation and ecosystems. Some examples of effects are listed below:
PM can be emitted directly into the air (primary PM) or it can be formed in the atmosphere (secondary PM) from airborne precursor substances (NOx, NH3, SOx). Both primary and secondary PM have negative health effects.
Ground-level ozone (O3) is created from precursor substances (NO2, NMVOCs, CH4 and CO) in the atmosphere via photo-chemical reactions and contributes to the formation of secondary PM. Ground-level ozone has negative effects not only on human health, but also on crops and ecosystems.
In addition, excess deposition of sulphur and nitrogen compounds also lead to disturbances in the functioning and structure of ecosystems, i.e. by causing acidification of soils and waters, and, in the case of nitrogen, eutrophication in nutrient-poor ecosystems such as grasslands.
Internationally, the was the first step towards addressing the impacts of air pollution on health and the environment. A centrepiece of this convention is the 1999 Gothenburg Protocol to Abate Acidification, Eutrophication and Ground-level Ozone. In 2012, the Protocol was amended to introduce national emission reduction commitments for 2020 and beyond for SOx, NOx, NH3 and NMVOCs. The revised Protocol was also the first binding agreement to include emission reduction commitments for PM2.5. It also introduced and updated emission limit values for key stationary and mobile sources in several technical annexes. Furthermore, the protocol established the critical loads concept as a tool for informing political discussions related to damage to sensitive ecosystems. Critical ground-level ozone concentrations for vegetation were also defined.
The National Emission reduction Commitments Directive:
The National Emission reduction Commitments Directive (NECD) outlines obligations to reduce national emissions of the five main air pollutants: SOx, NOx, NH3, NMVOCs and PM2.5. The current reduction obligations apply from 2020 to 2029, while stricter obligations will apply from 2030 onwards.The national emission reduction commitments for 2020 to 2029 were transposed from the Gothenburg Protocol.
The 1999 Gothenburg Protocol was followed in 2001 by the EU’s NECD, which was repealed by the in 2016. The original directive introduced legally binding national emission limits for four main air pollutants: SOx, NOx, NH3 and NMVOCs. The directive required that EU Member States had met emission ceilings by 2010 or in the years thereafter, up to the end of 2019, and established emission reduction commitments for 2020-2029 and 2030 onwards for the five main pollutants. The goal of this legislation was to enable the EU to comply with the amended Gothenburg Protocol by 2020, followed by enabling more ambitious emission reductions from 2030 onwards.
EU Environment action programmes:
Environment action programmes (EAP) have led the development of EU environment policy since the early 1970s. In 2020, the Commission adopted a proposal for a decision on a general , to continue from the 8th EAP.
Ambient Air Quality Directive:
As part of the Zero Pollution ambition, the EU has revised the Ambient Air Quality Directive, to align air quality standards more closely with the recommendations of the World Health Organization. Directive (EU) 2024/2881 on ambient air quality and cleaner air for Europe amends and recasts Directive 2008/50/EC on ambient air quality and Directive 2004/107/EC concerning heavy metals and polycyclic aromatic hydrocarbons in ambient air.
The revised directive on ambient air quality sets out air quality provisions with the aim of achieving a zero-pollution objective, so that air quality within the Union is progressively improved to levels no longer considered harmful to human health, natural ecosystems and biodiversity.
The revised directive lays down limit values, target values and other air quality standards. In the case of non-compliance with the air quality limit or target values established in EU legislation, air quality plans or roadmaps must be developed by Member States and implemented in the air quality areas in which exceedances occur or may occur. These plans and roadmaps should aim to bring concentrations of air pollutants to levels below the relevant air quality standard. To ensure overall coherence, and consistency between different policies, air quality plans and roadmaps should be consistent (if feasible) and integrated with plans and programmes in line with the directives regulating air pollutant emissions.
Methodological uncertainty:
The use of a gap-filling methodology for countries that have not reported emissions for one or more years can potentially lead to artificial trends, but it is considered unavoidable for obtaining a comprehensive and comparable set of emissions data for European countries for policy analysis purposes.
Data sets uncertainty:
are thought to have an uncertainty of about ± 20%, as NOx is emitted from both fuel burnt and the combustion of air, so emissions cannot be estimated accurately from fuel nitrogen alone. However, because of the need for interpolation to account for missing data, the complete data set used will have a higher degree of uncertainty. The overall trend is likely to be more accurate than individual absolute annual values — the annual values are not independent of each other.
Overall scoring — 1-3; 1 = no major problems, 3 = major reservations:
relevancy: 1;
accuracy: 2;
comparability over time: 2;
comparability over space: 2.
SOx emission estimates in Europe are thought to have an uncertainty of about ± 10%, as the sulphur comes from only the fuel burnt; therefore, emissions of SOX can be more accurately estimated than emissions of NOx. However, because of the need for interpolation to account for missing data, the complete data set used will have a higher degree of uncertainty. . From these studies, differences in the annual averages have been estimated to be ± 30%, which is consistent with an inventory uncertainty of ± 10% (there are also uncertainties in the measurements and especially in the modelling). The trend is likely to be much more accurate than individual absolute values.
Overall scoring — 1-3; 1 = no major problems, 3 = major reservations:
relevancy: 1;
accuracy: 2;
comparability over time: 2;
comparability over space: 2.
NH3 emission estimates in Europe are more uncertain than those for NOX, SOX and NMVOCs, largely because of the diverse nature of major agricultural sources. It is estimated that they have an uncertainty of around ± 30%. The overall trend is likely to be more accurate than the individual absolute annual values — the annual values are not independent of each other.
Overall scoring — 1-3; 1 = no major problems, 3 = major reservations:
relevancy: 1;
accuracy: 2;
comparability over time: 2;
comparability over space: 2.
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.
Policy-effectiveness indicator (Type D)SDG15: Life on land
The changes in emissions over time of each main pollutant are given as percentages (%).
Once a year
References and footnotes
<div class="csl-bib-body" style="line-height: 1.35; ">
<div class="csl-entry">EC, 2013, Communication from the Commission to the European Parliament, the Council, the European Economic and Social Committee and the Committee of the Regions — ‘A clean air programme for Europe’, COM(2013) 918 final.</div>
</div>
<div class="csl-bib-body" style="line-height: 1.35; ">
<div class="csl-entry">EU, 2016, Directive (EU) 2016/2284 of the European Parliament and of the Council of 14 December 2016 on the reduction of national emissions of certain atmospheric pollutants, amending Directive 2003/35/EC and repealing Directive 2001/81/EC, OJ L 344, 17.12.2016, p. 1–31.</div>
</div>
<div class="csl-bib-body" style="line-height: 1.35; ">
<div class="csl-entry">EU, 2008, Directive 2008/50/EC of the European Parliament and of the Council of 21 May 2008 on ambient air quality and cleaner air for Europe</div>
</div>
<div class="csl-bib-body" style="line-height: 1.35; ">
<div class="csl-entry">EC, 2020, Proposal for a decision of the European Parliament and of the Council on a General Union Environment Action Programme to 2030, COM(2020) 652 final.</div>
</div>
<div class="csl-bib-body" style="line-height: 1.35; ">
<div class="csl-entry">Norwegian Meteorological Institute, 2010, <i>Transboundary, acidification, eutrophication and ground level ozone in Europe in 2008</i>, EMEP Status Report, 1/2010, European Monitoring and Evaluation Programme.</div>
</div>
