Road transport remains the single main source of a number of harmful pollutants, according to a recent report from the European Environment Agency.

Vehicles remain the largest source of nitrogen oxides (NOx), carbon monoxide (CO) and non-methane volatile organic compounds (NMVOCs), and the second-most important source of fine particulate emissions (PM10 and PM2.5) in the EU-27. Most EU-27 countries have reduced their emissions of air pollutants in recent decades. But pollution continues to undermine local air quality, particularly in urban areas.

The report shows that road transport, energy production, manufacturing industries and construction, the residential sector and agriculture are the main sources of air pollution in Europe today.

Across the EU-27 the largest reduction in emissions has been achieved for the acidifying pollutant SOx: emissions in 2006 were almost 70 per cent less than in 1990. Emissions of other key air pollutants also fell during this period, including emissions of the three air pollutants primarily responsible for the formation of harmful ground-level ozone in the atmosphere: CO (53 per cent reduction), NMVOCs (44 per cent reduction) and NOx (35 per cent reduction).

Despite the 35 per cent drop in NOx emissions since 1990, the change in total NOx emissions between 2005 and 2006 was just 1.8 per cent, and in the main resulted from reductions in Germany, Italy and the United Kingdom.

NOx are one of the main contributors to the formation of ground-level ozone, high levels of which can trigger severe respiratory problems. It also makes an important contribution to acidification and eutrophication. Electricity and heat production are the main source of sulphur oxides (SOx) emissions (58.4 per cent), followed by manufacturing industries and construction sources (14.3 per cent). SOx is an acidifying pollutant, which can also aggravate respiratory diseases.

Agriculture is responsible for the vast majority of ammonia (NH3) emissions in EU-27. NH3 is an important pollutant, which causes acidification and eutrophication. Livestock manure, together with emissions associated with fertilisers account for more than 90 per cent of NH3 generation.

The European Community ratified the United Nations Economic Commission for Europe's Convention on Long-range Transboundary Air Pollution (UNECE LRTAP Convention) in 1982. The Convention has set up a process for negotiating concrete measures to control specific pollutants through legally binding protocols. Since 1984, eight protocols have come into force. A complete set of emission inventory data for the main air pollutants is still not available from Member States. Member States could do more to ensure full and timely data are available. A number of Member States are also forecast to miss 2010 emissions targets as laid down in Community legislation.

1. Source: EEA Technical report No 7/2008. (2008). 'Annual European Community LRTAP Convention emission inventory report 1990-2006 Submission to EMEP through the Executive Secretary of the UNECE'.