The quality of air in the United Kingdom is currently better than at any point since before the industrial revolution. However, atmospheric pollution is currently estimated to reduce the life expectancy of every person in the UK by an average of 6 months with estimated equivalent health costs of up to £19 billion a year. This is in addition to wider environmental damage including change in species composition, change in ecosystem function and decreased agricultural yields.

We need to undertake further research into how air pollution impacts health and the environment to inform future policy decisions. In the long term, understanding the interplay between air pollution and climate change could provide large mutual benefits.

Particulate matter (PM10)

The objective that by the end of 2004 the 24 hour mean should not exceed 50 µg/m³ more than 35 times a year was not met at six sites. The objective that by 2004 the annual mean should not exceed 40 µg/m³ was exceeded only at London Marylebone Road. 

PM₁₀ annual mean: Comparison with health objective for 2004: 1992-2008 Urban Sites

 PM₁₀ fixed 14 hour mean: Number of days exceeding 50µg/m³ compared with health objective for 2004: Urban sites 1992-2008

More information can be found in Defra’s particulate statistics

Annual mean background PM₁₀ concentration, 2008 (µg m^-3, gravimetric)

Map from EIONET Central Data Repository

Nitrogen dioxide (NO₂)

The figures below show trends in exceedences at urban sites of the objective levels for the 1-hour and health-based annual mean respectively. There were 6 sites where hourly concentrations reached 'moderate' levels in 2006. None of the sites exceeded the EC Alert Threshold on any one day.

Nitrogen Dioxide 1 hour mean: Number of periods exceeding 200µg/m³ compared with health objective for 2005: Urban Sites 1987-2008.

Nitrogen Dioxide annual mean: Comparison with health objective for 2005: 1987-2008, µg/m³

More information can be found in Defra’s nitrogen dioxide statistics.

Urban major urban roads, annual mean roadside NO₂ concentration, 2008, µg m^-3

Map from EIONET Central Data Repository

Tropospheric Ozone

There has been a marked increase in ozone concentrations in urban areas since the 1990s, due to the reduction in urban emissions of nitrogen oxides (NO_X), which destroy ozone close to their emission source. Rural ozone levels averaged 71 µg m^-3 in 2008 compared to 74 µg m^-3 in 2006 and 68 µg m^-3 in 1993. There is no clear long term trend.

From year to year there can be significant variations caused by the weather.

Annual levels of ozone 1987-2008: index shows annual mean of the daily maximum 8-hour running mean.

Further information can be found at particulate/ozone statistics.

Number of days with ozone concentration > 120 µg m^-3 in 2008

Acidification and Eutrophication

Currently, 54 per cent of all habitat areas sensitive to acidification exceed the critical load for acidity, predominantly due to the deposition of nitrates.

Despite reductions in ammonia emissions, total N-deposition has changed little. Currently, 58 per cent of all habitat areas sensitive to eutrophication from N-deposition exceed the critical load for nutrient nitrogen.

Human Health impacts

Air pollution is currently estimated to reduce life expectancy by an average of 6 months with estimated equivalent health costs of up to £19 billion a year. There is currently an underestimation of the full range of possible health benefits that could be attained from policy measures to improve air quality, because it has not been possible to quantify all health outcomes. Work to review the evidence is ongoing and it is expected that this would lead to an increase in the number of health outcomes identified.

Population

The overall population of the UK is estimated to be almost 61.8 million in 2009, up from 55.6 million in 1970 and 57.2 million in 1990. 62 per cent of the population is assumed to be of working age. For more information see population statistics.

UK population by gender and age, 2009

Economic growth

Between 1990 and 2008, GDP grew in real terms by 55 per cent. For more information see GDP statistics.

Energy demand

Since 1999, indigenous energy production has fallen from being 22 per cent above consumption to 21 per cent less than consumption. For more information see Energy statistics.

Transport

Road traffic in Great Britain has grown by 85 per cent between 1980 and 2009 from 277 to 514 billion vehicle kilometres, as demonstrated in the Department for Transport report Transport Trends 2009.

Key Pressures:

Information regarding pressures relating to the drivers displayed above is held in the National Atmospheric Emissions Inventory.

Sulphur dioxide (SO₂) 

Since 1970, there has been a substantial overall reduction of more than 92 per cent in SO₂ emissions to 512kT.

Ammonia (NH₃) 

Emissions in 2008 represent a decrease of 23 per cent on the 1990 emissions, to 281kT. The most significant cause of reductions in recent years has been decreasing cattle numbers in the UK.

Nitrogen oxides (NO_X)

Since 1970, overall NO_X emissions have decreased by 53 per cent to 1403 kT, mainly as a result of a 58 per cent decrease from road transport.

Non-methane volatile organic compounds (NMVOCs)

NMVOC emissions in 2008 were well below the 2010 ceiling at 942 kT.

Methane (CH₄)

Since 1970, the total methane emission in the UK has declined by 51 per cent to 2312 kT.

Particulate matter (PM₁₀)

Emissions of PM₁₀ have declined by 73 per cent since 1970, to 133 kT.

Particulate matter (PM_2.5)

Emissions of PM_2.5 have declined greatly, to 81kT in 2008.

The table below demonstrates change over time in UK emissions of atmospheric pollutants covered by the National Emission Ceilings Directive (NECD), including predictions for 2010. The UK is currently predicted to exceed the 2010 NO_X ceiling, with compliance expected by 2012.

Emissions of air pollutants under the National Emission Ceilings Directive (NECD), UK, 1970 – 2008, kilotonnes.

Further emissions reductions are expected for all pollutants, with the exception of NH₃ for which little decrease in emissions is expected beyond 2010 based on ‘business as usual’ projections.

The Critical Load Exceedance for acidification is predicted to decrease to 40 % of habitat areas by 2020 in the absence of further measures. The Critical Load Exceedance for eutrophication due to nutrient nitrogen is expected to decrease to 48 % of habitat areas by 2020.

The UK’s main policies and measures for achieving National Emissions Ceilings and ambient air quality limit values are set out in the revised Air Quality Strategy for England, Scotland, Wales and Northern Ireland, published in July 2007. Responsibility for implementing these measures rests with Defra and the devolved Governments of Scotland, Wales and Northern Ireland (the Devolved Administrations). 

The UK is currently on course to meet its NECD 2010 emission ceilings for SO₂, VOCs and NH₃.  However, like many other European countries, the UK is currently projected to exceed its 2010 NO_X ceiling by a small percentage with compliance expected by 2012. The situation is being closely monitored with a view to meeting the ceiling as soon as possible.

UK legislative controls on emissions to air from industrial installations have been vital to improving air quality locally, nationally and internationally. Large industrial installations (some 4,500 in the UK) are subject to integrated pollution prevention and control (IPPC) which requires limit values (ELVs) to be set on the basis of best available techniques for all likely significant emissions. This approach is also used in regulating air emissions for some 20,000 smaller industrial installations.

Both national and local government consider air quality issues when developing transport interventions. Current key national transport measures to improve air quality include: