Air quality: policies, proposals and concerns

Poor air quality is considered by the government to be “the largest environmental risk to public health in the UK”. As well as human health, air pollution also has implications for the natural environment and for the economy. Due to the transboundary (cross-border) nature of air pollution, action to manage and improve air quality in the UK has been driven by international agreements and EU legislation, as well as by national and devolved legislation.

This briefing gives an overview of the current outdoor air quality legal framework, governance and enforcement mechanisms, forthcoming changes, and ongoing issues and concerns.

Information about road user charging schemes intended to reduce air pollution is set out in a separate Commons Library briefing, Clean Air Zones, Low Emission Zones and the London ULEZ.

For information about indoor air quality, see the Parliamentary Office of Science and Technology (POST) briefing, Indoor Air Quality.

Sources of air pollution

Poor air quality arises from a range of pollutants, including sulphur dioxide; nitrogen oxides (NOx); particulate matter; ozone; non-methane volatile organic compounds; heavy metals; polycyclic aromatic hydrocarbons; benzene; 1,3-butadiene; carbon monoxide; and ammonia. These pollutants come from natural and human-made sources such as fossil fuel combustion, road transport, industrial processes, waste incineration, domestic heating, agriculture, solvents and chemical reactions in the atmosphere.

Reasons for concern about air pollution

Air pollution is a major concern because it can harm human health, and contribute to respiratory and cardiovascular disease, cancer, asthma, impaired lung development and premature mortality. Air pollution can also disproportionately affect deprived communities. It damages the natural environment by affecting soils, rivers, lakes, crops, ecosystems and biodiversity, and it has economic impacts through healthcare costs, lost productivity and reduced economic growth.

Current UK air pollution laws

UK air quality legislation is a mesh of international commitments, assimilated EU law and domestic legislation.

Gothenburg Protocol

At the international level, the Gothenburg Protocol and amendments to it set emissions ceiling levels for various pollutants. The protocol’s aim is to control long-range transboundary pollution. The UK is a signatory to the protocol.

Domestic regulations

The Gothenburg Protocol’s main requirements have been implemented in the UK by the National Emission Ceilings Regulations 2018.

The UK also has rules on ambient air quality (the air that more immediately surrounds us) which are set out in the Air Quality Standards Regulations 2010. Instead of setting a ceiling for pollutants, it sets “limit values” (parameters that must not be exceeded) for concentrations of different pollutants.

The UK Government has two further targets to reduce fine particulate matter (PM2.5) in England by 2040, set by The Environmental Targets (Fine Particulate Matter) (England) Regulations 2023.

UK air quality plans and policies

In the UK, air quality limit values are devolved to the administrations in Scotland, Wales and Northern Ireland. The Secretary of State for Environment, Food and Rural Affairs is responsible for meeting the limit values in England, and the Department for Environment, Food and Rural Affairs (Defra) coordinates assessment and air quality plans for the UK as a whole.

At a national level, the UK Government and the devolved executives are required to produce a national air quality strategy. In 2007, Defra and the devolved executives published the Air Quality Strategy for England, Scotland, Wales and Northern Ireland. In April 2023, the UK Government published the Air quality strategy: framework for local authority delivery, which superseded the 2007 strategy in England only. In August 2020, the Welsh Government replaced the 2007 strategy with its Clean Air Plan for Wales: Healthy Air, Healthy Wales.

The UK Government and each of the devolved executives can also choose to publish their own air quality policies. Notable examples include:

• UK Government: Clean Air Strategy 2019, January 2019 and Environmental Improvement Plan 2025, December 2025.
• Scottish Government: Cleaner Air for Scotland 2, July 2021. A Cleaner Air for Scotland 2 strategy: progress report, was published in June 2025 to track progress against the strategy. The progress report says that a new air quality framework is expected to be published in 2026.
• Welsh Government: Clean Air Plan for Wales: Healthy Air, Healthy Wales, August 2020, and Update Report on Progress Against Actions, April 2023.
• Department of Agriculture, Environment and Rural Affairs: Clean Air Strategy for Northern Ireland: A Public Discussion Document, November 2020.

Long-term trends in emissions

From 1990 to 2024, estimated UK emissions of four out of five important pollutants fell by more than two thirds (as shown in the chart below). The only important pollutant in which there wasn’t a drop in emissions was ammonia (NH3). The largest reduction was in sulphur dioxide (SO2), which fell by 97% from 1990 to 2024. The fall in emissions of non-methane volatile organic compounds (NMVOCs) and fine particulate matter (PM2.5) slowed noticeably in the last decade.

Source: Defra, Emissions of air pollutants, 12 February 2026

Governance and enforcement bodies

Since the UK left the EU, its environmental law and policy (including on air quality), which was derived from EU law and policy, is no longer subject to the oversight of EU institutions. As environmental matters are generally devolved, each part of the UK has subsequently put in place new governance arrangements for environmental matters, including on air quality:

• In England and Northern Ireland, the Office for Environmental Protection, has been established.
• In Scotland, Environmental Standards Scotland has been established.
• In Wales, the Environment (Principles, Governance and Biodiversity Targets) (Wales) Act 2026 will allow the Welsh Government to establish the Office of Environmental Governance Wales (OEGW). The Welsh Government has two years from Royal Assent (27 April 2026) to establish the OGEW as a legal entity, although this period can be extended up to a maximum of 48 months from Royal Assent, subject to regulations being passed by the Senedd Cymru/Welsh Parliament.

Future UK policy changes

In December 2025, the UK Government published a revised Environmental Improvement Plan and an accompanying Air quality Environment Act target delivery plan. These documents set out that in 2026 the government plans to:

• explore options to reduce emissions from small industrial combustion plants (generally, boilers and generators with a thermal input of below 1 megawatt thermal (MWth))
• consult on new measures to reduce emissions from domestic combustion

In January 2026, the government and devolved administrations published a consultation on reducing emissions from solid fuel burning. Changes have not yet been made and the government says that it is analysing feedback. For further information, see the Commons Library briefing Controls on domestic wood-burning and solid fuel use in England (March 2026).

EU air quality changes

In November 2019, the European Commission published a Fitness Check of the Ambient Air Quality Directives. It concluded that these directives have been partially effective in improving air quality, but not fully effective, and that not all objectives have been met. Subsequently, a revised directive (Directive (EU) 2024/2881 of the European Parliament and of the Council of 23 October 2024 on ambient air quality and cleaner air for Europe) now sets limit values to be attained by member states by 1 January 2030.

Health concerns

Air quality has long been a high-profile issue, with specific concerns around human health. This was highlighted in the Chief Medical Officer’s annual report 2022: air pollution, which was published in December 2022. Academic research has found big differences in air pollution across communities, with deprived areas often the worst affected. Children, elderly people and people with pre-existing cardiovascular and respiratory conditions are particularly vulnerable to the effects of poor air quality. In 2020, a coroner found that air pollution was a significant contributory factor to the death of a nine-year-old child in London.