Air Pollution: Meeting Nitrogen Dioxide Targets

The Government’s latest Air Quality Plan for tackling nitrogen dioxide (NO₂) published in July 2017 acknowledged poor air quality as the largest environmental risk to public health in the UK. The Royal College of Physicians estimates that the annual cost of health problems resulting from exposure to air pollution in the UK exceeds £20 billion. This includes costs to society and business, health services and individuals who are affected. In addition, the potential adverse health impacts from exposure to particulate matter and nitrogen dioxide, beyond the fairly well understood impacts on cardiovascular and respiratory disease, are the subject of much attention and ongoing research.

Meeting air quality targets

Under EU legislation, Member States must meet air quality targets for a range of pollutants. A deadline for reducing NO₂ levels was extendable from 2010 to 2015, as long as an adequate air quality plan to reduce emissions was in place. However, several countries, including the UK, have failed to meet this deadline. Currently a number of areas in the UK do not meet the NO₂ targets, especially roadsides in urban centres.

The UK’s continuing failure to meet air quality targets has led to ClientEarth taking the Government to court successfully several times since 2014 over the lack of an effective plan to reduce NO₂ levels. A further court case was launched in November 2017. These, combined with the Dieselgate scandal, when it became clear that many diesel cars where not meeting legal emissions limits under real driving conditions, has raised awareness of the impacts of air pollution on health. The UK is also subject to EU infraction proceedings for failure to meet NO₂ targets.

The UK is obliged under international treaties to reduce overall emission of certain pollutants, but local air quality targets are contained in EU legislation. The Government has stated its commitment to maintaining air quality targets after Brexit.

Reducing transport emissions

A range of measures have been proposed at a local and national level to address the link between emissions from transport, diesel emissions in particular, and NO₂ pollution. The Government published Air quality plan for nitrogen dioxide (NO₂) in UK (2017) on 26 July 2017. This included a range of proposals focused on action in local areas where emissions are highest, including an extension of earlier proposals for clean air zones.

In addition, there has been a focus on more stringent emissions controls and live testing for vehicles; extending existing emissions zones where worse emitting vehicles are excluded; and a diesel scrappage scheme and support for Ultra Low Emission Vehicles.

Further reading

This brief primarily covers the UK efforts to address NO₂ pollution.  For details of individual air pollutants, their sources and impacts see POST note on Ambient Air Quality. Defra’s UK Informative Inventory Report (1990 to 2015) published in March 2017, provides data on UK pollutant emissions and the Air Quality Plan 2017 provides more detailed information on NO₂ sources.