A3: Concentrations of fine particulate matter (PM2.5) in the air

Final Final

Short description

This indicator is a measure of the level of long-term exposure of people to harmful airborne fine particulate matter (PM2.5). Long-term exposure to particulate matter contributes to the risk of developing cardiovascular disease and lung cancer. The main sources of PM2.5 pollution are industrial processes, combustion in residential, public, commercial and agricultural sectors and road transport.

This indicator is an assessment of clean air (reporting the condition of the atmosphere as an asset). It can also be considered as pressure on human health. It is determined by calculating the annual population-weighted mean concentration of PM2.5 in the air, assessed as background concentrations per 1 km square. The population-weighted mean concentration is used as a measure of the impact of PM2.5 on the health of the total population. Greater weighting is given to concentrations of PM2.5 in urban areas to reflect the higher population density as those concentrations will affect a greater number of people. In addition, people living in urban areas are generally exposed to greater levels of PM2.5 than those living in rural areas.

Data are already published annually at UK Air Information Resource, Modelled background pollution data.


PM2.5 annual mean concentrations are estimated annually for every square kilometre of the UK through the Pollution Climate Mapping (PCM) model. The geographical distribution of the UK population is then joined to the estimated concentrations to estimate the annual mean concentration of PM2.5, weighted on where the population lives. This enables us to account for the majority of the population living in densely populated urban areas, where concentrations are likely to be greatest.

Trend description

Population-weighted annual mean concentrations of fine particulate matter (PM2.5) in England have declined from 12.1 ug/m3 in 2011 to 9.6 ug/m3 in 2019, a fall of 21% over the latest 8 years for which data are available.


Choose categories from the dropdowns below to see different breakdowns of the data. Some will not be available until a higher level is chosen.

This table provides metadata for the interim or final indicator presented above.

Indicator name

Concentrations of fine particulate matter (PM2.5) in the air

Indicator reference


Outcome Indicator Framework theme


Headline indicator status

Air quality

Relevant goal(s) in the 25 Year Environment Plan
  • Clean air
Relevant target(s) in the 25 Year Environment Plan
  • Meeting legally binding targets to reduce emissions of five damaging air pollutants
Position in the natural capital framework
  • Condition of assets - atmosphere
Related reporting commitments
  • None
Geographic scope

England; also available at local authority level.

Status of indicator development


Date last updated

11 June 2021