London Health Burden of Current Air Pollution and Future Health Benefits of Mayoral Air Quality Policies

A project quantifying the health impact of NO2 and PM2.5 in London


Transport for London (TfL) and the Greater London Authority (GLA) commissioned researchers from the Environment Research Group (ERG) at Imperial College London to assess the impact on health of the mayoral air quality policies, and air pollution in London, using current (2019) and future levels of air pollution up to 2050 (projected from 2013).

Key Findings

  • In 2019, in Greater London, the equivalent of between 3,600 to 4,100 deaths (61,800 to 70,200 life years lost ) were estimated to be attributable to human-made PM2.5 and NO2, considering that health effects exist even at very low levels. This calculation is for deaths from all causes including respiratory, lung cancer and cardiovascular deaths.
  • With the adoption of the Mayor’s air quality policies and taking into account general air pollution trends, the average life expectancy of a child born in London in 2013 would improve by around 5 to 6 months.
  • Without the Mayor’s air quality policies and other general air pollution trends, a child born in 2013 would lose 7 to 11 months life expectancy due to air pollution.
  • The mortality burden in 2019 was affected by a number of factors (population size, pollution, deprivation, age of population (as baseline mortality increases with age)):
    • The greatest burden, as a proportion of the population, falls in Outer London boroughs, even though pollution levels there are relatively lower, mainly due to the higher proportion of the elderly in these areas.
    • Conversely, Inner London boroughs had a lower burden of air pollution related mortality due to their younger age profile. However, for other air quality related health outcomes such as asthma admissions in children, boroughs with younger populations will be more affected.
  • The team also found that London’s population would gain around 6.1 million life years if air pollution concentrations improved, per the Mayor’s air quality policies scenario, from 2013 to 2050, following up the population exposed for a lifetime up to 105 years after 2050 (2154 ). This gain was in comparison to pollution levels remaining at 2013 concentrations.
  • The gain in life expectancy from the projected future air pollution changes is less influenced by population size than the gain in life years. The life expectancy gains were larger in Inner London, including some more deprived boroughs, probably due to the greater concentration reductions in Inner London and to variations in baseline mortality rates.
  • If London is enabled to meet the WHO guideline for PM2.5 by 2030, the population in London would gain a 20% increase in life years saved over the next 20 years.
  • The report does not cover effects on illness, such as hospital admissions and asthma exacerbations that are also affected by air pollution.


Dr David Dajnak
Dimitris Evangelopoulos
Nutthida Kitwiroon
Sean Beevers
Heather Walton


Go to the Full Paper

© Imperial College London, Environmental Research Group. All rights reserved 2020.