Breathe London Data Report - 2021-22

The first Breathe London data report has revealed that every sensor in the network recorded pollution levels that exceeded global guidelines in 2021 and 2022, underlining the importance of ongoing efforts to clean up London’s air. The full report can be found here:  Network Reports — Breathe London.

The Breathe London Network, established in 2021 as a partnership between the Mayor of London, Imperial College London, and Bloomberg Philanthropies, is making reliable air quality monitoring data more accessible to local communities by building a network of accurate and reliable air quality sensors across the capital.

Having grown rapidly from 136 initial sites to over 400 locations in just two years, its sensors have been installed in priority locations in partnership with local schools, hospitals, boroughs, cultural institutions, and community groups. These groups can choose where they locate the air quality sensors, empowering citizens with evidence to manage their exposure to air pollution and campaign for cleaner air.

The new report revealed that levels of nitrogen dioxide (NO2) and fine particulate matter (PM2.5) decreased at 16 sites and 21 sites, respectively, among the locations with sufficient data available for both years. The largest reductions were recorded in Greenwich, where one site recorded a 20 per cent reduction in NO2, and in Tower Hamlets, where a site recorded a 33 per cent reduction in PM2.5.

Despite this progress, every Breathe London monitoring site across the capital with sufficient data capture recorded levels of NO2 and PM2.5 that exceeded the World Health Organization’s (WHO) air quality guidelines in both 2021 and 2022, including all school and hospital sites. Pollution levels also exceeded the UK’s less strict legal PM2.5 annual air quality objective (to be met by 2040) at 195 sites and the NO2 annual air quality objective at nine sites—not only in inner London, but also in outer boroughs such as Brent, Croydon, Harrow, Merton, and Sutton.

Local communities play a vital role in the Breathe London Network. As part of the Breathe London Community Programme, 60 community groups have received free sensors to monitor and tackle local air pollution through support from the Mayor of London and Bloomberg Philanthropies. Participating groups receive support from Imperial’s Environmental Research Group with analysing the data, empowering them with the information they need to advocate for cleaner air. Data from all the sensors in the Network is available in near real-time, for all Londoners to see, free on the Breathe London website.

If you would like to learn more about Breathe London and the Breathe London Community Programme then please email us on: breathelondon@imperial.ac.uk.