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From Clean Air in London:
This App reports the health impact of long-term exposure to dangerous airborne particles (PM2.5) for the population in local areas, regions and England as a whole. The App estimates the number of deaths attributable to air pollution on a pro rata, calendar year-to-date, basis and the time to the next attributable death as well as displaying the percentage of total deaths attributable to air pollution. It does not estimate or display the number of actual deaths from air pollution or the risk for an individual. Users can also see estimates for total population-weighted exposure to annual average concentrations of PM2.5 in different local areas and/or regions relative to World Health Organisation guidelines and England as a whole