A health impact study has for the first time estimated the mortality burden attributable to air pollution in more than 1,000 European cities. The study, published in The Lancet Planetary Health, includes a ranking of the European cities with the highest rates of mortality attributable to each of the two air pollutants studied: fine particulate matter (PM2.5) and nitrogen dioxide (NO2). The research project was led by the Barcelona Institute for Global Health (ISGlobal), in collaboration with researchers from the Swiss Tropical and Public Health Institute (Swiss TPH) and Utrecht University.