Air pollution causes more than 480,000 premature deaths across Europe each year despite “slowly” improving air quality on the continent, the EU’s environment authority said.

Data collected at monitoring stations showed that 82 percent of the EU’s urban population was exposed to these microscopic particulates, known as PM2.5, in 2015, down from 85 percent in 2013.

Other sources of air pollution linked to the premature deaths include nitrogen dioxide, emitted in the air, and ground-level ozone caused by motor vehicle emissions.

Within the 28 European Union members, fine particulates were responsible for more than three out of four premature deaths (399,000 out of 487,600) in 2014.