The fine dust world

Fine dust particles are contained in airborne particulate matter, invisible to the naked eye. These microscopically small particles are on average 10 μm in diameter (micrometer, PM10), and cannot be intercepted by mucous membrane in nose or throat due to their tiny size so that they can enter the body unhindered through lungs and bloodstream.

Fine dust pollution varies according to season and weather conditions, statutory limit values are, however, regularly exceeded.  Air pollution is highest in highly populated areas and cities that lie in basins. Automobile clubs and health organizations regularly call for additional traffic-related measures, such as improving public transport for commuters or requiring fine particle stickers for older trucks.

Three causes are held responsible for the massive increase in fine dust: Traffic, industry and domestic heating. Fine particles exist in diesel exhaust particulates, tire particles or emissions from industrial plants, power stations and heating systems. On the road, exhaust fumes from diesel vehicles without particle filters are the main culprit but vehicles equipped with direct fuel injection also emit fine dust particles. 

90 percent of city population affected

The European Environment Agency measured fine dust particles for their report on air quality in Europe - with drastic results:  According to the study, 90% of all city residents are exposed to high levels of pollution.  Taking the limit values of World Health Organization WHO into account (which are not binding), close to 88 percent of city residents live in areas where the  PM10 level of particle contamination is too high. Taking contamination levels of PM2, 5 into account, the figure increases to 96 percent.