Air pollution with Particulate Matter (PM) causes serious environmental and especially health problems. According to the World Health Organization airborne particles have the potential to cause severe health risks as e.g. cardiorespiratory diseases and a shortening of life expectancy. PM differ with respect to their chemical components and their sizes. PM10 (aerodynamic diameter up to 10 mm) is able to infiltrate the bronchial tubes; PM 2.5 (aerodynamic diameter up to 2.5 10 mm) – the ‘respirable’ fraction of PM - is able to enter the lung and the pulmonary alveoli. In densely populated cities and city regions much more persons are affected by high PM10 and PM2.5 concentrations than in rural areas. Particulate matter has both natural and anthropogenic sources. In cities and city regions anthropogenic sources like power plants, domestic fuel, and especially traffic cause a large proportion of the PM load. Maximum PM loads occur in and beside roads with high traffic density. The increase of traffic is one component of global change, not only in Europe, but even more in the fast growing urban agglomerations of the developing countries. During the last decades, PM loads have been subject to scientific and political debate and to reduction measures. According to the European Directive on ambient air quality and cleaner air for Europe from 2008, emissions of PM10 and PM2.5 shall be reduced in order to improve human health conditions especially in densely populated areas. Regular measurements have to be carried out in zones and agglomerations where the longterm objectives for air pollutants including PM are exceeded. Many cities prepared or renewed clean air plans and installed ‘environmental zones’ where individual traffic is or will be restricted according to the emission rates of the respective vehicle. The variability of PM exposure within one city may result in different health risks within different urban districts and residential areas. In an interdisciplinary study we investigated the spatial correlation between PM10 concentrations and the social structure in the city of Berlin, Germany. We found out that (1) the highest PM10-loads occur within the environmental zone, i.e. in the area enclosed by the circle line of the rapid transit system. Hot spots were the districts of Friedrichshain-Kreuzberg, Tempelhof-Schöneberg, and Neukölln. Taking into consideration the population figures within the environmental zone, about 75% of the inhabitants of the environmental zone, and thus more than 20 % of the population of Berlin are exposed to high PM10-loads. (2) By overlaying the PM10- loads with social status and dynamic data of the people living within the environmental zone, we determined that a large share of population within the environmental zone is disadvantaged twice: especially socially deprived people - that are considered vulnerable groups - are endangered by high to very high PM10-concentrations. As a consequence, the hypothesis stated at the beginning of our investigation could be verified: areas with a (very) low social status – respectively with a high share of socially vulnerable groups - concurrently show (very) high PM10-loads. These results show that environmental and health loads in cities and urban regions are distributed unequally. Pursuing the objective to achieve environmental justice, this result should be paid more attention in the future. In the presentation, the methodology and most important results of the study will be presented. Further consequences of the results will be discussed against the background of the concept of ‘environmental justice’ and potential measures to achieve a reduction of PM10 loads within the environmental zone thus improving the liveability and functionality of human urban habitats.