Weekly samples of total suspended particles in air (TSP) were taken in south-east Beijing for a two-year period continuously from August 2005 to August 2007. Mass concentrations varied between 76 and 1028 microg m(-3) with an average concentration of 370 microg m(-3) for the whole period. The chemical composition and the mass concentration of aerosols in combination with meteorological data are reflecting specific influences of distinct aerosol sources on the pollution of Beijing's atmosphere. Lead (Pb), titanium (Ti), zinc (Zn) and copper (Cu) concentrations were chosen as indicator elements for different sources. Their amounts considerably varied over the course of the year. Element ratios, such as Pb/Ti, supported the distinction between periods of predominant geogenic or anthropogenic caused pollution. However, the interactions between aerosols from different sources are numerous and aerosol pollution still is a big and complex challenge for the sustainable development of Beijing.