1. Bartłomiej Pietras Institute of Geography; Pedagogical University,ul. Podchorążych 2, 30-085 Kraków; bpietras86@gmail.com Introduction The problem of air quality and its impact on Cracow citizens' health is still a major environmental and social issue. Meteorological conditions, as well as local and distant emitters, play an essential role in the pollution concentration. Such correlations could be observed in the way atmospheric conditions affect transport and dispersion of the airborne substances, which influences the pollution concentration in a given place and time. The exceeded levels of allowable dust concentration could also be partially caused by natural sources. Fig. 1. Backward trajectories of air particles from the model HYSPLIT: a.) 22 May 2012; b.) 26 December 2012 a.) b.) Fig. 2. Maps of synoptics situation: a.) 22 May 2012; b.) 26 December 2012 a.) b.) The chemical composition of aerosols is determined by their origin (natural, anthropogenic) and the type of source area (physiographical conditions, land development). Natural aerosols are characterized by increased participation elements inter alia silicon, aluminum, calcium, magnesium. Aerosols of anthropogenic origin show increased contribution of chromium, iron and manganese. In addition to the chemical composition as an important criterion indicating the origin of aerosols is their shape. Natural dust:Anthropogenic dust: Conclusions 1.Dominant influence on the occurence of days with adverse aerosanitary conditions have high pressure situations, characterized by low horizontal pressure gradient with inversion of temperature. 2.Advection of air masses from west, south and south-east enhances on dust concentration of PM10 in Krakowie by inflow of pollutants from industrialized areas neighboring countries (transboundary transfer of pollution over long distance). 3.Contribution of natural aerosols in the analyzed material proves that exceeded the permissible limits of pollutants concentration may be partly caused by a natural part of dust. 4.The analyzed aerosols particles of anthropogenic origin are characterized by increased participation chromium, iron and manganese. In the case of natural aerosols in chemical composition dominates silicon, aluminum, calcium, magnesium. composition (wt%): O - 100% composition (wt%): O – 63,3%, Si – 18,1%, Al – 13,2%, Na – 2,4%, K – 1,4%, Fe – 1,0% composition (wt%): O – 48,5%, Si – 30,7%, Al – 10,4%, Na – 7,4%, Ca – 1,7%, composition (wt%): O – 59,7%, Ca – 25,0%, S – 14,3%, K- 0,7%, Si – 0,4% Material and methods The analytical material would consist of 70 samples of dust pollutions collected on polycarbonate membranes (0,4 µm) using a personal aspirator, GilAir plus STP. Collection of the material will take place with the air inflow from given sectors, based on the analysis of the trajectories of reverse particles in the air from HYSPLIT model (Hybrid Single – Particle Lagrangian Integrated Trajectory) which calculates the path of air molecules (Fig. 1). Analysis of size, shape and chemical composition of the particles using a scanning electron microscope (HITACHI S-4700) with field emission using an EDS spectrometer. Results Episodes of high concentrations of particular matter (PM10 < 10 mm) was observed in nonadvection circulation types – anticyclonic center and wedge. In advection circulation types The deterioration of aerosanitary conditions takes place when, inter alia, the air flows from western and south-western sectors. recent studies showed that, apart from local pollution emitters, the levels of PM10 concentration are also affected by distant emission sources (cross-border pollution transmission) located in the Benelux countries, in Germany near Frankfurt, Hamburg, Dresden or Leipzig, on the Slovak-Hungarian border near Budapest, and in Austria near Vienna (Fig. 2). composition (wt%): O – 62,8%, Ca – 20,4%, Mg – 15,4%, Fe – 1,5% Meteorological conditions of concentration aerosols and attempt to determine their origin