Seasonal variation of the elemental composition of particulate matter collected in a small town near Warsaw, Poland

Four seasonal sampling campaigns successively in April, July, September 2008 and February 2009 took place at Swider, a town located to the south-east of Warszawa, Poland. Three particle size fractions of particulate matter were collected by a NILU (The Norwegian Institute for Air Protection, Norway) sampler. The following elements were determined by the energy dispersive X-ray fluorescence (EDXRF) method: K, Ca, Ti, Cr, Mn, Fe, Cu, Zn, Br and Pb. The highest mean mass concentrations in fine and medium fractions were observed in April 2008 and February 2009. For a coarse fraction, the highest values of mass concentrations were observed in April and September 2008. Ca, Mn and Fe existed mainly in the coarse fraction. These elements probably came from the southern direction. Zn was divided between three fractions equally. In February 2009 the highest Zn concentrations were observed in the medium fraction. Pb existed mainly in the fine and medium fractions. The highest values of Pb concentrations were observed in February 2009. Bromium existed in the fine fraction. Correlations were observed between Ca, Mn and Fe concentrations. Correlation factors were about 0.8 for the coarse fraction. For other analyzed elements, the correlation coefficients were small. Basing on the backward trajectories and elemental concentrations of particulate matter (PM), it was confirmed that in winter the main influence on air quality is caused by pollution coming from coal combustion in local houses, heat and power plants working in urban areas. In summer the main influence on air quality is caused by pollution from sources in rural cultivable areas. The improvement of air quality is possible by decreasing the emission, using coal with a small level of harmful compounds and whole elimination of plant preventive agents and using fertilizers with a small content of unwanted elements. (authors)