Chemical Compositions of PM2.5 at Two Non-Urban Sites from the Polluted Region in Europe

Abstract

The study presents the analysis of measurement results for the ambient mass concentrations of fine particulate matter (PM 2.5 ). The 24-h PM 2.5 samples were collected in the heating and non-heating seasons at two regional background sites in Southern Poland in 2011-2013. The percentage of the secondary organic and inorganic matter in PM 2.5 was calculated.Over the whole measurement period, the mean PM 2.5 concentration was 31.56 µg m -3 and 24.92 µg m -3 in Racibórz and Złoty Potok, respectively. Regardless of the season, the total carbon percentage in PM 2.5 was comparable at both sites and amounted ~40%. There were no visible seasonal variations in the secondary organic carbon (SOC) share in PM 2.5 . The mean percentage of the primary organic carbon (POC) in PM 2.5 was higher than the SOC percentage at both locations. The mean contribution of the water-soluble ions in the PM 2.5 mass was lower than the TC percentage, with values 20.35% (Złoty Potok) and 33.56% (Racibórz). The total share of the secondary ions (SO 4 2-, NO 3 -and NH 4 + ) in PM 2.5 was comparable in both measurement periods.It was shown that PM 2.5 at regional background sites in Southern Poland is significantly different than at similar stations across Europe. It is reflected by higher concentrations of PM 2.5 and its main components and lower percentage of the secondary ions in the PM 2.5 mass. The carbonaceous matter percentage in PM 2.5 is higher than in other parts of Europe.

The Use of Principal Component Analysis for Source Identification of PM2.5 from Selected Urban and Regional Background Sites in Poland

“…1.]. It should be mentioned that concentrations of main components in analysed PM2.5 samples were comparable for Trzebinia and Zloty Potok sites from Southern Poland -one of the regions of Poland with the highest degree of urbanization and pollution of all the components of the environment [11]. The combined share of secondary inorganic ions in PM2.5 from investigated areas was lower (eg.…”

“…and Mg 2+ ions were not taken into account, due to a large number of results below the detection limit. Bearing in mind the chemical behaviour of organic carbon [11], the secondary organic carbon (SOC) and primary organic carbon (POC) were considered as independent variables. The method dor the determination of SOC and POC content in PM2.5 was specified in previous works [11].…”

“…Much higher PM2.5 concentrations were found during the heating period than the non-heating one, with the values respectively: 24.4 and 8.7 µg/m 3 (Szczecin), 39.2 and 16.7 µg/m 3 (Trzebinia), 34.0 and 16.3 µg/m 3 (Złoty Potok). These differences can be attributed to unfavourable meteorological conditions in winter (lower wind speeds and mixing heights, frequent temperature inversions) and, what is more important, an increase in the activity of local emission sources of PM, especially biomass burning and fossil fuel combustion in domestic furnaces and in small local heating plants [10][11][12]. The concentrations of total carbon (TC) in PM2.5, averaged for a whole measuring period, equalled 6.65 µg/m 3 , 11.03 µg/m 3 and 10.05 µg/m 3 , respectively for Szczecin, Trzebinia and Złoty Potok.…”

“…Carbonaceous matter (elemental carbon -EC, organic carbon -OC) and inorganic ions, have the highest contribution to PM mass [9,10]. The latter, especially sulfates (SO4 2-), nitrates (NO3 -) and ammonium (NH4 + ), are an important constituent of the secondary inorganic aerosol (SIA) [11,12]. This component greatly affects the concentration and composition of fine PM, both in areas remote from emission sources, as well as in urban areas [10][11][12][13][14].…”

“…The latter, especially sulfates (SO4 2-), nitrates (NO3 -) and ammonium (NH4 + ), are an important constituent of the secondary inorganic aerosol (SIA) [11,12]. This component greatly affects the concentration and composition of fine PM, both in areas remote from emission sources, as well as in urban areas [10][11][12][13][14]. The PM concentrations and chemical composition can vary significantly in time and space, which depend on the main emission sources and chemical reactions occurring in the atmosphere [12,15].…”