The Use of Principal Component Analysis for Source Identification of PM_2.5 from Selected Urban and Regional Background Sites in Poland

Institute of Environmental Engineering, Polish Academy of Sciences, 34 M. Skłodowska-Curie St., 41-819 Zabrze, Poland

^* Corresponding author: barbara.blaszczak@ipis.zabrze.pl

Abstract

The paper reports the results of the measurements of water-soluble ions and carbonaceous matter content in the fine particulate matter (PM_2.5), as well as the contributions of major sources in PM_2.5. Daily PM_2.5 samples were collected during heating and non-heating season of the year 2013 in three different locations in Poland: Szczecin (urban background), Trzebinia (urban background) and Złoty Potok (regional background). The concentrations of PM_2.5, and its related components, exhibited clear spatiotemporal variability with higher levels during the heating period. The share of the total carbon (TC) in PM_2.5 exceeded 40% and was primarily determined by fluctuations in the share of OC. Sulfates (SO₄^2-), nitrates (NO_3^-) and ammonium (NH₄⁺) dominated in the ionic composition of PM_2.5 and accounted together ~34% (Szczecin), ~30% (Trzebinia) and ~18% (Złoty Potok) of PM_2.5 mass. Source apportionment analysis, performed by PCA-MLRA model (Principal Component Analysis – Multilinear Regression Analysis), revealed that secondary aerosol, whose presence is related to oxidation of gaseous precursors emitted from fuel combustion and biomass burning, had the largest contribution in observed PM_2.5 concentrations. In addition, the contribution of traffic sources together with road dust resuspension, was observed. The share of natural sources (sea spray, crustal dust) was generally lower.