Indoor particulate matter (PM2.5) in Malaysian academic building: Elemental characterization and source apportionment

Abstract

This study aims to determine the elemental compositions of indoor particulate matter (PM2.5) in two selected academic buildings, with emphasis on source apportionment using a multivariate receptor model. PM2.5 samples were collected from lecture halls, laboratories and lecturer offices at the Ministry of Health Training Institute of Sungai Buloh (S1) and the Ministry of Health Training Institute of Sultan Azlan Shah (S2). Sampling took place over 8 h using a low volume sampler (LVS). In this study, various scientific methods such as standard methods for air quality analysis as well as Principal Component Analysis (PCA) and Multiple Linear Regression (MLR) were applied in order to investigate the elemental characterizations and source apportionment of PM2.5, respectively. The PM2.5 compositions for water-soluble ionic species (WSIS) and trace metals were analysed using ion chromatography (IC) and inductively coupled plasma-mass spectrometry (ICP-MS), respectively. Results showed that the mean PM2.5 concentration at S1 (108 ± 39.5 µg m−3) was higher than S2 (91.1 ± 36.6 µg m−3). PCA-MLR analysis revealed that biomass burning (48%) and building material/crustal origin (81%) were the major sources of indoor PM2.5 for S1 and S2, respectively. Modifications and improvements to ventilation systems could be implemented in order to maintain a good health of the building occupants as outside sources may contribute to the presence of pollutants in these buildings.