The PM10 compositions, sources and health risks assessment in mechanically ventilated office buildings in an urban environment

Office buildings can be considered a “second home” for working people and so the contribution of pollutants in this indoor environment to a person’s overall exposure is significant. The aims of this study were to examine the composition of PM 10 and the sources influencing the indoor and outdoor office environments. The PM 10 sampling was performed using a mini-vol portable sampler at two sampling sites from May to August 2014 for daily 24 h sampling. The concentrations of ionic species (F − , Cl − , NO 3 − , SO 4 2− ) were analysed using ion chromatography while the concentration of major elements (Mg, Ca, K, Na) and trace elements (Mn, Ni, Fe, Cu, Zn, Pb, Cr, Cd, Al) were determined by inductively couple plasma-mass spectrometry (ICP-MS). The concentration of NH 4 + was determined using the indophenol blue method. The results showed that the average concentrations of PM 10 were 61.3 ± 27.0 μg/m 3 (indoor) and 101 ± 42.8 μg/m 3 (outdoor) with an indoor/outdoor ratio value of