Characteristics of Ambient Particulate Matter at Elementary Schools in Taipei Metropolis

This study is aimed to characterize the ambient particulate matter at elementary schools in Taipei metropolis and their source, and their correlation to the corresponding data from the nearby air monitoring stations. The two elementary schools located in each light, moderate and heavy traffic area were for selected particulate sampling during August 2006 to April 2007. The samples were collected in campus by using 10-stage micro-orifice uniform deposit impactor（MOUDI）and weighted. In addition, the PM10 data from the nearby air monitoring stations of Taiwan Environmental Protection Administration were also adopted for comparison. The results show that the average mass concentration of the particulate sampling in six elementary schools ranged from 58.21 to 110.11 μg/m3, which all did not exceed the standard of Taiwan EPA, 24h PM10 of 125 μg/m3. The particle size distribution of particulate matter at six elementary schools almost fitted log-normal distribution. The mass medium diameter ranged from 0.191∼4.463 μm. The size distribution of particulate matter can be summed up the bimodal type, and the primary peak occurred in fine particle size range, and second peak was in the ranges from 3.2∼5.6 μm. The analysis of variance（ANOVA）indicates the positive correlation between the mass concentration of particulate matter and traffic density（p＝0.047）. The average mass concentration in spring, autumn and winter were 84.98±22.20 μg/m3, 65.30±22.05 μg/m3, 90.66±39.03 μg/m3, respectively. The particulate matter mass concentration measured at six elementary schools did not consistently correlate with the PM10 data from the nearby air monitoring stations.