CHARACTERIZATION OF CHEMICAL SPECIES IN UNIVERSAL SAMPLER (PM_2.5 AND PM_2.5-l0) AEROSOLS IN SUBURBAN AREA OF CENTRAL TAIWAN

摘要

Aerosol samples of particulate and chemical species for PM_10 (particulate matter with aero- dynamic diameters less than l0 pm) collected by Universal sampler were studied from June to August 1998 in the suburban area of central Taiwan. The ratios of PM_25/ PM_25 displayed that the fine particles (particle size < 2.5 μm) are prevailing in the suburban site. Ion Chromatography was used to analyze for the water-soluble ions: su1phate and nitrate in the Universal samples. Also, the collected samples were analyzed by atomic absorption spectrophotometry for the eleinental analysis of Ca, Fe, Pb, Cu and Cr. The results indicated that the crustal elements (Ca and Fe) and resuspended matters were dominated in the coarse particulate mode while the anthropogenic elements (Cr, Pb, Cu) and sulphate components are mainly in the fine particle fraction. The results also showed that the sulphate and nitrate make the largest portion of the chemical species collected by Universal sampler (PMl0). The concentrations of heavy metals in THU are generally high, owing to the higher motor vehicle and industrial density nearby. The degree of pollution from this source differs from day to day, depending on the motor vehicle density.