Identifying airborne metal particles sources near an optoelectronic and semiconductor industrial park

Abstract

The recently developed Central Taiwan Science Park (CTSP) in central Taiwan is home to an optoelectronic and semiconductor industrial cluster. Therefore, exploring the elemental compositions and size distributions of airborne particles emitted from the CTSP would help to prevent pollution. This study analyzed size-fractionated metal-rich particle samples collected in upwind and downwind areas of CTSP during Jan. and Oct. 2013 by using micro-orifice uniform deposited impactor (MOUDI). Correlation analysis, hierarchical cluster analysis and particle mass-size distribution analysis are performed to identify the source of metal-rich particle near the CTSP.Analyses of elemental compositions and particle size distributions emitted from the CTSP revealed that the CTSP emits some metals (V, As, In Ga, Cd and Cu) in the ultrafine particles (<1μm). The statistical analysis combines with the particle mass-size distribution analysis could provide useful source identification information. In airborne particles with the size of 0.32μm, Ga could be a useful pollution index for optoelectronic and semiconductor emission in the CTSP. Meanwhile, the ratios of As/Ga concentration at the particle size of 0.32μm demonstrates that humans near the CTSP would be potentially exposed to GaAs ultrafine particles. That is, metals such as Ga and As and other metals that are not regulated in Taiwan are potentially harmful to human health.