Contributions of road dust resuspension to the airborne particle concentrations in Taipei

ABSTRACT The high concentrations of airborne particles have been one of the main air pollution problems in Taipei, Taiwan. In this study, the possible sources of airborne particles were investigated using concentration profile and chemical composition. The vertical concentration profile of TSP was measured at 1.5 m, 11 m, and 38 m above ground. The concentrations of TSP at 1.5 m above ground are always greater than 300 µg/m3; and even up to 1230 µg/m3, while those at 11 m above ground are only half of these values. The concentrations at 38 m above ground are only about half of those at 11 m above ground. Similar concentration profiles are found for Mg, Ca, Pb, Fe, and Zn measured and the enrichment factors with respect to the composition of road dust are generally less than 3. Therefore, there is a not upward flux of airborne particles from ground. The net upward fluxes are estimated to be about 100 ton/yr/km1 from the vertical concentrations profiles and particle size distributions. The particle resuspen...