Determination of multi-element profiles of street dust using energy dispersive X-ray fluorescence (EDXRF).

Street dust samples have been collected in different areas in Hong Kong associated with various levels of traffic and pedestrian flow, and the concentrations of 23 chemical elements have been determined using energy dispersive X-ray fluorescence (EDXRF). The 23 studied elements were Na, Al, Si, Cl, Ti, Ba, V, Cr, Mn, Fe, Co, K, Ca, Ni, Cu, Zn, As, Pb, Rb, Sr, Y, Zr and Sn. A profile for average street dust for Hong Kong has been determined by taking average values for different areas. The values for the Hong Kong street dust are commensurate with the values derived in previous investigations or for other countries, except that Hong Kong street dust has much higher Cl, Ca and As concentrations. A factor analysis gives four sources for the street dust in Hong Kong: namely, mixture of metallic dust and crustal material, vehicles, road pavement materials, and mixture of marine aerosols and crustal material.