Characterizations of resuspended dust in six cities of North China

Particulate matter is the chief pollutant of urban ambient air in North China, and the contribution of resuspended dust to urban ambient PM10 is very high. Studies on source apportionment for urban ambient particulate matter and resuspended dust were carried out in six north cities (Tianjin, Jinan, Shijiazhuang, Taiyuan, Urumqi and Yinchuan) during 2000 and 2002. About 150 resuspended dust samples were collected in these cities and then resampled PM10 from them in resuspension chamber in the lab. Samples were analyzed by ICP and X-ray fluorescence for 19 elements (Na, Mg, Al, Si, P, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Br, Ba and Pb), ion chromatography for 4 ions (Cl−, NO3−, SO42− and NH4+) and carbon elemental analyzer for TC and OC. Crustal elements and TC are in abundance in resuspended dust. Zn, Cu, and Cr are enriched. According to the results of CMB receptor model, resuspended dust was the greatest source type of ambient PM10 in six cities, and soil, cement and coal combustion were the main contributors to resuspended dust.