Chemical Composition of Airborne Pm10 at Different Locations in Shanghai: Application of Source Apportionment Methodologies

Abstract:
The study was conducted by the Italian CNR and the Chinese EMC of Shanghai in the framework of the APEM project (Air Pollutants’ Emission Monitoring) and was aimed to analyze the chemical composition of the PM10 dust in Shanghai. During July 2007 PM10 was daily collected on quartz and Teflon membrane filters at three different locations in Shanghai: a construction site, a traffic site and an urban background site. Teflon and quartz filters were used to study the chemical composition of PM10; energy-dispersion, X-ray fluorescence, ion chromatography and thermo-optical analyser were used to assess the different chemical components. The daily mass concentration of PM10 was determined gravimetrically. The sampling and analysis of PM10 allowed a detailed characterisation of atmospheric particulate pollution. The relative weight of five sources of PM (crustal, sea-salt, anthropogenic primary, secondary inorganic and organic aerosol) was assessed during the period. In the construction yard the mean value of PM10 concentration was 121g/m3 and 100 g/m3 in the west (close to the working area) and east side, respectively. A high loading of crustal element was observed, indicating the strong influence of the construction yard operation in the PM10 emissions: crustal elements constituted, respectively, 39% and 33% of the total mass (47 g/m3 and 33 g/m3). The other two sites showed a mean concentration of 77 g/m3 at the traffic site, and 66 g/m3 at the urban background site, with a 22% and 14% of crustal components (17g/m3 and 9g/m3). Construction west has four times more crustal dust than background and twice than traffic site. The reconstructed chemical composition based on the average concentration of PM10 shows that the major component in Shanghai city dust are secondary inorganic (37%), crustal (29%), organics (17%), primary anthropogenic (15%) and sea salt (2%).

Keywords: Shanghai, Chemical analysis, Source Apportionment