Assessment of wintertime atmospheric pollutants in an urban area of Kansai, Japan

作者：Ma CJ^*; Oki Y; Tohno S; Kasahara M

来源：Atmospheric Environment, 2004, 38(19): 2939-2949.

DOI：10.1016/j.atmosenv.2004.03.028

• particulate matter
• source profile
• PIXE
• wintertime
• carbon
• aerosol dispersion

An intensive measurement of particulate matter and gaseous materials was made to assess the characteristics of wintertime atmospheric pollutants in an urban area of Kansai, Japan. Sampling was performed by a combination of filter pack sampler and low-pressure Andersen impactor (LPAI). Particle-induced X-ray Emission (PIXE) and Thermal/Optical Reflectance (TOR(R)) methods were employed in analyzing element and carbon, respectively. The concentrations Of SO2, NOx, and PM2.5 monitored during our intensive measurement show a strong time serial variation. PM2.5 levels are higher in the daytime with an average level of 21.3 mugM(-3). Most of the peaks for NOx were regularly found in the morning throughout the campaign duration. The number concentration of particles larger than 0.3 mum appears dominated by the ultrafine particles ranged between 0.3 and 0.5 pm. The size distribution of elemental concentration as a function of water solubility was investigated. Organic carbon (OC) concentration shows the strong size distribution with the main peak formed in a range of 0.29-0.67mum, while elemental carbon (EC) is principally enriched in a range of 0.12-0.29 mum ultra fine fraction. TC (OC + EC) fraction accounts for 42.5% and 26.2% of the mass concentration in fine particle fraction (< 1.17 mum) and coarse particle fraction ( > 1.17 mum), respectively. The simulated backward aerosol dispersion with the surface wind roses for three events of high PM2.5 mass concentration indicates that aerosol dispersions might be originated from the emission sources of Osaka and Shiga. Also the possibility of long-range transportation of fine particulate matter from the domestic areas of Japan, Taiwan, and Pacific Ocean was still raised. The result of factor analysis indicates that automobile exhaust, fossil fuel combustion, refuse incineration, iron industry, and soil originated particles contribute the major portion Of PM2.5 in our sampling area.

• 出版日期2004-6