Author(s)

O. F. Carvacho, J. E. Celis, K. Trzepla-Nabaglo, L. L. Ashbaugh & R. G. Flocchini

Abstract

Transportation is widely recognized to be a significant and increasing source of air pollution. In the city of Chillán there are many public cars, buses and trucks that have been retired from circulation in the metropolitan region (capital city of Santiago) due to strict regulation from local environmental authorities. In order to study air pollution in Chillán, a typical semi-agricultural central valley city located in the southern Bio-Bio Region of Chile, an aerosol monitoring study was established to measure ambient aerosol composition. The contributions of private cars, public cars, buses and delivery trucks were examined at a sampling site located downtown. The aerosol monitor was operated from September 2001 to September 2002. The study employed an IMPROVE PM10 sampler with Anderson inlet at 3 meters above ground collecting PM10 on Teflon membrane filter, nylon and quartz filter. Sulfate concentrations were lower than soil, nitrate, elemental and organic carbon, which contributed significantly to PM10 mass. Soil accounted for 25% of the PM10 mass and carbon particles accounted for just over 50%. Transportation sources appear to be primary sources of the carbon and soil particles. The remaining mass was mostly secondary ammonium nitrate and ammonium sulfate. Some metals, such as V, Ni, Br, and Pb, were measured frequently at the downtown site. They did not contribute appreciably to the PM10 mass, but underscore the importance of transportation sources to measured particulate matter. Keywords: PM10, aerosol speciation, sulfate, nitrate, organic and elemental carbon, elemental concentrations, soil.

Keywords

PM10, aerosol speciation, sulfate, nitrate, organic and elemental carbon, elemental concentrations, soil.