Elemental composition of springtime aerosol in Chillán, Chile

An aerosol monitoring study was established to measure ambient aerosol composition and study air pollution for one sampling site located at the University of Concepción, Chillán Campus. Chillán, a typical agricultural city in the central valley, is located in the southern Bio Bío Region of Chile. The Chillán Campus is located approximately 4 km north of the cityʹs downtown. The aerosol monitor operated on the campus from 9 October to 9 December, 1998. The study employed an IMPROVE sampler with an Anderson PM10 inlet at 3 m collecting PM10 on 25 mm Teflon membrane filters. The filters were weighed before and after sampling to obtain mass concentration, then proton induced X-ray emission and X-ray fluorescence analysis were used to measure the concentration of 22 elements to levels below . Moderate aerosol concentration was observed (up to ). The main aerosol particle source in Chillán is resuspended soil dust, which accounts for 55% of the PM10 aerosol. The presence of Br, Pb and V and other heavy metals in analyzed samples points to traffic emissions in the city. Aerosol associated with transportation activities accounts for 11% of the PM10 mass. Non-transportation organics, associated with hydrogen measured by proton elastic scattering analysis, are an important component accounting for 19% of the PM10 mass. Sulfate particles account for 3%. In addition, presence of several trace metals, including Mn, Zn, Cu, Ga, As, and Sr in our samples suggests the presence of industrial emissions in the city.