SAO-PAULO AEROSOL CHARACTERIZATION STUDY

The Sao Paulo Metropolitan area (SPMA) is characterized as having one of the worst air pollution problems in Brazil, with frequent violation s of air quality standards for particulate matter. This paper presents the results of a receptor model source apportionment study carried ou t to develop a quantitative database on which a control strategy could be developed. The study was conducted in four sites with distinct lan d uses. Fine, coarse (CP), and total suspended particles (TSP) samples were collected on Teflon and glass filters and analyzed by x-ray fluo rescence (XRF), ion chromatography, and thermal evolution. The sources were characterized by similar methodology. Chemical mass balance (CMB ) receptor modeling indicated that carbonaceous material plays an impo rtant role in the aerosol composition; that the three major source cat egories contributing to the fine particles are vehicles, secondary car bon, and sulfates; and that the main contributors to CP and TSP are ro ad dust and vehicles. All sampling sites presented the same general pa ttern in terms of source contribution, although this contribution vari ed from site to site.