We characterized the PM10 in Distrito Federal, Central Brazil, which is a region close to agricultural areas, neighboring the Amazon Forest, and impacted by biomass burning. We quantified the water-soluble ions (Na+, K+, Mg2+, Ca2+, Cl-, NO3-, SO42-), elements (Al, Ba, Cu, P, Zn), total carbon, 13C isotope and evaluated its morphology from January 2018 to September 2019. PM10 sampled at three stations (Fercal - cement industry zone; Rodoviária – bus station with busy traffic ways; and Zoo – background area) were collected by High-Vol collectors (1 m3 min-1/24h of flow) and analyzed by IC, ICP-AES, and SEM-EDS. For the whole sampling campaign and station, the descending mean ions concentrations (in ng.m-3) were: Ca2+ > SO42- > Na+ > NO3- > Cl- > K+ > Mg2+. The main water-soluble elements (in pg.m-3) were: Al > Ba > Zn. The maximum values of all chemical variables were registered during the dry season, mainly in the Fercal and Rodoviária stations where the total carbon correlated with PM10 mass. The δ13C values, ranging from -19.60 to -24.12‰ at the Zoo and Rodoviária stations, are closer to burning δ13C values of C3 plants of Cerrado vegetation. According to the factor analysis, biomass burning sources in the dry season (May to September) could explain 31% of the total variance in the particulate matter water-soluble chemical composition. Crystallized minerals of Ca and Si oxides were related to natural sources and the cement industry. Biological particles and some spherical ones composed of C, N, O, Si, and Ca with adsorbed transition metals (Ni, Cu, and Zn) were associated with the origin of pollen, spores, plants, or animal traces. Currently, we are studying the PM10 dispersion by backward trajectories, quantifying Sm, Nd, and Sr isotopes and the magnetic properties of that PM10 samples to untangle the atmospheric sources.
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