Journal of the Brazilian Chemical Society
Print version ISSN 0103-5053
LOYOLA, Josiane et al. Trace metals in the urban aerosols of Rio de Janeiro city. J. Braz. Chem. Soc. [online]. 2012, vol.23, n.4, pp. 628-638. ISSN 0103-5053. http://dx.doi.org/10.1590/S0103-50532012000400007.
From January to April 2009, samples of suspended particles (TSP) and particulate matters (PM10 and PM2.5) were collected from a well-characterized urban area that is highly impacted by vehicular traffic. The metal concentrations in these samples were determined using ICP-OES (inductively coupled plasma-optical emission spectroscopy). Ca, Mg, Fe and Al were the most abundant metals present in TSP and PM10, with concentrations higher than 427 ng m-3. In PM2.5, the most abundant metals were Fe and Ca (307 and 60 ng m-3, respectively), while the concentrations of Mg, Zn and Cu were approximately 20 ng m-3. For PM10 and PM2.5, high correlations were obtained for Ca, Mg and Al, while the correlation of Ca and Mg with Fe was poor, thereby indicating that Ca, Mg and Al probably originate mainly from the resuspension of dust, while Fe may also be originated from an additional source, such as brake wear. Anthropogenic elements (Zn and Cu) had low correlation factors, suggesting different emission sources. The presence of Cu may be linked to the abrasion of brakes, and Zn may be attributed to tire wear. In fine particles, Ca, Mn, Fe, Zn and Cu were present in higher ratios than in crustal material. Because these particles are mainly observed due to the combustion processes, they may be present in gasoline, oil and lubricants. Fe was correlated with Mn, while correlation factors between Ca and Mg were relatively lower.
Keywords : total particulate matter; PM10; PM2.5; trace metals; vehicle emissions.