Comparative study of the atmospheric chemical composition of three South American cities

Structural signatures of water-soluble organic aerosols in contrasting environments in South America and Western Europe

“…This would be indicative of exceptional atmospheric conditions for attaining similar amounts of secondary organic components across the different European and South American locations. However, the observed low WSOM/ PM ratios (<1.3%) may be explained by the significant presence of apparently chemically reduced OA probably related to freshly emitted traffic aerosols in Medellín, Bogota, Buenos Aires, Lima, PV, and S. Paulo (Vasconcellos et al, 2011). Also of note, Bogota presents the lowest median value for the WSOM/PM ratio among the South American sites.…”

“…The sampling site is mainly influenced by residential and vehicular emissions (Vasconcellos et al, 2011). In Lima (8.5 million inhabitants; data from the National Statistical System of Peru), capital of Peru, the sampling campaign was carried out in Campo de Marte, the biggest urban park, localized in the central region of the city.…”

“…In Bogota, capital of Colombia, with approximately 8 million inhabitants and about 1.2 million vehicles, twelve 24 h PM 10 samples were collected from November 24th to December 9th (2008), during the wet season, on quartz fibre filters (20.3 Â 25.4 cm; Whatman QM-A), at a site with strong vehicular emissions. Additional details on aerosol sampling in Bogota can be found in the study of Vasconcellos et al (2011). At Buenos Aires (14 million inhabitants in the metropolitan area), Argentina, thirteen 24 h PM 10 samples were collected from August 14th to September 15th (2008), on quartz fibre filters (20.3 Â 25.4 cm; Whatman QM-A).…”

“…On the other hand, comprehensive structural identification within the complex aerosol WSOC mixture has been rarely reported for Southern Hemisphere locations. Most field studies within this region have included measurements of ambient concentrations of OC, elemental carbon (EC), and WSOC, specific organic markers (e.g., n-alkanes, PAHs, and levoglucosan), or the amount of hydrocarbon-like and oxygenated OA components [e.g., in Brisbane (Australia), Tanzania (rural background site), São Paulo (Brazil), Rondônia (Amazon Basin, Brazil), Buenos Aires (Argentina), Bogota (Colombia), and Santiago (Chile)] Mayol-Bracero et al, 2002;Tagliavini et al, 2006;Vasconcellos et al, 2010Vasconcellos et al, , 2011Mkoma and Kawamura, 2013;Crilley et al, 2014;Souza et al, 2014;De Oliveira Alves et al, 2015;Villalobos et al, 2015). Although these studies have provided a glimpse into the bulk chemical makeup of OA, the current understanding of the role of aerosol WSOC in global climate change still is incomplete.…”

Size-segregated particulate matter and carboxylic acids over urban and rural sites in Londrina City, Brazil

“…Due to their strong hydrophilic and hygroscopic properties, dicarboxylic acids are able to reduce surface tension and affect the formation of cloud condensation, consequently affecting the global radiation balance. 10,[28][29][30] 39 recently performed a comparative study of the atmospheric chemical composition of Bogotá, Buenos Aires and São Paulo Cities and found that samples from São Paulo showed the highest concentrations of species analyzed on PM 10 (n-alkanes, water-soluble ions, polycyclic aromatic hydrocarbon, metals and metalloids) among all the sites. Also, Gioda et al 40 performed studies concerning chemical composition, sources, solubility and transport of aerosol trace elements in Rio de Janeiro City.…”