Abstract Air pollution is a critical environmental issue influenced by both natural and anthropogenic sources. We hypothesized that PM 2.5 chemical composition varies spatially due to local anthropogenic sources, soil resuspension, and biomass burning. This study analyzed particulate matter (PM 2.5 ) concentrations and chemical composition (black carbon (BC), elements, and ions) in three locations in Rio de Janeiro state: Gávea (urban area), PARNASO (environmental preservation area), and Campos