Tracing organic pollutants in particulate Matter: Source identification and implications for air quality and public health

Air pollution significantly impacts public health and environmental quality, making it crucial to identify its sources and chemical composition. This study analyzes organic compounds in atmospheric particulate matter, including polycyclic aromatic hydrocarbons (PAHs), nitro-PAHs, oxy-PAHs, aliphatic hydrocarbons, and anhydrosugars. Samples were collected from three locations with varying types and levels of human activity in Rio de Janeiro, Brazil: Gávea (urban), PARNASO (environmental protection area), and Campos dos Goytacazes (metropolitan area linked to sugarcane burning). While PM_2.5 concentrations fell within Brazilian air quality standards, 63 % of samples exceeded World Health Organization guidelines. PAH concentrations were highest in PARNASO (385 ± 639 pg m⁻³), followed by Campos dos Goytacazes (236 ± 320 pg m⁻³) and Gávea (184 ± 291 pg m⁻³). High molecular weight PAHs were prevalent and associated with gasoline combustion. Retene, a 5-ring PAH, indicated sugarcane burning, whereas levoglucosan was a reliable marker for biomass combustion. Nitro-PAHs and oxy-PAHs in lower concentrations provided additional insights into combustion sources. The findings underline the impact of human activities on air quality and highlight the need for continuous monitoring of PAHs and their derivatives, particularly in vulnerable areas like PARNASO.