Assessment and source apportionment of PM_2.5 in a major Latin American port: elevated concentrations from traffic in the Great Atlantic Forest Reserve

Ports are pivotal to the global economy but contribute significantly to environmental impacts, notably air pollution from local sources. Long-term exposure to atmospheric fine particulate matter (PM_2.5) poses severe health risks, including respiratory and cardiovascular diseases. This study investigates the source apportionment of PM_2.5 Paranaguá, a major Latin American port situated in a sensitive ecosystem and a marine protected area in the South Atlantic. In 2017, the mean PM_2.5 concentration at Paranaguá port was 15.3 ± 7.5 µg m^− 3, and 10% (n = 34) of the samples exceeding Brazil’s 24-hour environmental quality standard of (25 µg m^− 3). This level of PM_2.5 correlates with an 8% increase in the risk of general mortality risk in the port region. Four diagnostic tools were employed to estimate PM_2.5 sources from soluble ions, trace and major metal compositions, and black carbon (BC) fraction: (1) Polar plots using meteorological data; (2) Correlation analysis with daily ship and truck counts; (3) Enrichment factors; and (4) Positive matrix factorization (PMF). The results indicate that traffic is the predominant source of PM_2.5, primarily due to the extensive road transport of soy to the port. Given the anticipated continued dominance of road transport emissions, Brazil must implement measures to reduce traffic-related emissions. Aligning with the United Nations’ Sustainable Development Goal (SDG) 3.9, we recommend adopting environmentally responsible production models, such as agroecology and local productive systems to mitigate PM_2.5-related health risk.