TY - JOUR AB - This study addresses the pressing issue of black carbon (BC) pollution in urban areas, focusing on two locations in the Philippines: Quezon City’s East Avenue (QCG, roadside urban environment) and Manila’s North Port. We found that organic aerosol particles (OA) made a greater contribution (80%) to total submicron particulate matter compared to inorganic aerosol (IA) (20%). The mean hourly average equivalent black carbon (eBC) mass concentration at the QCG site (35.97 ± 16.20 mg/m3) was noticeably higher compared to the Port (10.27 ± 5.99 mg/m3), consistent with trends in other Asian cities. Source apportionment analysis identified eBC related to transport emissions (eBCTR) as the predominant contributor to eBC, accounting for 86% at the Port and 80% at QCG. Diurnal patterns showed the highest eBCTR mass concentrations (47.69 ± 9.34 mg/m3) during morning rush hours, which can be linked to light-duty vehicles. Late-night (10 pm–12 am) high concentrations (30.63 ± 8.45 mg/m3) can be associated with heavy diesel trucks at the QCG site. Whereas at the Port site, hourly average higher eBCTR concentration (12.24 ± 3.65 mg/m3) during morning hours (6 am–8 am) can be attributed to the traffic of heavy-duty trucks, trollers, diesel-powered cranes and ships. Compared to the QCG site, a lower eBC concentration at the Port site was favoured by the more open environment and higher wind speed, facilitating better pollutant dispersion. The mean hourly average concentrations of PM2.5 and PM10, measured using an Aerodynamic Particle Sizer, consistently exceeded the air quality standards set by the World Health Organization and the Philippine Clean Air Act at both sites. This study highlights the persisting BC pollution in developing regions and calls for scientifically based strategies to mitigate the air quality crisis. AU - Gill, T.* AU - Kecorius, S. AU - Kandrotaitė, K.* AU - Dudoitis, V.* AU - Madueno, L.* AU - Wiedensohler, A.* AU - Poulain, L.* AU - Vallar, E.A.* AU - Galvez, M.C.D.* AU - Byčenkiene, S.* AU - Plauškaite, K.* C1 - 73642 C2 - 57154 CY - Powstancow Waszawy 55, Pl-81-712 Sopot, Poland TI - Carbonaceous aerosol particle sources in Manila North Port and the urban environment. JO - Oceanologia VL - 67 IS - 1 PB - Polish Acad Sciences Inst Oceanology PY - 2025 SN - 0078-3234 ER -