Black carbon in urban atmospheres: source apportionment, mixing states, and implications for climate and respiratory health

Abstract

Black carbon (BC) is a major urban pollutant affecting climate and health. This review examines studies published between 2018 and 2026 on BC sources, mixing state, and impacts. Traffic emissions dominate developed cities, while biomass and residential combustion are major sources in developing regions. Particle mixing influences radiative forcing and respiratory deposition. Standardized measurements and integrated climate-health assessments are needed.