Use of levoglucosan, potassium, and water-soluble organic carbon to characterize the origins of biomass-burning aerosols

► The aerosol chemical composition was highly affected by biomass burning. ► Most of the levoglucosan (up to 89%) was present in small particles (<1.5 μm). ► Biomass burning was an important source of WSOC. ► The levoglucosan:K+ ratio in fine particles (sugar-cane burning) was 0.24.