Fine particulate matter source attribution for Southeast Texas using 14C/13C ratios

Abstract
Radiocarbon analyses of fine particulate matter samples collected during the summer of 2000 in southeast Texas indicate that a substantial fraction of the aerosol carbon at an urban/suburban site (27–73%) and at a rural, forested site (44–77%) was modern carbon. Data from emission inventories and additional ambient measurements indicate that the most likely sources of this modern carbon are biomass burning fires and biogenic secondary organic aerosol.