TY - JOUR T1 - Isotopic characterization of aerosol organic carbon components over the eastern United States JF - Journal of Geophysical Research-Atmospheres Y1 - 2012 A1 - Wozniak, Andrew S. A1 - Bauer, James E. A1 - Dickhut, Rebecca M. A1 - Xu, Li A1 - McNichol, Ann P. AB - Carbon isotopic signatures (delta C-13, Delta C-14) of aerosol particulate matter total organic carbon (TOC) and operationally defined organic carbon (OC) components were measured in samples from two background sites in the eastern U. S. TOC and water-soluble OC (WSOC) delta C-13 values (-27 to -24 parts per thousand) indicated predominantly terrestrial C-3 plant and fossil derived sources. Total solvent extracts (TSE) and their aliphatic, aromatic, and polar OC components were depleted in delta C-13 (-30 to -26 parts per thousand) relative to TOC and WSOC. Delta C-14 signatures of aerosol TOC and TSE (-476 to +25 parts per thousand) suggest variable fossil contributions (similar to 5-50%) to these components. Aliphatic OC while comprising a small portion of the TOC ( VL - 117 N1 - id: 2252; PT: J; TC: 1; UT: WOS:000306237000001 JO - Isotopic characterization of aerosol organic carbon components over the eastern United States ER -