Carbon and nitrogen isotopic analysis of atmospheric organic matter

A new method is presented to analyse the isotopic abundance of organic matter in aerosols. The method involves water extraction of aerosol filters, elution through an ion retardation resin to remove inorganic components and lyophilising the eluent to concentrate the fraction prior to isotopic analysis. Results of analyses of a series of aerosol samples collected in the UK, for the fraction of organic matter passing through the resin, are presented. Carbon and nitrogen isotopic abundances ranged from −23.0‰ to −35.5‰ (versus PDB) and −14.6‰ to +12.5‰ (versus AIR), respectively.