CHARACTERIZATION OF CARBONACEOUS AEROSOLS IN THE NAGOYA URBAN AREA .1. ELEMENTAL AND ORGANIC-CARBON CONCENTRATIONS AND THE ORIGIN OF ORGANIC AEROSOLS

Concentrations of elemental carbon (EC) and organic carbon (OC) were determined in air samples collected in the Nagoya urban area by high-volume samplers for a 24-h duration. EC and OC comprised about 12 and 15% of the total suspended particulate mass, respectively. It was found that organic aerosols and EC are major components of Nagoya urban aerosols. The concentration ratio of total carbon (TC) to EC showed little seasonal dependence. The TC to EC ratio did not change under the wide photochemical activity conditions indicated by the oxidant level, while a good correlation was obtained between the concentration of OC and that of carbon monoxide, an indicator of primary combustion products. These results suggest, with respect to the origin of organic aerosols in the Nagoya urban area, that primary organic aerosols are the principal contributor to organic aerosols throughout the year, and that secondary organic aerosols hardly contribute to the total organic aerosol mass. © 1990, American Chemical Society. All rights reserved.