Acidic Aerosol in Urban Air

Abstract

The distributions and chemical compositions of acidic aerosol in OSAKA City were investigated. Samples were collected at five sites in OSAKA City during June to September in 1979. Acidic aerosol was determined by acid-base titration method and then sulfate ion was determined by barium chloride turbidimetry, nitrate ion by xylenol method and chloride ion by mercury thiocyanate method respectively. The concentrations of acidic aerosol at five sites were ranging from 7.7μg/m³ to 10.0μg/m³, but mean concentration of residential area was slightly higher than that of industrial area.
When acidic aerosol concentration were compaired with other strong acidic ions, SO₄^2-, NO₃^- and Clconcentration, it was shown significant correlations between acidic aerosol and SO₄^2-. The sum of each ion equivalents (sulfate ion+ nitrate ion+chloride ion) showed good correlation with the acidic aerosol equivalent during whole periods.