Abstract
Airborne suspended particulates were collected at Shinchon by a high volume cascade impactor from Sep. 1990 to Aug. 1991. Organic matter was extracted from particulates and fractionated by liquid-liquid extraction and thin layer chromatography. Substances in the PAHs and nitroarenes'subfraction of neutral fraction were determined by capillary gas chromatography. Based on unit risk estimates by multi-stage model of benzo[a]pyrene and the results of exposure estimates, cancer risk was assessed. The annual average concentration of total suspended particulates was 201.77g/$m^3$. The percentage of fine particulates was 57.40. The concentration of total suspended particulates showed seasonal variations and was high in winter and spring. The average concentration of extractable organic matter was 8.12g/$m^3$. In all, 21 PAHs were identified and quantified. The annual concentration of fluoranthene was 2.38ng/$m^3$, and that was the highest value of all PAHs. A carcinogenic compound, benzo[a]pyrene, was at a concentration of 1.84ng/$m^3$. All the 10 nitroarenes were also identified and quantified. The major nitroarene in the Shinchon area was 2,7-dinitrofluorene. The annual concentration of 1-nitropyrene was 1.56ng/$m^3$. Concentrations of PAHs and nitroarenes were high in winter and low in summer. The life time excess risk estimates of benzo[a]pyrene was calculated as 0.96 persons/a million population in this experiment. In the rank of relative potenties, carcinogenic effects of the other PAHs were calculated as 0.004-0.108 persons/a million population.
