황사 에피소드 발생시 대기먼지의 농도 특성과 인체 영향

Abstract

The Asian dust storms which originated in the deserts of Mongolia and China transported particles to Korea and led to a high concentration of atmospheric particulate matters (PM) of more than <TEX>$1000{\mu}g/m^3$</TEX> throughout the country in the spring, of 2007. Public concern, in Korea, about the possible adverse effects of these dust events has increased, as these dust storms can contain various air pollutants emitted from heavily industrialized eastern China. The objectives of this study were to understand the concentration characteristics of PM as a function of particle size between the Asian dust storm episodes and non-Asian dust period and to consider the mass size distribution of PM in the Asian dust storms and their water soluble ion species on the potential, possible effects on deposition levels in the three regions (nasopharyngeal, tracheobronchial, and alveolar) of the human respiratory system. The size distribution of PM mass concentration during the Asian dust storms showed a peak in the coarse particle region due to the long-range transport of soil particles from the deserts of Mongolia and China, which was identified by HYSPLIT-4 model for backward trajectory analysis of air arriving in the sampling site of Iksan. During the non-Asian dust period, there were two different types in PM size distribution: bimodal distribution when low concentrations of <TEX>$PM_{2.5}$</TEX> were observed, while unimodal distribution having a peak in fine particle region when high concentrations of <TEX>$PM_{2.5}$</TEX> were showed. This unimodal distribution with high concentrations of fine particulate and secondary air pollutants such as <TEX>${SO_4}^{2-}$</TEX>, <TEX>${NO_3}^-$</TEX>, <TEX>${NH_4}^+$</TEX> was found to be due to the long-range transport of air pollutants from industrialized eastern China. During the Asian dust storms, the mean concentrations of PM that can be deposited in the nasopharyngeal, tracheobronchial, and alveolar region were <TEX>$128.8{\mu}g/m^3$</TEX>, <TEX>$216.5{\mu}g/m^3$</TEX>, and <TEX>$89.6{\mu}g/m^3$</TEX>, respectively. During the non-Asian dust period, the mean concentrations of PM that can be deposited in the nasopharyngeal, tracheobronchial, and alveolar region were <TEX>$8.4{\mu}g/m^3$</TEX>, <TEX>$9.5{\mu}g/m^3$</TEX> and <TEX>$38.5{\mu}g/m^3$</TEX>, respectively.