著者

佐藤 圭 田中 友里愛 李 紅 小川 志保 畠山 史郎

出版者

一般社団法人日本地球化学会

雑誌

地球化学 (ISSN:03864073)

巻号頁・発行日

vol.41, no.4, pp.145-153, 2007

参考文献数

26

被引用文献数

2

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To study long-range transport of organic aerosols from East Asian countries to the East China Sea, 3- to 7-ring parental polycyclic aromatic hydrocarbons (PAHs) in aerosols collected at Cape Hedo, Okinawa, Japan (128.3°E, 26.9°N) during 2005-2006 were analyzed by high performance liquid chromatography. The total PAH concentrations were 0.00-16.0 (av. 1.22) ng m^-3 during the entire period. The seasonal average of total PAH concentration increased between winter and spring and decreased in summer. It is interpreted that the pollutants are transported to Cape Hedo by the monsoons from the Asian Continent between winter and spring, whereas oceanic air mass is transported by the monsoons from the Pacific in summer. The benzo[a]pyrene to benzo[e]pyrene ratios were 0.23-0.98 (av. 0.48) in winter and were lower than that measured in East Asian cities, showing that PAHs observed at Cape Hedo are aged by the photochemical reactions proceeding during long-range transport. The average total PAH level measured at Cape Hedo was only 1/10-1/20 of those measured in Japanese cities, but a total PAH level comparable with the average levels in Japanese cities was recorded during a long-range transport event in March, 2006.