中国の異なる砂漠地域でバックグラウンドアジアンダスト(黄砂)を計4検体採集した。黄土高原の黄砂の比表面積と全細孔容積はいずれも他の3地域(タクラマカン,トングリ,ホルチン)の黄砂より大きかったが,平均細孔径に大きな違いがなかった。9種の水溶性イオンと15種の元素を分析したところ,4地域の黄砂に組成的な違いが認められた。構築した曝露チャンバーと多環芳香族炭化水素(PAH)酸化体分析計を用いて評価した結果,光及び反応性ガス(NO2/SO2/O3)の有無に因らず,どの地域の黄砂でもPAHを吸着し,さらにPAHをより毒性の強いニトロ体,キノン体への変質を促進する触媒的な作用を有することを明らかにした。
Total four background Asian dust (Kosa) were collected at different desert regions of China. The specific surface area and the total pore volume of the Kosa collected at Huangtu plateau were larger than those at other regions (Taklimakan, Tengger and Horqin). But no significant difference in the average pore size was found among the four Kosas. The compositional differences of analyzed nine water-soluble ions and fifteen elements were observed among the four Kosas. We found that 2 - 4 rings polycyclic aromatic hydrocarbons (PAHs) can be adsorbed by the every Kosa in the conditions of presence or absence of light and reactive gases (NO2/SO2/O3) by using our exposure chamber. We also found that Kosa has catalysis to promote the degeneration reaction of PAHs to their nitro- and/or quinine-derivatives having strong toxicity.