都市域のエアロゾルを用いた光照射後の酸化能評価

抄録

We investigated that aerosols affected oxidation ability in the body by measuring the oxidative potential (OP) and reactive oxygen species (ROS) of aerosols collected in Tokyo before and after aging accompanied by photodegradation and photooxidation. After irradiating the aerosol with solar simulator, the chemical composition was extracted using water or surrogate lung fluid (SLF). Each solution was used for dithiothreitol (DTT) assay to investigate oxidation potential (OP_DTT) and ROS measurement. The ROS in water after the light irradiation (ALI) decreased to less than half of that before the light irradiation (BLI). On the other hand, OP_DTT did not change significantly BLI and ALI. This indicates that aerosols have health damage potential due to strong sunlight even if transported over long distances to receptor area from urban area such as Tokyo. In addition, the OP_DTT in the aerosol extracted from the SLF was reduced by 30–60% compared to that of the aerosol extracted with water, and the ROS was reduced more than 90%. This result was found that 90% of the ROS contained in aerosol at Tokyo in summer are composed of reactive oxygen species and peroxides. Furthermore, traditional water extraction DTT assays and reactive oxygen species measurements suggested that oxidation ability in the body is overestimated.