Multidisciplinary Analysis of Airborne Particle Surface Area as a New Indicator of Adverse Health Effect of PM2.5

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K19856
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 63:Environmental analyses and evaluation and related fields
• Research Institution: Keio University
• Principal Investigator: Okuda Tomoaki 慶應義塾大学, 理工学部(矢上), 教授 (30348809)
• Co-Investigator(Kenkyū-buntansha): 岩田 歩 慶應義塾大学, 理工学部(矢上), 助教 (30827340)
• Project Period (FY): 2018-06-29 – 2022-03-31
• Keywords: 環境分析 / 大気汚染防止・浄化 / 環境質定量化・予測 / エアロゾル / 粒子状物質 / 表面積 / 拡散荷電法 / 肺沈着表面積

Outline of Final Research Achievements

This study was conducted to determine what physical and chemical particle characteristics are related to the index of toxicity of atmospheric particles. Field surveys were conducted at two sites in Japan with different features (Yokohama, Kanagawa Prefecture: urban area, and Suzu, Ishikawa Prefecture: non-urban area). In laboratory experiments, a clear correlation was found between DTT oxidation capacity and particle surface area. On the other hand, the results of the field observations showed that the DTT oxidation capacity per unit particle mass did not show a clear correlation with the surface area of atmospheric particles relative to particle concentration at any of the sites, but was highly correlated with several specific chemical components. This indicates that the DTT oxidation capacity of atmospheric particles can generally be explained by their chemical properties.

Free Research Field

環境化学、大気科学、エアロゾル工学

Academic Significance and Societal Importance of the Research Achievements

実環境大気粒子の有害性が粒子の物理的特性・化学的特性のどちらに依存するのか、を知ることは重要であるため、本研究を進めた。特徴の異なる日本の2地点においてフィールド調査を行い、化学特性に関して、K, Mn, Pb, アンモニウムイオン, 硫酸イオン, 熱分解性有機炭素などの特定の化学成分とDTT酸化能との関連性が明らかになった。室内実験においてはDTT酸化能と粒子表面積の間に明確な相関性が見られた一方で、実環境大気観測の結果からは、実環境大気粒子のDTT酸化能は、物理的特性よりは概ね化学的特性によって説明可能であり、またその変動に寄与する化学成分の質量により推定可能であることが明らかとなった。