Evaluation of size distribution and toxicity of atmospheric polycyclic aromatic hydrocarbon quinones generating reactive oxygen species

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K11676
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 64010:Environmental load and risk assessment-related
• Research Institution: Nagasaki University (2020-2021); Kanazawa University (2018-2019)
• Principal Investigator: Toriba Akira 長崎大学, 医歯薬学総合研究科(薬学系), 教授 (50313680)
• Co-Investigator(Kenkyū-buntansha): 古内 正美 金沢大学, 地球社会基盤学系, 教授 (70165463) ; 唐 寧 金沢大学, 環日本海域環境研究センター, 教授 (90372490)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: 多環芳香族炭化水素 / 大気汚染 / 粒子状物質 / ナノ粒子 / 粒径分布 / 活性酸素 / 酸化ストレス

Outline of Final Research Achievements

Nanoparticles (PM0.1) with a particle size smaller than 0.1 μm were collected at two sites in Japan, and the particle size distribution and sources of polycyclic aromatic hydrocarbon quinones (PAHQs) were analyzed. The results showed that the highest concentrations of PAHQ were distributed in nanoparticles, indicating that PAHQ exposure via nanoparticles may really occur. Secondary formation in the atmosphere and automobile emissions were found to be the major sources of PAHQ. Furthermore, the dithiothreitol (DTT) assay was carried out to determine the ability of generating reactive oxygen species (ROS) of each particle size fraction. The results showed that the smaller particle size had the higher the ROS production ability, and the contribution of PAHQ to it was about 10%, suggesting that the toxicity of nanoparticles may be stronger than that of larger particle size fractions.

Free Research Field

環境分析化学

Academic Significance and Societal Importance of the Research Achievements

活性酸素（ROS）を生成して循環器疾患やアレルギー疾患，喘息等を増悪させる可能性がある多環芳香族炭化水素キノン（PAHQ）類は，大気汚染実態が不明な有機汚染物質であり，微量でも急性影響を示す可能性がある。本研究により，都市大気におけるPAHQのナノ粒子を含む粒径分布，環境動態や発生源，各粒径ごとのROS産生毒性に対する寄与度が初めて明らかとなり，粒径ごとのPAHQ濃度とROS産生に関する毒性との関係が明確になった。得られた成果は健康影響の観点でPM2.5に含まれるより微細な粒子（ナノ粒子）の健康影響の議論や，環境基準などによる規制の必要性に関する判断材料に成り得る。