Understanding the origin of nitroaromatic hydrocarbons in atmospheric particles and their application to new indicators of environmental impact

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K19956
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 63010:Environmental dynamic analysis-related
• Research Institution: Kanazawa University
• Principal Investigator: Ikemori Fumikazu 金沢大学, 環日本海域環境研究センター, 連携研究員 (00773756)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 有機トレーサー / 有機エアロゾル / SOA / PM2.5 / 高時間分解 / 粒形別

Outline of Final Research Achievements

Organic tracer components and nitroaromatic hydrocarbons in PM2.5 collected for 3 hours at event of high photochemical oxidants concentration during spring and summer, were analyzed by GC-MS and LC-MS/MS. The ratio of 3,5-dinitrosalicylic acid and 5-nitrosalicylic acid could potentially be used as a tracer of the progress of aging in the atmosphere. By analyzing NAHCs using size-specific PM samples, our results show that more than 90% of nitrocatechols and 70% of nitrosalicylic acid were concentrated in PM2.5 during the winter season.

Free Research Field

大気環境科学、分析化学、環境化学

Academic Significance and Societal Importance of the Research Achievements

観測例が極めて少ないニトロ芳香族炭化水素について、LC-MS/MSによる高感度分析を確立し、高時間分解観測や粒形別分析を行った。高時間分解観測により、ニトロ芳香族の時間変動を明らかにし、有効なトレーサーが少ない人為起源SOAについて、3,5-ジニトロサリチル酸/5-ニトロサリチル酸比を大気中での変質の進行度を示す指標として提案した点は重要な学術的意義を持つ。日本国内のPM2.5濃度は、国内の環境基準値をほぼ達成しているが、WHOが推奨している目標値よりは以前高濃度であるため、削減対象となりうる人為起源SOAに関する本研究の成果は社会的な意義を持つ。