Okuda, Tomoaki

写真a

Affiliation

Faculty of Science and Technology, Department of Applied Chemistry ( Yagami )

Position

Professor

E-mail Address

E-mail address

Related Websites

External Links
Scopus Paper Info  
Paper Count: 114 Citation Count: 3504 h-index: 31

Click to view the Scopus page. The data was downloaded from Scopus API in June 28, 2026, via http://api.elsevier.com and http://www.scopus.com .

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Profile Summary 【 Display / hide 】

  • Study on physical and chemical characteristics of atmospheric particulate matter (PM2.5) associated with health hazard

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Career 【 Display / hide 】

  • 2020.04
    -
    Present

    理工学部応用化学科, 大学教授

  • 2023.04
    -
    Present

    理工学研究科開放環境科学専攻環境エネルギー科学専修, 専修主任

  • 2024.04
    -
    Present

    理工学部, 企画室会議

  • 2025.04
    -
    Present

    理工学部, 学習指導副主任

  • 2015.04
    -
    2020.03

    理工学部応用化学科, 大学准教授

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Academic Background 【 Display / hide 】

  • 1999.04
    -
    2002.03

    Tokyo University of Agriculture and Technology, Graduate School, Division of Agricltural Sciences

    Graduate School, Completed, Doctoral course

  • 1997.04
    -
    1999.03

    Tokyo Metropolitan University, Graduate School, Division of Natural Science, Department of Chemistry

    Graduate School, Completed, Master's course

  • 1993.04
    -
    1997.03

    Tokyo Metropolitan University, Faculty of Science, Department of Chemistry

    University, Graduated

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Academic Degrees 【 Display / hide 】

  • Doctor (Agricultural Science), Tokyo University of Agriculture and Technology, Coursework, 2002.03

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Research Areas 【 Display / hide 】

  • Environmental Science/Agriculture Science / Environmental dynamic analysis (Environmental Dynamic Analysis)

  • Nanotechnology/Materials / Green sustainable chemistry and environmental chemistry (Environmental Chemistry)

  • Natural Science / Space and planetary sciences (Earth Astrohemistry)

  • Manufacturing Technology (Mechanical Engineering, Electrical and Electronic Engineering, Chemical Engineering) / Transport phenomena and unit operations

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Research Keywords 【 Display / hide 】

  • aerosol, PM2.5, fine particulate matter, physical and chemical characteristics, health impacts

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Books 【 Display / hide 】

  • 環境化学

    OKUDA TOMOAKI, 日本有機地球化学会, 2014

    Scope: 日本地球化学会（監修）地球・環境有機分子質量分析マニュアル2014，第１部第５章

  • Aerosol Pollution in China

    OKUDA TOMOAKI, TANAKA SHIGERU, HE KEBIN, MA YONGLIANG, 京都大学学術出版会、京都, 2007

    Scope: 24-32

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Papers 【 Display / hide 】

  • Isolation of Clostridioides difficile from the atmospheric fine particulate matter

    Ishibashi M., Yonogi S., Tani M., Hiura C., Hosokawa D., Matsuta N., Sagisaka Y., Yagi M., Hasei T., Hayashi M., Shiwa Y., Maruyama F., Tanaka D., Okuda T., Maki T., Komano J.

    BMC Microbiology 26 ( 1 )  2026.12

    ISSN  1471-2180

    　View Summary

    Abstract: Clostridioides difficile is a spore−forming, obligate anaerobic bacillus commonly found in soil and the intestinal tracts of animals. It is a major cause of antibiotic−associated diarrhea (AAD) in humans. Our previous study suggested a possible environmental dissemination. To investigate whether atmospheric aerosols contribute to its spread, atmospheric aerosol samples were collected from ten geographic locations in East Asia, and the presence of C. difficile genomic sequences was assessed using 16S rRNA amplicon sequencing. Additionally, atmospheric PM2.5 samples were collected from two sites in Japan, and analyzed by 16S rRNA amplicon sequencing and selective culturing. C. difficile genomic sequences were detected in aerosols from 8 sampling sites, with relative abundances ranging from 0.03% to 9.88% of total prokaryotic reads. From PM2.5 samples, seven C. difficile strains were isolated, and classified into five genotypes. Three genotypes matched low−frequency clinical or environmental strains in Japan (0.1–0.6%), while two were previously unreported. Phylogenetic analysis showed that four genotypes were closely related to strains from North America, Europe, Africa, and Southeast Asia, respectively. These findings are consistent with the possibility that C. difficile may disperse globally via atmospheric aerosols. Successful colonization of C. difficile in the deposited environments likely depends on ecological adaptability.

  • Seasonal Variation in PM<sub>2.5</sub> Composition Modulates Oxidative Stress and Neutrophilic Inflammation with Involvement of TLR4 Signaling

    Wang, D; Zeng, ZR; Nawata, A; Baba, R; Okazaki, R; Okuda, T; Yoshida, Y

    ANTIOXIDANTS 15 ( 1 )  2026.01

  • Variability of submicron ice-nucleating particles at urban and rural sites in Japan related to aerosol chemical components

    Iwata A., Horwitz S.G.M., Kurihara K., Matsuki A., Okuda T.

    Atmospheric Research 327 2026.01

    ISSN  01698095

    　View Summary

    Ice-nucleating particles (INPs) play a pivotal role in cloud formation and precipitation, yet predicting their concentrations remains difficult due to limited understanding of their spatiotemporal variability and characteristics. Therefore, it is important to provide insights into how aerosol properties and meteorological parameters are related to INP concentrations. This study investigated INP concentrations, their heat sensitivity, particle chemical components, and meteorological parameters at urban (Yokohama) and rural (Noto) sites in Japan during Dust and Non-Dust periods. While no single key factor consistently explained INP concentrations, relatively strong associations were observed with factors implying particles such as mineral dust, heat-sensitive biological particles, and Pb-containing particles from coal and waste combustion, with variations depending on site and season. During the Dust period, INP concentrations at both sites were correlated with the mineral indicators (R > 0.57), though INPs above −15 °C remained low at Noto site (R = 0.49). In the Non-Dust period, mineral indicators cannot account for INP levels at either site (R < −0.31). Heat treatment-induced deactivation of INPs above −15 °C in the urban area suggested a close association between biological INPs and mineral particles. Although submicron INPs account for only a small fraction of total INPs at the surface (e.g., < 6.5 % at −12.5 °C), the particle types that contributed to the variability in INP concentrations were nevertheless supported previous qualitative findings. Our findings also highlight the complexity of quantitatively linking environmental factors that vary by region and time to INP concentration variations to characterize aerosol–cloud interactions.

  • Development of a Water-Soluble Filter for Potential Use in the Toxicity Evaluation of Ambient Particulate Matter

    Yang, L; Nishita-Hara, C; Shiraishi, M; Tsubakida, K; Shibata, Y; Jing, WD; Li, D; Yoshimura, K; Kurokawa, N; Hotta, A; Okuda, T

    AEROSOL AND AIR QUALITY RESEARCH 26 ( 1 )  2025.12

    ISSN  1680-8584

  • Numerical analysis of collision mechanism that causes particle tribocharging in dry powder inhaler

    Mitani R., Nor M.A.b.M., Iinuma T., Mori T., Okuda T.

    Asian Journal of Atmospheric Environment 19 ( 1 )  2025.12

    ISSN  19766912

    　View Summary

    Chronic obstructive pulmonary disease (COPD) is induced by inhalation of toxic substances such as cigarettes and air pollution. Dry powder inhalers (DPIs) are the primary treatment for these diseases. However, they have some problems, such as residuals in a capsule caused by electrostatic force before reaching the human lungs. This study investigated the particle tribocharging mechanism in a DPI using a tandem differential mobility analyzer (TDMA) and a combined discrete element method and computational fluid dynamics (DEM-CFD) approach. In the TDMA experiment, the charging state of the particles changed from negative to positive charge in the DPI device fabricated by the 3D printer. This is because tribocharging is caused by particle–particle collisions and particle–wall collisions. In the numerical simulation, particle–wall collisions occurred more frequently than particle–particle collisions. Therefore, the particle–wall collisions change the charging state of the particle in the DPI device. These results suggest that collisions between particles and walls of the device cause the particles to become charged, leading to a decrease in their deposition in the deeper regions of the lungs. Moreover, the large turbulence kinetic energy of the airflow in the DPI device caused particle–wall collisions because the particles were widely dispersed in the DPI device. These results suggest that optimum turbulence kinetic energy is necessary to reduce particle aggregation and improve the delivery efficiency of DPIs to the human lungs.

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Papers, etc., Registered in KOARA 【 Display / hide 】

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Reviews, Commentaries, etc. 【 Display / hide 】

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Presentations 【 Display / hide 】

  • PM2.5の物理化学特性の解明と曝露実験による生体有害性評価

    奥田知明

    [Domestic presentation]  第88回日本衛生学会 (東京工科大学蒲田キャンパス、東京都大田区) , 

    2018.03
    , 

    Oral presentation (invited, special), 日本衛生学会

  • Development of measurement techniques of physical and chemical characteristics of atmospheric aerosols related to their adverse health effect

    Okuda, T.

    [International presentation]  Frontiers of Atmospheric Aerosol Studies: Toward the Understanding of Their Health and Climatic Effects (Nagoya, Japan) , 

    2018.01
    , 

    Oral presentation (invited, special)

  • Numerical simulation of a parallel plate particle separator for measurement of charging state of PM2.5

    Yonemichi, T., Fukagata, K., Fujioka, K., Okuda, T.

    [International presentation]  9th JSME-KSME Thermal and Fluids Engineering Conference (Okinawa, Japan) , 

    2017.10
    , 

    Poster presentation, JSME

  • PM2.5を集めて測る ～捕集と特性解明の技術～

    奥田知明

    [Domestic presentation]  第7回CSJ化学フェスタ (タワーホール船堀、東京都江戸川区) , 

    2017.10
    , 

    Oral presentation (invited, special), 日本化学会

  • 黄砂・PM2.5の健康乳幼児の目・鼻・呼吸器症状への影響 - エコチル調査追加調査『黄砂と子どもの健康調査（パート２）』より -

    金谷久美子、亀田貴之、大久保綾乃、森育子、増本年男、黒沢洋一、大西一成、奥田知明、中山健夫

    [Domestic presentation]  第58回大気環境学会年会 (兵庫医療大学、兵庫県神戸市) , 

    2017.09
    , 

    Poster presentation, 大気環境学会

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Research Projects of Competitive Funds, etc. 【 Display / hide 】

  • 小型軽量センサによるレゴリス検知および集塵評価技術の開発

    2026.04
    -
    2028.03

    （国研）宇宙航空研究開発機構(JAXA), 第13回研究提案募集・ゲームチェンジ型課題, Joint research, Principal investigator

  • Development of a novel water-soluble filter that expands the possibilities of pathogen testing methods

    2025.06
    -
    2028.03

    挑戦的研究（萌芽）, Principal investigator

  • Establishment of a new environmental chemical analysis method for endotoxin as a key parameter to elucidate the toxicity of aerosol particles

    2024.04
    -
    2027.03

    基盤研究(B), Principal investigator

  • Development of a Health Effect Evaluation System for Particulate Matter Characteristics for the Central Asian Region

    2023.09
    -
    2027.03

    国際共同研究加速基金（海外連携研究）, Principal investigator

  • Development and practical application of a new filter to promote collaboration between the chemical and biological research fields of aerosol toxicity assessment

    2022.06
    -
    2025.03

    MEXT,JSPS, Grant-in-Aid for Scientific Research, 挑戦的研究（萌芽）, Principal investigator

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Intellectual Property Rights, etc. 【 Display / hide 】

  • 微小粒子の捕集装置

    Date applied： 特願2017-132547  2017.07 

    Date announced： 特開2018-023970  2018.02 

    Patent, Joint

  • 自動オープンクロマトグラフィー装置

    Date applied：   2007.07 

    Date announced：   2007.09 

    Date issued： 3135990 

    Utility model, Joint

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Awards 【 Display / hide 】

  • 2015 Asian Young Aerosol Scientist Award

    Tomoaki OKUDA, 2015.06, The Asian Aerosol Research Assembly, Outstanding contribution to aerosol science and technology in Asia

    Type of Award： International academic award (Japan or overseas)

  • 2023 Commendation for Science and Technology by the Minister of Education, Culture, Sports, Science and Technology

    Tomoaki OKUDA, and 4 other members, 2023.04, Ministry of Education, Culture, Sports, Science and Technology , Contributions to the mass-gathering event under the COVID-19 pandemic

    Type of Award： International academic award (Japan or overseas)

  • Academic Award, Japan Society for Atmospheric Environment

    Tomoaki OKUDA, 2025.09, Japan Society for Atmospheric Environment, Experimental Research and Contribution to Society Regarding Atmospheric Environment and Human Health

    Type of Award： Award from Japanese society, conference, symposium, etc.

  • Best Paper Award, Japan Society for Atmospheric Environment

    Tomoaki OKUDA, Masanobu SAKAIDE, Ayumi IWATA, Motoi FUJIWARA, 2020.09, Japan Society for Atmospheric Environment, Investigation of the Characteristics of Particulate Matter Suspended in a Subway Station Platform

    Type of Award： Award from Japanese society, conference, symposium, etc.

  • Incentive Award 2015, Japan Association of Aerosol Science and Technology

    Tomoaki OKUDA, 2015.06, Japan Association of Aerosol Science and Technology, Elucidation of physical and chemical characteristics of atmospheric aerosols related to their adverse health effect

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Courses Taught 【 Display / hide 】

  • FRONTIER OF CHEMISTRY

    2026

  • SHACHU-KYORYOKU PROJECT 1

    2026

  • GRADUATE RESEARCH ON CHEMISTRY, LIFE SCIENCE, AND INFORMATICS 2

    2026

  • GRADUATE RESEARCH ON SCIENCE FOR OPEN AND ENVIRONMENTAL SYSTEMS 1

    2026

  • INDEPENDENT STUDY ON SCIENCE FOR OPEN AND ENVIRONMENTAL SYSTEMS

    2026

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Courses Previously Taught 【 Display / hide 】

  • 自然科学実験（化学）

    Keio University

    2018.04
    -
    2019.03
    , 

    Spring Semester, Laboratory work/practical work/exercise, Within own ｆaculty

  • 大気環境科学

    Keio University

    2018.04
    -
    2019.03
    , 

    Autumn Semester, Lecture

  • 化学B

    Keio University

    2018.04
    -
    2019.03
    , 

    Autumn Semester, Lecture

  • 環境化学２

    Keio University

    2018.04
    -
    2019.03
    , 

    Autumn Semester, Lecture

  • 応用化学実験CD

    Keio University

    2018.04
    -
    2019.03
    , 

    Autumn Semester, Laboratory work/practical work/exercise, Within own ｆaculty

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Memberships in Academic Societies 【 Display / hide 】

  • The Chemical Society of Japan, 

    2015.06
    -
    Present

  • Japan Association of Aerosol Science and Technology, 

    2006.04
    -
    Present

  • The Japan Society for Analytical Chemistry, 

    2004.04
    -
    Present

  • 日本大気化学会, 

    2002.04
    -
    Present

  • Japan Society for Atmospheric Environment, 

    2002.04
    -
    Present

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Committee Experiences 【 Display / hide 】

  • 2025.11
    -
    2026.10

    大学設置・学校法人審議会（大学設置分科会）専門委員, 文部科学省

  • 2023.03
    -
    Present

    南極環境実態把握モニタリング事業検討委員会委員, 環境省

  • 2022.08
    -
    2026.07

    常任理事, 日本エアロゾル学会

  • 2020.09
    -
    Present

    常任理事, 大気環境学会

  • 2020.06
    -
    2021.03

    新型コロナウイルス対策専門家会議委員, 内閣府

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