Ozone promotes aerosol formation from polycyclic aromatic hydrocarbons

Ozone promotes aerosol formation from polycyclic aromatic hydrocarbons | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Ozone promotes aerosol formation from polycyclic aromatic hydrocarbons Avinash Kumar, Mojtaba Bezaatpour, Aliisa Ojala, Prasenjit Seal, and 6 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9486199/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted You are reading this latest preprint version Abstract Secondary organic aerosols (SOA) form through the gas-phase oxidation of organic compounds and constitute a major fraction of atmospheric fine particulate matter influencing air quality, human health, and climate. Among their precursors, polycyclic aromatic hydrocarbons (PAHs) are pervasive pollutants, but the mechanisms by which they yield low volatility vapors remain poorly constrained. The role of ozone (O 3 ), despite its abundance, is generally considered negligible, thus contributing little to low-volatility condensable vapors and to subsequent aerosol formation. Here, we show that O 3 directly participates in and strongly enhances the formation of condensable vapors during hydroxyl radical (OH) initiated oxidation of atmospherically relevant PAHs. Sub-second timescale experiments utilizing isotopically labelled ozone combined with detailed quantum chemical calculations demonstrate the incorporation of O 3 in the early stages of naphthalene oxidation which considerably promotes low-volatility aerosol precursor formation. These results establish an unrecognized pathway in which O 3 accelerates oxidation chemistry of PAHs, in contrast to its traditionally assumed limited reactivity. Incorporating this mechanism into a global chemistry–transport model increases anthropogenic SOA due to only naphthalene by up to 7%, indicating that current models significantly underestimate aerosol formation and highlight the need to reassess the role of ozone in atmospheric oxidation chemistry. Physical sciences/Chemistry/Environmental chemistry/Atmospheric chemistry Physical sciences/Chemistry/Physical chemistry Full Text Additional Declarations There is NO Competing Interest. Supplementary Files SupplementaryInformation.docx Supplementary Information Cite Share Download PDF Status: Under Review Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9486199","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":631672807,"identity":"fdf3c44b-79ff-43dd-b07c-f91e1c5b62a1","order_by":0,"name":"Avinash 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