Secondary organic aerosol formation from sequential oxidation of toluene and cresols

Secondary organic aerosol formation from sequential oxidation of toluene and cresols | 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 Secondary organic aerosol formation from sequential oxidation of toluene and cresols Siddharth Iyer, Aliisa Ojala, Aurélien Le Bayon, Avinash Kumar, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7621262/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 Cresols are both primary emissions and products of toluene oxidation in the atmosphere. Their subsequent reactions, along with those of their primary oxidation products methylcatechols, lead to the formation of condensable vapors known as highly oxygenated organic molecules (HOM), which contribute to secondary organic aerosol (SOA) formation. SOA constitutes a significant fraction of atmospheric aerosol, impacting both climate and human health. However, quantifying the contribution of sequential oxidation of toluene to SOA is hampered by an incomplete understanding of how cresols and methylcatechols form condensable vapors. Here, we present flow reactor oxidation experiments demonstrating the rapid (sub-second) formation of HOM with up to 10 oxygen atoms from the three cresol isomers (ortho-, para- and meta-cresol) under atmospheric conditions. Our quantum chemical calculations resolve the underlying autoxidation mechanisms, revealing that initial OH additions to the hydroxyl containing carbon atom lead to geminal diol intermediates that are critical to the rapid formation of HOM from cresols and 3-methylcatechol. Incorporating these autoxidation mechanisms into SOA simulations shows that they account for approximately 38% of toluene SOA composition, and 61% to 88% of ortho-cresol SOA composition. These results indicate strong multi-generational contributions to toluene and cresol SOA, which should be considered when assessing their climate and health impacts. Physical sciences/Chemistry/Environmental chemistry/Atmospheric chemistry Physical sciences/Chemistry/Physical chemistry/Reaction kinetics and dynamics Full Text Additional Declarations There is NO Competing Interest. Supplementary Files SecondaryorganicaerosolformationfromsequentialoxidationoftolueneandcresolsV51.pdf Supplementary information to Secondary organic aerosol formation from sequential oxidation of toluene and cresols 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. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-7621262","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":517701968,"identity":"8ebd577f-116e-4544-9d2c-be999880899d","order_by":0,"name":"Siddharth 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