Health Implications and Risk Assessment of Gestational Exposure to Polycyclic Aromatic Hydrocarbons in Mbarara, Uganda

Health Implications and Risk Assessment of Gestational Exposure to Polycyclic Aromatic Hydrocarbons in Mbarara, Uganda | 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 Health Implications and Risk Assessment of Gestational Exposure to Polycyclic Aromatic Hydrocarbons in Mbarara, Uganda Nicodemus Niwamanya, Godswill J. Udom, Omoirri M. Aziakpono, Nita-wills G. Udom, and 10 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7623027/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract This study examined health risks and outcomes associated with polycyclic aromatic hydrocarbon (PAH) exposure among pregnant women in Mbarara, Uganda. Thirty-two women in their third trimester were recruited from Mbarara Regional Referral Hospital, and maternal blood samples were analysed for PAHs using Gas Chromatography–Mass Spectrometry. Risks were evaluated using the U.S. EPA models and Monte Carlo simulations (MCS). Multiple PAHs were detected, with fluorene (16.38 ± 0.31 mg/L) and chrysene (5.51 ± 4.15 mg/L) showing the highest concentrations. Regression and Spearman correlation analyses revealed significant associations between certain maternal PAH concentrations and adverse outcomes, notably low birth weight and postpartum haemorrhage. Hazard indices exceeded 1, while benzo[a]pyrene toxic and mutagenic equivalents and incremental lifetime cancer risk (ILCR; 1.3×10⁰; 3.19×10⁻¹) surpassed regulatory thresholds, indicating considerable non-cancer and cancer risks. The MCS ILCR estimates further suggested that, in a population of 10 pregnant women, about three could develop cancer from long-term PAH exposure. These findings highlight the urgency for public health actions and policy reforms to reduce PAH exposure among pregnant women in Mbarara, as well as the necessity for further research to evaluate long-term developmental impacts on children exposed in utero . Biological sciences/Cancer Earth and environmental sciences/Environmental sciences Health sciences/Medical research Health sciences/Risk factors Prenatal exposure PAH concentrations in maternal blood adverse health outcomes risk assessment Monte Carlo simulation environmental exposure Full Text Additional Declarations No competing interests reported. Supplementary Files PAHMRRHSupplementals.docx Cite Share Download PDF Status: Posted 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. 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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-7623027","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":524829562,"identity":"278777c9-5208-47ea-9344-bb4ee2b5e9bb","order_by":0,"name":"Nicodemus Niwamanya","email":"","orcid":"","institution":"Kampala International University","correspondingAuthor":false,"prefix":"","firstName":"Nicodemus","middleName":"","lastName":"Niwamanya","suffix":""},{"id":524829565,"identity":"e7f7f21f-3887-4324-9e3a-aef414e092df","order_by":1,"name":"Godswill J. 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Uganda","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Prenatal exposure, PAH concentrations in maternal blood, adverse health outcomes, risk assessment, Monte Carlo simulation, environmental exposure","lastPublishedDoi":"10.21203/rs.3.rs-7623027/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7623027/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis study examined health risks and outcomes associated with polycyclic aromatic hydrocarbon (PAH) exposure among pregnant women in Mbarara, Uganda. Thirty-two women in their third trimester were recruited from Mbarara Regional Referral Hospital, and maternal blood samples were analysed for PAHs using Gas Chromatography\u0026ndash;Mass Spectrometry. Risks were evaluated using the U.S. EPA models and Monte Carlo simulations (MCS). Multiple PAHs were detected, with fluorene (16.38\u0026thinsp;\u0026plusmn;\u0026thinsp;0.31 mg/L) and chrysene (5.51\u0026thinsp;\u0026plusmn;\u0026thinsp;4.15 mg/L) showing the highest concentrations. Regression and Spearman correlation analyses revealed significant associations between certain maternal PAH concentrations and adverse outcomes, notably low birth weight and postpartum haemorrhage. Hazard indices exceeded 1, while benzo[a]pyrene toxic and mutagenic equivalents and incremental lifetime cancer risk (ILCR; 1.3\u0026times;10⁰; 3.19\u0026times;10⁻\u0026sup1;) surpassed regulatory thresholds, indicating considerable non-cancer and cancer risks. The MCS ILCR estimates further suggested that, in a population of 10 pregnant women, about three could develop cancer from long-term PAH exposure. These findings highlight the urgency for public health actions and policy reforms to reduce PAH exposure among pregnant women in Mbarara, as well as the necessity for further research to evaluate long-term developmental impacts on children exposed \u003cem\u003ein utero\u003c/em\u003e.\u003c/p\u003e","manuscriptTitle":"Health Implications and Risk Assessment of Gestational Exposure to Polycyclic Aromatic Hydrocarbons in Mbarara, Uganda","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-07 04:03:30","doi":"10.21203/rs.3.rs-7623027/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"7d625cc4-d83c-401e-85f0-466e984f447f","owner":[],"postedDate":"October 7th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":55781975,"name":"Biological sciences/Cancer"},{"id":55781976,"name":"Earth and environmental sciences/Environmental sciences"},{"id":55781977,"name":"Health sciences/Medical research"},{"id":55781979,"name":"Health sciences/Risk factors"}],"tags":[],"updatedAt":"2025-10-24T05:23:35+00:00","versionOfRecord":[],"versionCreatedAt":"2025-10-07 04:03:30","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7623027","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7623027","identity":"rs-7623027","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}