Microplastic characterization and removal efficiency in wastewater treatment plants with diverse influent sources in Uganda

Microplastic characterization and removal efficiency in wastewater treatment plants with diverse influent sources in 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 Research Article Microplastic characterization and removal efficiency in wastewater treatment plants with diverse influent sources in Uganda Patrick Mulindwa, Florence Nantaba, John Wasswa, Livingstone Mabusi Olira, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8252302/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 Wastewater treatment plants (WWTPs) are significant sources of microplastic (MP) pollution due to widespread plastic use and their limited ability to remove contaminants. This study examined MP levels, characteristics, and removal efficiency in both raw and processed wastewater from Lubigi WWTP, which handles both piped sewage and fecal sludge from private cesspools such as pit latrines and septic tanks, through waste stabilization ponds. The second facility, Bugolobi WWTP, mainly treats domestic wastewater from septic tanks and surface runoff via city drainage, using physical, chemical, and biological treatment methods. Influent MP concentrations were 5,290 ± 605 particles per liter at Lubigi and 14,280 ± 1,057 particles per liter at Bugolobi; effluent levels were 760 ± 69 and 1,160 ± 158 particles per liter, with removal efficiencies of 74 ± 23% and 83 ± 2.8%, respectively. Beads and fragments predominated in influents, whereas films increased in effluents. Larger particles (150–250 µm) were more common in influents, while smaller particles (< 150 µm) mainly appeared in effluents. The primary polymers identified were polyethylene terephthalate (67%) and polyamide (33%). These findings emphasize the need to enhance MP removal processes in Ugandan WWTPs. Wastewater treatment plant microplastic characterization removal efficiency Full Text Additional Declarations No competing interests reported. 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. 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-8252302","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":560712717,"identity":"2da25732-64a0-4365-94b5-8d2a71ba9999","order_by":0,"name":"Patrick Mulindwa","email":"","orcid":"","institution":"Makerere University","correspondingAuthor":false,"prefix":"","firstName":"Patrick","middleName":"","lastName":"Mulindwa","suffix":""},{"id":560712720,"identity":"eec8c953-1f83-48f6-8b58-a5bc6185d18a","order_by":1,"name":"Florence Nantaba","email":"","orcid":"","institution":"Makerere University","correspondingAuthor":false,"prefix":"","firstName":"Florence","middleName":"","lastName":"Nantaba","suffix":""},{"id":560712721,"identity":"1b35b412-feed-4e71-8399-432e24e58db8","order_by":2,"name":"John Wasswa","email":"","orcid":"","institution":"Makerere University","correspondingAuthor":false,"prefix":"","firstName":"John","middleName":"","lastName":"Wasswa","suffix":""},{"id":560712723,"identity":"921af741-2726-4b5e-9f8f-cd2cf7c6c5d3","order_by":3,"name":"Livingstone Mabusi Olira","email":"","orcid":"","institution":"Ministry of Water and Environment","correspondingAuthor":false,"prefix":"","firstName":"Livingstone","middleName":"Mabusi","lastName":"Olira","suffix":""},{"id":560712727,"identity":"522c1b62-168f-4e4e-aa7e-27bb4e4bc33a","order_by":4,"name":"Antonio Jose Expósito","email":"","orcid":"","institution":"University of Bath","correspondingAuthor":false,"prefix":"","firstName":"Antonio","middleName":"Jose","lastName":"Expósito","suffix":""},{"id":560712728,"identity":"7805bc54-9554-4517-abb2-82d0d0f61f9a","order_by":5,"name":"Job S. 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This study examined MP levels, characteristics, and removal efficiency in both raw and processed wastewater from Lubigi WWTP, which handles both piped sewage and fecal sludge from private cesspools such as pit latrines and septic tanks, through waste stabilization ponds. The second facility, Bugolobi WWTP, mainly treats domestic wastewater from septic tanks and surface runoff via city drainage, using physical, chemical, and biological treatment methods. Influent MP concentrations were 5,290\u0026thinsp;\u0026plusmn;\u0026thinsp;605 particles per liter at Lubigi and 14,280\u0026thinsp;\u0026plusmn;\u0026thinsp;1,057 particles per liter at Bugolobi; effluent levels were 760\u0026thinsp;\u0026plusmn;\u0026thinsp;69 and 1,160\u0026thinsp;\u0026plusmn;\u0026thinsp;158 particles per liter, with removal efficiencies of 74\u0026thinsp;\u0026plusmn;\u0026thinsp;23% and 83\u0026thinsp;\u0026plusmn;\u0026thinsp;2.8%, respectively. Beads and fragments predominated in influents, whereas films increased in effluents. Larger particles (150\u0026ndash;250 \u0026micro;m) were more common in influents, while smaller particles (\u0026lt;\u0026thinsp;150 \u0026micro;m) mainly appeared in effluents. The primary polymers identified were polyethylene terephthalate (67%) and polyamide (33%). These findings emphasize the need to enhance MP removal processes in Ugandan WWTPs.\u003c/p\u003e","manuscriptTitle":"Microplastic characterization and removal efficiency in wastewater treatment plants with diverse influent sources in Uganda","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-12-16 10:40:42","doi":"10.21203/rs.3.rs-8252302/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":"e1a44fa9-63cd-4ae3-9610-5dfec259b34b","owner":[],"postedDate":"December 16th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-01-28T09:55:08+00:00","versionOfRecord":[],"versionCreatedAt":"2025-12-16 10:40:42","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8252302","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8252302","identity":"rs-8252302","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}