Crossing barriers – tracking micro- and nanoplastic pathways into the human brain

Crossing barriers – tracking micro- and nanoplastic pathways into the human brain | 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 Crossing barriers – tracking micro- and nanoplastic pathways into the human brain Hans Ludwig, Katrin Biesner, Florian Edbauer, Tobias Meyer, Marija Djukic, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8698660/v2 This work is licensed under a CC BY 4.0 License Status: Posted Version 2 posted You are reading this latest preprint version Show more versions Abstract Nano- and microplastic (NMP) has been detected in human post mortem (PM) brain homogenates. It is still a matter of debate, if NMP can cross brain barriers and reach neurofluids and the brain parenchyma. To track putative pathways, we have investigated in vitro endocytosis of NMP using human stimulated monocytes exposed to plain 1 μm and 100 nm polystyrene beads in vitro by transmission electron microscopy TEM (N=5) and EDX spectroscopy. NMP was localized after 10 min incubation time in endocytic vesicles and adjacent and inside degenerating mitochondria inducing mitophagy and lipofuscin accumulation. To track corresponding in vivo pathways, we have performed TEM of randomly accessed human PM choroid plexus (N=5) and subventricular tissue (N=5) as well as of leukocytes prepared from CSF cell pellets from geriatric patients (N=6). NMP remnants were detected in all autopsy cases (mean 75.6 yrs.) inside endothelia and epithelial cells as well as inside CSF leucocytes, localized adjacent to lipofuscin and Biondi bodies together with Aß fibrils. These preliminary results in a monocyte cell line, postmortem brain tissue and CSF cells localized accumulation of NMP remnants after crossing the barriers between blood and the human brain. Microplastic nanoplastic lipofuscin choroid plexus monocytes CSF glymphatic system TEM ultrastructure EDX spectroscopy Full Text Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted Version 2 posted You are reading this latest preprint version Show more versions 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-8698660","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":581770359,"identity":"fc9e6e7b-0d60-4282-81fe-1dfb606fc898","order_by":0,"name":"Hans Ludwig","email":"data:image/png;base64,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","orcid":"https://orcid.org/0000-0001-8744-9510","institution":"Department of Neuropathology, University Medical Center Göttingen, Robert-Koch-Strasse 40, 37075 Göttingen","correspondingAuthor":true,"prefix":"","firstName":"Hans","middleName":"","lastName":"Ludwig","suffix":""},{"id":581770360,"identity":"2df47199-9478-4d3b-8ec4-877b8f2164f2","order_by":1,"name":"Katrin Biesner","email":"","orcid":"","institution":"Department of Neuropathology, University Medical Center Göttingen, Robert-Koch-Strasse 40, 37075 Göttingen","correspondingAuthor":false,"prefix":"","firstName":"Katrin","middleName":"","lastName":"Biesner","suffix":""},{"id":581770361,"identity":"5fa546e1-c9b3-4635-a42e-0f2aa5c4cc69","order_by":2,"name":"Florian Edbauer","email":"","orcid":"","institution":"Department of Neuropathology, University Medical Center Göttingen, Robert-Koch-Strasse 40, 37075 Göttingen","correspondingAuthor":false,"prefix":"","firstName":"Florian","middleName":"","lastName":"Edbauer","suffix":""},{"id":581770362,"identity":"3b6ca3aa-1bb6-416b-b1da-7e9ad17cf224","order_by":3,"name":"Tobias Meyer","email":"","orcid":"","institution":"Institute of Materials Physics, Georg-August-University Göttingen. 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