{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,8]],"date-time":"2026-04-08T04:26:25Z","timestamp":1775622385364,"version":"3.50.1"},"reference-count":33,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2024,11,10]],"date-time":"2024-11-10T00:00:00Z","timestamp":1731196800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Water"],"abstract":"<jats:p>Plastics are vital for society, but their usage has grown exponentially and contributes to the growth of pollution worldwide. The World Health Organization, WHO, already reported that microplastics (MPs) are found everywhere, in waste and fresh water, and in the air and soil. Regarding water effluents, waste-water treatment plants only minimize the problem, trapping only larger size particles. In contrast, smaller ones remain in oxidation ponds or sewage sludges, or are even released to aquifers environment. Classic procedures for MPs detection are still quite laborious, and are usually conducted off-line, involving several steps and expensive equipment. Electrical Impedance Spectroscopy, EIS, is a technique that allows the analysis of a system\u2019s electrical response, yielding helpful information about its domain-dependent on physical-chemical properties. Due to the superficial electronegativity of MPs\u2019 particles, EIS may allow to attain the purpose of the present work: to provide a fast and reliable method to detect\/estimate MPs\u2019 concentration in water effluents. Among the most common microplastics are Polyethylene, PE, and Polyvinyl Chloride, PVC. Using the developed setup and experimental data collection methodology, the authors could differentiate between MPs\u2019 suspensions containing the same concentration of the different evaluated MPs, PVC and PE, and assess PVC concentration variation, in the interval between 0.03 to 0.5 g (w\/w), with an error, estimated based on the obtained impedance modulus, around or below 3% for the entire stimulus signal frequency range (from 100 Hz to 40 MHz) for the PVC particles.<\/jats:p>","DOI":"10.3390\/w16223228","type":"journal-article","created":{"date-parts":[[2024,11,11]],"date-time":"2024-11-11T08:46:54Z","timestamp":1731314814000},"page":"3228","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Measuring Microplastic Concentrations in Water by Electrical Impedance Spectroscopy"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-3683-8066","authenticated-orcid":false,"given":"Diogo","family":"Gomes","sequence":"first","affiliation":[{"name":"CEMMPRE\u2014Electrical and Computer Engineering Department, University of Coimbra, FCTUC, Polo 2, Pinhal de Marrocos, 3030-290 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0625-5675","authenticated-orcid":false,"given":"Solange","family":"Magalh\u00e3es","sequence":"additional","affiliation":[{"name":"CERES, Department of Chemical Engineering, University of Coimbra, 3030-790 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6084-4553","authenticated-orcid":false,"given":"Maria Gra\u00e7a","family":"Rasteiro","sequence":"additional","affiliation":[{"name":"CERES, Department of Chemical Engineering, University of Coimbra, 3030-790 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5539-9766","authenticated-orcid":false,"given":"Pedro","family":"Faia","sequence":"additional","affiliation":[{"name":"CEMMPRE\u2014Electrical and Computer Engineering Department, University of Coimbra, FCTUC, Polo 2, Pinhal de Marrocos, 3030-290 Coimbra, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2024,11,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1045","DOI":"10.1016\/j.envpol.2016.08.056","article-title":"Microplastic Pollution Is Widely Detected in US Municipal Wastewater Treatment Plant Effluent","volume":"218","author":"Mason","year":"2016","journal-title":"Environ. 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