{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T04:54:30Z","timestamp":1790916870160,"version":"4.1.0"},"reference-count":55,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T00:00:00Z","timestamp":1790726400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union","award":["IMDEEA\/202\/23"],"award-info":[{"award-number":["IMDEEA\/202\/23"]}],"id":[{"id":"https:\/\/ror.org\/019w4f821","id-type":"ROR","asserted-by":"crossref"}]},{"award":["IMDEEA\/202\/23"],"award-info":[{"award-number":["IMDEEA\/202\/23"]}],"id":[{"id":"https:\/\/ror.org\/019w4f821","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>While various methodologies have been used to evaluate leather biodegradability, limited data exist regarding their respective strengths, limitations and complementarity, especially for finished leathers produced using chrome-free tanning systems. Consequently, this work assesses the biodegradation of eight commercial eco-friendly tanned finished leathers (phenolic-, zeolite-, aluminium- and titanium-based treatments) using two standardised laboratory approaches, ISO 14855-1:2012 (controlled composting) and ISO 20136:2020 (liquid-phase biodegradation), together with physicochemical characterisation and phytotoxicity\/ecotoxicity endpoints. The results showed that biodegradation generally occurred faster under ISO 20136:2020 conditions, mainly because this assay uses ground leather shavings and an aqueous, well-mixed medium, whereas ISO 14855-1:2012 evaluates mineralisation of larger leather pieces in a compost matrix. Phenolic- and titanium-tanned leathers showed consistently high biodegradation in both assays, whereas the aluminium-tanned leather biodegraded efficiently under ISO 14855-1:2012 but showed limited biodegradation under ISO 20136:2020, highlighting that assay conditions can reveal constraints related to the complete material architecture, collagen stabilisation, effective accessibility and method-specific exposure conditions rather than to a single leaching mechanism. Phytotoxicity and ecotoxicity assessments indicated low environmental impact of the degradation products under the tested conditions. Overall, the combined use of both standards provides a more comprehensive and industrially useful framework for assessing the end-of-life behaviour of finished leathers than either method alone.<\/jats:p>","DOI":"10.3390\/polym18192389","type":"journal-article","created":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T09:25:42Z","timestamp":1790760342000},"page":"2389","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Biodegradability of Chromium-Free Finished Leather Through ISO 14855-1:2012 and ISO 20136:2020: A Multi-Faceted Analytical Approach"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2085-1211","authenticated-orcid":false,"given":"Alberto","family":"Vico","sequence":"first","affiliation":[{"name":"Footwear Technological Institute (INESCOP), C\/Alemania 102\u2014Pol\u00edgono Campo Alto, 03600 Elda, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3114-2103","authenticated-orcid":false,"given":"Mar\u00eda I.","family":"Maestre-L\u00f3pez","sequence":"additional","affiliation":[{"name":"Footwear Technological Institute (INESCOP), C\/Alemania 102\u2014Pol\u00edgono Campo Alto, 03600 Elda, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6524-1639","authenticated-orcid":false,"given":"Jose Miguel","family":"Carot-Sierra","sequence":"additional","affiliation":[{"name":"Department of Applied Statistics, Operational Research, and Quality, Universitat Polit\u00e8cnica de Val\u00e8ncia, Camino de Vera s\/n, 46022 Valencia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Irene","family":"Lifante-Martinez","sequence":"additional","affiliation":[{"name":"Footwear Technological Institute (INESCOP), C\/Alemania 102\u2014Pol\u00edgono Campo Alto, 03600 Elda, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1490-7514","authenticated-orcid":false,"given":"Elena","family":"Orgil\u00e9s-Calpena","sequence":"additional","affiliation":[{"name":"Footwear Technological Institute (INESCOP), C\/Alemania 102\u2014Pol\u00edgono Campo Alto, 03600 Elda, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9840-9784","authenticated-orcid":false,"given":"Guillermo","family":"Grindlay","sequence":"additional","affiliation":[{"name":"Department of Analytical Chemistry, Nutrition, and Food Sciences, University of Alicante, Crta\\ San Vicente del Raspeig, s\/n, 03080 San Vicente del Raspeig, Alicante, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9348-4806","authenticated-orcid":false,"given":"Marcelo","family":"Bertazzo","sequence":"additional","affiliation":[{"name":"Footwear Technological Institute (INESCOP), C\/Alemania 102\u2014Pol\u00edgono Campo Alto, 03600 Elda, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,30]]},"reference":[{"key":"ref_1","unstructured":"George, G. 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