Joint aerobic biodegradation of synthetic and natural textile microfibers and laundry surfactants Ríos Ruiz, Francisco Tapia Navarro, Cristina Martínez Gallegos, Juan Francisco Lechuga Villena, Manuela María Fernández Serrano, Mercedes Microfibers Aerobic biodegradation Surfactants This work has received the financial support provided by the University of Granada, by the Consejería de Universidad, Investigación e Innovación of the Andalusian Government and by the European Regional Development Fund (ERDF) “A way of making Europe” with the research projects PPJIA2022-27 and C.ING.122.UGR23. PFI-Santander 2023 program for funding her research scholarship at the University of Granada. Microfibers (MFs) represent one of the most prominent sources of microplastics in aquatic environments, primarily released during textile washing alongside surfactants found in laundry detergents. This study aimed to investigate the biodegradability of natural (cotton) and synthetic (polyester) MFs individually and in combination with two surfactants: sodium lauryl sulfate (SLS, anionic) and polyoxyethylene glycerol ester (PGE-OE6, nonionic). Using the OECD 301F test, the research assessed biodegradation patterns and environmental interactions. Biodegradation profiles have been fitted to a pseudo first-order kinetic model and to a logistic kinetic model. Results showed that cotton MFs were partially biodegradable, achieving a 74.9% mineralization, while polyester MFs exhibited no biodegradability. Importantly, when combined with surfactants, the biodegradation of SLS was inhibited by polyester MFs, but cotton MFs enhanced SLS mineralization. Conversely, the combination of cotton MFs with PGE-OE6 slowed the biodegradation of both the surfactant and the MFs, delaying the onset of cotton degradation. However, polyester MFs’ biodegradability remained unaffected by either surfactant. These findings emphasize the need for more comprehensive assessments of how MFs and surfactants interact in real-world environmental matrices, as these interactions can influence their persistence and ecological impact. The study highlights the scientific importance of understanding pollutant interactions to develop more effective environmental monitoring and mitigation strategies. 2025-12-19T09:52:33Z 2025-12-19T09:52:33Z 2024-11 journal article Published version: Ríos F., Tapia-Navarro C., Martínez-Gallegos J.F., Lechuga Villena M.M., Fernández-Serrano M. Joint aerobic biodegradation of synthetic and natural textile microfibers and laundry surfactants. J Hazard Mater. 2025 Jan 15;482:136619. doi: 10.1016/j.jhazmat.2024.136619 0304-3894 1873-3336 https://hdl.handle.net/10481/108994 doi.org/10.1016/j.jhazmat.2024.136619 eng embargoed access Elsevier