20.500.12556/DiRROS-17269 UV light causes structural changes in microplastics exposed in bio-solids Bio-solids (biological sludge) from wastewater treatment plants are a significant source of the emission of microplastics (MPs) into the environment. Weakening the structure of MPs before they enter the environment may accelerate their degradation and reduce the environmental exposure time. Therefore, we studied the effect of UV-A and UV-C, applied at 70 °C, on three types of MPs, polypropylene (PP), polyethylene (PE), and polyethylene terephthalate (PET), that are commonly found in sewage sludge, using three shapes (fibers, lines, granules). The MPs were exposed to UV radiation in bio-solid suspensions, and to air and water as control. The structural changes in and degradation of the MPs were investigated using Attenuated Total Reflectance–Fourier Transform Infrared Spectrometry (ATR-FTIR) and surface morphology was performed with SEM analysis. UV exposure led to the emergence of carbonyl and hydroxyl groups in all of the PP samples. In PE and PET, these groups were formed only in the bio-solid suspensions. The presence of carbonyl and hydroxyl groups increased with an increasing exposure time. Overall, UV radiation had the greatest impact on the MPs in the bio-solids suspension. Due to the surface-to-volume ratio of the tested samples, which influences the degradation rate, the fibers were more degraded than the other two plastic shapes. UV-A was slightly more effective at degrading the MPs than UV-C. These findings show that ultraviolet radiation in combination with an elevated temperature affects the structure of polymers in wastewater bio-solids, which can accelerate their degradation. microplastics degradation hydroxyl carbonyl ultraviolet light mikroplastika degradacija hidroksil karbonil ultravijolična svetloba true false true Molecular Diversity Preservation International Angleški jezik Slovenski jezik © 2023 by the authors. Licensee MDPI, Basel, Switzerland. Neznano 2023-11-14 09:46:42 2023-11-14 09:46:42 2023-11-15 03:36:04 0000-00-00 00:00:00 2023 0 0 Nasl. z nasl. zaslona; Opis vira z dne 9. 11. 2023; str. 1-16 iss. 21, [article no.] 4322 Vol. 15 2023 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 2023-11-04 54 2073-4360 10.3390/polym15214322 171474691 https://www.mdpi.com/2073-4360/15/21/4322 1 f3c08596-82c1-11ee-9ccb-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=23452 RAZ_Alavian_Petroody_S._S._2023.pdf RAZ_Alavian_Petroody_S._S._2023.pdf 1 48B58422006BDB640CF05640FFF3AE89 0a19a0c5ff70b0a53215c9cba5d668bb0bdbfdf94b6033bf11b3026da1fc0caa a8c9b6b9-82cf-11ee-9ccb-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=23457 Zavod za gradbeništvo Slovenije 0 0 0