Pollution by plastic and microplastic impacts the environment globally. Knowledge on the ageing mechanisms of plastics in natural settings is needed to understand their environmental fate and their reactivity in the ecosystems. Accordingly, the study of ageing processes is gaining focus in the context of the environmental sciences. However, laboratory-based experimental research has typically assessed individual ageing processes, limiting environmental applicability. In this study, we propose a multi-tiered approach to study the environmental ageing of polyethylene plastic fragments focusing on the combined assessment of physical and biological processes in sequence. The ageing protocol included ultraviolet irradiation in air and in a range of water solutions, followed by a biofouling test. Changes in surface characteristics were assessed by Fourier transform infrared spectroscopy, scanning electron microscopy, and water contact angle. UV radiation both in air and water caused a significant increase in the density of oxidized groups (i.e., hydroxyl and carbonyl) on the plastic surface, whereby water solution chemistry influenced the process both by modulating surface oxidation and morphology. Biofouling, too, was a strong determinant of surface alterations, regardless of the prior irradiation treatments. All biofouled samples present (i) specific infrared bands of new surface functional groups (e.g., amides and polysaccharides), (ii) a further increase in hydroxyl and carbonyl groups, (iii) the diffuse presence of algal biofilm on the plastic surface, and (iv) a significant decrease in surface hydrophobicity. This suggests that biological-driven alterations are not affected by the level of physicochemical ageing and may represent, in real settings, the main driver of alteration of both weathered and pristine plastics. This work highlights the potentially pivotal role of biofouling as the main process of plastic ageing, providing useful technical insights for future experimental works. These results also confirm that a multi-tiered laboratory approach permits a realistic simulation of plastic environmental ageing in controlled conditions.

Department of Human and Innovation for the Territory University of Insubria Via Valleggio 11 22100 Como Italy

Department of Science and High Technology University of Insubria Via Valleggio 11 22100 Como Italy

Norwegian Institute for Water Research Økernveien 94 0579 Oslo Norway

RECETOX Masarik University Kamenice 753 5 625 00 Brno Czech Republic

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Abed RMM, Muthukrishnan T, Al Khaburi M, et al. Degradability and biofouling of oxo-biodegradable polyethylene in the planktonic and benthic zones of the Arabian Gulf. Mar Pollut Bull. 2020;150:110639. doi: 10.1016/j.marpolbul.2019.110639. PubMed DOI

Alimi OS, Claveau-Mallet D, Kurusu RS, et al. Weathering pathways and protocols for environmentally relevant microplastics and nanoplastics: what are we missing? J Hazard Mater. 2022;423:126955. doi: 10.1016/j.jhazmat.2021.126955. PubMed DOI

Allan IJ, Samanipour S, Manoli K, et al. Examining the relevance of the microplastic-associated additive fraction in environmental compartments. ACS ES&T Water. 2022;2:405–413. doi: 10.1021/acsestwater.1c00310. DOI

Amaral-Zettler LA, Zettler ER, Mincer TJ, et al. Biofouling impacts on polyethylene density and sinking in coastal waters: a macro/micro tipping point? Water Res. 2021;201:117289. doi: 10.1016/j.watres.2021.117289. PubMed DOI

Arias-Andres M, Kettner MT, Miki T, Grossart H-P. Microplastics: new substrates for heterotrophic activity contribute to altering organic matter cycles in aquatic ecosystems. Sci Total Environ. 2018;635:1152–1159. doi: 10.1016/j.scitotenv.2018.04.199. PubMed DOI

Barnes DKA, Galgani F, Thompson RC, Barlaz M. Accumulation and fragmentation of plastic debris in global environments. Philos Trans R Soc B: Biol Sci. 2009;364:1985–1998. doi: 10.1098/rstb.2008.0205. PubMed DOI PMC

Barros J, Seena S. Plastisphere in freshwaters: an emerging concern. Environ Pollut. 2021;290:118123. doi: 10.1016/j.envpol.2021.118123. PubMed DOI

Bellasi A, Binda G, Boldrocchi G, et al. What are lake beaches made of? An assessment of plastic beach litter on the shores of Como Bay (Italy) Appl Sci. 2022;12:5388. doi: 10.3390/app12115388. DOI

Bellasi A, Binda G, Pozzi A, et al. The extraction of microplastics from sediments: an overview of existing methods and the proposal of a new and green alternative. Chemosphere. 2021;278:130357. doi: 10.1016/j.chemosphere.2021.130357. PubMed DOI

Bellasi A, Binda G, Pozzi A, et al. Microplastic contamination in freshwater environments: a review, focusing on interactions with sediments and benthic organisms. Environments. 2020;7:30. doi: 10.3390/environments7040030. DOI

Bhagat K, Barrios AC, Rajwade K, et al. Aging of microplastics increases their adsorption affinity towards organic contaminants. Chemosphere. 2022;298:134238. doi: 10.1016/j.chemosphere.2022.134238. PubMed DOI

Bhagwat G, O’Connor W, Grainge I, Palanisami T (2021) Understanding the fundamental basis for biofilm formation on plastic surfaces: role of conditioning films. Front Microbiol 12.10.3389/fmicb.2021.687118 PubMed PMC

Binda G, Bellasi A, Spanu D, et al. Evaluating the environmental impacts of personal protective equipment use by the general population during the COVID-19 pandemic: a case study of Lombardy (Northern Italy) Environments. 2021;8:33. doi: 10.3390/environments8040033. DOI

Binda G, Frascoli F, Spanu D et al (2022) Geochemical markers as a tool for the characterization of a multi-layer urban aquifer: the case study of Como (Northern Italy). Water 14.10.3390/w14010124

Binda G, Spanu D, Bettinetti R, et al. Comprehensive comparison of microalgae-derived biochar from different feedstocks: a prospective study for future environmental applications. Algal Res. 2020;52:102103. doi: 10.1016/j.algal.2020.102103. DOI

Binda G, Spanu D, Monticelli D, et al. Unfolding the interaction between microplastics and (trace) elements in water: a critical review. Water Res. 2021;204:117637. doi: 10.1016/j.watres.2021.117637. PubMed DOI

Bond T, Ferrandiz-Mas V, Felipe-Sotelo M, van Sebille E. The occurrence and degradation of aquatic plastic litter based on polymer physicochemical properties: a review. Crit Rev Environ Sci Technol. 2018;48:685–722. doi: 10.1080/10643389.2018.1483155. DOI

Capolupo M, Sørensen L, Jayasena KDR, et al. Chemical composition and ecotoxicity of plastic and car tire rubber leachates to aquatic organisms. Water Res. 2020;169:115270. doi: 10.1016/j.watres.2019.115270. PubMed DOI

Cavaglia J, Schorn-García D, Giussani B, et al. ATR-MIR spectroscopy and multivariate analysis in alcoholic fermentation monitoring and lactic acid bacteria spoilage detection. Food Control. 2020;109:106947. doi: 10.1016/j.foodcont.2019.106947. DOI

Ceschin S, Bellini A, Scalici M. Aquatic plants and ecotoxicological assessment in freshwater ecosystems: a review. Environ Sci Pollut Res. 2021;28:4975–4988. doi: 10.1007/s11356-020-11496-3. PubMed DOI PMC

Chamas A, Moon H, Zheng J, et al. Degradation rates of plastics in the environment. ACS Sustainable Chemistry and Engineering. 2020;8:3494–3511. doi: 10.1021/acssuschemeng.9b06635. DOI

Chaudhary AK, Vijayakumar RP. Effect of chemical treatment on biological degradation of high-density polyethylene (HDPE) Environ Dev Sustain. 2020;22:1093–1104. doi: 10.1007/s10668-018-0236-6. DOI

Chen Q, Wang Q, Zhang C, et al. Aging simulation of thin-film plastics in different environments to examine the formation of microplastic. Water Res. 2021;202:117462. doi: 10.1016/j.watres.2021.117462. PubMed DOI

Cutroneo L, Reboa A, Besio G, et al. Microplastics in seawater: sampling strategies, laboratory methodologies, and identification techniques applied to port environment. Environ Sci Pollut Res. 2020;27:8938–8952. doi: 10.1007/s11356-020-07783-8. PubMed DOI PMC

Danso D, Chow J, Streita WR (2019) Plastics: environmental and biotechnological perspectives on microbial degradation. Appl Environ Microbiol 85.10.1128/AEM.01095-19 PubMed PMC

Davranche M, Veclin C, Pierson-Wickmann A-C, et al. Are nanoplastics able to bind significant amount of metals? The lead example. Environ Pollut. 2019;249:940–948. doi: 10.1016/j.envpol.2019.03.087. PubMed DOI

Delacuvellerie A, Benali S, Cyriaque V, et al. Microbial biofilm composition and polymer degradation of compostable and non-compostable plastics immersed in the marine environment. J Hazard Mater. 2021;419:126526. doi: 10.1016/j.jhazmat.2021.126526. PubMed DOI

Deng H, Fu Q, Li D, et al. Microplastic-associated biofilm in an intensive mariculture pond: temporal dynamics of microbial communities, extracellular polymeric substances and impacts on microplastics properties. J Clean Prod. 2021;319:128774. doi: 10.1016/j.jclepro.2021.128774. DOI

Di Pippo F, Venezia C, Sighicelli M, et al. Microplastic-associated biofilms in lentic Italian ecosystems. Water Res. 2020;187:116429. doi: 10.1016/j.watres.2020.116429. PubMed DOI

Duan J, Bolan N, Li Y, et al. Weathering of microplastics and interaction with other coexisting constituents in terrestrial and aquatic environments. Water Res. 2021;196:117011. doi: 10.1016/j.watres.2021.117011. PubMed DOI

Fairbrother A, Hsueh HC, Kim JH, et al. Temperature and light intensity effects on photodegradation of high-density polyethylene. Polym Degrad Stab. 2019;165:153–160. doi: 10.1016/j.polymdegradstab.2019.05.002. DOI

Fotopoulou KN, Karapanagioti HK. Surface properties of beached plastic pellets. Mar Environ Res. 2012;81:70–77. doi: 10.1016/j.marenvres.2012.08.010. PubMed DOI

Geburtig A, Wachtendorf V, Schmidt A, Goedecke T. Combined impact of UV radiation and nitric acid on HDPE containers during outdoor exposure. Materialpruefung/materials Testing. 2018;60:257–264. doi: 10.3139/120.111148. DOI

Gewert B, Plassmann MM, Macleod M. Pathways for degradation of plastic polymers floating in the marine environment. Environmental Sciences: Processes and Impacts. 2015;17:1513–1521. doi: 10.1039/c5em00207a. PubMed DOI

Gorla G, Mestres M, Boqué R, et al. ATR-MIR spectroscopy to predict commercial milk major components: a comparison between a handheld and a benchtop instrument. Chemom Intell Lab Syst. 2020;200:103995. doi: 10.1016/j.chemolab.2020.103995. DOI

Gurbanov R, Gozen AG, Severcan F. Rapid classification of heavy metal-exposed freshwater bacteria by infrared spectroscopy coupled with chemometrics using supervised method. Spectrochim Acta Part A Mol Biomol Spectrosc. 2018;189:282–290. doi: 10.1016/j.saa.2017.08.038. PubMed DOI

Häder DP, Williamson CE, Wängberg SÅ, et al. Effects of UV radiation on aquatic ecosystems and interactions with other environmental factors. Photochem Photobiol Sci. 2015;14:108–126. doi: 10.1039/c4pp90035a. PubMed DOI

He S, Jia M, Xiang Y et al (2021) Biofilm on microplastics in aqueous environment: physicochemical properties and environmental implications. J Hazard Mater 127286.10.1016/j.jhazmat.2021.127286 PubMed

Helm D, Naumann D. Identification of some bacterial cell components by FT-IR spectroscopy. FEMS Microbiol Lett. 1995;126:75–79. doi: 10.1111/j.1574-6968.1995.tb07393.x. DOI

Huang L, Li L, Dong W, et al. Removal of ammonia by OH radical in aqueous phase. Environ Sci Technol. 2008;42:8070–8075. doi: 10.1021/es8008216. PubMed DOI

Hurley RR, Nizzetto L. Fate and occurrence of micro(nano)plastics in soils: knowledge gaps and possible risks. Current Opinion in Environmental Science and Health. 2018;1:6–11. doi: 10.1016/j.coesh.2017.10.006. DOI

Kalčíková G, Skalar T, Marolt G, Jemec Kokalj A (2020) An environmental concentration of aged microplastics with adsorbed silver significantly affects aquatic organisms. Water Res 175.10.1016/j.watres.2020.115644 PubMed

Kiki C, Qiu Y, Wang Q et al (2022) Induced aging, structural change, and adsorption behavior modifications of microplastics by microalgae. Environ Int 107382.10.1016/j.envint.2022.107382 PubMed

Kim GY, Park HS, Nam BH, et al. Purification and characterization of acidic proteo-heteroglycan from the fruiting body of Phellinus linteus (Berk. & M.A. Curtis) Teng. Biores Technol. 2003;89:81–87. doi: 10.1016/S0960-8524(02)00273-0. PubMed DOI

Leiser R, Jongsma R, Bakenhus I, et al. Interaction of cyanobacteria with calcium facilitates the sedimentation of microplastics in a eutrophic reservoir. Water Res. 2021;189:116582. doi: 10.1016/j.watres.2020.116582. PubMed DOI

Leiser R, Wu GM, Neu TR, Wendt-Potthoff K. Biofouling, metal sorption and aggregation are related to sinking of microplastics in a stratified reservoir. Water Res. 2020;176:115748. doi: 10.1016/j.watres.2020.115748. PubMed DOI

Liu P, Qian L, Wang H, et al. New insights into the aging behavior of microplastics accelerated by advanced oxidation processes. Environ Sci Technol. 2019;53:3579–3588. doi: 10.1021/acs.est.9b00493. PubMed DOI

Liu P, Shi Y, Wu X, et al. Review of the artificially-accelerated aging technology and ecological risk of microplastics. Sci Total Environ. 2021;768:144969. doi: 10.1016/j.scitotenv.2021.144969. PubMed DOI

Liu X, Deng Q, Zheng Y, et al. Microplastics aging in wastewater treatment plants: focusing on physicochemical characteristics changes and corresponding environmental risks. Water Res. 2022;221:118780. doi: 10.1016/j.watres.2022.118780. PubMed DOI

Luo H, Liu C, He D, et al. Environmental behaviors of microplastics in aquatic systems: a systematic review on degradation, adsorption, toxicity and biofilm under aging conditions. J Hazard Mater. 2022;423:126915. doi: 10.1016/j.jhazmat.2021.126915. PubMed DOI

Luo H, Zeng Y, Zhao Y, et al. Effects of advanced oxidation processes on leachates and properties of microplastics. J Hazard Mater. 2021;413:125342. doi: 10.1016/j.jhazmat.2021.125342. PubMed DOI

Luo H, Zhao Y, Li Y, et al. Aging of microplastics affects their surface properties, thermal decomposition, additives leaching and interactions in simulated fluids. Sci Total Environ. 2020;714:136862. doi: 10.1016/j.scitotenv.2020.136862. PubMed DOI

Madadi R, Maljaee H, Serafim LS, Ventura SPM. Microalgae as contributors to produce biopolymers. Mar Drugs. 2021;19:466. doi: 10.3390/MD19080466. PubMed DOI PMC

Martínez KI, González-Mota R, Soto-Bernal JJ, Rosales-Candelas I. Evaluation by IR spectroscopy of the degradation of different types of commercial polyethylene exposed to UV radiation and domestic compost in ambient conditions. J Appl Polym Sci. 2021;138:50158. doi: 10.1002/app.50158. DOI

Meng J, Xu B, Liu F, et al. Effects of chemical and natural ageing on the release of potentially toxic metal additives in commercial PVC microplastics. Chemosphere. 2021;283:131274. doi: 10.1016/j.chemosphere.2021.131274. PubMed DOI

Miao L, Gao Y, Adyel TM, et al. Effects of biofilm colonization on the sinking of microplastics in three freshwater environments. J Hazard Mater. 2021;413:125370. doi: 10.1016/j.jhazmat.2021.125370. PubMed DOI

Miao L, Yu Y, Adyel TM, et al. Distinct microbial metabolic activities of biofilms colonizing microplastics in three freshwater ecosystems. J Hazard Mater. 2021;403:123577. doi: 10.1016/j.jhazmat.2020.123577. PubMed DOI

Min K, Cuiffi JD, Mathers RT. Ranking environmental degradation trends of plastic marine debris based on physical properties and molecular structure. Nat Commun. 2020;11:727. doi: 10.1038/s41467-020-14538-z. PubMed DOI PMC

Miranda MN, Sampaio MJ, Tavares PB, et al. Aging assessment of microplastics (LDPE, PET and uPVC) under urban environment stressors. Sci Total Environ. 2021;796:148914. doi: 10.1016/j.scitotenv.2021.148914. PubMed DOI

Monticelli D, Castelletti A, Civati D, et al. How to efficiently produce ultrapure acids. International Journal of Analytical Chemistry. 2019;2019:1–5. doi: 10.1155/2019/5180610. PubMed DOI PMC

Mosca Angelucci D, Tomei MC (2020) Uptake/release of organic contaminants by microplastics: a critical review of influencing factors, mechanistic modeling, and thermodynamic prediction methods. Crit Rev Environ Sci Technol 1–45.10.1080/10643389.2020.1856594

Nava V, Leoni B. A critical review of interactions between microplastics, microalgae and aquatic ecosystem function. Water Res. 2021;188:116476. doi: 10.1016/j.watres.2020.116476. PubMed DOI

Nava V, Matias MG, Castillo-Escrivà A, et al. Microalgae colonization of different microplastic polymers in experimental mesocosms across an environmental gradient. Glob Change Biol. 2021 doi: 10.1111/gcb.15989. PubMed DOI PMC

Nielson RC. Extraction and quantitation of polyolefin additives. J Liq Chromatogr. 1991;14:503–519. doi: 10.1080/01483919108049266. DOI

Nizzetto L, Bussi G, Futter MN, et al. A theoretical assessment of microplastic transport in river catchments and their retention by soils and river sediments. Environ Sci Process Impacts. 2016;18:1050–1059. doi: 10.1039/c6em00206d. PubMed DOI

OECD . Alga, growth inhibition test. Paris, France: OECD Publishing; 1984.

OriginLab Corporation . Origin, version 2018. MA, USA: Northampton; 2018.

Parker FS. Applications of Infrared Spectroscopy in Biochemistry, Biology, and Medicine. US, Boston, MA: Springer; 1971. Amides and amines; pp. 165–172.

Pickett JE (2018) Weathering of plastics. In: Handbook of Environmental Degradation Of Materials: Third Edition. Elsevier, pp 163–184

Pieristè M, Chauvat M, Kotilainen TK, et al. Solar UV – a radiation and blue light enhance tree leaf litter decomposition in a temperate forest. Oecologia. 2019;191:191–203. doi: 10.1007/s00442-019-04478-x. PubMed DOI PMC

R Core Team . R: a language and environment for statistical computing. Vienna, Austria: R Foundation for Statistical Computing; 2014.

Rahman MM, Al-Sulaimi S, Farooque AM. Characterization of new and fouled SWRO membranes by ATR/FTIR spectroscopy. Appl Water Sci. 2018;8:183. doi: 10.1007/s13201-018-0806-7. DOI

Rastogi RP, Madamwar D, Nakamoto H, Incharoensakdi A. Resilience and self-regulation processes of microalgae under UV radiation stress. J Photochem Photobiol, C. 2020;43:100322. doi: 10.1016/j.jphotochemrev.2019.100322. DOI

Rosenfeldt EJ, Linden KG. The ROH, UV concept to characterize and the model UV/H 2O2 process in natural waters. Environ Sci Technol. 2007;41:2548–2553. doi: 10.1021/es062353p. PubMed DOI

Ross GJ, Watts JF, Hill MP, Morrissey P. Surface modification of poly(vinylidene fluoride) by alkaline treatment: 1. The Degradation Mechanism Polymer. 2000;41:1685–1696. doi: 10.1016/S0032-3861(99)00343-2. DOI

Rummel CD, Jahnke A, Gorokhova E, et al. Impacts of biofilm formation on the fate and potential effects of microplastic in the aquatic environment. Environ Sci Technol Lett. 2017;4:258–267. doi: 10.1021/acs.estlett.7b00164. DOI

Rummel CD, Lechtenfeld OJ, Kallies R, et al. Conditioning film and early biofilm succession on plastic surfaces. Environ Sci Technol. 2021;55:11006–11018. doi: 10.1021/acs.est.0c07875. PubMed DOI

Sarkar AK, Rubin AE, Zucker I. Engineered polystyrene-based microplastics of high environmental relevance. Environ Sci Technol. 2021;55:10491–10501. doi: 10.1021/acs.est.1c02196. PubMed DOI PMC

Schell T, Hurley R, Nizzetto L et al (2021) Spatio-temporal distribution of microplastics in a Mediterranean river catchment: the importance of wastewater as an environmental pathway. J Hazard Mater 126481.10.1016/j.jhazmat.2021.126481 PubMed

Schwarz AE, Ligthart TN, Boukris E, van Harmelen T. Sources, transport, and accumulation of different types of plastic litter in aquatic environments: a review study. Mar Pollut Bull. 2019;143:92–100. doi: 10.1016/j.marpolbul.2019.04.029. PubMed DOI

Seeley ME, Song B, Passie R, Hale RC. Microplastics affect sedimentary microbial communities and nitrogen cycling. Nat Commun. 2020;11:2372. doi: 10.1038/s41467-020-16235-3. PubMed DOI PMC

Smith IL, Stanton T, Law A. Plastic habitats: algal biofilms on photic and aphotic plastics. Journal of Hazardous Materials Letters. 2021;2:100038. doi: 10.1016/j.hazl.2021.100038. DOI

Song YK, Hong SH, Jang M, et al. Combined effects of UV exposure duration and mechanical abrasion on microplastic fragmentation by polymer type. Environ Sci Technol. 2017;51:4368–4376. doi: 10.1021/acs.est.6b06155. PubMed DOI

Tu C, Chen T, Zhou Q, et al. Biofilm formation and its influences on the properties of microplastics as affected by exposure time and depth in the seawater. Sci Total Environ. 2020;734:139237. doi: 10.1016/j.scitotenv.2020.139237. PubMed DOI

Velez JFM, Shashoua Y, Syberg K, Khan FR. Considerations on the use of equilibrium models for the characterisation of HOC-microplastic interactions in vector studies. Chemosphere. 2018;210:359–365. doi: 10.1016/j.chemosphere.2018.07.020. PubMed DOI

Wang T, Ma Y, Ji R. Aging processes of polyethylene mulch films and preparation of microplastics with environmental characteristics. Bull Environ Contam Toxicol. 2021;107:736–740. doi: 10.1007/s00128-020-02975-x. PubMed DOI

Xiong Q, Hu LX, Liu YS, et al. New insight into the toxic effects of chloramphenicol and roxithromycin to algae using FTIR spectroscopy. Aquat Toxicol. 2019;207:197–207. doi: 10.1016/j.aquatox.2018.12.017. PubMed DOI

Xiong Q, Liu Y-S, Hu L-X, et al. Levofloxacin and sulfamethoxazole induced alterations of biomolecules in Pseudokirchneriella subcapitata. Chemosphere. 2020;253:126722. doi: 10.1016/j.chemosphere.2020.126722. PubMed DOI

Yang Y, Li Z, Yan C, et al. Kinetics of microplastic generation from different types of mulch films in agricultural soil. Sci Total Environ. 2021;814:152572. doi: 10.1016/j.scitotenv.2021.152572. PubMed DOI

Zha F, Shang M, Ouyang Z, Guo X. The aging behaviors and release of microplastics: a review. Gondwana Res. 2021 doi: 10.1016/j.gr.2021.10.025. DOI

Zvekic M, Richards LC, Tong CC, Krogh ET. Characterizing photochemical ageing processes of microplastic materials using multivariate analysis of infrared spectra. Environ Sci Process Impacts. 2022;24:52–61. doi: 10.1039/d1em00392e. PubMed DOI