Chapter 1 gives a general introduction into plastic polymer and microplastics including concepts, sources and distribution in the environment, microplastic sampling and analytical methods, and sampling area descriptions. Chapter 2 represents all methods and followed equipment used in the thesis. A double-filtration procedure preferable to Raman microscopy technique was developed to collect marine microplastics in brackish water from Can Gio and seawater from the East Sea. Chapter 3 is a comprehensive guideline on IR and Raman spectra interpretation of PE, PP, PVC, PS, PMMA, and polymer textiles, which is especially useful if the automatic library is not available. This chapter represents how to identify polymer type, predict sources and chemical behaviours of microplastics with the smallest size of 15 μm based on microscopic and spectroscopic data. Also, this chapter evaluates the sample handling workflows for salt, water and sand samples. Chapter 4 demonstrates the change in microplastic pollution from 250 MPs/L in Saigon urban canals (the center of Ho Chi Minh City), through UNESCO Can Gio Mangrove Biosphere Reserve (10 – 20 MPs/L), to estuaries of Saigon-Đong Nai River, Soai Rap River, Long Tau River (Ganh Rai Gulf), and eventually to the East Sea (3 – 5 MPs/L). Chapter 5 highlights the correlation of microplastic properties and compositions in beach sand and seawater in the coastal environment, particularly at Can Gio 30 April Tourist Beach. This is a pilot study to identify the differences and similarities in morphologies and compositions of microplastics accumulated in beach sand and distributed in seawater, thereby, concluding sources and transport routes of microplastics in the coastal environment. The results show that microplastics accumulated at concentrations from 0 to 92.56 MPs/kg from the surface to 20-cm sand layers. The seawater at Can Gio Beach and Đong Tranh Cape contained 6.44 and 3.75 MPs/L of microplastics, respectively. White polyethylene fragments predominated, and all the microplastics comprised small secondary microplastics with a minimum size of 25 µm and a maximum size of 260 µm for fragments and a length of 640 µm for fibers. The proportions of PE, PP, PS and PMMA were similar. The differing percentages of other compositions in sand and seawater are attributed to the morphology and density of the microplastics. Chapter 6 deals with the detection and determination of microplastics in Vietnamese sea salts. As a result, there was a higher fluctuation in microplastic amount amongs non-branded salts compared with branded salts. An average of 133.62 MPs/kg salt, corresponding to 487.71 microplastics entering the human body per year via salt consumption. More importantly, this chapter provides a convincing evidence for microplastic contamination in marine salts from the seawater. There are similarities in percentage, shape, size and colour of microplastics, especially PE, PET and PP extracted from sea salt and seawater collected in 3 different regions in Southern Vietnam (Can Gio Reserve and Vung Tau).:Chapter 1. Introduction 1.1. Synthetic polymers and plastic products 1.1.1. Overview of polymers and plastics 1.1.2. Plastic applications and global productions 1.1.2.1. Conventional plastics 1.1.2.2. Bioplastics 1.1.3. The life cycle of plastics and plastic pollution 1.2. Microplastics – definitions, sources and fate 1.2.1. Definition and classification of microplastics 1.2.2. Sources and pathways of microplastics into the environments 1.2.3. Global distribution and behaviours of microplastics in the environment 1.2.3.1. Physical behaviours: temporal and spatial accumulations 1.2.3.2. Chemical behaviours: Degradation and Adsorption 1.2.3.3. Biobehaviours: Ingestion, Translocation and Biodegradation 1.3. Effects and bioavailability of plastics on ecosystems, creatures and humans 1.3.1. Aquatic ecosystem 1.3.2. Terrestrial ecosystem 1.3.3. Food safety and human healths 1.4. Microplastic sampling techniques and analytical methods 1.4.1. Microplastic sampling techniques 1.4.1.1. Water sampling 1.4.1.2. Sediment sampling 1.4.2. Sample preparations for microplastic analysis 1.4.2.1. Matrix removal – oxidation and tissue digestion 1.4.2.2. Microplastic separation – density flotation and filtration 1.4.3. Microplastic qualification and quantification methods 1.4.3.1. Visual identification methods 1.4.3.2. Spectroscopic identification methods 1.4.3.3. Destructive thermal techniques 1.4.3.4. Summarized workflow from samples to the results on microplastics 1.4.3.5. Data expression Chapter 2. Materials and Methods 2.1. Materials 2.2. Microscopy-spectroscopy for microplastic quantification and qualification 2.3. Quality assurances (QA) and quality controls (QC) 2.4. Collected and interviewed data on the study areas 2.5. Water samples 2.6. Sand samples 2.7. Marine salt samples Chapter 3. The comprehensive guideline on micro-spectroscopic interpretation and sample preparations for microplastic analysis 3.1. Abstract 3.2. Visual characterizations of microplastics 3.3. Interpretation of IR and Raman spectra for plastic identification 3.4. The specificity of spectroscopies for identifying polymer type and chemical behaviours of sampled microplastics 3.4.1. Poly-Ethylene (PE) 3.4.2. Poly-Propylene (PP) 3.4.3. Poly-Vinyl Chloride (PVC) 3.4.4. Poly-Styrene (PS) 3.4.5. Poly Methyl Metacrylate (PMMA) 3.4.6. Poly-Ethylene Terephthalate (PET) 3.4.7. Poly-Amides-6, Nylon-6 (PA-6) 3.4.8. Similarity in Raman bands of pure plastics and sampled microplastics 3.5. The evaluation of sample treatment procedures 3.5.1. Salt samples 3.5.2. Sand samples 3.5.3. Water samples Chapter 4. Assessing microplastic prevalence and spatial dispersion from Saigon urban river network to East Sea by µ-Raman spectroscopy 4.1. Abstract 4.2. Microplastic pollution in the freshwater at Saigon urban canals 4.3. Microplastic pollution in the seawater at Can Gio Biosphere Reserve 4.4. Spatial and vertical dispersion of microplastics in the East Sea of Vietnam 4.5. Conclusions Chapter 5. Comparison of Microplastic Pollution in Beach Sediment and Seawater at UNESCO Can Gio Mangrove Biosphere Reserve 5.1. Abstract 5.2. Microplastic pollution in the sand at Can Gio Beach 5.2.1. Spatial variation in the microplastic amounts along the tidal lines 5.2.2. The abundance and composition of microplastics accumulated in sand layers 5.3. Microplastic pollution in seawater at Can Gio Beach and Đong Tranh Cape 5.4. Comparison of microplastic pollution between seawater and beach sand 5.5. Conclusions and recommendations Chapter 6. Microplastic contamination in Vietnamese sea salts 6.1. Abstract 6.2. The microplastics abundance in commercial sea salts 6.3. Microplastic pollution in the seawater taken at salt pans in Vietnam 6.4. Microplastic contamination in the sea salt collected at salt pans in Vietnam 6.5. Comparison of characteristics of microplastics in the seawater and sea salt 6.6. The enhanced toxicity of microplastics-contaminated salt consumption 6.7. Conclusions and recommendations Final Conclusions and Future Recommendations List of references Appendix Statistical data Photos taken on the sampling trips

No description available.

Les plasmas de décharges électriques qui entrent en contact avec des liquides ont suscité beaucoup d'attention depuis une cinquantaine d’années. En effet, les décharges avec des liquides se caractérisent par une réactivité chimique importante. Afin d’optimiser cette réactivité, de nombreuses études ont été effectuées en fonction de différents paramètres, tels que la configuration géométrique d’électrode, la composition du gaz, l’alimentation électrique (polarité, amplitude et fréquence), etc. Les travaux de recherche sur le traitement de l'eau par plasma et les applications environnementales ont débuté il y a plusieurs années. Plus récemment, la pollution par le plastique dans l’environnement marin et terrestre a créé un nouveau domaine d’applications des plasmas, en particulier ceux qui sont couplés avec un milieu liquide. Dans ce mémoire de maîtrise, les décharges en milieu liquide sont appliquées à la dégradation de polystyrène (PS) solide dans l’eau. Le point de départ de cette étude a été la réalisation d’un montage pointe - pointe : l’électrode de masse est immergée dans de l’eau déionisée et l’électrode de haute tension se trouve au-dessus de la phase liquide. Le PS se situe à l’interface air/eau. Une étude paramétrique est effectuée afin d’établir les paramètres optimaux pour la dégradation, en particulier la fréquence de répétition des décharges pour des valeurs entre 2 et 10 kHz. Pour ce faire, l’étude des caractéristiques électriques ainsi qu’optiques de chaque décharge permet de suivre ses propriétés au cours du traitement et de les coupler à la perte de masse de PS. À partir de ces données, il est possible de mettre en évidence un changement de régime de décharge à haute fréquence (10 kHz) : transition d’un streamer à un spark. De ce fait, il a été possible d’établir le rôle potentiel de chaque régime (streamer à spark) dans la dégradation du PS. Cette étude a permis de proposer un mécanisme de dégradation du polystyrène. Ainsi, nous avons trouvé qu’à 10 kHz, la dégradation du PS était maximisée avec une réduction de la masse de 83%, tandis qu’elle est de 50% à 5 kHz après traitement par un nombre de décharges équivalent. La caractérisation par FTIR du PS a montré que sa composition chimique ne change pas pendant la dégradation. Cependant, l’analyse de l’eau par résonance magnétique nucléaire a permis d’identifier la présence d’une faible quantité d’éthylbenzène comme sous-produit de dégradation. Les résultats présentés dans ce mémoire représentent une contribution à la compréhension de la dégradation de plastique par décharges électriques en milieu liquide. / Electric discharge plasmas that come into contact with liquids have attracted a great deal of attention over the last fifty years. Indeed, discharges with liquids are characterized by significant chemical reactivity. In order to optimize this reactivity, numerous studies have been carried out in relation to various parameters, such as electrode geometry, gas composition, power supply (polarity, amplitude and frequency), and so on. Research into plasma water treatment and environmental applications began several years ago. More recently, plastic pollution in the marine and terrestrial environment has created a new field of applications for plasmas, particularly those coupled with a liquid. In this master's thesis, liquid discharges are applied to the degradation of solid polystyrene (PS) in water. The starting point for this study was the realization of a tip-to-tip set-up. The ground electrode is immersed in deionized water, and the high-voltage electrode is above the liquid phase. The PS is located at the air/water interface. A parametric study is carried out to establish the optimum parameters for degradation, in particular the discharge repetition frequency for values between 2 and 10 kHz. The study of the electrical and optical characteristics of each discharge makes it possible to monitor its properties during processing, and to couple them to the mass loss of the PS. From these data, it is possible to highlight a change in discharge regime at high frequency (10 kHz): transition from streamer to spark. As a result, it was possible to establish the potential role of each regime (streamer to spark) in PS degradation. This study enabled us to determine the degradation mechanisms of polystyrene. We found that PS degradation was maximized at 10 kHz, with a mass reduction of 83%, while it was 50% at 5 kHz after treatment with an equivalent number of discharges. FTIR characterization of the PS showed that its chemical composition did not change during degradation. However, nuclear magnetic resonance analysis of the water identified the presence of a small amount of ethylbenzene as a degradation by-product. The results presented in this thesis represent a contribution to the understanding of plastic degradation by electrical discharges in liquid systems.

Microplastics are an emerging environmental contaminant. One of the ways microplastics can get into the environment is by the breakdown of larger plastics. These plastics can come from industrial practices, discarded fabrics, agriculture, and general plastic waste. As these plastics are broken down microplastics leach into the environment. The widespread use of plastics has resulted in the spread of microplastic contaminants all over the world. Microplastics have been reported to be in drinking water, so this paper is looking at the presence of microplastics in local communities of different demographics and socioeconomic statuses. In other studies of different drinking water contamination, minority, and low-income communities had worse quality water. In this paper, methods for sampling, extraction, and analysis with Laser Direct Infrared Spectroscopy were used. Out of Cities A, B, and C, City A, with the largest population, higher percentage of minorities, and worse off socioeconomic status, had the highest particle count. More research is needed in this field to find how socioeconomic status can affect exposure to microplastic contamination.

Les déchets plastiques et les produits issus de leurs fragmentations (microplastiques ou « MP », <5mm) représentent une menace globale et persistante pour l'ensemble des écosystèmes marins, du fait de leur facilité d'ingestion par une grande diversité d'espèces marines. La mer Méditerranée, de part sa nature semi-fermée et son littoral anthropisé, est très impactée par cette pollution. Cette thèse a pour objectif de mieux comprendre l'origine et le devenir des MP en mer, et ce, par la mise en place d'une stratégie d’échantillonnage le long du continuum terre-mer, i.e. des sources continentales aux récepteurs marins finaux. Cette approche holistique a été appliquée à l'échelle locale du golfe du Lion (Nord-Ouest de la Méditerranée) à l’ensemble des compartiments côtiers. Les MP ont été retrouvés dans toutes les matrices étudiées (eau, sédiment, dépôtatmosphérique et tissus biologiques) dans des quantités très variables à la fois dans les compartiments et entre les compartiments. Aucune sélection qualitative (forme, taille, polymère et couleur) majeure ne semble s'opérer lors du transfert des MP d'un compartiment à l'autre, et la majorité des MP sont des fibres. Quantitativement, la concentration des MP varie à des échelles temporelles et spatiales très courtes (<1 heure et <1 kilomètre). Si aucune relation claire entre les concentrations en MP et les forçages environnementaux (e.g. précipitation, débit des fleuves, vents, etc.) n'a été observée, les événements de précipitation semblent influencer grandement les quantités de MP transférées entre les compartiments. En extrapolant nos résultats aux bassins-versants du golfe du Lion, 30 ± 20 tonnes de MP se déposeraient via l'atmosphère sur les zones urbainescôtières et 7 ± 10 tonnes de MP seraient transportées par les fleuves vers la Méditerranée, chaque année. L'extrapolation des quantités de MP dans les compartiments marins, semble indiquer que la surface de la mer et les plages ne sont que des compartiments transitoires (< 1 tonne), tandis que les sédiments et la colonne d'eau sont potentiellement plus impactés (jusqu'à 350 tonnes pour les sédiments). De nouvelles données sont nécessaires pour la colonne d'eau et les sédiments pourconfirmer cette hypothèse, mais les résultats laissent penser qu'ils pourraient avoir un rôle majeur dans le stockage des MP. / Anthropogenic litter, particularly plastic litter and their fragments (microplastics or “MPs”; < 5 mm) represent a highly pervasive and persistent global threat to marine ecosystems, as they can be ingested by a wide range of marine species. As a landlocked sea with a high population density, the Mediterranean Sea is highly exposed to marine litter pollution. This thesis aims tounderstand the origin and the future of marine MPs thanks to a holistic approach from terrestrial sources to marine sinks. This strategy was applied at the regional scale of the Gulf of Lion (Northwestern Mediterranean Sea) on all coastal compartments. MPs were observed in every studied matrices (water, sediment, atmospheric fallout) with a high variability within and betweenthe different compartments. No significant qualitative trend seems to occur during the transfer of MPs between compartments and fibers were the most abundant shape found in samples. MP concentrations changed at a short spatial and temporal scale (< 1 hour and < 1 kilometer), overlaying other variabilities (i.e. seasonal or between sites). If no obvious relationship betweenexternal forcing (e.g. precipitations, river flow rates, winds) and MP concentrations was observed, rainfall events seemed to have an important impact on the amount of MPs transferred into the sea. Extrapolating our results to the whole Gulf of Lion watersheds, 30 ± 20 tons of MPs would settle on urban areas and 7 ± 10 tons would be supplied by rivers into the Mediterranean Sea every year. The extrapolation of MP quantities within marine environments seems to indicate that the sea surface and beaches are only transitory compartments (<1 ton) whereas sea floor and water column couldbe more impacted (up to 350 tons for marine sediment). New data on water column and marine sediments are needed to confirm this hypothesis, but those results suggest that both latter compartments could be major sinks for marine MPs.

<p>Mikroplastika&nbsp; je&nbsp; sveprisutna&nbsp; u&nbsp; vodenom&nbsp; ekosistemu&nbsp; pri&nbsp; čemu&nbsp; se&nbsp; često<br />ističe značaj ispitivanja njihovog uticaja na pona&scaron;anje drugih jedinjenja u vodi.<br />Pod pojmom mikroplastika podrazumevaju se plastične čestice manje od 5 mm.<br />Imajući u vidu potrebu za unapređenjem znanja o &scaron;tetnom uticaju mikroplastike<br />u životnoj sredini u ovom radu sproveden je set eksperimenata u kom je ispitivan<br />mehanizam&nbsp; interakcija&nbsp; koje&nbsp; se&nbsp; uspostavljaju&nbsp; prilikom&nbsp; adsorpcije&nbsp; hlorovanih<br />fenola,&nbsp; derivata&nbsp; benzena&nbsp; i&nbsp; policikličnih&nbsp; aromatičnih&nbsp; ugljovodonika&nbsp; na mikroplastici&nbsp; u&nbsp; vodenom&nbsp; matriksu.&nbsp; Kako&nbsp; bi&nbsp; se&nbsp; &scaron;to&nbsp; detaljnije&nbsp; razumeo&nbsp; uticaj mikroplastike&nbsp; i&nbsp; osobina&nbsp; vodenog&nbsp; matriksa&nbsp; na&nbsp; pona&scaron;anje&nbsp; organskih&nbsp; polutanata, laboratorijska ispitivanja su sprovedena u sintetičkom i realnom vodenommatriksu.&nbsp; Takođe&nbsp; je&nbsp; sprovedena&nbsp; optimizacija&nbsp; izolovanja&nbsp; i&nbsp; karakterizacije mikroplastike iz kozmetičkih sredstava u cilju procene uticaja osobina primarne mikroplastike na uspostavljanje interakcija sa organskim polutantima. Na&nbsp; osnovu&nbsp; dobijenih&nbsp; rezultata&nbsp; istraživanja&nbsp; može&nbsp; se&nbsp; zaključiti&nbsp; da&nbsp; se optimalna metoda izolovanja mikroplastike iz kozmetičkih sredstava zasniva na dodatnom&nbsp; tretiranju&nbsp; osu&scaron;enog&nbsp; materijala&nbsp; 30%&nbsp; vodonik-peroksidom,&nbsp; nakon ekstrakcije&nbsp; sredstva&nbsp; u&nbsp; destilovanoj&nbsp; vodi,&nbsp; u&nbsp; cilju&nbsp; dobijanja&nbsp; čistijih&nbsp; uzoraka mikroplastike. Promena brzine me&scaron;anja ima znčajan uticaj na promenu stepena adsorpcije ispitivanih grupa organskih jedinjenja.&nbsp; Uticaj se ogleda u povećanju stepena adsorpcije sa porastom brzine me&scaron;anja, a maksimalni procenat adsorpcije postignut&nbsp; je&nbsp; pri&nbsp; brzini&nbsp; me&scaron;anja&nbsp; od&nbsp; 150&nbsp; o/min.&nbsp; Dodatno,&nbsp; disperzija&nbsp; pra&scaron;kastih materijala u vodi nema značajan uticaj na promenu stepena adsorpcije hlorovanih fenola,&nbsp; derivata&nbsp; benzena&nbsp; i&nbsp; policikličnih&nbsp; aromatičnih&nbsp; ugljovodonika&nbsp; na mikroplastici.Ravnotežno&nbsp; stanje&nbsp; između&nbsp; koncentracije&nbsp; hlorovanih&nbsp; fenola,&nbsp; derivata<br />benzena&nbsp; i&nbsp; policikličnih&nbsp; aromatičnih&nbsp; ugljovodonika&nbsp; u&nbsp; vodi&nbsp; i&nbsp; odabranih predstavnika&nbsp; mikroplastike&nbsp; (PEp,&nbsp; PE_PCPs_1,&nbsp; PE_PCPs_2,&nbsp; PEg,&nbsp; PET,&nbsp; PP&nbsp; i PLA) uspostavlja se nakon 24 i 48 h kontakta u zavisnosti od vrste jedinjenja. Na promenu&nbsp; adsorpcionog&nbsp; afiniteta&nbsp; hlorovanih&nbsp; fenola,&nbsp; derivata&nbsp; benzena&nbsp; i policikličnih aromatičnih ugljovodonika prema mikroplastici utiču kako fizičkohemijske&nbsp; osobine&nbsp; jedinjenja&nbsp; tako&nbsp; i&nbsp; karakteristike&nbsp; mikroplastike.&nbsp; Na&nbsp; osnovu kinetičkih&nbsp; eksperimenata, najveći adsorpcioni afinitet ka mikroplastici&nbsp; ispoljili su&nbsp; derivati&nbsp; benzena&nbsp; (qt=103-350&nbsp; &micro;g/g),&nbsp; dok&nbsp; je&nbsp; najmanji&nbsp; uočen&nbsp; kod&nbsp; hlorovanih fenola&nbsp; (qt=25-225&nbsp; &micro;g/g).&nbsp; Dobijeni&nbsp; rezultati&nbsp; adsorpcije&nbsp; derivata&nbsp; benzena&nbsp; na ispitivanim&nbsp; česticama&nbsp; mikroplastike&nbsp; takođe&nbsp; su&nbsp; ukazali&nbsp; na&nbsp; veći&nbsp; afinitet&nbsp; ovih jedinjenja&nbsp; ka&nbsp; mikroplastici,&nbsp; u&nbsp; poređenju&nbsp; sa&nbsp; jedinjenjima&nbsp; iz&nbsp; grupe&nbsp; policikličnih aromatičnih&nbsp; ugljovodonika&nbsp; i&nbsp; hlorovanih&nbsp; fenola&nbsp; sličnih&nbsp; logKow&nbsp; vrednosti. Dodatno,&nbsp; uticaj&nbsp; vodenog&nbsp; matriksa&nbsp; na&nbsp; adsorpciju&nbsp; hlorovanih&nbsp; fenola,&nbsp; derivata benzena&nbsp; i&nbsp; policikličnih&nbsp; aromatičnih&nbsp; ugljovodonika&nbsp; na&nbsp; mikroplastici&nbsp; zavisi&nbsp; od same grupe jedinjenja kao i od vrste mikroplastike pri čemu je najmanje izražen u&nbsp; slučaju&nbsp; ispitivanih&nbsp; policikličnih&nbsp; aromatičnih&nbsp; ugljovodonika,&nbsp; a&nbsp; najvi&scaron;e&nbsp; kod hlorovanih fenola.Visoke&nbsp; vrednosti&nbsp; koeficijenta&nbsp; determinacije&nbsp; kinetičkog&nbsp; modela&nbsp; pseudodrugog&nbsp; reda&nbsp; za&nbsp; adsorpciju&nbsp; hlorovanih&nbsp; fenola,&nbsp; derivata&nbsp; benzena&nbsp; i&nbsp; policikličnih aromatičnih ugljovodonika na čestice mikroplastike ukazjuju da je hemisorpcija mogući&nbsp; mehanizam.&nbsp; Pored&nbsp; visokih&nbsp; vrednosti&nbsp; koeficijenata&nbsp; determinacije&nbsp; u slučaju svih odabranih organskih jedninjenja dobijena konstanta brzine drugog reda&nbsp; bila&nbsp; je&nbsp; manja&nbsp; od&nbsp; po četne&nbsp; brzine&nbsp; adsorpcije&nbsp; &scaron;to&nbsp; ukazuje&nbsp; na&nbsp; znatno&nbsp; brže odvijanje&nbsp; adsorpcije&nbsp; pri&nbsp; kraćim&nbsp; vremenima&nbsp; kontakta&nbsp; (12-24&nbsp; h)&nbsp; nakon&nbsp; čega&nbsp; je<br />dolazilo do usporavanja procesa adsorpcije.Mehanizam adsorpcije hlorovanih fenola, derivata benzena i policikličnih aromatičnih ugljovodonika&nbsp; ispitivan&nbsp; je primenom Freundlich-ovog, Langmuirovog,&nbsp; Redlich-Peterson-ovog&nbsp; i&nbsp; Dubinine-Radusckevich-evog&nbsp; adsorpcionog modela. Vrednosti Freundlich-ovog eksponenta za adsorpciju hlorovanih fenola, derivata benzena i&nbsp; policikličnih aromatičnih ugljovodonika bile su manje od 1,<br />&scaron;to ukazuje na to da je slobodna energije adsorpcije na mikroplastci opadala sa povećanjem&nbsp; inicijalne&nbsp; koncetracije&nbsp; ispitivanih&nbsp; polutanata.&nbsp; Vrednosti maksimalnog adsorpcionog kapaciteta dobijene za&nbsp; adsorpcione procese PAH&nbsp; na česticama mikroplastike bile su u opsegu od 29,7-2596,5 &micro;g/g. Visoke vrednosti maksimalnih adsorpcionih kapaciteta dobijene su takođe za adsorpciju derivata benzena na ispitivanim vrstama mikroplastike&nbsp; 39,3-2010,1 &micro;g/g. S druge strane, uočeno&nbsp; je&nbsp; različito&nbsp; adsorpciono&nbsp; pon&scaron;anje&nbsp; hlorovanih&nbsp; fenola&nbsp; u&nbsp; zavisnosti&nbsp; od vodenog metriksa u kom su eksperimenti sprovedeni pri čemu su&nbsp; qmax&nbsp; vrednosti iznosile 20,00-205,6 &micro;g/g. Značajan uticaj&nbsp; pH vrednosti vodenog matriksa&nbsp; utvrđen je&nbsp; za adsorpciju hlorovanih&nbsp; fenola&nbsp; na&nbsp; mikroplastici,&nbsp; dok&nbsp; u&nbsp; slučaju&nbsp; derivata&nbsp; benzena&nbsp; i&nbsp; PAH promena pH vrednosti vodenog matriksa nije pokazala značajan uticaj. Rezultati dobijeni&nbsp; za&nbsp; adsorpciju&nbsp; hlorovanih&nbsp; fenola&nbsp; na&nbsp; mikroplastici&nbsp; ukazuju&nbsp; na&nbsp; nižu tendenciju&nbsp; ka&nbsp; formiranju&nbsp; interakcija&nbsp; hlorovanih&nbsp; fenola&nbsp; sa&nbsp; česticama mikroplastike pri pH 4 i pH 10, pri čemu se stepen adsorpcije kretao u opsegu od 8-35% i 15-35%, respektivno, u odnosu na pH 7 (55-65%). Najniži&nbsp; adsorpcioni&nbsp; afinitet&nbsp; uočava&nbsp; se&nbsp; pri&nbsp; adsorpciji&nbsp; ispitivanih&nbsp; grupa jedinjenja na PLA. Može se pretpostaviti da će se organski polutanti,&nbsp;&nbsp; ukoliko ova vrsta mikroplastike dospe u vodene sisteme, slabo vezivati na ovaj materijal pri čemu će značajno manje uticati na njihov trasport kroz životnu sredinu, u odnosu<br />na druge ispitivane vrste mikroplastike. Na&nbsp; osnovu&nbsp; dobijenih&nbsp; rezultata&nbsp; istraživanja&nbsp; može&nbsp; se&nbsp; zaključiti&nbsp; da&nbsp; na adsorpciju ispitivanih grupa organskih jedinjenja i mikroplastike značajan uticaj imaju&nbsp; fizičko-hemijske&nbsp; osobine&nbsp; ispitivanih&nbsp; jedinjenja&nbsp; kao&nbsp; &scaron;to&nbsp; su&nbsp; kiselinska konstanta, veličina molekula, hidrofobnost, stukturni raspored i dr. Pored toga, karakteristike vodenog matriksa, među kojima je najvažnija pH vrednost, imaju značajan&nbsp; uticaj&nbsp; na&nbsp; adsorpcioni&nbsp; afinitet&nbsp; jedinjenja&nbsp; ka&nbsp; mikroplastici.&nbsp; Dodatno,<br />struktura&nbsp; i&nbsp; poreklo&nbsp; polimera&nbsp; ima&nbsp; veliki&nbsp; uticaj&nbsp; na&nbsp; formiranje&nbsp; interakcija&nbsp; sa<br />ispitivanim grupama organskih polutanata. Dobijeni rezultati takođe ukazuju na<br />nemogućnost&nbsp; određivanje&nbsp; unifomnog&nbsp; mehanizma&nbsp; adsorpcije&nbsp; organskih<br />jedinjenja na česticama mikroplastike u vodi.</p> / <p>Microplastics&nbsp; are&nbsp; ubiquitous&nbsp; in&nbsp; aquatic&nbsp; ecosystems,&nbsp; so&nbsp; it&nbsp; is&nbsp; essential&nbsp; to study their&nbsp; impact on the behaviour of other compounds which are commonly present in water. The term microplastics refers to all plastic particles smaller than 5 mm. In order&nbsp; to address knowledge gaps relating to the potential harmful effects of microplastics in the environment, the experiments conducted during this thesis were designed to investigate the adsorption mechanism of chlorinated phenols, benzene derivatives, and polycyclic aromatic hydrocarbons on microplastics in water.&nbsp; To&nbsp; provide&nbsp; a&nbsp; more&nbsp; detailed&nbsp; understanding&nbsp; of&nbsp; the&nbsp; influence&nbsp; of&nbsp; different water&nbsp; matrices&nbsp; on&nbsp; adsorption&nbsp; properties&nbsp; of&nbsp; microplastics,&nbsp; experiments&nbsp; were conducted in both synthetic and real water matrices. In the course of this work, methods were optimised for the isolation and characterization of microplastifrom personal care products, in order to allow investigation&nbsp; of the influence of the&nbsp; properties&nbsp; of&nbsp; primary&nbsp; microplastics&nbsp; on&nbsp; their&nbsp; interactions&nbsp; with&nbsp; organic pollutants.Base on the obtained results, it can be concluded that the optimal method of isolating microplastics from personal care products is based&nbsp; on treating already dried&nbsp; material&nbsp; with&nbsp; 30%&nbsp; hydrogen&nbsp; peroxide,&nbsp; after&nbsp; extraction&nbsp; of&nbsp; the&nbsp; agent&nbsp; in distilled water, in order to obtain cleaner microplastic samples. The mixing rate was&nbsp; found&nbsp; to&nbsp; have&nbsp; a&nbsp; significant&nbsp; effect&nbsp; on&nbsp; the&nbsp; degree&nbsp; of&nbsp; adsorption&nbsp; of&nbsp; the investigated&nbsp; organic&nbsp; compounds.&nbsp; Increasing&nbsp; the&nbsp; mixing&nbsp; speed&nbsp; led&nbsp; to&nbsp; a&nbsp; higher<br />degree&nbsp; of&nbsp; adsorption,&nbsp; with&nbsp; the&nbsp; maximum&nbsp; adsorption&nbsp; percentage&nbsp; reached&nbsp; at&nbsp; a<br />mixing speed of 150 rpm. In addition, the dispersion of powdered materials in the&nbsp; water&nbsp; had&nbsp; no&nbsp; significant&nbsp; effect&nbsp; on the&nbsp; degree&nbsp; of&nbsp; adsorption&nbsp; of&nbsp; chlorinated phenols,&nbsp; benzene&nbsp; derivatives,&nbsp; and&nbsp; polycyclic&nbsp; aromatic&nbsp; hydrocarbons&nbsp; on microplastics.<br />The&nbsp; adsorption&nbsp; equilibrium&nbsp; between&nbsp; the&nbsp; concentration&nbsp; of&nbsp; chlorinated phenols,&nbsp; benzene derivatives and polycyclic aromatic hydrocarbons in water and selected types of microplastics (PEp, PE_PCPs_1, PE_PCPs_2, PEg, PET, PP, and&nbsp; PLA) was established after 24 and 48 h of contact time, depending on the selected&nbsp; group&nbsp; of&nbsp; organic&nbsp; pollutants.&nbsp; The&nbsp; adsorption&nbsp; affinity&nbsp; of&nbsp; chlorinated phenols,&nbsp; benzene&nbsp; derivatives,&nbsp; and&nbsp; polycyclic&nbsp; aromatic&nbsp; hydrocarbons&nbsp; towards microplastics&nbsp; was&nbsp; influenced&nbsp; by&nbsp; both&nbsp; the&nbsp; physicochemical&nbsp; properties&nbsp; of&nbsp; the compounds&nbsp; and&nbsp; the&nbsp; characteristics&nbsp; of&nbsp; the&nbsp; microplastics.&nbsp; Based&nbsp; on&nbsp; the&nbsp; kinetic experiments,&nbsp; the&nbsp; highest&nbsp; adsorption&nbsp; affinity&nbsp; for&nbsp; microplastics&nbsp; was&nbsp; shown&nbsp; by benzene derivatives (qt=103-350 &micro;g/g), while the lowest was&nbsp; observed during the adsorption of chlorinated phenols (qt=25-225 &micro;g/g). Benzene derivatives showed higher&nbsp; adsorption&nbsp; affinities&nbsp; for&nbsp; the&nbsp; selected&nbsp; microplastic&nbsp; particles&nbsp; than&nbsp; the polycyclic&nbsp; aromatic&nbsp; hydrocarbons&nbsp; and&nbsp; &nbsp; chlorinated&nbsp; phenols&nbsp; which&nbsp; had&nbsp; similar logKow&nbsp; values. The influence of the water matrix on adsorption of chlorinated phenols,&nbsp; benzene&nbsp; derivatives,&nbsp; and&nbsp; polycyclic&nbsp; aromatic&nbsp; hydrocarbons&nbsp; on microplastics&nbsp; depended&nbsp; on&nbsp; the&nbsp; specific&nbsp; functional&nbsp; groups&nbsp; of&nbsp; the&nbsp; investigated compounds as well as on the type of microplastics. Water matrix had little impact on&nbsp; the&nbsp; adsorption&nbsp; of&nbsp; polycyclic&nbsp; aromatic&nbsp; hydrocarbons&nbsp; on&nbsp; microplastics&nbsp; but greatly impacted the adsorption of chlorinated phenols. Fitting the pseudo-second order kinetic&nbsp; model to the&nbsp; adsorption data of chlorinated phenols, benzene derivatives, and polycyclic aromatic hydrocarbons on microplastic particles resulted in high correlation coefficients, indicating that chemisorption&nbsp; is&nbsp; the&nbsp; likely&nbsp; adsorption&nbsp; mechanism.&nbsp; In&nbsp; addition&nbsp; to&nbsp; the&nbsp; high correlation coefficients obtained for all the organic pollutants investigated, the pseudo-second order rate constants obtained were lower than the initiaadsorption rate, indicating significantly faster adsorption at shorter contact times (12-24 h), with adsorption slowing down as equilibrium was reached.The adsorption mechanism of chlorinated phenols, benzene derivatives,<br />and&nbsp; polycyclic&nbsp; aromatic&nbsp; hydrocarbons&nbsp; was&nbsp; investigated&nbsp; using Freundlich,Langmuir,&nbsp; Redlich-Peterson,&nbsp; Dubinine-Radusckevich,&nbsp; and&nbsp; Temkin&nbsp; adsorption models.&nbsp; The&nbsp; Freundlich&nbsp; exponent&nbsp; values&nbsp; for&nbsp; the&nbsp; adsorption&nbsp; of&nbsp; chlorinated phenols, benzene&nbsp; derivatives, and polycyclic&nbsp; aromatic&nbsp; hydrocarbons were&nbsp; less than 1 which indicates that the free energy of adsorption of these compounds on microplastics&nbsp; decreases&nbsp; as&nbsp; the&nbsp; initial&nbsp; concentration&nbsp; increases.&nbsp; The&nbsp; maximum adsorption capacities of PAHs on microplastic particles were in the range of 29.7-2596.5&nbsp; &micro;g/g.&nbsp; High&nbsp; maximum&nbsp; adsorption&nbsp; capacities&nbsp; were&nbsp; also obtained&nbsp; for the adsorption&nbsp; of&nbsp; benzene&nbsp; derivatives&nbsp; on&nbsp; the&nbsp; tested&nbsp; types&nbsp; of&nbsp; microplastics:&nbsp; 39.3-2010.1&nbsp; &micro;g/g.&nbsp; The&nbsp; chlorinated&nbsp; phenols&nbsp; behaved&nbsp; differently,&nbsp; and&nbsp; were&nbsp; more effected by the water matrix, with qmax values in&nbsp; the range 20.00-205.6 &micro;g/g. The pH of the water matrix was found to have a significant effect on the adsorption&nbsp; of&nbsp; chlorinated&nbsp; phenols&nbsp; on&nbsp; microplastics,&nbsp; whereas&nbsp; in&nbsp; the&nbsp; case&nbsp; of benzene&nbsp; derivatives&nbsp; and&nbsp; polycyclic&nbsp; aromatic&nbsp; hydrocarbons,&nbsp; the&nbsp; degree&nbsp; of<br />adsorption&nbsp; was&nbsp; largely&nbsp; independent&nbsp; of&nbsp; the&nbsp; water&nbsp; pH.&nbsp; For&nbsp; the&nbsp; adsorption&nbsp; of chlorinated&nbsp; phenols&nbsp; on&nbsp; microplastics,&nbsp; neutral&nbsp; pH&nbsp; conditions&nbsp; resulted&nbsp; in&nbsp; the greatest degrees of adsorption (55-65% at pH 7), while adsorption was inhibited under acidic (8-35% at pH 4) and basic (15-35% at pH 10) conditions. The microplastic type with the lowest observed adsorption affinities was PLA. It can be thus be assumed that in the event that this type of microplastic enters water systems, organic pollutants will only adsorb weakly to this material, such&nbsp; that&nbsp; it&nbsp; will&nbsp; have&nbsp; significantly&nbsp; less&nbsp; impact&nbsp; on&nbsp; the&nbsp; transport&nbsp; of&nbsp; the se compounds through the environment, than the other tested&nbsp; types of microplastics. The results obtained in this research demonstrate that the adsorption of the selected&nbsp; groups&nbsp; of&nbsp; organic&nbsp; pollutants&nbsp; on&nbsp; the&nbsp; microplastics&nbsp; investigated&nbsp; is significantly&nbsp; controlled&nbsp; by&nbsp; the&nbsp; physicochemical&nbsp; properties&nbsp; of&nbsp; the&nbsp; tested compounds, such as the dissociation constant, molecule&nbsp; size, hydrophobicity,<br />structural properties, etc. In addition, the characteristics of the water matrix play an important role in controlling adsorption of organic pollutants on microplastic, especially the water pH. In addition, the structure and aging of the polymers had a major influence&nbsp; on their interactions with the selected organic pollutants. The obtained&nbsp; results&nbsp; also&nbsp; demonstrate&nbsp; the&nbsp; difficulty&nbsp; in&nbsp; determining&nbsp; a&nbsp; uniform mechanism&nbsp; of&nbsp; adsorption&nbsp; between&nbsp; the&nbsp; various&nbsp; organic&nbsp; compounds&nbsp; and microplastic particles in water.</p>

Denna studie syftar till att undersöka hur miljötillsynsarbetet fungerar i de regioner som har direkt tillverkning av plastpellets, samt de som använder plastpellets som insatsvara vid produktion i Sverige. Studien undersöker också hur krav och miljötillsyn kan förhindra eventuella utsläpp av plastpellets och om uppfattningarna gällande dagens miljötillsynsarbete i Sverige skiljer sig åt mellan verksamheter och tillsynsmyndigheter. Resultaten samlades in genom två enkäter, en anpassad till verksamheter och en anpassad till tillsynsmyndigheter, samt genom två intervjuer. Enkäterna hade 18 respondenter från myndigheter och 20 respondenter från verksamheter. De två intervjuerna inkluderande plastbranschen och den tillsynsvägledande myndigheten. De kvantifierbara frågorna analyserades genom t-test och regressionsanalyser och de kvalitativa frågorna analyserades genom innehållsanalyser. Enligt studiens respondenter kan mer och likartad miljötillsyn, bra kommunikation och tydliga regelverk minska utsläpp av plastpellets. Det framkom även att en blandning av reglerande tillsyn och verksamheters frivilliga åtaganden är det som både myndigheter och verksamheter tror fungerar bäst för att förhindra utsläpp av plastpellets. Mer frekventa miljötillsynsbesök uppskattades av verksamheter, medan myndigheter inte hade sådana statistiska samband. Studien bekräftar att det finns olika uppfattningar kring miljötillsyn mellan verksamheter och tillsynsmyndigheter, men att frågan är komplex och kräver ytterligare forskning. / This study aims to investigate how environmental supervision works in the regions that have direct production of plastic pellets, and those that use plastic pellets as input in production in Sweden. The study examines how requirements and environmental supervision can prevent possible emissions of plastic pellets and whether perceptions regarding current environmental supervision in Sweden differ between industries and authorities. The results were collected through two questionnaires, one adapted to industries, one adapted to authorities, and two interviews. The questionnaires had 18 respondents from authorities and 20 respondents from industries. The two interviews included the plastics industry, and the guiding supervisory authority. The quantifiable questions were analysed by t-tests and regression analysis and the qualitative questions were analysed by content analysis. According to the study's respondents, more and similar environmental supervision, good communication and clear regulations can reduce emissions of plastic pellets. It also emerged that a mixture of regulatory supervision and the industries’ voluntary commitments is what both authorities, and industries believe works best to prevent emissions of plastic pellets. More frequent environmental inspection visits were appreciated by industries, while authorities did not have such statistical relations. The study confirms that there are different views on environmental supervision between industries and supervisory authorities, but that the issue is complex and requires further research.

Ackumuleringen av plast och mikroplast i miljön är idag en globalt aktuell fråga. Forskning kring mikroplast och dess påverkan på miljö och biota har ökat kraftigt det senaste decenniet. En av de största utsläppskällorna till mikroplast är slitage från vägtrafiken, speciellt från däck, men mikroplast kan även komma från vägmarkeringar. Vägmarkeringar innehåller plastpolymerer (som bindemedel), fyllnadsmedel, pigment och tillsatsämnen (additiv), och ofta ingår även glaspärlor. Vissa ämnen kan ge en negativ påverkan på människa och miljö. I dagsläget saknas det data för att kunna kartlägga i vilken omfattning vägmarkeringsslitage bidrar till spridning av mikroplaster samt för att bedöma om och hur det skulle kunna påverka miljön och vattenlevande organismer. I detta examensarbete har toxicitetstest av lakvatten från vägmarkeringsprodukter utförts med algen Raphidocelis subcapitata för att studera om de är toxiska samt om det finns någon skillnad mellan olika vägmarkeringsprodukter. Partiklar från fyra olika typer av vägmarkeringsprodukter (prefabricerad termoplast, varmapplicerad termoplast, vattenbaserad akrylatfärg och 2-komponentsakrylatfärg) genererades och lakades var för sig med skakning i avjoniserat vatten under 24 timmar. Lakvattnen utan partiklar användes sedan till algtillväxthämningstest. Algerna exponerades under 72 timmar för lakvatten i olika koncentrationer, där den högsta motsvarade 100 g vägmarkeringspartiklar per liter, och algtillväxt mättes. Effektmåtten var maximal tillväxthastighet och lag-fas och dessutom analyserades korrelationen mellan dem som ett mått för anpassningseffektivitet. De fyra lakvattnen påverkade lag-fas och/eller tillväxthastighet i olika omfattning och medförde antingen inhibering eller stimulering av algtillväxten. Lakvattnet från den vattenbaserade akrylatfärgen påvisade störst inhibering av tillväxt och var även det mest toxiska eftersom ingen tillväxtanpassning skedde. För övriga lakvatten påvisades olika grad av anpassningseffektivitet av alger vid exponering. Dock krävs mer ingående statistisk utvärdering för att åtskilja de två lakvatten som hade minst påverkan, dvs. från den prefabricerade och den varmapplicerade termoplasten.  Detta är enbart en första studie. Upprepade tester med fler vägmarkeringsprodukter och fler tester med andra organismer, såsom bakterier, kärlväxter, kräftdjur och fisk, krävs för att bättre kunna utreda om och hur olika vägmarkeringar kan påverka biota. För ytterligare studier skulle det vara intressant att utvärdera vilka ämnen i vägmarkeringar som kan påverka miljön och om dessa skulle kunna ersättas med andra, mindre giftiga ämnen. / The accumulation of plastic and microplastics in the environment is a current global issue. Research on microplastics and its impact on the environment and biota has increased rapidly in the last decade. One of the largest sources of microplastics is wear from road traffic, especially tires, but they can also originate from road markings. Road markings contain plastic polymers (as a binder), fillers, pigments, and additives, and often also glass beads. Some substances may have a negative impact on humans and the environment. At present, there are no data to map the extent to which wear from road markings contributes to the emissions of microplastics, or to assess the effect they might cause on the environment and aquatic organisms. In this thesis, toxicity tests on leachates from road marking products were conducted on the alga Raphidocelis subcapitata to study the effect on the algae and if it differs between the different products.  Particles from four types of road marking products (prefabricated thermoplastic, hot-applied thermoplastic, acrylic water-based paint, and 2-component acrylic paint) were generated and leached separately by shaking in deionized water for 24 hours.  The leachates without particles were used in the standard algal growth inhibition tests. The algae were exposed for 72 hours to the leachates in different concentrations, with the highest corresponding to 100 g road marking particles per liter, and algal growth was monitored. Endpoints used were maximum growth rate and lag phase and, in addition, their correlation was analyzed as an indicator for adaptation capacity. The four leachates affected lag phase and/or growth rate to a varying extent and caused inhibition or stimulation of algae growth. Exposure to leachate from the water-based acrylic paint showed most inhibition of growth and was also the most toxic as no growth adaptation was observed. For the other tests, different rates of adaptation efficiency of the algae growth were found. However, more detailed statistical evaluation is needed to differentiate between the two leachates that had the least effect, i.e. the prefabricated and the hot-applied thermoplastic. This is only a first study. More tests with more road marking products and with other organisms, such as bacteria, vascular plants, crustaceans, and fish, are required to better understand if and how different road markings could affect biota. Additionally, an evaluation of what substances in road marking materials may cause effects and whether these can be replaced by other, less toxic substances, would be of interest.

As plastic pollution increases, top marine predators such as marine mammals are becoming increasingly susceptible to plastic particles and their additives. Plastic particles have been found in gastrointestinal tracts and scat of many marine mammals, and quantifying plastic pollution in those that are pelagic can provide insight into plastic pollution in mesopelagic ecosystems that are just beginning to be analyzed. Adapting well-developed laboratory techniques for microplastic (MP) isolation (i.e. density separation and chemical digestion), I isolated MPs from the scat of the deepest diving pinniped, the northern elephant seal (NES), and found that100% of scat samples (n=11) contained high counts of MPs compared to other pinnipeds. Further, as plastic particles move through the digestive tract and potentially translocate into the circulation, body cells may be exposed to these plastic particles. Nanoplastics (NPs;<1μm) have been shown to affect cell viability and redox homeostasis in fish and human cells, while the lipophilic additives bisphenol-a (BPA) and bisphenol-s (BPS) used in plastics production are known endocrine disruptors. However, the effects of plastics (NPs) and plastics additives (BPA and BPS) have not been well-studied in marine mammals. To assess the direct impacts of NPs on marine mammal cells, I exposed fibroblasts isolated from NES skin (n=6 experiments) to polystyrene NPs of two different sizes (0.05μm and 0.5μm) and concentrations (3.64x109 and 3.64x1010 particles/mL) and did not find consistent effects on morphology and viability. Cell viability, which was quantified by an MTT assay, decreased as a result of NP exposure in two experimental replicates, but these results were not reproducible. I found that NPs did not have consistent effects on the morphology or viability of NES fibroblasts, regardless of their size or concentration. Lastly, I examined the effects of plastic additives on the physiology of marine mammal blubber tissue, the primary energy depot and reservoir of lipophilic pollutants. Precision-cut NES blubber slices were exposed to BPA and BPS, alone and in combination with the lipolytic hormone epinephrine, and I assessed their effects on the blubber transcriptome. I found that while BPA and BPS treatments alone did not have a pronounced effect on gene expression, they altered the expression of several genes associated with lipid homeostasis and adipogenesis. These data suggest that NES likely ingest MPs and maybe physiologically affected by exposure to plastic particles and their associated contaminants.

[ES] La alta escasez de agua y el constante incremento en la industrialización ha propiciado el deterioro de las reservas de agua como consecuencia de la excesiva generación y liberación de desechos contaminantes. Actualmente, se han reportado una gran variedad de contaminantes de diferente naturaleza, entre ellos se pueden mencionar los microplásticos (MPs) que han sido detectados en agua potable e incluso en animales para la ingesta humana lo cual puede acarrear graves problemas de salud. Cabe mencionar que uno de los mayores problemas a nivel medioambiental de los MPs radica en su alta estabilidad, ya que los métodos habituales utilizados para la eliminación de contaminantes no ejercen efecto. En este sentido, los Procesos de Oxidación Avanzada (POAs) han surgido como una alternativa a la eliminación de contaminantes de difícil degradación, debido a la generación principalmente de radicales hidroxilo que tienen un elevado potencial de oxidación y son muy poco selectivos. En este trabajo nos hemos centrado en el uso del proceso foto-Fenton, con sales de hierro y peróxido de hidrógeno e utilizando la luz solar como fuente de radiación, para llevar a cabo la degradación de MPs, específicamente la poliamida 6,6 (PA66), a pesar de que este polímero no es propiamente un plástico, la literatura lo considera dentro de ellos debido a su importancia como contaminante. A partir de PA66 obtenida de la industria textil, se evaluó el proceso de degradación con distintas técnicas y métodos analíticos destacando entre ellos la microscopía FESEM y la espectroscopía TF-IR. Se realizaron estudios en simulador solar en condiciones habituales de trabajo de procesos foto-Fenton (5 mg/L de Fe, 10 mg/L de H2O2 y pH = 2.8) y qué efectos podían producir tanto el tiempo de radiación como la presencia de una matriz natural como la salinidad en las aguas de tratamiento. Además, se realizaron estudios para confirmar que el proceso de degradación de la PA66 observado (numerosas imperfecciones aparecieron en la superficie del microplástico) era debido a la acción tanto del radical hidroxilo como del radical superóxido utilizando secuestrantes de ambos y comparando los procesos. Posteriormente se evaluó la degradación de la PA66 a nivel planta piloto utilizando dos diferentes fuentes de irradiación: LED vis y LED vis + solar realizando para ello, un estudio previo de diseño de experimentos tipo Doehlert para minimizar recursos y residuos y obtener las óptimas condiciones de tratamiento de la PA66 y, con base a estas condiciones se comparó la degradación de 4 diferentes MPs: PA66, poliamida 6 (PA6), aramida y poliéster (PES). Por último, se estudió la degradación de la PA66 bajo estas mismas condiciones en un periodo de 100 h. Los estudios de estabilidad mostraron que la PA66 no presenta fotólisis ni hidrólisis y los ensayos de degradación mediante el proceso foto-Fenton en un periodo de 7 h mostraron la formación de defectos sobre la superficie de la PA66 y disminución de grupos funcionales de acuerdo microscopia FESEM y FTIR, asimismo, el MP mostró cambios en su punto de fusión a diferentes tiempos de tratamiento como consecuencia de la rotura de las cadenas del polímero. Este mismo efecto se observó en un tiempo de degradación de 100 h de la PA66 con un aumento en el número y diámetro de defectos formados. La adición de NaCl a 30 g/L (alta salinidad) provocó una disminución en el daño generado debido a la reacción de los radicales hidroxilo y formación de especies reactivas con menor potencial de oxidación. La adición de 2-propanol y p-benzoquinona como atrapadores del radical hidroxilo y anión superóxido corroboraron esta suposición. La PA66 tratada en planta piloto mediante el uso de radiación LED vis + solar presentó un mayor grado de degradación en comparación con la tratada únicamente con radiación LED vis (incremento de 90 veces más el área superficial especifica de la PA66 tratada con respecto a la PA66 sin tratamiento). / [CA] L'alta escassetat d'aigua i el constant increment en la industrialització ha propiciat la deterioració dels cossos d'aigua a conseqüència de l'excessiva generació i alliberament de deixalles contaminants. Actualment, s'han reportat una gran varietat de contaminants de diferent naturalesa, entre ells es poden esmentar els microplàstics (MPs) que han sigut detectats en aigua potable i fins i tot en animals per a la ingesta humana la qual cosa pot implicar greus problemes de salut. Cal esmentar que un dels majors problemes a nivell mediambiental dels MPs radica en la seua alta estabilitat, ja que els mètodes habituals utilitzats per a l'eliminació de contaminants no exerceixen cap efecte. En aquest sentit, els Processos d'Oxidació Avançada (POAs) han sorgit com una alternativa a l'eliminació de contaminants de difícil degradació, a causa de la generació principalment de radicals hidroxil que tenen un elevat potencial d'oxidació i són molt poc selectius. En aquest treball ens hem centrat en l'ús del procés foto-Fenton, amb sals de ferro i peròxid d'hidrogen e utilitzant la llum solar com a font de radiació, per a dur a terme la degradació de MPs, específicament la poliamida 6,6 (PA66). A partir de PA66 obtinguda de la indústria tèxtil, es va avaluar el procés de degradació amb diferents tècniques i mètodes analítics destacant entre ells la microscòpia FESEM i la espectroscopía FT-IR. Es van realitzar estudis en simulador solar en condicions habituals de treball de processos foto-Fenton (5 mg/L de Fe, 10 mg/L de H2O2 i pH = 2.8) i quins efectes podien produir tant el temps de radiació com la presència d'una matriu natural com la salinitat en les aigües de tractament. A més, es van realitzar estudis per a confirmar que el procés de degradació de la PA66 observat (nombroses imperfeccions van aparèixer en la superfície del microplàstic) era degut a l'acció tant del radical hidroxil com del radical superòxid utilitzant segrestants de tots dos i comparant els processos. Posteriorment es va avaluar la degradació de la PA66 a nivell planta pilot utilitzant dues diferents fonts d'irradiació: LED vis i LED-vis + solar realitzant per a això, un estudi previ de disseny d'experiments tipus Doehlert per a minimitzar recursos i residus i obtindre les òptimes condicions de tractament de la PA66 i, amb base a aquestes condicions es va comparar la degradació de 4 diferents MPs (PA66, PA6, Aramida i PES). Finalment, es va estudiar la degradació de la PA66 sota aquestes mateixes condicions en un període de 100 h. Els estudis d'estabilitat van mostrar que la PA66 no presenta fotòlisis ni hidròlisi i els assajos de degradació mitjançant el procés foto-Fenton en un període de 7 h van mostrar la formació de defectes sobre la superfície de la PA66 i disminució de grups funcionals d'acord microscòpia FESEM i FT-IR, així mateix, el MP va mostrar canvis al punt de fusió a diferents temps de tractament a conseqüència del trencament de les cadenes del polímer. Aquest mateix efecte es va observar en un temps de degradació de 100 h de la PA66 amb un augment en el nombre de defectes formats i diàmetre dels defectes. L'addició de NaCl a 30 g/L (alta salinitat) va provocar una disminució en el mal generat a causa del secuestrament dels radicals hidroxil i formació d'espècies reactives amb menor potencial d'oxidació. L'addició de 2-propanol i p-benzoquinona com atrapadores del radical hidroxil i anió superòxid van corroborar aquesta suposició. La PA66 tractada en planta pilot mitjançant l'ús de radiació LED-vis + solar va presentar un major grau de degradació en comparació amb la tractada únicament amb radiació LED-vis (increment de 90 vegades més l'àrea superficial especifica de la PA66 tractada respecte a la PA66 sense tractament). L'avaluació de la degradació dels 4 MPs va mostrar que el PES i la aramida no són degradables en aquestes condicions i la PA6 va presentar una menor degradació que la PA66. / [EN] The high scarcity of water and the constant increase in industrialization has led to the deterioration of water bodies as a consequence of the excessive generation and release of pollutant wastes. Currently, a great variety of pollutants of different nature have been reported, among them we can mention microplastics (MPs) that have been detected in drinking water and even in animals for human consumption, which can cause serious health problems. It is worth mentioning that one of the biggest environmental problems of MPs lies in their high stability, since the usual methods used for the elimination of contaminants have no effect. In this sense, Advanced Oxidation Processes (AOPs) have emerged as an alternative for the removal of pollutants that are difficult to degrade, mainly due to the generation of hydroxyl radicals that have a high oxidation potential and are not very selective. In this work we have focused on the use of the photo-Fenton process, with iron salts and hydrogen peroxide and using sunlight as a source of radiation, to carry out the degradation of PMs, specifically polyamide 6,6 (PA66), despite that this polymer is not a plastic, literature considers it among them due to its importance as a pollutant. Using PA66 obtained from the textile industry, the degradation process was evaluated with different techniques and analytical methods, among them FESEM microscopy and TF-IR spectroscopy. Studies were carried out in a solar simulator under usual working conditions of photo-Fenton processes (5 mg/L Fe, 10 mg/L H2O2 and pH = 2.8) and it was studied the effect by the radiation time and the presence of a natural matrix such as salinity in the treatment water. In addition, studies were conducted to confirm that the PA66 degradation process observed (numerous imperfections appeared on the surface of the microplastic) was due to the action of both oxygen species (hydroxyl radical and the superoxide radical) by using scavengers of both and comparing the processes. Subsequently, PA66 degradation was evaluated at pilot plant level using two different irradiation sources: LED vis and LED vis + solar, a previous study of Doehlert type design of experiments to minimize resources and waste and obtain the optimal conditions for PA66 treatment and, based on these conditions the degradation of 4 different MPs: PA66, polyamide 6 (PA6), aramid and polyethylene (PES) was compared. Finally, the degradation of PA66 under these same conditions was studied over a period of 100 h. The stability studies showed that PA66 does not present photolysis or hydrolysis and the degradation tests by the photo-Fenton process in a period of 7 h showed the formation of defects on the surface of PA66 and decrease of functional groups according to FESEM and FTIR microscopy, also, the MP showed changes in its melting point at different treatment time as a result of the breaking of the polymer chains. This same effect was observed at a degradation time of 100 h of PA66 with an increase in the number of defects formed and in their diameters. The addition of NaCl at 30 g/L (high salinity) caused a decrease in the damage generated due to the reaction of hydroxyl radicals and formation of reactive species with lower oxidation potential. The addition of 2-propanol and p-benzoquinone as hydroxyl radical and superoxide anion scavengers corroborated this assumption. PA66 treated in pilot plant using LED vis + solar irradiation showed a higher degree of degradation compared to PA66 treated only with LED vis irradiation (90-fold increase in the specific surface area of treated PA66 with respect to untreated PA66). The evaluation of the degradation of the 4 MPs showed that PES and aramid are not degradable under these conditions and PA6 presented a lower degradation than PA66. / Marcelino Pérez, E. (2022). Proceso foto-Fenton como una alternativa en la degradación de microplásticos de poliamida presentes en aguas residuales textiles [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/191335