No description available.

<p>  </p> <p>Plastics are the most common polymers used in various industries. However, million tons of plastics are produced and disposed every year around the world, and part of them end up entering the environment and agricultural ecosystems in the form of microplastics. Microplastics have become an environmental and health threat to aquatic species and humans because they are small and can easily reach water bodies for municipal and agricultural uses. Microplastics have been traced in food commodities and products derived from animals and even found in bottles of drinking water. As an approach to permanently remediating microplastics, current microplastic degradation techniques, however, require high energy inputs and thus are generally not cost-efficient. High-voltage atmospheric cold plasma (HVACP) is a low-cost energy-efficient technology to produce highly reactive species that can induce physicochemical changes in polymers. This study, for the first time, used HVACP as a novel remediation strategy for microplastics. HVACP was generated by dielectric barrier discharge at 50 kV using oxygen, nitrogen, or their mixture as working gas. Two types of microplastics, polypropylene (PP) and low-density polyethylene (LDPE), were treated for 30 min, and the effect of 24-h post-treatment was also studied. The properties of HVACP-treated microplastics, including weight, particle size, crystallinity, melting point, carbonyl index (CI), and surface morphology, were comprehensively analyzed. HVACP treatments were found effective in degrading both PP and LDPE microplastics. A larger extent of degradation was observed with PP microplastics treated by O/N mixture plasma, but the nitrogen plasma-treated sample showed a higher degree of oxidation according to its CI. For PE microplastics, oxygen plasma caused more degradation, but post-treatment did not promote further oxidation. The results indicated two potential mechanisms for microplastic degradation by HVACP. LDPE microplastics were degraded by oxidative reactions caused by highly reactive oxygen species, and PP microplastics followed a hydrolytic pathway of degradation as they became more hydrophilic after HVACP treatment. This study proved that HVACP is a promising method for microplastic degradation, and thus has great potential for addressing the severe challenges of microplastics that the food and agriculture sectors are currently facing.</p>

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.

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

Enligt EU:s klimatlag ska regionen till år 2050 vara klimatneutral, och som en del i det arbetet har Sveriges riksdag upprättat ett nationellt mål om att Sverige år 2040 ska ha enbart förnybar elproduktion. Därför har Energimyndigheten i samarbete med Naturvårdsverket tagit fram en strategi för en hållbar utbyggnad av vindkraften. Större vindkraftsetableringar för med sig ingrepp i miljön som kan påverka såväl djur och natur som människor. I media och andra forum, såsom på hemsidor för olika organisationer mot vindkraft, pågår en debatt kring vindkraftens för- och nackdelar, och syftet med den här studien var att undersöka huruvida de farhågor rörande miljö och hälsa som uttrycks inför landbaserade vindkraftsetableringar stämmer överens med forskning och upplevelsen hos människor som lever med vindkraft i sin närhet.  Argument mot vindkraft identifierades genom sökning i dagspress, och information om vindkraftens konsekvenser samlades in genom en enkätundersökning med personer som bodde i närheten av vindkraft och med hjälp av vetenskapliga artiklar och rapporter från statliga myndigheter. Argumenten avgränsades till negativa effekter på människors hälsa med avseende på ljus, buller (inklusive infraljud) och utsläpp av mikroplaster och kemikalier; påverkan på naturen inklusive djurlivet, samt förändring av människors närmiljö. Respondenterna i enkätundersökningen var generellt sett positiva till vindkraft, och det som störde var främst ljudet, vilket för alla utom en endast upplevdes i begränsad omfattning. De vetenskapliga artiklar som studerades visade ett liknande resultat. De hälsorelaterade effekter som visades ha ett samband med vindkraft handlade om irritation och sömnstörningar på grund av ljudet. Sambandet konstaterades dock som komplext då andra faktorer såsom attityd också kunde ha en påverkan, vid sidan av ljudet som sådant. Vindkraften tycktes inte stå för några betydande utsläpp av mikroplaster, bisfenol-A eller PFAS, i jämförelse med andra källor. Kunskapsläget kring påverkan på natur och djurliv visades vara bristfälligt ur ett vetenskapligt perspektiv. Enkätstudien visade inte på någon omfattande påverkan av närmiljön, utan förändringar i landskapet upplevdes som något man vande sig vid. / According to the European Climate Law the region should be climate neutral by 2050, and as a part of that effort the Swedish parliament has set up a national goal that by the year 2040 Sweden should have only renewable electricity production. Therefore, the Swedish Energy Agency together with the Swedish Environmental Protection Agency has developed a strategy for a sustainable expansion of wind power. Larger installations of wind turbines entail interventions in the environment which can affect animals and nature as well as human beings. In media and other forums, like web sites for different organizations against wind power, there is an ongoing debate about the pros and cons of wind power, and the purpose of this study was to investigate if the concerns about the environment and health that comes up ahead of land-based wind power installations corresponds with science and the experience of people who live nearby wind turbines.  Argument against wind power wad identified through searching in daily newspaper, and information about the consequences of wind power was gathered through a survey with people living near wind turbines, and reports from government agencies. The arguments were limited to negative as well as through scientific articles effects on human health regarding to light, noise (including infrasound) and release of microplastics and chemicals; impact on nature including wildlife, and changes in people’s immediate environment. The respondents in the survey were generally positive towards wind power, and the main disturbance was the noise, which for all but one was experienced only to a limited extent. The scientific articles studied showed a similar result. The health-related effects associated with wind power were related to irritation and sleep disturbances due to the noise. However, the relationship was considered complex as other factors such as attitude also could have an impact beside the actual noise. Wind power did not seem to contribute to any significant emissions of microplastics, bisphenol-A or PFAS, compared to other sources. The state of knowledge regarding the impact on nature and wildlife was shown to be inadequate from a scientific perspective. The survey did not indicate any significant impact on the immediate environment, but changes in the landscape were perceived as something one got used to.

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.