Dissertations / Theses on the topic 'Microplastic pollution'

Water pollution has long been considered a challenge in urban areas, and new types of pollution are continuously introduced to society. Urban wastewater and stormwater act as transport pathways of pollution from urban areas to receiving waterways. Microplastics are a new type of pollution that is being highlighted as problematic, and the presence of microplastics is widespread in the environment. The knowledge about behaviour, sources and transport pathways is still limited. Still, there have been suggestions for ways to control microplastic pollution. Moreover, many other pollutants have been introduced, and to a various extent controlled, in the urban water system before, which means that there are strategies for pollution control in place. The problem of microplastic pollution is receiving attention from both research and policy. Therefore, there is a need to simultaneously explore ways to handle the pollution and learn more about the flows of microplastics. The aim of this thesis is to contribute to the understanding of flows of microplastics in urban waters and investigate strategies and measures that can control the flows. This aim has been addressed through three different studies presented in the three appended papers. The empirical material was gathered between 2017 and 2020 using both quantitative and qualitative methods. The flows of microplastics were investigated using a quantitative approach with inspiration from substance flow analysis. Strategies and measures to control pollution were investigated by means of analyses of documents, literature review and interviews. In terms of flows, the results show that laundry seems to be a large contributor to the wastewater system, while the contribution from cigarette filters was smaller than anticipated. Littering, in general, as well as paint, are potentially important sources of microplastics where the understanding is very limited. In terms of strategies and measures to control the flows, there are both preventive and treatment options for microplastics. As microplastics are a diverse pollutant group, several different solutions are needed. Some aspects that influence control efforts are related to the properties and behaviour of the specific pollutant and can therefore be more or less suitable for different pollutants. Other aspects are more general, such as what compartments are seen as valuable and prioritised in terms of protection. Further, treatment moves the pollution from the water to another medium, and this movement also needs to be considered. Challenges in terms of changing, limited or even lack of legislation, as well as unclear responsibility, and problems with collaboration among urban actors also impact the possibilities to control pollution. The case of microplastics also raises questions about when and how pollution should be controlled and by whom. Further, emerging practices in the urban water system, such as source separation, pipe-separation, and water reuse, will have implications for how pollution will be handled in the future.

Microplastic are plastics that are < 5mm and is a contaminant of emerging concern in the aquatic environment. They are produced to be of a microscopic size or are created through the fragmentation of larger plastic material due to degradation. Microplastic has been found to be ubiquitous in the marine and freshwater environment with shoreline and deep sea sediment, oceans, rivers and lakes throughout the world observed to be polluted by microplastic. Wild populations of aquatic biota with various feeding behaviour have been observed to ingest microplastic. Exposure studies have also demonstrated the harmful effects of microplastic on a range of aquatic organisms. In this thesis, various aspects of microplastic pollution were investigated, from the sources of microplastic in the environment, to the destination of the microplastic once it enters the environment as well as the potential effects of microplastic on exposed organisms. The contribution a wastewater treatment works (WwTW) is making to microplastic pollution in the environment was estimated and the extraction efficiency of microplastic within the treatment process was determined. This study identified the key parts of microplastic removal in the treatment process. Aquaculture was also investigated as a source of microplastic in the environment by comparing synthetic rope and netting used in the industry with microplastic extracted from cultured fish and wild shellfish. The ingestion of microplastic by a variety of fish species sampled from Scottish marine waters were investigated finding considerably higher ingestion rates in demersal flatfish sampled from coastal waters then species sampled further offshore in much deeper waters. The effects of microplastic were investigate by developing a novel bioassay to measure ecologically relevant endpoints such as feeding and reproduction as well as morphology in Hydra attenuata exposed to microplastic. Hydra attenuata feeding was found to decrease as microplastic concentration increased. This work shows that microplastic is ubiquitous throughout the aquatic environment and can potentially effect exposed organisms.

Microplastics have increased water pollution, particularly in urban areas like Chicago. The purpose of this study was to explore how conflicts of interests and belief systems among different stakeholders can impede efforts for developing or revising plastic pollution mitigating laws. The theoretical foundation was Sabatier's advocacy coalition framework, which addresses public policies from the perspective of individual or organizational convictions. The research question addressed how policy makers can build coalitions among diverse stakeholders to formulate policies aimed at reducing microplastic pollution. A qualitative case study design included a document review and 12 semistructured interviews of participants drawn from 3 major different stakeholder groups. The interview data were transcribed, inductively coded and subjected to thematic analysis. The study showed universal stakeholder interest for the need for increased research on how microplastic pollution affects aquatic and human life. The results pointed to a moderate intensity of conflict among different stakeholders which enhances the likelihood for formulating microplastic pollution control policy. The study findings also show that policy-oriented learning can enhance increased stakeholder cooperation and lead to policy change on efforts to control microplastic pollution in waterways. Implications of the study for positive social change include increasing awareness of the sources and effects of plastic pollution, which may facilitate stakeholder cooperation and engineer the societal pressure required for formulating environmental and ecosystem protection policies. The result may be an improved environment and a reduction on the dangers of the plastic pollutants to aquatic and human lives.

A discrepancy between high plastic production rates and low recycling rates contributes to a ubiquitous plastic pollution problem. If this discrepancy persists, it is estimated that approximately 12 billion tons of plastics will accumulate in the environment by 2050. Although many countries have issued policies to limit the utilisation of single use plastics, the COVID-19 pandemic has increased demands for plastics and overwhelmed waste management systems. Thus, plastic pollution will persist, especially in marine environments where most mismanaged plastics accumulate. Plastics in the marine environment slowly disintegrate into microplastics (<5 mm) and adversely affect many animals when ingested. Thus, microplastics have recently been identified as an emerging contaminant of concern internationally, resulting in an exponential growth in the number of microplastic studies within the last decade. Studies in some ecologically important animals such as jellyfish, however, are preliminary. For example, jellyfish are claimed to ingest microplastics via trophic transfer and have been promoted as bioindicators for plastic pollution despite limited evidence. Moreover, although microplastics in the field are covered by biofilms, all jellyfish and microplastic experiments have used virgin microbeads that might underestimate ingestion rates. This thesis, therefore, tested three hypotheses: 1) that jellyfish would ingest microplastics and they would be adversely affected by microplastic ingestion (chapter 2), 2) that jellyfish would mainly accumulate microplastics via indirect ingestion (i.e. trophic transfer) and biofilms would promote ingestion rates (chapter 3), 3) that jellyfish would be useful bioindicators of microplastic pollution and treated wastewater would be a significant source of microplastics in an estuary (chapter 4). Medusae of Aurelia coerulea were exposed to 2,000 polystyrene microbeads L-1 and determined numbers of microbeads ingested. In addition, impacts of microbead ingestion on respiration rates and histology of their gut tissues were assessed (Chapter 2). No tissue damage was observed and respiration rates were unaffected by ingestion of microbeads. Importantly, the medusae ingested less than 0.2% of microbeads offered, egested microbeads within eight hours and stopped ingesting the microbeads after 16 hours, suggesting that the medusae may recognise virgin microbeads as non-food items. I, therefore, exposed the medusae to microbeads with photosynthetic biofilms, microbeads with heterotrophic biofilms and virgin microbeads (Chapter 3). Medusae ingested more microbeads with photosynthetic biofilms than microbeads with heterotrophic biofilms or virgin microbeads. The results highlight that the use of aged microbeads in experiments is important as the ingestion rates may be underestimated if virgin microbeads are used. Although jellyfish are claimed to acquire microbeads via trophic transfer, no studies had tested whether trophic transfer is a dominant pathway as jellyfish can also ingest microplastics directly from their surrounding water. Thus, I exposed ephyrae of Aurelia coerulea to aged microbeads (to test direct ingestion) and to Artemia nauplii fed aged microbeads (to test trophic transfer), and quantifued numbers of microbeads in the gastrovascular cavities (Chapter 3). I found that the ephyrae ingested 35 times more microbeads via trophic transfer than direct ingestion, suggesting that trophic transfer is the primary pathway by which jellyfish acquire microbeads. Furthermore, I investigated whether jellyfish in the field are susceptible to microplastic ingestion and whether jellyfish can be bioindicators of microplastic pollution. Water samples and medusae of Chrysaora cf pentostoma were collected nearby and distant from treated wastewater diffusers in two estuaries (the Gold Coast Broadwater and the Tweed River Estuary) that receive contrasting amounts of wastewater, to test whether microplastics in the guts of medusae represented those in the environment (Chapter 4). Only 83% of the medusae sampled contained microplastics and types and colours of microplastics in the gastrovascular cavities of jellyfish differed to those in the surrounding water. Thus, medusae are not good bioindicators of microplastic pollution because not all medusae acquire microplastics and the microplastics they accumulated did not reflect those in their environment. I also tested whether the released treated wastewater would have significant effects on microplastic concentrations and compositions in the receiving waters of the estuaries as wastewater treatment plants are claimed to be one of the significant sources of microplastics. I found no significant difference between microplastic concentrations and compositions nearby and distant from wastewater releases in either estuary. Thus, treated wastewater had no detectable impacts on microplastic concentrations and compositions in the receiving waters. Results from both laboratory and field experiments (Chapter2; Chapter 3; Chapter 4) strongly indicated that jellyfish accumulate relativly small amounts of microplastics and are poor bioindicators for microplastic pollution.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Sc
Science, Environment, Engineering and Technology
Full Text

The increasing amount of microplastics found in the environment have underscored the urgency to identify, develop and deploy scenarios in which municipal wastewater treatment plants (MWWTPs) limit the release of urban microplastics into the environment. Simultaneously, the global trend towards a circular economy has defined the conditions for these scenarios in relation to the water-energy- nutrient nexus. This study has created a novel framework between studies into treatment technologies for microplastics removal in wastewater streams and circular economic objectives from policymakers with regard to the water-energy-nutrient nexus. The results of this study build on the existing evidence that MWWTPs release significant amounts of microplastics to both terrestrial and aquatic environments. This study has demonstrated how Multi-criteria Analysis (MCA) can be applied to analyse wastewater treatment scenarios for their ability to limit microplastic pollution from MWWTPs, whilst taking the water-energy- nutrient nexus into account. The MCA has identified MBR inci-eco as the best performing circular economic scenario for limiting microplastic pollution from MWWTPs in to be constructed plants. This scenario includes a Membrane Bioreactor (MBR) with Anaerobic Digestion, energy recovery through incineration and Phosphorus recovery through Ecophos. If already existing MWWTPs aim to upgrade their facility to limit microplastic pollution, CASPACUF with Pyreg as an energy-nutrient recovery is seen as the best performing scenario. The powder activated carbon with ultra filtration (PAC-UF) system would then be installed as an additional polishing step to an existing conventional activated sludge (CAS) system, significantly reducing upfront investment costs. Academia can build upon these results to initiate additional research into novel microplastic filtration specific technologies, business model innovation for wastewater treatment and microplastic pollution prevention at the source and in stormwaters. National and international policymakers should ban the distribution and sale of biosolids for direct land application to limit the pollution of microplastics from bio-solids. Furthermore, efforts should be put in place to limit microplastic pollution at the source by stimulating policies for a ban on the use of microbeads, limit tyre wear and improving design for e.q. washing machines.
Den ökande mängden mikroplast som finns i miljön har understrukit brådskan i att identifiera, utveckla och tillämpa strategier där kommunala avloppsreningsverk (MWWTP) begränsar utsläpp av urbana mikroplaster. Samtidigt har den globala trenden mot en cirkulär ekonomi definierat villkoren för dessa scenarier i förhållande till vatten-energi-näring-näxan. Denna studie har tagit fram ett nytt ramverk mellan studier om reningsteknologier för avlägsnande av mikroplast i avloppsvattenströmmar och cirkulära ekonomiska mål från beslutsfattare med avseende på water-energy-nutrient nexus. Resultaten av denna studie bygger på befintliga bevis på att kommunala avloppsreningsverk släpper ut betydande mängder mikroplast i både mark- och vattenmiljöer. Denna studie har visat hur Multi-Criteria Analysis (MCA) kan användas för att analysera avloppsreningsscenarier utifrån deras förmåga att begränsa mikroplastföroreningar från reningsverk, samtidigt som man tar hänsyn till vatten-energi-näring-näxan. MCA har identifierat MBR-inci-eco som det bäst presterande cirkulära ekonomiska scenariot för att begränsa mikroplastföroreningar från nya verk. Detta scenario inkluderar en Membrane Bioreactor (MBR) med anaerobisk nebrytning, energiåtervinning genom förbränning och fosforåtervinning genom Ecophos. Om redan befintliga verk ska uppgradera sin anläggning för att begränsa mikroplastföroreningar, ses CASPACUF med Pyreg som energi-näringsåtervinning som det bästa scenariot. Det pulveraktiverade kolet med ultrafiltreringssystemet (PAC-UF) skulle sedan installeras som ett ytterligare poleringssteg till ett befintligt konventionellt system för aktiverat slam (CAS), vilket avsevärt minskar investeringskostnaderna. Framtida forskning kan använda dessa resultat för att undersöka nya mikroplastfiltreringsspecifika tekniker, affärsmodellinnovation för avloppsrening och förebyggande av mikroplastförorening vid källan och i stormvatten. Nationella och internationella beslutsfattare bör förbjuda distribution och försäljning av biosolids för direkt markanvändning för att begränsa mikroplastföroreningar från biosolids. Vidare bör åtgärder vidtas för att begränsa mikroplastföroreningar vid källan genom att stimulera policyer för ett förbud mot användning av mikrokulor, begränsa däckslitage och förbättra designen för e.q. tvättmaskiner.

Publisher version
The extent of microplastic pollution (< 5 mm) in the southern hemisphere, particularly southern Africa, is largely unknown. This study aimed to evaluate microplastic pollution along the south-eastern coastline of South Africa, looking at whether bays are characterised by higher microplastic densities than open stretches of coastline in both beach sediment and surf-zone water. Microplastic (mean ± standard error) densities in the beach sediment ranged between 688.9 ± 348.2 and 3308 ± 1449 particles·m− 2, while those in the water column varied between 257.9 ± 53.36 and 1215 ± 276.7 particles·m− 3. With few exceptions there were no significant spatial patterns in either the sediment or water column microplastic densities; with little differences in density between bays and the open coast (P > 0.05). These data indicate that the presence of microplastics were not associated with proximity to land-based sources or population density, but rather is governed by water circulation.

Microplastic pollution has been identified as an ever increasing proportion of marine litter. Despite an increase in microplastic awareness over the last decade, it represents an as yet unquantified threat to the marine environment. The relatively few studies that monitor its distribution and impact have illustrated a range of worrying effects on marine habitats and communities. The Clyde Sea Area (CSA) is subject to many sources of terrestrial and maritime plastic input. The use of plastics in recreational and commercial vessels throughout the CSA is believed to result in large levels of microplastic fibres, which have previously been seen to be ingested by a range of marine organisms. In a study of the breakdown of commonly used polymers in benthic environments, it was found that ropes of 10 mm diameter in sub-tidal conditions release between 0.086 and 0.422g of microfibers per meter per month in the early stages of degradation. This rate would be expected to increase over subsequent months, releasing substantial amounts of fibres into the CSA environment. In addition to the presence of numerous sources of microplastics, the CSA is relatively enclosed, and may accumulate high levels of debris as a result. Monthly sampling of the water and sediment in the CSA revealed contamination similar to that observed in other near-shore environments. Thus, it is expected that the potential threat to organisms in other areas will be similar to that observed in the CSA. One organism known to take up microplastics is the Norway lobster, Nephrops norvegicus, the target of the main fishery in the CSA. In this work we examined the levels of microplastic in the gut of N. norvegicus from the Scottish waters. Examination of individuals from the CSA revealed both a high occurrence and high accumulation of microplastic. This was found to be much greater than in N. norvegicus sampled from more remote Scottish waters. As a result, N. norvegicus from the CSA are most likely to suffer from the negative impacts associated with microplastic ingestion than those in offshore or in areas of low anthropogenic activity. In order to determine the potential impacts of microplastic ingestion on N. norvegicus, we first examined the mechanism by which N. norvegicus retain and egest microplastic. The position of microplastic aggregations in the foregut indicates that the gastric mill is the main obstacle to microplastic egestion. Inducing moult in microplastic-fed individuals demonstrated that expulsion of the gut lining during ecdysis enables N. norvegicus to reduce their plastic load, limiting plastic aggregation to the length of a single moult-cycle. In an 8 month controlled-feeding experiment retained plastic was seen to have a range of impacts on N. norvegicus. Feeding rate and body mass was seen to decrease in plastic loaded N. norvegicus, and a reduction was observed in a number of indicators of nutritional state. The results presented in this thesis have a number of implications to the CSA and wider marine environment. The similarity in the level of microplastic observed in the CSA to that of other studies of inshore waters indicates the potential for high microplastic uptake by crustaceans in those areas. The high variability in observed microplastic abundance suggests that small-scale monitoring is unsuitable for monitoring marine microplastic debris, and that use of an indicator species may provide a more reliable method of monitoring that is not subject to small-scale heterogeneity in distribution. The seasonal retention of microplastic by N. norvegicus indicates that crustaceans may provide a suitable indicator of local contamination. However, in the CSA, the high level of fibre aggregation and observed impacts of prolonged retention indicate that microplastic may be causing further pressure on an already exploited resource, reducing the stability of the valuable N. norvegicus population.

Microplastic is a widespread pollutant in marine and fresh water systems. A major pathway by which microplastics end up in these systems is via storm water. Storm water is generated as precipitation drain off of impenetrable surfaces like paving. Microplastic analysis of storm water make up a good foundation for better understanding what sources and factors contribute to microplastic pollution in marine and fresh water systems. This study puts emphasis on characterization and quantification of microplastics through visual characterization. As visual characterization is a subjective form of analysis, the characterization was performed based on guidelines in order to minimize the risk of identifying false positives. The concentration of microplastic was found to be higher in the current study than in comparison to larger water bodies and storm water streams in less urban areas. Fragments, i.e. irregular shaped particles with the appearance of being broken from a larger piece of litter, were found to be the most abundant type of microplastics, pointing at littering as a major source of microplastics in storm water.

Plastic pollution is a huge problem that is affecting all the oceans of the Earth. Plastic items end into the sea, break into tiny pieces and pollute the marine environment. The aim of this research is to increase our knowledge on this problem by comparing microplastic and zooplankton distributions. Samples from the Mediterranean Sea and Gibraltar Strait have been collected and analyzed. Plastic fragments have been extracted, weighted, photographed, measured and analyzed with a hyperspectral camera. The planktonic part of the samples has been analyzed identifying the main typology of organisms, taking pictures of the samples and analyzing them with ImageJ to take the measures. Data analysis was focused to the plastic to zooplankton ratio. The results have highlighted that most of the plastic to plankton ratios occurred in the in 1mm-10mm size range, and half of the stations in the Mediterranean sea presented values higher than 1, meaning than there is more plastic than plankton in that size range, for 50% of the Mediterranean. The ratio was higher during the day, due to the ascent of zooplankton during night. The results clearly show that the rank of greater danger is between 1mm to 10mm, and for this reason future samplings should focus on a net for this specific size range, to make sampling more simple and effective. A pollution indicator was created, based on the data collected all around the Mediterranean Sea, which could help find out future danger classifications, and choose the best adoptable strategies to solve the problem. Furthermore, the fact that the higher ratio has been found during the day can help future plastic sampling to focus on this time lapse. Concluding, the data provided by this research will be useful to better understand the degree of plastic contamination of our oceans and give updates to develop quality guidelines according to the Marine Strategy Framework Directive.

This study aims to detect how many microplastics and what kind are released from the wastewater treatment plant (WWTP) Skebäck, in Örebro. The study was limited to the analysis of three filters with 50 μm mesh size and one filter with 300 μm mesh size. The samples were taken at different times, two in the fall of 2019 and one in the spring of 2020. Visual characterization was used for the quantification of microplastics, and a lower and upper bound was used. The lower bound represents particles that were deemed identifiable as plastic with high certainty, while the upper bound also includes particles that may have been microplastic. An additional ATR-FTIR analysis was performed on selected microplastics >300 μm.  The presence of microplastics in the effluent from Skebäcks WWTP could be confirmed. The quantity of microplastics per m​3​ (MP/m​3​) trapped on the 50 μm filters were quantified in a range between 0 MP/m​3​ to 291 MP/m​3​ for the lower bound, and 72 MP/m​3​ to 435 MP/m​3​ for the upper bound. The 300 μm filter had considerably less microplastics than the 50 μm filter with 1.8 MP/m​3​. The quantification of fibers on the 50 μm filter and 300 μm filters was not possible due to high blank contaminations. According to the concentration of 63 MP/m​3​ of the lower bound count on the 50 μm filters and the amount of water flowing through Skebäck in 2019, 17 818 935 m​3​, 1.1 billion microplastic particles were released into Svartån that year. In comparison the highest value of the upper bound count, 435 MP/m​3​, gave a release of 7.7 billion microplastic particles. Using the concentration of the 300 μm filter 1.8 MP/m​3​, 32 million microplastics/year were released from Skebäck in 2019. The amount of spheres 50-300 μm released in the effluent from Skebäck was estimated to be 3.7 kg in 2019.

Microplastics are emerging pollutants in the marine environment, including a range of polymers modified by varying quantities of additives and sorbed pollutants, differing in size, colour, and shape. This study focuses on characterization and quantification through visual characterization of microplastics >300 μm in surface water and at 5-meter depth in the Gulf of Bothnia. A comparison between a reference area and an urban impact area was made to estimate if the water is more polluted near rural or industrial areas. The visual characterization was based on general guidelines provided by GESAMP to minimize the risks of identifying false positives. The concentrations of microplastics were found to be similar in the current study in comparison to other studies in the Baltic Sea. There was insufficient evidence to conclude a difference between the reference area and the urban impact area. A key finding in this study was that fragments, i.e. irregular shaped hard particles having appearance of being broken down from a larger piece of litter were the most abundant type of microplastics particles found. The vast majority of the identified polymers by ATR-FTIR (Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy) consisted of Polyethylene (PE) and Polystyrene (PS)

Microplastics represent persistent and highly dispersal pollutants in the marine environment. The knowledge about ingestion and relative effects in large marine vertebrates, such as sea turtles, is still fragmentary. To date, studies on MP accumulation in these animals were based on the analysis of gastrointestinal tracts obtained after necropsy. In this study, we developed a protocol that allows the study of the MP through faecal material from alive turtles, that can be used in rescue centres in several locations. Specifically, faecal samples from 45 specimens of Caretta caretta, rescued along the coast of Emilia-Romagna and Marche (Italy) from 2016 to 2019 were assessed for MP content through different hospitalization periods. A unique sample was collected from 24 animals, while for 21 specimens two samples were obtained. This allowed us to quantify and characterize the MPs and to evaluate putative differences in the excreted particles during the hospitalization period. All individuals showed MPs in the faeces, for an average value of 6 ± 6.09 particles/animal. The maximum number of particles found in a single individual is 34 MPs. Filamentous particles were the most represented shape and transparent/white and red colours prevailed over the other colours. Analyses of data about first sampling show a significant negative correlation between MP number and turtle’s size. This could be due to the different feeding behaviours that occur in these animals according to their life stage. The absence of significant differences between classes and categories of shape and colours particles could be due to the high contamination of the preys in the Adriatic Sea. The absence of significant differences between the first and second sampling (where available), suggests that during the hospitalization period there might have been external influences that affected the results, including MP intake with diet, which would be considered in future studies.

Microplastics have been found in all aquatic environments and once they entered they cannot be removed. This has put new focus on the sources of microplastics where the textile industry has gained large attention. Much consideration has been given to the production of fleece fabric and the use of polyester but this report aims to explore the whole design- and production process and mapping those activities which has a large impact on microplastic release. Together with participants from five (5) Swedish Outdoor Brands and seven (7) field experts has this report mapped possible challenges and solutions. Main findings are 20 different challenging areas with 19 suggested solutions on how to prevent microplastic pollution. The result is the first in its kind doing a comprehensive study of the whole textile design- and production process and provides a broad foundation for further research. As there still is a considerable lack of knowledge about many of the issues that were brought up, both within the design- and production processes, has a shared responsibility among companies, organizations, universities and private persons been raised. Through common platforms are inspiration and awareness spread and this report aims to contribute to the gap in the current knowledge.

La pollution plastique est aujourd'hui une préoccupation environnementale et sociétale majeure. Au cours des 10 dernières années, de nombreuses études expérimentales ont complété les observations de terrain dans l’espoir de mieux comprendre le devenir et l’impact des micro et / ou nano-plastiques (MP / NP) sur divers organismes (par exemple: oiseaux, poissons et mammifères). Chez les poissons, les effets les plus significatifs reportés après une exposition aux MP/NP ont été observés sur les fonctions comportementales et neurologiques, la perméabilité intestinale, le métabolisme et la diversité du microbiome intestinal. Cependant, la pollution plastique reste difficile à quantifier dans l'environnement et à contrôler en laboratoire, et les particules de plastique sont souvent co-contaminées de manière naturelle ou expérimentale avec divers polluants chimiques. Par conséquent, les études sur les effets comportementaux et physiologiques associés à l’ingestion des MP/NP vierges chez les jeunes stades de vie poissons marins restent peu nombreuses à l’heure actuelle. Ainsi, l’objectif de cette thèse est d’étudier les effets de deux types de plastique fréquemment rencontrés en milieu marin, à savoir le polyéthylène (PE) et le polystyrène (PS), sous la forme de microplastiques (de 10 à 100 µm), sur les jeunes stades de vie des poissons marins, connus pour être particulièrement sensibles aux stress environnementaux. Ainsi, des larves et juvéniles de différentes espèces de poissons modèles (Tropicale : Acanthurus triostegus et Tempérée : Sparus Aurata) ont été sélectionnés. Plusieurs paramètres physiologiques et comportementaux ont été étudiés après une exposition à des microplastiques via différentes voies (eau et nourriture) dans le cadre de diverses expériences sur ces espèces modèles. Les résultats actuels ne montrent pas d’effets marqués de ce stress à des doses environnementales, cependant certains résultats, comme une augmentation de la mortalité et des perturbations métaboliques, à des doses plus élevées, semblent montrer une toxicité suite à l’ingestion de ces particules. Ainsi, cette thèse révèle que la toxicité des MP / NP vierges sur les poissons devrait être évaluée plus systématiquement en utilisant des méthodes rigoureuses en laboratoire, dans le but d’acquérir une meilleure compréhension des mécanismes sous-jacents de cette toxicité chez les poissons
Environmental plastic pollution is a major ecological and societal concern today. Over the last 10 years, a broad range of laboratory and experimental studies have complemented field observations in the hope of achieving a better understanding of the fate and impact of micro- and/or nano-plastics (MP/NP) on diverse organisms (e.g. birds, fish and mammals). However, plastic pollution remains challenging to monitor in the environment and to control under laboratory conditions, and plastic particles are often naturally or experimentally co-contaminated with diverse chemical pollutants. In fish, the most significant effects reported after exposure to MP / NP were observed on behavioral and neurological functions, intestinal permeability, metabolism and intestinal microbiome diversity. However, plastic pollution remains difficult to quantify in the environment and to control in the laboratory, and plastic particles are often co-contaminated naturally or experimentally with various chemical pollutants. Therefore, studies on the behavioral and physiological effects associated with ingestion of virgin MP / NP in early life stages of marine fish are still few at present. Thus, the purpose of this thesis is to study the effects of two types of plastic frequently encountered in the marine environment, namely polyethylene (PE) and polystyrene (PS), in the form of microplastics (from 10 to 100 μm), on the early life stages of marine fish, known to be particularly sensitive to environmental stresses. Thus, larvae and juveniles of different model fish species (Tropical: Acanthurus triostegus and Temperate: Sparus Aurata) were selected. Several physiological and behavioral parameters were studied after exposure to MP via different pathways (water and food) in various experiments on these model species. Current results do not show any marked effects of this stressor at environmental concentrations, however some results, such as increased mortality and metabolic disturbances, at higher doses, show toxicity following ingestion of these particles. Thus, this thesis reveals that the toxicity of virgin PM / NP on fish should be evaluated more systematically using rigorous laboratory methods, in order to gain a better understanding of the underlying mechanisms of this toxicity to fish

Plastic, including microplastic, is a common product in the society today and is starting to be more common in oceans where it can stay for a long time. Microplastic is defined usually in the size range five millimeter and smaller and together with the important Chao Phraya river in Bangkok, Thailand, the main subject of this paper is described. More clearly, the aim of this paper is to provide a first-hand quantification of microplastics flowing into the Chao Phraya River. Samples were taken at upstream, middle and downstream locations in the river with a pump-system and were then analyzed in a lab. The result showed an increasing load of microplastic entering the river from Bangkok, for example the result for size range five to one millimeter showed a six times increase of microplastic between the upstream and downstream point.
Plast, däribland mikroplaster, är en vanlig förekommande produkt i samhället idag och börjar bli allt vanligare i hav där det också kan stanna ett långt tag efter att det hamnat där. Mikroplaster definieras oftast med storleks intervallet fem millimeter och mindre och tillsammans med den viktiga floden Chao Phraya i Bangkok, Thailand, är huvudämnet för denna studie beskriven. Mer tydligt, målet för denna studie är att förse en första kvantifiering av mikroplaster som flödar in till Chao Phraya floden. Prover togs på platser som var uppströms, i mitten och nedströms på floden och sedan analyserades dessa prover i ett laboratorium. Resultatet som framkom visade på ökande belastning av mikroplaster i floden från Bangkok, exempelvis visade resultatet för storleks intervallet fem till en millimeter på en sex gånger ökning av mikroplaster mellan uppströms platsen och nedströms platsen. Ökningen som troligen kommer från innerstaden kan bero på olika faktorer såsom väder, stadens avfallshantering och användningen av engångsprodukter som är av plastmaterial. Således påvisar detta vikten av, bland annat, en fungerande avfallshantering.

Neste trabalho foram analisados sedimentos marinhos de três praias da Baía de Guanabara (praia de São Bento e praia da Bica, na Ilha do Governador, e praia de São Francisco, em Niterói), Rio de Janeiro, para avaliar a presença de microplásticos (fragmentos plásticos com tamanho ≤ 5 mm) nestes ambientes. Os detritos plásticos visíveis (macroplástico) foram separados dos sedimentos manualmente e pesados. Os detritos plásticos não visíveis foram separados por densidade com solução saturada de cloreto de sódio. Os fragmentos plásticos obtidos com a separação por densidade foram caracterizados por microscopia óptica para avaliar forma e superfície, e foram classificados e quantificados em função de seu tamanho. Os fragmentos microplásticos foram separados e caracterizados por espectrometria de absorção na região do infravermelho por reflexão atenuada (ATR FT IR). Os espectros obtidos foram comparados com espectros padrão de polímeros. As três praias se apresentam contaminadas com lixo macroplástico e com lixo microplástico. Na praia da Bica, foram coletados 173 fragmentos, dos quais 73% são microplásticos. Na praia de São Bento foram 81 fragmentos e na praia de São Francisco foram 73 fragmentos, dos quais 70% e 86%, respectivamente, são microplásticos. Nas três praias foram encontrados fragmentos microplásticos de poliestireno expandido. Nas praias da Bica e de São Bento foram encontrados fragmentos de polietileno; nas praias de São Bento e São Francisco foram encontrados fragmentos microplásticos de polipropileno. O descarte irregular de lixo e atividades industriais e comerciais no entorno da baía podem ser apontados como possíveis fontes contaminantes
In this study samples of sediment of three beaches of Guanabara Bay, Rio de Janeiro, (São Bento beach and Bica beach, in Ilha do Governador and São Francisco beach, in Niterói) were analyzed to investigate the contamination with microplastics (plastic fragments ≤ 5 mm). Samples of sediment were examined by naked eye to sort items of plastic debris from other materials. After separation plastic items were weighted. Non visible plastic debris were separated from sediments by density difference applying a concentrated saline NaCℓ solution. Plastic fragments picked up from supernatant were characterized by optical microscopy to analyze morphology and classified in size fractions. From sediments of Bica beach were collected 173 plastic fragments and 73% of them were microplastic. In São Bento beach were collected 81 fragments and in São Francisco beach were collected 73 fragments, from which 70% and 86%, respectively, were microplastic. The three beaches are contaminated with both microplastic and macroplastic. Microplastic fragments were characterized by ATR FT IR. Expanded polystyrene microplastic fragments were found in sediments of the three beaches. Polyethylene microplastic fragments were found in sediments of Bica and São Bento beaches and polypropylene microplastic fragments were found in sediments of São Bento and São Francisco beaches. Littering, illegal-dumping and industrial activities are possible sources of microplastic contamination of Guanabara Bay

Atualmente, a poluição marinha por microplásticos é uma grande preocupação ambiental, considerando principalmente a capacidade de dispersão e resistência à degradação que estes materiais possuem. A matéria prima plástica é normalmente comercializada na forma de \"pellets\", grânulos com cerca de 5 mm de diâmetro, que são encontrados em ambientes marinhos e costeiros de todo mundo, inclusive do Brasil. Estes podem ser perdidos nas etapas pré-consumo da cadeia produtiva dos plásticos e chegar direta ou indiretamente ao mar. Embora possam causar impactos ambientais e, eventualmente à saúde humana, há poucos registros formais sobre suas fontes. Assim, o presente projeto configura-se como um estudo para o entendimento da origem e de possíveis soluções para esta questão, a medida em que objetiva mapear e entender os diferentes processos de perda destes microplásticos para o meio ambiente, visando o desenvolvimento de orientações capazes de levar à redução desta perda. As conclusões apontam que as soluções para o problema passam por uma articulação multissetorial e definição de diretrizes para reduzir a perda adequadas à realidade brasileira. Estas diretrizes devem ser implementadas por meio de políticas públicas e instrumentos de comando e controle, que preferencialmente devem estar associados a mecanismos de regulação de mercado. Para efetivação destas políticas torna-se necessário ainda um enquadramento dos pellets como poluentes.
Currently, the plastic and microplastic marine pollution is a major environmental concern considering the difficulty in dealing with the dispersal capacity and resistance to degradation of these materials. The plastic material is usually marketed as plastic pellets, granules of about 5 mm of diameter, which are found in marine and coastal environments worldwide, including in Brazil. Possibly due to losses on the pre-consumer stages of production - on pellets producers, transporters and/or processors - arriving directly to the sea or indirectly by rivers and urban run-off. Although they can cause impacts to environment and, eventually, to human health, there are few formal records of its occurrence and its sources, essential information for managing this issue. Thus, this project is configured as a strategic study for understanding the origin and possible solutions for this issue. The main objective is to map and understand the different processes of these microplastics loss to the environment, aiming the development of guidelines to reduce this loss. The results indicate that the solutions to the problem undergo a multi-sectoral articulation and definition of appropriate guidelines to reduce the loss in the Brazilian reality. These guidelines should be implemented through public policies and instruments of command and control, which should preferably be associated with mechanisms of market regulation. In order to these changes take effect it is needed a clear framing of lost plastic pellets as pollutants.

Plastic debris is an emerging environmental issue, with >10 million tons of plastics debris per annum entering the sea. Exposure to marine conditions facilitates the exponential fragmentation of plastic to micro-sized particles (microplastics). Marine and coastal sediments are a sink for microplastic pollution. Consequently, the ingestion of microplastics by a range of benthic marine invertebrates, including polychaete worms, has been reported in situ. Microplastics are vectors for priority pollutants capable of eliciting adverse health effects. However, the particle and chemical toxicity which microplastics could incur to ecologically-important marine invertebrates is unknown. This thesis aims to determine the potential for microplastics to cause harm in the marine environment, with a focus on benthic polychaete worms. Specifically, it assesses the potential particle toxicity which could arise from chemical-free microplastics; and the potential chemical toxicity which could arise from leached endogenous chemical additives or sorbed chemical pollutants. To address these, an integrative approach was employed, primarily using laboratory-based whole-sediment in vivo exposures, established cellular and whole-tissue toxicity assays, and analytical chemistry. For the first time, this thesis reports that chemical-free microplastics cause particle toxicity in the lugworm Arenicola marina. Feeding activity was reduced during exposure to 5% microscopic unplasticised polyvinylchloride (UPVC) by sediment weight, whilst exposure to ≥1% UPVC by sediment weight significantly reduced energy reserves relative to control animals. Evidence for the transfer and toxicity of endogenous additives from PVC to lugworms is provided. Lugworms exposed to 1% PVC by sediment weight exhibited a 70% increase in additive concentration, coinciding with inhibited mucus production and enhanced lipid reserves and oxygen consumption, compared to control lugworms. Ragworms (Hediste diversicolor) exposed to leached toxicants from bioplastic cigarette debris were found to exhibit significantly longer burrowing times, >30% weight loss, and >2-fold increase in DNA damage compared to control ragworms. Bio-concentration factors for nicotine – the biomarker of exposure - were 500 fold higher from leachates in seawater than from microfibres in sediment. Overall, this thesis provides evidence to suggest that the incorporation of microplastics into marine sediments can significantly impact the health of marine polychaete worms due to both particle and chemical effects. This emphasises the need to reconsider the classification of plastic as non-hazardous and questions whether we as humans are also at risk.

La production de plastique est en augmentation continue pour répondre à la forte demande mondiale. Cette production massive est la source d'importantes quantités de plastiques que l'on retrouve dans les milieux aquatiques. Parmi ces plastiques, les microplastiques (MP) (particules microscopiques d’une taille < 5 mm) se retrouvent dans l’eau, les sédiments et sont susceptibles d’être ingérés par divers organismes marins. Cette thèse se focalise sur (1) l’évaluation des sources et des apports de microplastiques au milieu aquatique et de leur présence dans les organismes, et (2) de tester la faisabilité d’utiliser des organismes vivants pour la surveillance de la pollution de l’environnement par les microplastiques. Deux zones côtières affectées par des pressions anthropogéniques ont été étudiées : Le Havre et le littoral libanais. Dans le premier cas, le rôle d’une station de traitement des eaux usées (STEP) et d’une décharge côtière dans l’introduction des microplastiques dans l’environnement a été étudié. Les MPs ont d’abord été analysés dans l'influent, la boue et l’effluent de la STEP. Leur devenir a été suivi selon un gradient de distance de la STEP au niveau de trois matrices : eau de surface, sédiments et moules sauvages (Mytilus spp.). Les MPs ont été trouvés au niveau de toutes les matrices avec une concentration qui diminue en s’éloignant de l’effluent. Des taux de microplastiques élevés (plus élevés que ceux trouvés à côté de la STEP) ont été observés à proximité de la décharge côtière, suggérant son rôle important comme voie d’entrée des MPs dans les eaux côtières. Le long de la côte libanaise, nous avons évalué pour la première fois la pollution par les MPs dans l'eau de mer, les sédiments et dans deux espèces marines importantes en terme de consommation humaine (un poisson pélagique: Engraulis encrasicolus et un bivalve: Spondylus spinosus). Les résultats ont montré différents patterns de concentration des MPs dans les matrices analysées. La présence de MPs dans les organismes était élevée (83.4% et 86.3% dans les anchois et les huîtres, respectivement). Ces résultats ont mis en évidence la pollution élevée liée aux MPs au niveau du bassin Levantin par rapport aux autres régions de la Méditerranée occidentale. De plus, les résultats obtenus indiquent une contribution potentielle des décharges côtières à cette pollution. Le plus souvent, les études sur les microplastiques impliquent l'échantillonnage d’organismes indigènes. Au cours de cette thèse, nous avons testé la faisabilité d'utiliser des organismes transplantés (encagement) pour évaluer la pollution par les microplastiques dans l'environnement marin côtier. Nous avons mis au point des expériences d'encagement avec des juvéniles de flets, Platichthys flesus, en estuaires et des moules bleues, Mytilus edulis, en zone côtière. Pour chaque espèce, l'abondance et les caractéristiques (forme, taille, couleur et type de polymères) des MPs ingérés par les individus encagés ont été comparées avec les MPs ingérés par des individus sauvages capturés sur le même site et avec ceux trouvés dans leur environnement (eaux de surface et sédiments). Nos résultats suggèrent que la technique d'encagement d'organismes peut constituer un outil prometteur pour la biosurveillance des MPs la rendant plus fiable et permettant une étude précise des effets biologiques des MPs sur une période d'exposition prédéterminée
Plastic fabrication is increasing worldwide in response to daily human demands. This mass production is linked to the immense plastic marine litter found all around the world: each synthetic material is meant to find its way back into the aquatic systems. Anthropogenic pressure and the immense human population, the lack of appropriate plastic treatment process and the growing industrial activities advocate their presence in the aquatic environments. These plastics are then found in the form of microplastics (microscopic particle with a size < 5 mm) observed in the water, in the sediments and are prone to be ingested by various marine organisms along the trophic chain. This thesis focuses on (1) assessing microplastics sources and input into the aquatic environment and their occurrence in biota, and (2) to test the feasibility of using transplanted organisms (caging) for monitoring microplastics pollution in the marine coastal environment. Two coastal areas highly impacted by anthropogenic pressures were studied: Le Havre in France and the Lebanese coast. For the former, the role of a municipal wastewater treatment plant (WWTP) effluent and an abandoned coastal landfill as pathways for microplastics (MPs) input into the marine environment was assessed. MPs were first analyzed in raw sewage influent, sludge and effluent samples, and their fate was studied along a distance gradient from the WWTP in three matrices: surface water, sediments and wild mussels (Mytilus spp). MPs were found in all matrices with a decreasing abundance from the effluent. Strong MPs abundances (higher than those found near the WWTP effluent) were observed in the vicinity of the coastal landfill suggesting its importance as a MPs entry route into the marine coastal environment. Whereas for the Lebanese coast, we evaluated for the first time the MPs pollution in the seawater, sediments and two important seafood species (one pelagic fish: Engraulis encrasicolus and one bivalve: Spondylus spinosus). Results showed different patterns of MPs concentration in the analyzed matrices. The occurrence of MPs in the biota was high (83.4% and 86.3% in anchovies and spiny oysters, respectively). These results highlighted the high MPs pollution found in the Levantine Basin in comparison to other Western Mediterranean regions. In addition, the obtained results indicate the potential contribution of coastal landfills to this pollution. Most often microplastics studies involve collection of organisms’ samples from natural populations. In this thesis, we tested the feasibility of using transplanted organisms (caging) for monitoring microplastics’ pollution in the marine coastal environment. We developed caging experiments with juvenile European Flounder, Platichthys flesus, in estuarine nursery grounds and blue mussels, Mytilus edulis, in coastal marine environment. For each species, the abundance and characteristics (shape, size, color and type of polymers) of MPs ingested by caged individuals are compared with those ingested by wild individuals collected at the same site and with those found in their surrounding environment (surface water and sediments). Our results suggest that transplanted organisms (caging) may be a promising tool for MPs biomonitoring making monitoring more reliable with an accurate assessment of the biological effects of MPs over a predetermined exposure period

In recent decades, global plastics production and consumption have continued to increase. Although many policy strategies on waste prevention and recycling have been implemented, much of the plastic waste is dispersed in nature. In general, the presence of waste in the aquatic environment is a serious environmental problem, well known as marine waste, and is responsible for environmental, economic, health and aesthetic problems at the ocean and regional level and the dominant category of waste is plastics. Due to their chemical persistence, buoyancy and increased sources, plastic objects and their fragments (known as "microplastics" (MPLs) and "nanoplastics" (NPLs)) are omnipresent in the marine environment, especially in closed basins such as the Mediterranean Sea. Nowadays, given the increasing levels of plastic pollution in marine environments, MPL/NPL are considered emerging pollutants that can pose a serious threat to marine ecology and human health. Despite constant scientific progress, large gaps in knowledge about the fate, distribution, behaviour and effects of MPLs/NPLs have not yet been filled. In this context, this thesis aimed to expand knowledge on plastic pollution in coastal environments. In particular, the first part of the study focused on the river transport of plastics and the fate and behaviour of MPLs/NPLs in estuaries and coastal waters. The results of one year of visual observations of floating anthropogenic macro-litters (> 2.5 cm) of the Llobregat and Besòs Rivers showed that the Barcelona metropolitan area contributes substantially to marine pollution. Large quantities of plastic (mainly single-use goods) were transported from these rivers to the western Mediterranean Sea. Given the significant contribution of plastic waste from rivers, valuable information can be obtained by assessing the spatial distribution of MPLs/NPLs in estuarine environments. To perform these studies, several analytical techniques based on mass spectrometry (MALDI-TOF/MS, DART-MS, and LC-APPI-HRMS) were compared for the quantitative analysis of MPLs/NPLs in water samples. The best results in terms of sensitivity were obtained with dimensional exclusion-LC coupled with APPI-QExactive. Consequently, a new LC-HRMS method was optimized, validated and finally applied to assess the presence of PS in natural water samples from the Ebro Delta (Catalonia, Spain). The results reported the highest concentrations along the river near urban areas and in the bay where important commercial fishing activities are established. In addition to plastic pollution, estuaries can be highly contaminated with persistent organic pollutants, especially from wastewater. Since MPLs may also be responsible for the transport and distribution of pollutants, the absorption behaviour of MPLs with perfluoroalkylated substances (PFASs) in freshwater and seawater has been assessed. An increase in adsorption capacity was observed in this order PS>PS-COOH>PE. As demonstrated by these results, the plastic pollution of coastal ecosystems, from macro to nano, is a real problem that can lead to serious damage to both nature and society. To protect the coastal environment, its productivity and humans, it is necessary to assess the ecotoxicological impacts on marine organisms and human health. In this regard, a new digestion approach has been developed to determine the presence of MPLs in the gastrointestinal tracts of a sentinel species in the Western Mediterranean. The high frequency of plastics and the types of polymers reported in this study confirmed the negative impacts of local fishing gear. Although the ingestion of MPLs by marine organisms is a widely recognised effect of marine plastic waste, very limited data are available on the impact of MPLs, and especially NPLs, on human health. Therefore, cytotoxic effects at the cellular level after exposure to moderate concentrations of PS and PE particles of nanometric size have been assessed. Significant results were reported only at high concentrations of PS. In conclusion, the work presented in this thesis has successfully filled some of the various gaps in knowledge about plastic pollution and its effects. In the future, further tools should be promoted to facilitate the overall analysis of smaller MPLs, including NPLs.
Los plásticos han desempeñado un papel importante en el desarrollo tecnológico e industrial, mejorando la calidad de la vida humana, pero, el uso excesivo y mala gestión de los desechos han dado lugar a la acumulación de residuos plásticos en el medio ambiente. Debido a su persistencia, los desechos plásticos se encuentran presentes en diferentes compartimentos ambientales como ya ha sido señalado en varios estudios, donde la mayor preocupación se centra en las partículas de tamaño más pequeño. Hoy en día, los micro(nano)plásticos se consideran contaminantes peligrosos que pueden causar graves daños al medio ambiente y la salud humana. Es por ello que se debe profundizar en la evaluación química y ecotoxicológica de los micro(nano)plásticos y los riesgos emergentes. La investigación científica ha promovido numerosas iniciativas para evaluar la presencia, destino e impacto ambiental de estos contaminantes en el medio acuático, especialmente en los medios marinos. En este contexto, los objetivos generales de esta tesis doctoral se enfocaron en estudios integrados de la presencia y destino de la contaminación plástica en el medio ambiente costero, especialmente en el transporte fluvial de macroplásticos en la zona de Barcelona y el destino/comportamiento de las micro(nano)partículas de plástico en las aguas estuarinas y costeras del noroeste del Mar Mediterráneo. Para ello, se desarrollaron métodos analíticos para cuantificar e identificar el comportamiento de estos compuestos y sus co-contaminantes en el medio ambiente. Los resultados demostraron una contribución significativa de desechos plásticos provenientes de los ríos. En particular, para el análisis de micro(nano)plásticos en agua, se desarrolló un método con exclusión dimensional-LC acoplada con APPI-QExactive que permitió cuantificar la presencia de poliestireno (PS) en muestras de agua del Delta del Ebro (Cataluña, España). Posteriormente, se realizó un estudio de adsorción de sustancias perfluoroalquiladas en la superficie de los microplásticos donde se observó un aumento de la capacidad de adsorción de PS>PS-COOH> polietileno. Por último, se evaluaron las consecuencias ecotoxicológicas de los micro(nano)plásticos en el medio ambiente y la salud humana. Se confirmó una alta frecuencia de plásticos en una especie centinela del Mediterráneo, producto de los aparejos de pesca locales. Finalmente, los efectos citotóxicos de los PS-nanoplásticos han sido comprobados por estudios toxicológicos en células humanas.

Le risque environnemental lié à la présence de plastiques dans les milieux aquatiques a été suggéré, pour le milieu marin, dès les années 1970. Même s’il reste incomplètement cerné (d’un point de vue écotoxicologique essentiellement), il ressort de la littérature qu’il est significatif. Même si certains travaux suggèrent qu’une grande partie de ces plastiques provient des eaux continentales, il n’existe aujourd’hui peu d’étude sur les niveaux d’imprégnation des milieux aquatiques en milieu continental et aucune à l’échelle des bassins versants urbains pour préciser l’importance des différentes sources urbaines.Dans cette étude, les macroplastiques (> 5 mm) ainsi que les microplastiques (<5 mm) sont considérés. Les flux de macroplastiques dans la Seine ont été estimés à l’aide d’une étude de terrain mais aussi à l’aide d’une approche théorique. En ce qui concerne les microplastics, les fibres (synthétiques et artificielles) ainsi que les fragments ont été étudiés dans différent compartiments du système urbain. L’air intérieur, les retombées atmosphériques, les eaux de ruissellement, les effluents et affluents de stations d’épuration ainsi que les rejets urbains en temps de pluie ont été étudiés.Les concentrations en microplastiques dans le milieu récepteur ont aussi été estimées. Le suivi de la contamination des eaux de surface a été abordé selon deux méthodes d’échantillonnage distinctes : échantillonnage par un filet avec une maille de 80 μm et par un filet de 330 µm. L’homogénéité des fibres le long de la section a aussi été estimée, tout comme la variabilité temporelle à court terme. Pour finir, un suivi mensuel sur 19 mois a été effectué en amont et en aval de Paris.Cette étude a permis de montrer que les flux de microplastiques dans la Seine représentent une masse négligeable par rapport aux flux de macroplastiques. Elle confirme aussi l’ubiquité des fibres dans tous les compartiments. Les fragments sont quant à eux particulièrement concentrés dans les rejets urbains en temps de pluie. Pour la première fois, il a été montré que le compartiment atmosphérique jouait un rôle potentiellement important, autant que source de microplastiques
Plastic pollution has been widely studied in marine environment since 1972 and mostly since 2004. Investigations on plastic pollution in freshwater and especially in urban catchments just started at the beginning of the decade, and urban plastic pollution sources and its related fluxes in rivers remains mainly unknown. Thus a specific attention should be paid to the plastic contamination in catchments exposed to severe anthropogenic pressure, especially within the urban areas. This PhD thesis focuses on the case of the Paris agglomeration and its impact on the Seine River. A double approach was carried out as both macro- (>5mm) and micro- (<5mm) plastics were considered.The amount of macroplastics conveyed by the Seine River was estimated with a field study and with a theoretical approach.Regarding microplastics, fibers (made with synthetic but also man-made polymers) and fragments were both investigated in different compartments of the urban system. The study focused on the air compartment (indoor and outdoor air as well as atmospheric fallout), the sewer system (from the washing machine disposals to the WWTP influents and effluents), and the inputs during wet weathers periods, i.e, runoff and combined sewer overflows. Fibers and fragments were also examined on the Seine River.This work aimed at providing relevant methodological keys to address sampling of microplastic in rivers. Two mesh size nets were tested (80 µm vs. 300 µm). The homogeneity of fibers distribution in rivers was also verified as the short term temporal and spatial variabilities were evaluated. In order to highlight the potential impact of the Paris agglomeration, a monthly monitoring on 5 sites upstream and downstream Paris was carried out as well.This thesis mainly highlighted the ubiquity of fibers in all compartments. Fibers were predominant in comparison to fragments in all compartments. Combined sewer overflows exhibited particularly high amounts of fragments. On the other hand, the flux of microplastics in the Seine River was proved be negligible in terms of mass in comparison to macroplastics. This study is also the first one showing that the atmospheric compartment needs to be considered as a potential significant source of microplastics

La pollution plastique océanique est l’une préoccupation majeure de notre siècle, avec plusieurs millions de tonnes de plastique déversées dans l'océan chaque année qui menacent la santé des écosystèmes. Les effets des plastiques ont été identifiés à tous les niveaux de la chaîne trophique, du zooplancton à la mégafaune, mais leurs effets sur la vie des microorganismes et sur leur rôle crucial dans le fonctionnement de l'écosystème océanique restent méconnus. L'objectif de cette thèse était d'étudier l'écotoxicité des plastiques en milieu marin. La première question traitée était : dans quelle mesure l'abondance, la diversité et l'activité de la vie bactérienne se développant sur le plastique, nommée «plastisphère», sont influencées par les propriétés chimiques du polymère et les changements environnementaux (chapitre 2)? Ce point a été abordé en immergeant pendant 2 mois dans l'eau de mer du Polyéthylène (PE), de l’acide polylactide (PLA) ainsi que du verre comme témoin, sous différentes formes : méso-débris (18 mm de diamètre), grands microplastiques (LMP; 3 mm de diamètre), et petits microplastiques (SMP; de 100 µm de diamètre de formes sphériques et irrégulières). Nous avons constaté que la composition chimique du plastique, les phases successives de formation du biofilm et les interactions phytoplancton-bactéries étaient des facteurs déterminants de l'abondance, de la diversité et de l'activité de la plastisphère a contrario de la taille et à la forme du matériau.La deuxième question traitée était : le microplastique (polystyrène PS; 50-100 µm; trois concentrations) ainsi que leur biofilm mature seraient-ils toxiques pour le filtre-filtreur marin Branchiostoma lanceolatum et dans quelles mesures la plastisphère peut-elle influencer cette toxicité (chapitre 3)? Nous avons utilisé un large éventail de techniques complémentaires pour suivre l'ingestion des microplastiques (quantification microscopique) à l’origine d’une potentielle modification du microbiote intestinal de l’hôte (séquençage 16S rRNA Illumina Miseq). La réponse physiologique de l’hôte a également été suivie au travers de l’expression génique du système immunitaire, du stress oxydatif et de l’apoptose (Nanostring) ainsi que par histopathologie ( La microscopie électronique à transmission). Aucune toxicité évidente n'a été observée, alors que les microplastiques pourraient être un vecteur de modification du microbiome intestinal, et qu’une plus grande différenciation des cellules a été observée au niveau des tissus intestinaux. La troisième question traitée était: Existe-t-il des alternatives aux microbilles pétrochimiques conventionnels utilisées en cosmétique biodégradables en milieu marin? (Chapitre 4). Nous avons utilisé une approche multidisciplinaire pour suivre les 4 étapes de biodégradation dont la 1/biodétérioration (granulométrie, gravimétrie et spectroscopie FTIR), 2/la biofragmentation (chromatographie d'exclusion de taille, résonance magnétique nucléaire 1H et spectrométrie de masse à haute résolution), 3/la bioassimilation et 4/la minéralisation (résonance magnétique nucléaire 1H et mesures de l'oxygène) sur différentes formes de microbilles en présence de bactéries marines. Après 60 jours d’incubation, nos résultats ont permis d’identifier des microbilles de polyhydroxybutyrate-co-hydroxyvalérate (PHBV) ou de riz et dans une moindre mesure de polycaprolactone (PCL) et d'abricot comme alternatives aux microplastiques conventionnels, en PE ou en polyméthacrylate de méthyle (PMMA) non biodégradés dans nos conditions. Fait remarquable, le PLA biosourcé n'était pas biodégradable, mais le PCL pétrochimique était biodégradable dans nos conditions marines
Oceanic plastic pollution is of major concern, with several million tons of plastic dumped in the ocean every year that are causing health threat to marine creatures. Impacts have been found at all the trophic chain levels from the zooplankton to the megafauna, but little is known on its impact on the microbial life and its crucial role in the oceanic ecosystem functioning. The objective of this thesis was to study the ecotoxicity of plastics in the marine environment. The first handled question was: how much the abundance, diversity and activity of bacterial life growing on plastic, i.e. the ‘plastisphere’ are driven by the chemical properties of the polymer and the environmental changes (Chapter 2)? Polyethylene (PE) and polylactide acid (PLA) together with glass controls in the forms of meso-debris (18mm diameter) and large-microplastics (LMP; 3mm diameter), as well as small-microplastics (SMP; of 100 m diameter with spherical and irregular shapes) were immerged during 2 months in seawater. We found that the plastic chemical composition, the successive phases of biofilm formation and the phytoplankton-bacteria interactions were more important factors driving the abundance, diversity and activity of the plastisphere as compared to material size and shape. The second handled question was: would the microplastic (polystyrene PS; 50-100 µm; three concentrations) together with their mature biofilm be toxic for the marine filter-feeder Branchiostoma lanceolatum and how much the plastisphere can influence this toxicity (Chapter 3)? We used a large set of complementary techniques to follow the microplastic ingestion (microscopy quantification) and the modification of the gut microbiota (16S rRNA Illumina Miseq sequencing), the gene expression of immune system, oxidative stress and apoptosis (Nanostring) and also histopathology (transmission electron microscopy). No obvious toxicity was observed, while microplastics could be a vector for bacteria to the gut microbiome, can induce more goblet cell differentiation and can surprisingly have a positive effect by supplying nutrients to amphioxus in the form of bacteria and diatoms from the plastisphere. The third handled question was: how much the conventional petroleum-based microbeads classically used in cosmetics can be substituted by other polymers for their biodegradability by the plastisphere in marine environment? (Chapter 4). We used complementary techniques to follow the 4 biodegradation steps including biodeterioration (granulometry, gravimetry and FTIR spectroscopy), biofragmentation (size exclusion chromatography, 1H nuclear magnetic resonance and high-resolution mass spectrometry), bioassimilation and mineralization (1H nuclear magnetic resonance and oxygen measurements). We concluded that microbeads made of polyhydroxybutyrate-co-hydroxyvalerate (PHBV) or rice and in a lesser extend polycaprolactone (PCL) and apricot were good candidates for substitution of conventional microplastics, classically made of PE or polymethyl methacrylate (PMMA) that were not biodegraded under our conditions. Interestingly, the biobased PLA was not biodegradable but the petroleum-based PCL was biodegradable under our marine conditions

Dentre as diferentes poluições presentes nos oceanos, o plástico é provavelmente, aquele que leva aos maiores impactos ambientais, sendo encontrado de praias e manguezais à giros no meio dos oceanos. Os macroplásticos, cujo tamanho é superior a 5mm, são maiores em volume e provocam um impacto socioambiental importante, porém os microplásticos, fragmentos menores que 5mm, estão em maior quantidade e podem provocar danos em organismos marinhos filtradores como mexilhões e ostras. Apesar da sua grande presença nos oceanos, ainda não se estabeleceu com clareza se causam efeitos somente físicos, por um aumento de material particulado não orgânico ingerido, ou se seus efeitos podem ser de origem química, devido à quantidade de contaminantes que possuem. Para estudar o impacto que essas partículas têm em organismos filtradores, o mexilhão Perna perna, espécie bioindicadora abundante na costa brasileira, foi exposto a partículas de polietileno encontradas em cosméticos nacionais. O microplástico foi adquirido diretamente da indústria e precisou ser identificado. A análise de FT−IR mostrou que o plástico era polietileno de baixa densidade. Os organismos então foram expostos ao polietileno, virgem ou lixiviado, em duas concentrações (0,5 g⁄L e 2,5 g⁄L) por diferentes períodos (12,24,48,96 e 144 horas). Após os experimentos, os mexilhões foram coletados e dissecados e a resposta de seis biomarcadores foi analisada: O Tempo de Retenção do Vermelho Neutro nos hemócitos, Danos ao DNA e Lipoperoxidação nas brânquias e os níveis de três proteínas de estresse (AIF−1, pP38−MAPK e HSP−70) nas glândulas digestivas. Todos os biomarcadores foram afetados pela exposição ao polietileno, porém um padrão no resultado não pôde ser observado. Os fatores de exposição analisados (Concentração, Período e Tratamento do Plástico) individualmente, ou combinados, levaram a respostas diferentes e até mesmo opostas em alguns casos. A coleta de indivíduos de P. perna in situ na região do Porto de Santos mostrou que todos os bancos naturais possuem organismos contaminados. Os resultados deste trabalho mostram que a fisiologia do mexilhão P. perna é modificada após a exposição aguda ao polietileno. Um maior número de biomarcadores deve ser analisado futuramente para elucidar quais vias estão efetivamente sendo ativadas ou inibidas. O alto nível de contaminação dos mexilhões da região do porto de Santos é um fator alarmante que deve ser discutido pela sociedade com o intuito de se criar soluções para o problema da poluição por plástico nos oceanos antes que este afete a saúde humana.
Among all different pollutants, plastic debris is one of the main environmental impacts, being found from beaches and mangrove to gyres in the middle of the oceans. Macroplastics, with size above 5mm, are larger in volume and are an important social and environmental problem, but microplastics, fragments less than 5mm can be most harmful for filter feeding animals such as mussels and oysters. However, it is still debatable if its effects are physical, due to the increase in indigestible material; or chemical, due to plastic additives such as phthalates or PCBs. To study the impact that these particles can have in those animals, the brown mussel Perna perna (Bivalvia) an abundant and an organism easy to maintain in the laboratory, was exposed to virgin or leached polyethylene (PE) microbeads, used as abrasives in Brazilian cosmetics. Polyethylene was acquired directly from the industry and therefore needed to be identified. Analysis of FT−IR showed that the plastic was Low Density Polyethylene. The microplastic exposure had two concentrations (0.5 and 2.5g⁄l) and different periods of time (12, 24, 48, 96 and 144 hours). After the experiment, the organisms were dissected and the levels of six biomarkers were analyzed: Neutral Red Retention Time by the Hemocytes, Lipid Peroxidation and DNA Damages in the Gills and the response levels of three stress proteins (pP38−MAPK, AIF−1 and HSP−70) in the Digestive Glands. All biomarkers were affected by the PE exposure, but the results did not follow a pattern. The exposure factors analyzed (Concentration, Period of Time and Plastic Treatment), alone or combined, led to different and sometimes opposite responses. In Situ collected samples in the Santos Harbour area showed that all natural mussel\'s beds analyzed had microplastics contaminated mussels. The results of this work showed that microplastics acute exposure in P. perna modifies its physiology. More biomarkers should be used to clarify which pathways are being activated or inhibited. The high levels of contamination of important commercial mussel\'s beds in the Santos Harbour area, is an alarming sign for the community, that should start working together to solve the plastic pollution problem in our oceans before starts to affect human health.

Há tempos a ubiquidade dos materiais plásticos no meio ambiente é assunto de discussão, com destaque para as partículas menores, ditas microplásticos (< 5 milímetros). Fibras provenientes de materiais têxteis são um subgrupo dos microplásticos e têm origem em diversas fontes, incluindo lavagens domesticas, uma vez que filtros de lavadoras e sistemas de tratamento de esgoto não são desenhados especificamente para retê-las. Quando no meio ambiente, estes materiais podem alcançar concentrações até milhares de unidades por metro cúbico, ficando disponíveis a uma gama de espécies. Neste cenário, o presente estudo teve como objetivo avaliar parâmetros de lavagem, e características têxteis que pudessem influenciar no desprendimento de fibras em efluentes de lavadoras domesticas. Foram realizados experimentos com dez sucessivas lavagens individuais, com e sem detergente, para quatro tipos de artigo: algodão (como padrão de comparação), acrílico, poliéster e poliamida. Os efluentes foram então filtrados (< 1 milímetro, 500 mícrons, 63 mícrons, 8 mícrons) e pesados. Resultados demonstram que todos os artigos têxteis liberaram fibras na lavagem. Dez sucessivas lavagens representaram queda na massa desprendida, bem como o uso de detergentes em comparação a lavagens sem detergente. Diferenças entre artigos sugeriram variação conforme características têxteis, onde algodão liberou mais fibras, seguido de acrílico, poliamida e poliéster. Em relação ao tamanho das fibras, a maioria ficou retida no filtro da lavadora (< 1 milímetro) e na peneira de 63 mícrons, mostrando o potencial de diminuição de porosidade do filtro. A visualização de fibras em papel-filtro de 8 mícrons sugere a existência de fibras micro e nano. Convertendo massa para numero de unidades, a lavagem individual de um artigo têxtil mostrou desprender entre milhares e centenas de milhares de fibras. Para uma extrapolação mundial, cerca de 40,4 mil toneladas de algodão e 21,5 mil toneladas de fibras sintéticas seriam liberadas em efluentes de esgoto. No Brasil estes valores corresponderiam, respectivamente, a 1,6 mil e 860 toneladas ano. Caso fossem tratadas em estações de tratamento de esgoto em condições ideais, seriam liberadas, em um ano, cerca de 737 toneladas de fibras sintéticas em escala mundial e 29 toneladas em escala nacional. Uma vez em cursos d\'água, estas fibras atingiriam, em ultima instância, o ambiente marinho, indicando a necessidade por soluções que combatam este tipo de poluição, sem antes deixar de explorar as lacunas do conhecimento, relacionadas, no âmbito têxtil, especialmente às diferenças metodológicas entre os estudos.
Since decades, the ubiquity of plastic materials in the environment has been a matter of discussion. Smaller pieces, named microplastic (< 5 millimeters) gained more attention recently and are now the focus of several studies. Textile fibers are a subgroup of microplastics and can be originated from several sources, including domestic washings, once filters and sewage treatment plants are not specifically designed to retain them. In the environment, these materials can reach concentrations up to millions of units per cubic meter, being available to many species. The objective of the present study was to evaluate washing parameters and also textile characteristics, which could influence in fibers emission from domestic washing machines. Experiments were done in ten successive times, with and without detergent, for four types of articles: cotton (as a pattern for comparison), acrylic, polyester and polyamide. Resulting effluents were then filtered in different porosities (< 1 millimeter, 500 microns, 63 microns, 8 microns), weighted, related to mass of textile articles and simulated regarding number of fibers. Results demonstrated that all textile articles emitted fibers during domestic washings. Ten successive washings represented a decrease in the emitted mass, as well as the use of detergent in relation to washings without the product. Differences between articles suggested variation of results according to textile characteristics, where the ranking of emission was: cotton, acrylic, polyamide and polyester. When considering the size of fibers, the majority was retained in the filter of the washing machine (porosity < 1 millimiter) and in 63 microns sieve, when compared to 500 microns sieve, showing the importance of the filter of the washing machine and the potential to decrease its porosity. Fibers retained in the filter- paper of 8 microns, couldnt be weighted because of its low mass, but their visualization suggests the existence of fibers in micro and nano scales. Converting mass to number of fibers, one individual washing was responsible for something between thousands and hundred of thousands of units. When extrapolating values to a global perspective, it reaches something around 40.4 thousand tonnes of cotton per year and 21.5 thousand tonnes of synthetic fibers per year. In a Brazilian perspective, these values correspond, respectively, to 1.6 thousand tonnes year and 860 tonnes year. If this effluents were all treated in sewage treatment plants, in ideal conditions, still they would release something like 737 tonnes of synthetic fibers per year in a global scale and 29 tonnes of synthetic fibers per year in a national scale. Once in water bodies, those fibers would reach the marine environment, indicating the necessity of solutions that could impair this kind of pollution, not before solving knowledge gaps, specially related, in the textile area, to methodology differences between studies

Les contaminants organiques d'intérêt émergent, tels que les phtalates (PAEs), les esters organophosphorés (OPEs), les bisphénols (BPs), les composés perfluorés (PFCs) et les microplastiques (MPs) sont aujourd'hui largement diffusés dans les milieux aquatiques. Leur présence dans la baie de Marseille, le Rhône et l'Atlantique Nord tropical est examinée dans cette étude. Il est démontré que le Rhône est une source d'apports de MPs et d'additifs plastiques dans le Golfe du Lion (Méditerranée NO) et que les intrusions de ses eaux sont suffisantes pour atteindre des concentrations de PFCs dépassant la norme annuelle moyenne de qualité environnementale dans la baie de Marseille. A Marseille, le zooplancton présent des concentrations de PAEs particulièrement élevées, ce qui soulève des questions sur les conséquences pour le réseau alimentaire marin et les ressources locales. Enfin, la possibilité d'un transport d’OPEs à longue distance est examinée à l'échelle de l'Atlantique Nord tropical
Organic contaminants of emerging concern, such as phthalates (PAEs), organophosphate esters (OPEs), bisphenols (BPs), perfluorinated compounds (PFCs) and microplastics (MPs) are nowadays widely distributed in aquatic environments. Their occurrence in the Bay of Marseille, the Rhône River and the tropical North Atlantic was investigated in this study. The Rhône River is shown to be a source of MP and plastic additive inputs to the Gulf of Lions (NW Mediterranean Sea) and intrusions of its waters are shown to be enough to attain PFC concentrations exceeding the annual average Environmental Quality Standard in the Bay of Marseille. In the Bay of Marseille, zooplankton samples exhibit particularly high PAE concentrations, raising questions concerning the consequences for the marine food web and local marine resources. Finally, the possibility of long-range OPE transport is examined at the scale of the tropical North Atlantic

Os plásticos têm trazido grandes benefícios aos humanos, sendo utilizados em diversas atividades como em aplicações médicas, entretenimento e na indústria de alimento. O uso crescente de plástico e seu descarte não adequado têm contribuído para o acúmulo deste detrito no meio ambiente, em especial nos oceanos onde tendem a acumular. Dentre os detritos de plástico de maior importância atualmente estão os microplásticos, que são partículas de plástico de tamanho entre 1 μm e 5 mm. Os principais riscos que os microplásticos oferecem são sua grande capacidade de persistência e dispersão no ambiente marinho, sua grande afinidade por poluentes persistentes orgânicos, sua a ingestão pela biota e a transferência para a teia trófica marinha. Dentre os ambientes marinhos mais impactados por microplásticos, estão as praias arenosas, onde estas partículas tendem a acumular após encalharem ao serem trazidas pelo mar. Este estudo teve como objetivo avaliar a contaminação por microplásticos em uma praia de uma área de proteção marinha costeira e avaliar a toxicidade de pellets virgens e coletados nesta praia no desenvolvimento embriolarval de mexilhão marrom Perna perna. Foram realizadas coletas de microplásticos entre o período de fevereiro de 2014 a fevereiro de 2015 na praia de Paranapuã em duas regiões do perfil da praia (linha de maré alta e supralitoral). As partículas foram analisadas individualmente em laboratório e quanto a composição de seu polímero por Espectrofotômetro de Infravermelho por Transformada de Fourier (FT-IR). Os resultados sugerem que a poluição por microplásticos na praia de Paranapuã ocorre ao longo do ano inteiro, porém variando em concentração ao longo do tempo e com um padrão de distribuição espacial irregular na praia. A concentração de microplásticos está aparentemente relacionada com a direção do vento, tendendo a ser maior quando a direção do vento é a favor da praia. A concentração de microplásticos na praia de Paranapuã (4,72 microplásticos/m²) é próxima àquela encontrada em outras praias no mundo e da região. Os experimentos de toxicidade demonstraram que tanto pellets de plástico virgens como aqueles coletados na praia inibem o desenvolvimento embriolarval de mexilhão marrom. Entretanto, os pellets coletados na praia mostraram uma alta toxicidade que resultou numa porcentagem de larvas anormais ou mortas de 100%, significativamente superior aos pellets virgens que foi de 23,5%. Acredita-se que a diferença de toxicidade entre os pellets virgens e coletados na praia pode ser causada por contaminantes adsorvidos na superfície dos pellets coletados no campo. Os resultados deste estudo sugerem que praias de áreas de proteção marinha costeira próximas a zonas urbanas e regiões portuárias apresentam risco de contaminação por plásticos. Apesar de terem acesso restrito a humanos, os microplásticos entram nestas praias através do ambiente marinho, podendo causar efeitos adversos na fauna destes ambientes. As informações deste trabalho contribuem para a melhor compreensão dos efeitos da contaminação de ambientes costeiros por microplásticos, fornecendo informações básicas para o desenvolvimento de políticas públicas voltadas para uma gestão deste tipo de poluição em áreas de proteção ambiental.
Plastics have great benefits to humans, used in various activities such as medical applications, entertainment and food industry. The increasing use of plastic and your inappropriate disposal have contributed to the accumulation of this debris in the environment, particularly in the oceans where they tend to accumulate. Among the most important plastic waste are the microplastic which are plastic particles of size between 1 μm and 5 mm. The main risks that microplastics offer are your large capacity persistence and dispersal in the marine environment, your great affinity for persistent organic pollutants and their ingestion by biota and transfer to the marine food web. Among the marine environments most impacted by microplastics are sandy beaches where these particles tend to accumulate after carried by sea. This study evaluate the contamination by microplastics on a beach of a coastal marine protected area, and assess the virgin pellets toxicity and collected on this beach in embryo-larval development of brown mussel Perna perna. Microplastics samples were collected in the period from February 2014 to February 2015 on the beach of Paranapuã in two regions of the beach (high tide line and supralittoral). The particles were analyzed individually in the laboratory and the composition of your polymer was identified for Fourier Transform infrared spectroscopy (FT-IR). The results suggest that pollution microplastics in Paranapuã beach is continuous in entire year, but varying in concentration over time and with a pattern irregular of spatial distribution on the beach. The microplastics concentration is apparently related to the wind direction, tends to be higher when the wind direction is downwind. The concentration of microplastics on the beach Paranapuã (4.72 microplastics/m²) is similar to other beaches in the world. The toxicity experiments showed that both virgin plastic pellets as those collected on the beach inhibit embryo-larval development of brown mussels. However, the pellets collected at the beach showed high toxicity resulting in abnormal or percentage of dead larvae 100%, significantly higher than for virgin pellets, which was 23.5%. It is believed that the difference in toxicity between the virgin pellets and collected on the beach can be caused by high concentration of adsorbed contaminants on the surface of the pellets collected in the field. The results of this study suggest that beaches areas of coastal marine protection near urban areas and port areas have high risk of contamination by plastics. Although this beach has access restricted to humans, microplastics enter these beaches through the marine environment, potentially causing adverse effects on the local fauna of these environments due to your high toxicity. The information from this study contribute to a better understanding of the effects of contamination of coastal environments by microplastics, providing basic information for the development of public policies for management of this type of pollution in the areas of environmental protection.

A matéria prima das indústrias transformadoras de utensílios plásticos são os pellets de plástico, que recebem quantidades significativas de aditivos os quais possuem metais pesados e elementos tóxicos. Devido à perda desses pellets durante os processos de produção e transporte, tais contaminantes são liberados no ambiente. Este estudo investiga as interações entre os metais dissolvidos em pellets coletados em diferentes praias do litoral de São Paulo. Especificamente, o estudo comparou a realização do método em grânulos virgens, ou seja, aqueles obtidos a partir de uma fábrica de moldagem com os recolhidos das praias. Foram quantificados os elementos: Al, Cr, Cu, Fe, Mn, Sn, Ti e Zn empregando a técnica de espectrometria de emissão atômica com plasma indutivamente acoplado (ICP-OES). Os polímeros foram solubilizados via digestão ácida (EPA3050B). As concentrações dos metais exibiram um elevado grau de variabilidade, sendo Al e Fe os elementos de maiores concentrações 58,63 mg kg-1, praia de Tabatinga e 391,56 mg kg-1, praia de Itaguaré, respectivamente. Diferenças de afinidades entre os metais para os pellets coletados no ambiente e aqueles obtidos diretamente a partir de uma processadora de plásticos (virgem) também foram identificados. A adsorção de metais em pellets coletados é maior em relação aos pellets virgens, isso ocorre devido ao desenvolvimento de sítios de adsorção na superfície para realização de foto-oxidação, incrustação e deposição de sedimentos finos e/ou partículas durante a exposição a condições ambientais. Este estudo demonstrou que pellets de plástico têm o potencial acumular e transportar metais no ambiente marinho, mesmo em pequena quantidade. Eles podem ser considerados como um vetor para o transporte de metais no meio ambiente, e podem ter o potencial de acumular metais em organismos após a ingestão.
The raw material of plastic industries is plastic pellets, which receive significant amounts of additives which contain heavy metals and toxic elements. Due to the loss of these pellets during the processes of production and transportation, such contaminants are released into the environment. This study investigates the interactions between metals dissolved in pellets collected in different beaches of the coast of São Paulo state. Specifically, the study compared the performance of the method in virgin granules, ie, those obtained from a molding factory with those collected from the beaches. The following elements quantified: Al , Cr , Cu , Fe , Mn , Sn , Ti and Zn in samples of virgin pellets supplied by Braskem, manufacturer of resins, employing the technique of Inductively coupled plasma atomic emission spectroscopy ( ICP - OES .) The polymers were solubilized via acid digestion (EPA3050B). The metal concentrations exhibited a high degree of variability being Al and Fe elements with higher concentrations: 58.63 mg kg-1 at Tabatinga beach and Fe 391.56 mg kg-1, at Itaguaré beach. Affinity differences between metals for pellets collected in the environment and those obtained directly from a processor of plastics (virgin) were also identified. The maximum adsorption for virgin pellets ranged between 14.09 mg kg-1 (polyethylene, used as control) to 58.63 mg kg-1 for Al. However, for the other elements except Fe, the concentrations were below the limit of quantification. The metal adsorption on pellets collected is greater compared to virgin pellets. This is due to the development of viable local surface for performing photo-oxidation, scaling and deposition of fine sediments and/or particles during exposure to environmental conditions. This study demonstrated for the first time, that the plastic pellets have the potential to accumulate metals and transporting the marine environment, even in small quantities. They can be considered as a vector for the transport of metals in the environment and may have the potential to accumulate metal to organisms bodies after ingestion.

Depuis 70 ans, les débris plastiques dont la fin de vie a été négligée par les sociétés humaines s’accumulent dans les océans. L’évaluation des effets engendrés par cette contamination ubiquitaire est une préoccupation majeure, notamment au regard des micro- et potentiels nanoplastiques (MNP ; < 5 mm) du fait de leur biodisponibilité pour la plupart des organismes marins. L’objectif de cette thèse était de déterminer les effets des MNP sur les jeunes stades de vie d’une espèce ingénieure des habitats côtiers, l’huître creuse Crassostrea gigas. Les impacts des MNP sur ces jeunes stades sont apparus dépendants de la taille des particules. Le rapport surface/volume important des nanosphères de polystyrène (nano-PS ; 50 nm) a favorisé les interactions avec les gamètes et embryons, induisant une inhibition de la fécondation et de l’embryogénèse tandis que les microsphères (0,5 et 2 μm) n’ont causé aucun effet phénotypique visible. La toxicité des nano-PS est apparue dépendante de leurs propriétés de surface (e.g groupements chimiques, charge) qui dirigent leur agrégation dans l’eau de mer et les interactions avec les membranes biologiques. Les nano-PS cationiques, qui restent à l’échelle nanométrique dans l’eau de mer, sont à l’origine des effets toxiques les plus marqués. L’exposition embryonnaire à une dose non létale a notamment diminué les performances larvaires et modulé la réponse de la génération suivante à une réexposition embryonnaire. Toutefois, ces effets néfastes sont observés à des concentrations numéraires supposément non-représentatives de l’environnement actuel (la quantité de NP n’étant pas caractérisée en mer à ce jour), suggérant un risque limité des micro- et nanosphères de polystyrène sur les jeunes stades de C.gigas. Les prochaines études devront tenir compte de la complexité et de la réalité des MNP environnementaux (e.g. polymères, formes, contaminants adsorbés, concentrations) sur plusieurs générations de bivalves dans le but d’appréhender plus précisément le risque pour les écosystèmes côtiers
For 70 years, mismanaged plastic waste accumulates in the oceans. Risk assessment of this contamination is a major concern, especially regarding micro- and presumably nanoplastics (MNP; <5 mm) which are bioavailable for most marine species. The objective of this thesis was to assess adverse effects of MNP to early life stages of the oyster Crassostrea gigas, a key engineer species in coastal ecosystems. MNP toxicity on oyster young stages depended on the particle size. The high surface area- to - volume ratio of polystyrene nanobeads (nano- PS; 50 nm) promoted their reactivity and interactions with biological membranes of gametes and embryos, leading to an inhibition of the fertilization and embryogenesis success while 0.5 and 2 μm polystyrene beads had any detectable effects. The nano-PS toxicity depended on the particle surface properties (e.g. surface functionalization and charge) which govern their aggregation in seawater and affinity with biological membranes. Furthermore, cationic nano- PS which remained at nanometric scale in seawater, had the highest toxic potential to oyster gametes and embryos. Embryonic exposure to these particles at a non-lethal dose reduced first generation larval performances and modulated larval growth at the second generation in response to the same embryonic exposure. All adverse effects were observed at supposedly unrealistic environmental concentrations (no in situ data exists on NP), suggesting low risk of polystyrene beads to oyster early life stages. Future studies will have to take into account the complexity and reality of MNP in oceans (e.g. polymer and shape diversity, concentrations, contaminants adsorption) to assess effects on bivalve species across generations in order to establish more accurately the risks for coastal environments

La présence et les effets de micro- (<5 mm) et nanomatériaux (<100 nm, NM) dans l’environnement est un sujet d’actualité. Les écosystèmes aquatiques sous forte pression de pollution présentent des mélanges de produits chimiques, dans lesquels les micro- et NMs, en raison de leur rapport surface/volume élevé et de leur surface hydrophobe, peuvent agir comme des éponges pour les polluants. Ce phénomène peut modifier la biodisponibilité de ces derniers et, ainsi, moduler leur toxicité pour les organismes aquatiques. Cette thèse avait donc comme objectifs : (1) d’évaluer la biodisponibilité et la toxicité potentielles de nanoplastiques (NP) et de microplastiques (MP) de polystyrène seuls, et de MP avec des hydrocarbures aromatiques polycycliques (HAP) ad/absorbés pour la larve d’artémie et le poisson zèbre; (2) de déterminer la capacité de sorption des HAP par des MP et NM d’oxyde de graphène (GO); (3) d’évaluer la biodisponibilité et la toxicité potentielles des NM GO seuls et avec des HAP ad/absorbés chez le poisson zèbre.L’exposition à des MP seuls n’a pas eu d’impact significatif sur la survie pour la larve d’artémie et le poisson zèbre, alors que des concentrations élevées (mg/L) de MP avec du benzo(a)pyrène (B(a)P) ad/absorbé et du B(a)P seul ont entraîné une toxicité aiguë. Les MP se sont révélés des vecteurs de B(a)P chez les organismes en développement. Les résultats ont montré que les MP (0,5 µm) de petite taille présentaient une capacité de sorption du B(a)P plus élevée que les MP de plus grande taille (4,5 µm). Dans le cas d'un mélange complexe de HAP, comme celui obtenu à partir de la solubilisation d'un pétrole brut (WAF), une sorption limitée pour les MP de 4,5 µm, due à l'hydrophobie et à la concentration initiale des HAP, a été observée. Chez le poisson adulte, les HAP n’ont pas été transportés par les MP après une exposition de 21 jours. Seuls les poissons exposés aux MP pendant 21 jours ont présenté des changements au niveau de la transcription du gène cyp1a lié au métabolisme de biotransformation dans le foie, ainsi qu'une augmentation significative de la prévalence de la vacuolisation du foie. 21 jours d'exposition aux NP, mais pas aux MP, ont provoqué un stress oxydatif chez les poissons adultes. L'ingestion de NP a été observée chez les organismes en développement. Chez les embryons, les NP ont été internalisés dans les yeux, le sac vitellin et la queue.GO a montré une plus grande capacité de sorption pour B(a)P que le MP. Pour le mélange de HAP du WAF, la sorption vers le GO était également supérieure à celle des MP. Chez les embryons exposés, le taux de malformation a augmenté de manière significative chez les embryons exposés aux concentrations les plus élevées (5 ou 10 mg/l) de GO, de GO réduit seul et avec du B(a)P ad/absorbé. Selon l'analyse chimique dans les tissues de poisson adulte, la biodisponibilité des HAP avec de GO pour les poissons était plus faible que dans le cas des HAP seuls. Seules les réponses biochimiques et les gènes liés au métabolisme de biotransformation ont été altérés dans le foie des poissons exposés au B(a)P pendant 3 jours. Au contraire, les branchies des poissons exposés au GO avec du B(a)P ad/absorbé et au B(a)P pendant 3 jours et co-exposés au GO et au WAF pendant 21 jours ont montré un stress oxydatif significativement plus élevé que les poissons témoins. Un effet neurotoxique commun a été provoqué chez tous les poissons traités pendant 21 jours. Enfin, les poissons adultes exposés au GO ont présenté une ingestion de GO et une vacuolisation du foie. Le présent travail démontre la capacité des MP avec des HAP ad/absorbés à provoquer des effets sublétaux (1) et à porter des HAP (2) chez l’artémie et le poissons zèbre. Enfin, le GO était plus porteur de HAP pour le poisson zèbre que le MP (3) en raison de sa plus grande capacité de sorption (2), exerçant un stress oxydatif et une neurotoxicité comme principaux effets sublétaux chez le poisson zèbre adulte
Presence and effects of micro- (< 5mm) and nanomaterials (<100 nm, NM) in the environment are a current issue of concern. Aquatic ecosystems with high pollution pressure already present a cocktail of chemicals, where micro- and NMs can act as sponges for these pollutants due to their high surface to volume ratio and hydrophobic surface. This phenomenon can alter the bioavailability of the pollutants present in the aquatic ecosystem, especially for hydrophobic compounds and, therefore, modulate their toxicity to aquatic organisms. Therefore, in the present Thesis the following objectives were established: (1) To assess the potential bioavailability and toxicity of polystyrene nanoplastics (NPs), and of microplastics (MPs) alone and with sorbed polycyclic aromatic hydrocarbons (PAHs) to brine shrimp larvae and zebrafish; (2) To determine sorption capacity of PAHs to MPs and graphene oxide NMs (GNMs); (3) To assess the potential bioavailability and toxicity of GNMs alone and with sorbed PAHs to zebrafish.Exposure to pristine MPs did not cause any significant impact on brine shrimp larvae and zebrafish embryo survival, while some treatments containing elevated concentrations (mg/L) of MPs with sorbed benzo(a)pyrene (B(a)P) and B(a)P alone resulted in acute toxicity. In addition, both sizes of MPs were successful vectors of B(a)P to brine shrimp and zebrafish embryos. Results indicated that small MPs (0.5 µm) showed higher maximum sorption capacity for B(a)P than larger MPs (4.5 µm). In the case of a complex and environmentally relevant PAH mixture, as that formed in the water accommodated fraction (WAF) of a crude oil, a relatively limited sorption to 4.5 µm MPs, driven by the hydrophobicity and initial concentration of each PAH, was observed. In adult zebrafish, MPs did not act as PAH vehicle after 21-day exposure to MPs with sorbed PAHs. Only fish exposed to MPs for 21 days presented changes in the transcription level of biotransformation metabolism-related gene cyp1a in the liver, along with a significant increase in the prevalence of liver vacuolisation. 21 days of exposure to NPs, but not to MPs, caused oxidative stress in adult zebrafish. Ingestion of NPs was observed in the developing organisms (brine shrimp and zebrafish). In embryos, fluorescent NPs were specially localised in the eyes, yolk sac and tail, showing their capacity to translocate and spread into the embryo body.For GNMs, graphene oxide (GO) showed a higher sorption capacity for B(a)P than MPs. For the PAH mixture of the WAF, sorption to GO was also higher than to MPs. In embryos exposed to different GNMs alone and with PAHs, no significant mortality was recorded for any treatment. Nevertheless, malformation rate increased significantly in embryos exposed to the highest concentrations (5 or 10 mg/L) of GO, reduced GO alone and with sorbed B(a)P. According to chemical analysis of adult fish tissues, bioavailability of PAH sorbed to GO for fish was lower than in the case of PAHs alone. Only biochemical responses and genes related to biotransformation metabolism were altered in the liver of fish exposed to B(a)P for 3 days. Transcription level of genes related to oxidative stress were not altered. On the contrary, the gills of fish exposed to GO with sorbed B(a)P and to B(a)P for 3 days and co-exposed to GO and WAF for 21 days showed significantly higher oxidative stress than control fish. A common neurotoxic effect was caused in all fish treated for 21 days. Finally, adult fish exposed to GO presented GO ingestion and liver vacuolisation, but absence of GO translocation to the adult tissue was reported. The present work shows evidences of the capacity of MPs with sorbed PAHs to cause sublethal effects (1) and to carry PAHs (2) in brine shrimp and zebrafish. Finally, GO was greater carrier of PAHs to zebrafish than MPs (3) due to its higher sorption capacity (2), exerting oxidative stress and neurotoxicity as the main sublethal effects in adult zebrafish
La presencia y los efectos de micro- (<5 mm) y nanomateriales (100 nm, NM) en el medio ambiente es un tema de preocupación actual. En sistemas acuáticos que presentan un coctel de químicos debido a la alta presión de la contaminación, los micro- y NMs pueden actuar como esponjas para los contaminantes debido a su alto ratio superficie/volumen y a la hidrofobicidad de su superficie. Este fenómeno puede alterar la biodisponibilidad de los contaminantes presentes en los ecosistemas acuáticos, especialmente para los compuestos hidrófobos, y seguidamente, modular su toxicidad para los organismos acuáticos. Por ello, en la presente tesis los siguientes objetivos fueron establecidos: (1) Evaluar la biodisponibilidad y la toxicidad potencial de nanoplásticos de poliestireno (NPs), y de microplásticos (MPs) solos o con hidrocarburos aromáticos policíclicos ad/absorbidos (HAPs) para la larva de Artemia y el pez cebra; (2) Determinar la capacidad de ad/absorción de HAPs por los MPs y los NMs de óxido de grafeno (GNMs); (3) Evaluar la biodisponibilidad y toxicidad de GNMs solos o con HAPs ad/absorbidos para el pez cebra.La exposición a MPs prístinos no causó ningún impacto significativo en la supervivencia de la larva de Artemia o del embrión de pez cebra, mientras que algunos tratamientos que contenían elevadas concentraciones (mg/L) de MPs con benzo(a)pireno (B(a)P) ad/absorbido y B(a)P sólo resultaron en toxicidad aguda. Además, ambos tamaños de MPs fueron exitosos vectores de B(a)P en larvas de Artemia y embriones de pez cebra. Los resultados indicaron que los MPs pequeños (0.5 μm) mostraron una mayor capacidad máxima de ad/absorción de B(a)P que los MPs grandes (4.5 μm MPs). Para una mezcla compleja y medioambientalmente relevante de HAPs, como es la formada en la fracción acomodada al agua (WAF) de un petróleo crudo, se observó una ad/absorción limitada relativamente a 4.5 μm MPs y que dependió de la hidrofobicidad y la concentración inicial de cada HAP. En adultos de pez cebra, los MPs no actuaron como vehículos de HAP después de 21 días de exposición a MPs con HAPs ad/absorbidos. Solo aquellos peces expuestos a MPs durante 21 días presentaron cambios en los niveles de transcripción del gen cyp1a relacionado con el metabolismo de biotransformación en el hígado, junto con un aumento significativo de la prevalencia de la vacuolización del hígado. 21 días de exposición a NPs, pero no a MPs, causó un estrés oxidativo en los adultos de pez cebra. La ingestión de NPs se observó en los organismos en desarrollo (Artemia y pez cebra). En embriones, los NPs fluorescentes se localizaron específicamente en los ojos, saco vitelino y cola, mostrando la capacidad de los mismos para ser internalizados y repartidos en el interior del cuerpo del embrión.Para los GNMs, el óxido de grafeno (GO) presentó una mayor capacidad de ad/absorción de B(a)P que los MPs. Para la mezcla de HAPs del WAF, la ad/absorcíon a GO fue de nuevo mayor que para los MPs. Para los embriones expuestos a diferentes GNMs solos y con HAPs no se obtuvo una mortalidad significativa. Aun así, el ratio de malformaciones aumento significativamente en embriones expuestos a las concentraciones más altas (5 o 10 mg/L) de GO, GO reducido solo o con B(a)P ad/absorbido. De acuerdo con los ensayos químicos en el tejido de pez adulto, la biodisponibilidad de HAP ad/absorbidos a GO para peces fue menor que en los peces expuestos a HAPs solos. Solo se vieron alteradas las respuestas bioquímicas y los genes relacionados con el metabolismo de biotransformación en hígado de pez expuesto a B(a)P durante 3 días. [...]

Au cours des dernières années, les plastiques ont attiré un intérêt particulier du public et des scientifiques. Les plastiques ont été classés parmi les polluants émergents, notamment dans le milieu marin de par leur présence ainsi que leur persistance, en particulier les microplastiques (< 5mm, MPs). De nombreuses études ont reportées la présence de MPs dans le milieu marin (eau de surface et sédiments). Cependant, il n’existe pas de méthodes standards pour évaluer leurs potentielle toxicités ainsi que leur rôle en tant que vecteur de polluants au sein des organismes. Cette thèse avait pour objectif, (1) l’étude de la sorption de composés chimiques modèles sur des MPs, (2) l’étude de la toxicité de ces composés adsorbés artificiellement sur le poisson zèbre (Danio rerio) ainsi que (3) la caractérisation et l’étude de MPs environnementaux. La première partie de cette thèse avait pour but d’étudier les processus de sorption de trois composés modèles ; l’acide perfluorooctanesulfonique (PFOS), benzo[a]pyrene (BaP) et l’oxybenzone (BP3) ; sur différentes tailles et différents polymères industriels. La seconde partie concernait l’étude de la vectorisation de ces 3 composés modèles adsorbés sur MPs en utilisant les stades précoces, juvéniles et adultes de poisson zèbre, au travers d’exposition directe ou via exposition trophique. La dernière partie évaluait la toxicité de MPs environnementaux provenant de deux plages (Guadeloupe, France), en utilisant les mêmes procédures que pour l’évaluation de la toxicité de MPs artificiels. La caractérisation polymérique et chimique des échantillons environnementaux a également été étudiée. L’étude de la sorption des polluants démontra des différences de réponses (cinétiques et efficacité de la sorption) dépendant de la taille des particules ainsi que des propriétés chimiques des composés. La toxicité des MPs artificiellement dopés avec des composés modèles a d’abord été évaluée selon la ligne directrice de l’OCDE 236 ainsi que via une exposition trophique chronique, débutant à l’état larvaire jusqu’à des poissons âgés de 5 mois. Des biomarqueurs à l’échelle individuelle et moléculaire ont été suivis au cours de l’exposition. Les résultats principaux correspondaient à une faible toxicité aiguë sur les stades précoces de développement (embryons et larves) exposés aux particules, aux extraits organiques mais également aux lixiviats, de MPs artificiels ou environnementaux. Néanmoins, l’ingestion des MPs au cours de l’exposition trophique a conduit à des effets à long-terme, avec des intensités différentes liées aux composés chimiques adsorbés aux MPs. Les effets toxiques incluaient des altérations de la croissance (taille et poids des poissons), des effets sur la reproduction, des modifications comportementales des adultes exposés ainsi que des changement d’activité natatoire des larves de la génération F1. En conclusion, cette thèse a permis de mettre en évidence le fait que (1) les MPs ont la capacité d’être des vecteurs de polluants mais qu’ils peuvent également (2) induire des effets sublétaux sur des juveniles et adultes de poisson exposés aux MPs via la nourriture mais également sur la progéniture F1
During the last decades, plastics have gained interest from media, public and scientists. Plastics have been categorized as emerging pollutants particularly in the marine environment due to their ubiquity and persistence, particularly microplastics (< 5 mm, MPs). Numerous studies reported the occurrence of MPs in the marine environment (surface water, sediments). However, neither there exist standardized nor harmonized methods to evaluate their potential toxicity and their role as vector of hazardous chemicals into organism. This thesis had three main objectives, (1) the investigation of sorption of chemicals models on MPs, (2) the study of the toxic potential of these sorbed chemicals on zebrafish and (3) the characterization and the study of the toxicity of environmental MPs. The first part of the thesis aimed at the investigation of the sorption processes of three model pollutants - perfluorooctanesulfonic acid (PFOS), benzo[a]pyrene (BaP) and oxybenzone (BP3) - on pristine MPs using different sizes and polymer types. The second part studied the vectorization of the three compounds sorbed on MPs toward zebrafish (Danio rerio) embryos, juveniles and adults through direct or trophic exposures, and their toxicities. The third part investigated the toxicity of environmental samples of MPs from two sandy beaches (Guadeloupe Island, France), using the same procedure as above, as well as the characterization of additives and adsorbed chemicals through a non-target approach. Study of pollutants sorption demonstrated differences in pattern (e.g. kinetics, sorption efficiency), depending on size particles and chemical used. Potential adverse effects of MPs associated with chemicals were investigated in zebrafish embryos using OECD 236 guideline and by using a chronic exposure from larvae or juveniles up to 5-months old adults through trophic exposure. Molecular and individual toxicological endpoints were monitored during exposure. Main findings were the low acute toxicity of MPs on early life stages (embryos and larvae) exposed to particles, organic extracts or leachates. Nevertheless, the ingestion of MPs by juveniles and adults led to a significant long-term toxicity for all tested MPs albeit with different intensity according to the spiked chemicals and to the environmental samples. Deleterious effects included growth alteration, reprotoxicity, behavioral disturbances as well as hyperactivity observed in offspring of exposed fish. In conclusion, the present work revealed that (1) MPs may play a role in the vectorization of pollutants and (2) may induce significant sublethal effects in juveniles of zebrafish chronically fed with pristine MPs or MPs artificially spiked with pollutants. Same conclusions were observed (3) with environmental MPs

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

Microplastics can be defined as “any synthetic solid particle or polymeric matrix, with regular or irregular shape and with size ranging from 1 μm to 5 mm, of either primary or secondary manufacturing origin, which are insoluble in water”. The growing demand and consequent production of plastic products both at microscale (e.g., personal care products) and at macroscale with inappropriate disposal subsequent degradation in the environment has turned microplastics into global emergent pollutants of the aquatic environment. In fact, the levels of microplastics that have been found in river and lake sediments, raise concern about ingestion and potential negatives effects of microplastics in aquatic benthic invertebrates, particularly those who feed on particulate matter. Possible effects at different levels of biological organisation (sub -organismal up to community level s) are still overlooked , as well as the study of the toxic effects of microplastics to invertebrate biota under relevant exposure scenarios, especially considering climatic change. Therefore, the objective of this thesis was to evaluate the effects of irregularly shaped pol y ethylene microplastics (one of the polymer type microplastics most produced and found in aquatic sediments) using a holistic approach that combines sub -organismal, organismal, population and community level responses, aiming to produce relevant ecotoxicol o gical data for risk assessment of microplastics in freshwaters. First, a quantitative and qualitative assessment of the ingestion of microplastics was evaluated in two model aquatic species, the dipteran Chironomus riparius and the endobenthic oligochaet e Lumbriculus variegatus, as these species feed on particulate matter, being prone to ingest microplastics. Along with the assessment of the ingestion of microplastics, the effects (both at sub -cellular and organismal level) were assessed in an attempt to link ingestion and potential deleterious effects induced by the particles per se. Activation of immune response (phenoloxidase activity), oxidative stress and damage , as well as , effects on life -history traits (larval growth and development) , were observed in C. ripariu s and associated to the augmented ingestion and retention of microplastics in their gut when compared to L. variegatus, which only presented slight evidence of oxidative stress and no effects on reproduction. The combined exposure of microplastics with natural stressors was then performed in Chironomus riparius (the most sensitive species ). Temperature, salinity and food shortage were used as natural stressors relevant under climate change scenarios and that could modulate the ingestion and induced effects of microplastics in relevant exposure scenario s . The results show that interactions between microplastics exposure and these natural stressors are complex and mainly additive and antagonistic effects were observed. However, results also identified conditions (low temperatures and severe food shortage) where sub - lethal effects of MPs to natural populations of C. riparius can be stronger than predicted by standard toxicity assays. These combined exposures revealed that under different environmental conditions, toxicity of MPs is not simply a reflection of internal concentrations of particles. Conceivably the main research gap that subsists is the investigation on the ecological effects of microplastics. For that purpose, this thesis performed a mesocosms approach addressing the effects at the community structure and ecosystem functioning, vital to deliver higher - tier risk assessments . This higher -tier approach (i.e., using artificial streams inoculated with natural benthic invertebrate communities) showed that the exposure to a pool of different -sized polyethylene microplastics affected the macroinvertebrate community structure, mainly by reducing the abundance of deposit -feeders and grazers. The ingestion of microplastics by different invertebrate feeding groups correlated positively with the effects as deposit -feeders and grazers presented the higher number of microplastics inside the organisms’ guts. A slight reduction in primary production was observed and may be a possible direct effect of microplastics on periphyton growth. Only slight effects were observed in terms of leaf litter decomposition signalling that the exposure to polyethylene microplastics might not have affected feeding behaviour of shredders or in turn that exposure period was too short to reveal trait -mediated indirect effects . In conclusion, the present thesis demonstrates that microplastics can be ingested by some aquatic macroinvertebrates and that enhanced ingestion can potentially pose a risk to natural invertebrates’ population. Despite considerable interspecific variation in sensitivity to polyethylene microplastics, their presence in sediments can alter community structure and represent a risk to ecosystem functioning at the long -term. The present thesis confirms that immune responses and oxidative stress as key molecular initiating event s in microplastic toxicity, shows that assessing the internal concentrations of plastic particles is critical for a correct evaluation of effects in biota and highlights the need to incorporate more invertebrate species and relevant exposure conditions for an accurate risk assessment of microplastics in freshwaters.
Os microplásticos podem ser definidos como “qualquer partícula sólida de origem sintética ou matriz polimérica, de forma regular ou irregular e com tamanho entre 1 μm to 5 mm, tanto de origem de produção primária como secundária e que são insolúveis em água”. A crescente procura por este tipo de produtos e consequentemente a sua maior produção, tanto à microescala (p. ex.: produtos de higiene pessoal), como à macroescala com descarte incorreto e consequente degradação no meio ambiente, tornaram os microplásticos num poluente emergente do ambiente aquático à escala global. Assim sendo, os níveis de microplásticos que têm vindo a ser encontrados nos sedimentos de rios e lagos geram preocupação acrescida relativamente à sua potencial ingestão e efeitos gerados por esta em invertebrados bentónicos, particularmente aqueles que se alimentam de matéria orgânica particulada. Existe ainda pouca informação relativamente aos possíveis efeitos provocados pelos microplásticos nos diversos níveis de organização biológica (desde o nível suborganismal até à comunidade), bem como, em relação aos efeitos dos microplásticos em invertebrados sob cenários relevantes de exposição, em especial considerando as alterações climáticas. Assim, o principal objetivo desta tese foi o de avaliar os efeitos de microplásticos com forma irregular de polietileno (um dos polímeros mais produzidos no mundo e também dos mais encontrados nos sedimentos de rios e lagos), usando uma abordagem holística que combina respostas ao nível sub-organismal, organismal, populacional e da comunidade, pretendendo deste modo facultar informação ecotoxicológica relevante que possa ser usada na avaliação de risco dos microplásticos em ambientes dulçaquícolas. Para tal, a ingestão de microplásticos foi avaliada em termos quantitavos e qualitativos em duas espécies bentónicas -modelo, o díptero Chironomus riparius e o oligoqueta Lumbriculus variegatus, que sendo espécies que se alimentam de matéria particulada, estarão mais suscetíveis à ingestão de microplásticos. Paralelamente à avaliação da ingestão de microplásticos, foram também avaliados os efeitos (tanto a nível sub-celular como ao nível do organismo) numa perspetiva de relacionar ingestão e efeitos. Os principais efeitos observados prenderam-se assim com a ativação da resposta imune (medida através da atividade da fenoloxidase), stress e dano oxidativo, bem como efeitos ao nível do ciclo de vida em C. riparius (diminuição do crescimento larvar e atraso no desenvolvimento). Estes efeitos foram assim relacionados com a maior ingestão de microplásticos, quando comparada com a ingestão observada em L. variegatus, que somente apresentou sinais ligeiros de stress oxidativo e ausência de efeitos na reprodução. A espécie mais sensível, Chironomus riparius, foi então exposta a microplásticos em combinação com diversos stressores naturais. Os stressores naturais escolhidos foram a temperatura, salinidade e limitação da disponibilidade de alimento, sendo estes relevantes em cenários de alterações climáticas, e capazes de alterar a ingestão e consequentemente os efeitos provocados pelos microplásticos. Os resultados demonstram que as interações decorrentes da exposição conjunta de microplásticos com os stressores naturais são complexas, sendo que os efeitos observados foram maioritariamente aditivos ou antagonísticos. Contudo, sob determinadas condições como baixa temperatura e significativa limitação da disponibilidade de alimento, os efeitos sub -letais dos microplásticos nas populações naturais de C. riparius poderão ser mais severos que o previsto pelos ensaios ecotoxicológicos padronizados. Estes efeitos combinados revelaram ainda, que sob determinadas condições ambientais, os efeitos tóxicos dos microplásticos poderão não ser simplesmente um reflexo das concentrações de microplásticos encontrada s no interior dos organismos. A avaliação dos efeitos ecológicos da exposição a microplásticos é possivelmente , a principal lacuna que subsiste na investigação. Assim, esta tese procurou colmatar essa lacuna, com recurso a um ensaio usando rios artificiais (mesocosmos), em que foram estudados os efeitos na estrutura da comunidade de invertebrados bentónicos, bem como nas funções providenciadas pelo ecossistema, vitais para uma melhor avaliação de risco. Esta abordagem demonstrou que a exposição a microplásticos de polietileno de diversos tamanhos afetou a estrutura da comunidade, sobretudo através da redução da abundâ ncia de invertebrados coletores de depósito e raspadores. A ingestão de microplásticos pelos diferentes grupos funcionais de invertebrados correlacionou -se positivamente com os efeitos, uma vez que coletores de depósito e raspadores apresentaram o maior número de microplásticos no seu interior . Foi ainda observada uma ligeira redução na produção primária que poderá estar relacionada com um efeito direto dos microplásticos no crescimento do perifíton. De igual modo, observou -se apenas uma ligeira redução na decomposição da folhada, sendo este efeito indicativo de que a exposição a microplásticos de polietileno poderá não afetar significativamente o comportamento alimentar dos fragmentadores, ou em alternativa o tempo de exposição poderá ter sido demasiado curto para que estes efeitos indiretos se possam ter manifestado. Em conclusão, a presente tese demonstra que os microplásticos podem ser ingeridos pelos macroinvertebrados de água doce e representar um risco para as populações naturais. Apesar de se ter verificado uma considerável variação interespecífica na sensibilidade aos microplásticos de polietileno, a sua presença nos sedimentos pode alterar a estrutura das comunidades de macroinvertebrados bentónicos e alterar o funcionamento dos ecossistemas a longo prazo. A presente tese comprova também que a resposta imune e o stress oxidativo são eventos -chave de início a nível molecular na toxicidade dos microplásticos, e demonstra que a avaliação das concentrações internas dos microplásticos é crucial para uma correta avaliação dos efeitos nos organismos. Salienta -se ainda a necessidade da incorporação de mais espécies de invertebrados, assim como, de cenários relevantes de exposição para uma avaliação de risco mais precisa dos microplásticos nos ecossistemas dulçaquícolas.
Programa Doutoral em Biologia e Ecologia das Alterações Globais

abstract: Plastic pollution has become a global threat to ecosystems worldwide, with microplastics now representing contaminants reported to occur in ambient air, fresh water, seawater, soils, fauna and people. Over time, larger macro-plastics are subject to weathering and fragmentation, resulting in smaller particles, termed ‘microplastics’ (measuring < 5 mm in diameter), which have been found to pollute virtually every marine and terrestrial ecosystem on the planet. This thesis explored the transfer of plastic pollutants from consumer products into the built water environment and ultimately into global aquatic and terrestrial ecosystems. A literature review demonstrated that municipal sewage sludge produced by wastewater treatment plants around the world contains detectable quantities of microplastics. Application of sewage sludge on land was shown to represent a mechanism for transfer of microplastics from wastewater into terrestrial environments, with some countries reporting as high as 113 ± 57 microplastic particles per gram of dry sludge. To address the notable shortcoming of inconsistent reporting practices for microplastic pollution, this thesis introduced a novel, online calculator that converts the number of plastic particles into the unambiguous metric of mass, thereby making global studies on microplastic pollution directly comparable. This thesis concludes with an investigation of a previously unexplored and more personal source of plastic pollution, namely the disposal of single-use contact lenses and an assessment of the magnitude of this emerging source of environmental pollution. Using an online survey aimed at quantifying trends with the disposal of lenses in the US, it was discovered that 20 ± 0.8% of contact lens wearers flushed their used lenses down the drain, amounting to 44,000 ± 1,700 kg y-1 of lens dry mass discharged into US wastewater. From the results it is concluded that conventional and medical microplastics represent a significant global source of pollution and a long-term threat to ecosystems around the world. Recommendations are provided on how to limit the entry of medical microplastics into the built water environment to limit damage to ecosystems worldwide.
Dissertation/Thesis
Doctoral Dissertation Biology 2020

Since its invention, in the 1950s, plastic can be found in almost every object or structure. It has created numerous opportunities in many fields, boosting markedly mankind’s development and even its life span. However, combined with modern consumption patterns, in a world that is more and more urban and technological, plastic amounts have reached proportions never seen before. Consequently, plastic waste quantities are also exceeding all the limits reached so far and it is ending in our oceans for two main reasons: reckless behaviour of consumers and improper waste management. National waste management systems worldwide are facing severe challenges, especially at the moments of collection and disposal. That happens particularly in Asia and the causes are lack of money and structures, and governments and citizens lack of interest. Marine plastic pollution has been affecting all humanity for several decades but only recently it has been recognised. Each year, at least eight million tonnes of plastics leak into the oceans. Its sources are numerous and can be land-based (80%) – dumps, littering, sewage, industrial activities – or sea-based (20%) – commercial fisheries and offshore oil and gas platforms. Ironically, the characteristics that make plastic so useful – lightness, durability, low cost and malleability – are the same that transform plastic in a long-term problem for the environment. Once in nature, plastics never disappear, they just disintegrate into smaller and smaller particles, while they quickly spread across all the geographic divisions and layers of the ocean. Plastics from all sizes can entangle marine animals and/or can be ingested by them, causing injuries, gut obstructions and death. Plastic waste is even responsible for heavy economic losses. Furthermore, microplastics are entering the human food chain and the consequences are unknown. Several existing legal instruments, of regional and international scope, are capable of addressing different aspects of marine litter. Some national initiatives are of utility as well. Nevertheless, few countries or regions have an overarching legal framework to tackle the problem. It is clear though that it is impossible to maintain the actual production and consumption patterns, and that is imperative to implement effective plastic waste management.

In the past years, the global problem of marine plastic pollution received more and more public attention. Various attempts have been made on regional, national and international level to address the issue. However, we are looking at a complex problem with various sources and pathways. Nonetheless, since most of the plastic ending up in the ocean originates from land-based activities, it seems clear that the problem has to be solved on land. This work indicates that only a holistic approach can solve the issue of marine plastic pollution, involving various actors from industry, politics and communities. However, legal research reflects, that most of the existing agreements lack effective enforcement, measurable targets and control mechanisms, therefore an efficient implementation and enforcement of existing frameworks needs to be ensured. Furthermore, we need to change our consumer behavior and no longer treat plastic as throw-away product. NGOs can play an important role in providing information and raising awareness. Moreover, it is crucial to involve local communities in protecting the marine environment and make use of their specific local knowledge. In addition to that, it’s important to help developing countries with implementing waste management systems.
Nos últimos anos, o problema global da poluição por plásticos marinhos recebeu cada vez mais atenção do público. Várias tentativas foram feitas em nível regional, nacional e internacional para resolver o problema. No entanto, estamos olhando para um problema complexo com várias fontes e caminhos. No entanto, uma vez que a maior parte do plástico que acaba no oceano tem origem em atividades terrestres, parece claro que o problema tem de ser resolvido em terra. Este trabalho indica que apenas uma abordagem holística pode resolver a questão da poluição marinha pelo plástico, envolvendo vários atores da indústria, da política e das comunidades. No entanto, a pesquisa jurídica reflete que a maioria dos acordos existentes carece de aplicação efetiva, metas mensuráveis e mecanismos de controle, portanto, uma implementação e aplicação eficientes dos quadros existentes precisa ser assegurada. Além disso, precisamos mudar nosso comportamento de consumidor e não mais tratar o plástico como um produto descartável. As ONG podem desempenhar um papel importante no fornecimento de informações e na sensibilização. Além disso, é crucial envolver as comunidades locais na protecção do ambiente marinho e utilizar os seus conhecimentos locais específicos. Além disso, é importante ajudar os países em desenvolvimento a implementar sistemas de gestão de resíduos.

O plástico, inventado há menos de dois séculos, está presente em todos os setores e atividades económicas. Este material barato e versátil promoveu uma série de avanços científicos e benefícios sociais. As suas características levaram à proliferação do seu uso a nível mundial, todavia, o seu consumo teve como consequência o aumento da poluição resultante do abandono dos seus resíduos. A poluição por resíduos de plástico é hoje um dos mais complexos problemas ambientais. Uma vez no ambiente, a degradação química e física leva à sua fragmentação. As consequências desta poluição fazem-se sentir em diversos setores, com impactos sociais, económicos e ecológicos negativos, podendo a sua ingestão ter repercussões nocivas na saúde de quem os ingere. Este problema ambiental é uma realidade que se impõe à comunidade internacional, sendo particularmente sentida no ambiente marinho. Nos últimos anos, tem aumentado o interesse da comunidade científica e do público em geral, no que diz respeito a esta problemática. A sua abordagem por parte de entidades oficiais segue diversas linhas estratégicas, com a criação de planos de ação e diretivas específicas de combate à poluição e regulação da utilização de objetos plásticos. Neste sentido, o estudo apresentado pretende analisar a dimensão do fenómeno, quais as suas fontes, consequências e o modo como as entidades europeias e nacionais têm respondido ao mesmo. Embora tenham sido criados mecanismos de resposta ao nível comunitário e nacional, estes devem ser conciliados com uma forte política de educação e sensibilização junto dos consumidores. Para tal, é necessário entender como a população vê o fenómeno da poluição por plásticos para depois traçar as linhas de ação a seguir. Assim, foi realizado um estudo de caso sobre uma amostra da população, para, posteriormente, se proceder a uma análise das perceções dos portugueses sobre o problema do lixo plástico. Através desta tipologia de estudo, será possível partir para uma abordagem mais inclusiva e adequada ao caso português e lançar as bases para uma maior adesão e sensibilização dos consumidores sobre esta questão.
Invented less than two centuries ago, plastic is present in all sectors and economic activities. This cheap and versatile material promoted a series of scientific advancements and social benefits. Its characteristics have led to a strong proliferation of its use and, worldwide, statistics. However, the consumption of this material has also resulted in an increase in pollution caused by its waste. Pollution cause from plastic waste is one of the most complex environmental problems. Once in the environment, plastics suffer the effects of chemical and physical degradation that fragment it. The consequences of plastic pollution are felt in several sectors, with negative social, economic and ecological impacts, and may also have harmful repercussions on the health of those who ingest them. This environmental problem is a reality that imposes itself on the international community, being particularly felt in the marine environment. In recent years, the interest of the scientific community and the public in general has increased, especially with regard to this problematic. Its approach by official entities follows several strategic lines, with the creation of specific action plans and directives to combat pollution and regulate the use of plastic objects. In this sense, the presented study intends to analyze the dimension of the phenomenon, what are its sources and consequences and how European and national entities have responded to it. Although response mechanisms have been created at community and national level, they must be reconciled with a strong policy of education and awareness among consumers. To this end, it is necessary to study how the population sees the phenomenon of plastic pollution and then to outline the lines of action to follow. Thus, a case study was carried out on a sample of the population, to subsequently carry out an analysis of the perceptions of the Portuguese about the problem of plastic waste. Through this type of study, it will be possible to move towards a more inclusive and adequate approach to the Portuguese case and achieve greater consumer support on this issue.