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Sources, Transport, Measurement and Impact of Nano and Microplastics in Urban WatershedsBirch, Quinn T. January 2019 (has links)
No description available.
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Osud mikroplastů v půdě / Fate of microplastics in soilKameníková, Eliška January 2021 (has links)
The problems with microplastics, small plastic particles contaminating the environment, is a subject of heated discussions today. It has been recognized that the microplastics are not inert, but instead they have an impact on all enviromnental compartments. There are studies describing the negative effects of microplastics, for example on fauna and flora or on human health, but the effects on soil quality have not been sufficiently described. The aim of this thesis was to assess the short and medium term effects that microplastics could have on the soil. In this work, a series of experiments were performed to elucidate the fate of microplastics in the soil. Changes in soil organic matter thermal properties, soil respiration, amount of water and soil aggregation depending on the incubation time were monitored. Three types of agricultural land (chernozem, cambisol and phaeozem), which were contaminated with different concentrations od PET and tyre rubber, were tested. The results confirmed the specific effects of microplastics on soil properties, which were observed in non-incubated samples (i.e. at the time of incubation 0 months), microplastics did not behave inertly in the soil and affected, for example, soil properties, texture and respiration.
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Odstraňování mikroplastů z vody / Removal of microplastics from waterSkalníková, Andrea January 2021 (has links)
The aim of this diploma thesis is to investigate the removability of microplastsic particles with different shapes (fragments, sphers, fibers) by standard water treatment process, such as coagulation, filtration and sedimentation. For the experimental purpose in this study, polyvinyl chloride with a size ≤ 50 μm and a density of 1.38 g/cm3 , was used as a representative of microplastics. The coagulation has been provided by ferric sulphate in pH range 5, 6, 7 and 8 and at a diferent dose of coagulant 20, 40, and 60 mg/l. The study results has shown, that the coagulation efficiency of polyvinyl chloride particles were affected by pH. The optimal value of pH has been 7 at the coagulant dose of 20, 40 and 60 mg/l. The presence of polyvinyl chloride shown a positive effect on coagulation. It has been reflected in a reduction of the residuals of iron concentration after coagulation, at pH 5-7. Solution with polyvinyl chloride contained 1,2 mg/l dissolved organic carbon. After fitlration the concentration decreased up to 70 % at pH 7 at dose of coagulant 40 and 60 mg/l. Experiments have shown that polyvinyl chloride particles are capable of faster sedimentation after coagulation. The flocs formed during coagulation interacted effectively with the polyvinyl chloride particles and facilitate their removal...
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Temporal Dynamics In Microplastics Within An Indoor Environment: Insights From A Novel Tape-Lifting Method / Mikroplasters temporala dynamik i en inomhusmiljö: insikter från en ny tejplyftsmetodWiklund, Matilda January 2022 (has links)
Microplastics (MPs) constitute a risk to both human and environmental health. It is vital to identify sources and pathways to take the necessary action and limit the number of MPs in our environments. However, we currently have a limited understanding regarding MPs' variation with time in urban environments in an indoor setting. This knowledge gap is partly due to the absence of standard sampling procedures, and there is a need to develop reliable sampling techniques. This study evaluates the effectivity of a novel tape-lifting method developed for sampling MPs from various urban surfaces and applies this technique to measure weekly trends in artificial polymer deposition within an indoor environment at Umeå University. Two stone floor surfaces were sampled repeatedly on eight occasions over three weeks. Recovered MPs were identified in a microscope and categorized after shape: fibers or fragments. My developed tape-lifting method showed high MP recoveries (on average 100 ±4%) for the majority of the tested indoor surfaces (floors and tables). However, the method proved less functional for outdoor substrates (asphalt), where the recovery was significantly lower (on average, 48% ± 17). In my monitoring of MPs, I found that the deposition rate of fibers did not significantly differ between the two sampling sites or change over the three weeks. In contrast, MPs of fragment-type varied both between sampling sites and as a function of time. Here, the MP deposition rate was, on average, nearly two times higher at one of the sites, indicating substantial spatial variation. Regarding temporal variation, fragmented MPs showed an overall decrease in the number of deposited fragments over the three-week period. Interestingly the lack of variation in fibrous MPs indicates a dominating input source of fibers that is both homogenous for the room and static with time. In contrast, a specific source that is also time-sensitive appears to influence the dispersal pattern of fragmented MPs. My findings highlight the need to consider the temporal dimension of MP contamination and for research focusing on the relationship between fragmented MPs and their sources in indoor environments.
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Microplastics in coastal marine habitats and food websCovernton, Garth Aidan 03 May 2021 (has links)
Microplastic particles (MPs) are widely distributed in aquatic environments and present a potential risk to marine life. This thesis considers several issues relating to methodologies for sampling and analyzing MPs and the sources and fate of these particles in the marine environment, wild and farmed shellfish, and food webs of southern coastal British Columbia, Canada.
Chapter 1 introduces MPs as a contaminant, methodologies for studying them, and reviews what is known about their source, fates, and ecotoxicology in marine environments. Chapter 1 also outlines the goals of this thesis.
Chapter 2 compares the potential MP concentration estimates provided by two different seawater sampling methods. Jar samples filtered to 8-µm yielded MP concentrations averaging approximately 8.5 times higher than bucket samples filtered to 63 µm, per L of water (at the site level), driven largely by differences in the number of microfibres. An analysis of MP concentrations and mesh sizes reported in the literature suggests that using a 300–350-µm mesh may underestimate total MP concentrations by one to four orders of magnitude compared with samples filtered through much smaller mesh sizes (e.g., less than 100 µm), and despite the effect of sample volume. Particles less than 300 µm in diameter make up a large component of MPs commonly found in fish and invertebrates. As such, common sampling practices fail to adequately measure a biologically relevant class of MPs, thereby undermining the ability to quantify ecological risk.
Chapter 3 determines the influence of shellfish aquaculture activity, and its use of plastic equipment, on MPs in bivalves and their environment by comparing MP concentrations in Manila clams (Venerupis philippinarum) and Pacific oysters (Crassostrea gigas) grown on commercial shellfish beaches with those grown on non-aquaculture beaches from six areas. MP concentrations in water and sediment were also determined in four of the areas. MP concentrations did not differ between shellfish aquaculture and non-aquaculture sites for either bivalve species or for sediment and water samples. Beach sediment type had a minor effect, with more gravelly or sandier beaches associated with higher MP concentrations in oysters or clams, respectively. Oysters on sites using many synthetic anti-predator nets had more MPs than those on sites without any plastic, but analysis of particles using Fourier-transform infrared spectroscopy suggested a predominance of textile fibres including nylon and polyester, which are not typically used in shellfish aquaculture.
Chapter 4 uses stable isotope food web analysis and hierarchical Bayesian generalized linear mixed models to explore whether bioaccumulation and biomagnification are occurring in coastal marine food webs at three locations. Bioaccumulation was higher for smaller-bodied suspension feeding animals such as bivalves. However, biomagnification was not occurring in animal digestive tracts, and trophic dilution was demonstrated in fish livers. Trophic transfer was shown to occur between prey and predator for rockfish, but higher concentrations in full stomachs compared with empty ones suggested rapid excretion of ingested MPs.
Chapter 5 supplies some general conclusions on the status of MPs in the British Columbian environment, as well as risks to seafood consumers. It also explores future work that will be needed to understand the complex ecotoxicology of MPs. / Graduate / 2022-04-12
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The Association between Stomach Fullness and Vertical Migration Behavior in Deep-Pelagic Crustaceans and Fishes in the Gulf of Mexico, with Notes on Microplastic IngestionBos, Ryan P 15 April 2019 (has links)
This thesis presents: 1) the first statistically rigorous support for the longstanding hypothesis that state of satiation modifies diel vertical migration patterns of deep-sea micronektonic crustaceans and fishes; and, 2) the first assessment of microplastic ingestion by deep-pelagic micronekton in the Gulf of Mexico and Straits of Florida. Deep-sea pelagic crustaceans and fishes significantly contribute to abundance and biomass of pelagic ecosystems, are frequently consumed by commercially valuable fishery species, and serve to transport both nutrients and pollutants between shallow and deep waters. The results presented herein will be valuable for assessing risk associated with potential biomagnification of plastic through consumption or indirect consumption of deep-sea biota. Moreover, these data demonstrate that the extent of feeding at depth by non-migratory taxa as well as non-migrating individuals of migratory taxa is substantial. Feeding at depth is usually excluded from biogeochemical models, and these data demonstrate that this is an important factor that must be included to obtain more precise estimates of active nutrient flux by micronekton.
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Identification and Characterization of Microfibers in Wastewater Discharging into Lake ErieHouck, Blane 10 May 2019 (has links)
No description available.
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Spreading of microplastics from artificial turf via stormwater / Spridning av mikroplaster från konstgräsplaner via dagvattenLundström, Johanna January 2019 (has links)
På senare tid har mikroplaster i hav och sjöar uppmärksammats som ett potentiellt stortmiljöproblem. Idag finns mikroplaster spridda över hela världens vatten från polerna till ekvatorn.År 2016 uppmärksammades konstgräsplaner som den nästa största källan till spridning avmikroplaster till sjöar och vattendrag i Sverige [1]. Fotboll är Sveriges nationalsport och är densporten som står för flest aktivitetstimmar i Sverige. Konstgräs har gjort det möjligt för fler barnoch ungdomar att få fler speltimmar och idag spelar 90 % av alla fotbollsspelare på konstgräs [2].De olika spridningsvägarna för mikroplaster från konstgräsplaner undersöktes med fokus påspridningsvägen via dagvatten. Det finns fler olika reningsmetoder för dagvatten innehållandemikroplaster, en av dessa är granulatfällan, en filterpåse som placeras i en dagvattenbrunn för attfånga upp granulat och konstgräsfibrer som sprids från konstgräsplanen till dagvattenbrunnen.Syftet med denna studie var att optimera reningsmetoden granulatfälla utifrån möjligavattenflöden och dess effektivitet i att fånga upp mikroplaster. Detta undersöktes genomframtagandet av en vattenflödesmodell vid konstgräsplaner med variationer i konstruktion ochgenom fältstudier av granulatfällans effektivitet vid två konstgräsplaner i Storstockholm.Det regn som undersöktes i vattenflödesmodellen var extremregn för ett 10 års regn under 10minuter. Detta för att hitta det maximala flöde granulatfällorna kommer behöva klara av. Vilkavattenflöden som nådde dagvattenbrunnarna var beroende på antalet dagvattenbrunnarplacerade runt konstgräsplanen, i vilket område i Sverige som konstgräsplanen var placerad, detvill säga hur mycket regn som kom, och konstgräsplanens infiltrationsförmåga.Vattenflödesmodellen fungerar som en mall för möjliga vattenflöden vid en specifik plats i Sverigeoch en viss konstruktion av konstgräsplan.De konstgräsplaner som var med i fältstudierna var Skytteholms IP i Solna och Spånga IP iStockholm. Vid varje konstgräsplan placerades 6 granulatfällor med två filterpåsar på varje fälla,den inre med större maskor och den yttre med mindre maskor. Kombinationerna var 200 μm med100 μm, 200 μm med 50 μm och 100 μm med 50 μm. Totalt fångades 10,3 kg mikroplast vidSkytteholms IP och 1,5 kg vid Spånga IP under de 49 dygn granulatfällorna var utplacerade. Avden totala mängden mikroplast viktmässigt i varje granulatfälla fanns minst 99 % i den inrefilterpåsen och maximalt 1 % i den yttre filterpåsen, det vill säga i storleksfraktionen mellan denyttre och den inre filterpåsen.Slutsatserna från denna studie är att vattenflödet till dagvattenbrunnarna placerade runtkonstgräsplaner kan variera mycket på grund av hur konstgräsplanen är konstruerad. Det berorframförallt på konstgräsplanens infiltrationsförmåga och antal dagvattenbrunnar runtkonstgräsplanen. Utifrån de teoretiska vattenflödena och fältstudierna rekommenderas att enfilterpåse med maskstorlek 200 μm används i granulatfällan. Detta utifrån att den inre filterpåsenfångade minst 99 % av de mikroplaster som nådde granulatfällorna, som var större än 50 μm, ochökad risk för igensättning och tillväxt av biofilm på filterpåsarna med mindre maskor. Vidarestudier bör genomföras på granulatfällans vattenflöde över tid, mikroplaster mindre än 50 μm,IIandra spridningsvägar för mikroplaster från konstgräsplaner, förbättrade konstruktioner avkonstgräsplaner och förbättrat underhållningsarbete för att minska spridningen av mikroplasterfrån konstgräsplaner. / In the recent years microplastics in the marine environment has been recognized as a potentiallyimportant environmental issue. Today there are microplastics spread in the waterbodies all overthe world, from the equator to the poles in south and north. In 2016 artificial turf was labeled thesecond largest source of microplastics to the marine environment in Sweden [1]. Football is thenational sport of Sweden and accounts for the majority of the activity hours among the youth inSweden. The artificial turf has made it possible for more children to play football and for them toget more hours on the field. Today about 90 % of the football players play on artificial turf [2].The microplastics pathways to the nature and the marine environment were studied andtreatment methods were developed. One of these methods is the so called granule trap, a filterbag which is placed in a stormwater drainage well to catch the rubber granulates and the artificialturf fibers which can be spread from the artificial field to the drainage system. The aim of thisstudy was to optimize the granule trap for possible waterflows to the stormwater drainage welland its efficiency to catch microplastics. This was researched through field studies of the efficiencyof the granule trap at two artificial turfs in Stockholm and the development of a waterflow modelof an artificial turf with varying construction.The rainfall which was used in the waterflow model was the 10-year storm with a duration of 10minutes. This to find the maximum waterflow the granuletraps must manage. The waterflows tothe stormwater drainage well were dependent on the number of wells placed around the artificialturf, in which area of Sweden the football field was placed, in other words the amount of rain thatfell, and the infiltration capacity of the artificial turf. The waterflow model works as a templatefor possible waterflows at an artificial turf with a certain construction and at a certain location inSweden.The artificial turfs which were examined in the field studies were Skytteholms IP in Solna andSpånga IP in Stockholm. At each football field 6 granuletraps were placed, each loaded with twofilter bags, the inner with larger sized mesh and the outer with smaller sized mesh. The mesh sizecombinations were 200 μm with 100 μm, 200 μm with 50 μm and 100 μm with 50 μm. atSkytteholms IP a total amount of 10.3 kg microplastics were caught and at Spånga IP a total of 1.5kg microplastics were caught during the 49 days the granuletraps were placed at the footballfields. Out of the total amount of microplastics in each granuletrap at least 99 % by mass was inthe inner filter bag and maximum 1 % by mass was in the outer filter bag, in the size fractionbetween the outer and the inner filter bag..In conclusion this study shows that the waterflow to the stormwater drainage wells placed aroundthe artificial turfs vary a lot depending on the construction of the artificial turf. Foremost itdepends on the infiltration capacity of the artificial turf and the number of stormwater drainagewells around the field. With regards to the waterflows from the waterflow model and the resultsfrom the field studies the recommended mesh size for the filter bags is 200 μm. This since at least99 % by mass of the microplastics, which were larger than 50 μm, that reached the granule trapsIVwere trapped in the inner filter bag and the elevated risk of clogging and biofilm growth on thefilter bags with smaller mesh size. Further studies should be conducted on the waterflow throughthe granuletraps over time, microplastics smaller than 50 μm, other pathways for themicroplastics away from the artificial turf, improved constructions of artificial turfs and improvedmaintenance on the artificial turfs to reduce the risk of spreading of microplastics from artificialturfs.
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MICROPLASTICS IN BIOTIC AND ENVIRONMENTAL SAMPLES TAKEN NEAR TWO MUNICIPAL WASTEWATER TREATMENTS PLANTS IN THE GRAND RIVER, ONTARIOWeir, Ellie January 2021 (has links)
Microplastics are present in municipal wastewater treatment plant (WWTP) effluents; however, it is unclear whether these contaminants are ingested by biota living downstream of these outfalls. This study examined whether microplastic levels in caged biota, resident fish, and environmental samples were elevated near the Waterloo and Kitchener WWTP outfalls along the Grand River in the fall of 2019. Amphipods (Hyalella azteca), fluted-shell mussels (Lasmigona costata), and rainbow trout (Oncorhynchus mykiss) were caged at one upstream reference site and two impacted sites downstream of the Kitchener WWTP for 14 (amphipods and trout) or 28 (mussels) days. Rainbow darter (Etheostoma caeruleum) were collected using a backpack electrofisher from 10 sites up and downstream of both the Kitchener and Waterloo WWTPs, along with surface water and sediment samples. Whole body Hyalella, fish digestive tracts, and fluted-shell mussel tissues (hemolymph, digestive glands, and gills) were digested in 20% potassium hydroxide. Environmental samples were processed using filtration and density separation, then visual identification of microplastics was done. Elevated particle counts were found in rainbow trout digestive tracts at the Kitchener outfall site, compared to the upstream reference and downstream farfield sites. Additionally, particle concentrations in sediment were significantly higher at the Waterloo outfall, compared to all other sites (except for one upstream location). However, whole Hyalella, fluted-shell mussel tissues (hemolymph, digestive glands, and gills), digestive tracts of rainbow darter, and surface waters did not show elevated counts downstream of these discharges. Across all samples, fibers were the most common morphology, and blue and clear particles were prevalent in samples collected near WWTPs. Overall, these findings suggest that the Kitchener and Waterloo WWTPs could be important sources of particles to the Grand River, adding to our understanding of the fate of this contaminant in freshwater ecosystems. / Thesis / Master of Science (MSc)
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Mikroplastutsläpp från däckslitage : Ett rullande utsläpp / Release of microplastics from tyre wear : Rolling emissionsAgewall, John, Wallgren, Kim January 2019 (has links)
Antalet bilar har ökat stadigt genom åren och i mars 2019 befann sig nästan 4,9 miljoner personbilar i aktiv användning i Sverige. Något som inte får lika mycket uppmärksamhet som koldioxidutsläpp från trafiken och slitage av vägar är slitaget av bildäck. Regeringen har därmed tillsatt ett uppdrag där mängden mikroplastutsläpp ska kvantifieras, sprida kunskap om problemet och utveckla åtgärder mot utsläppen. En av myndigheterna som fått detta uppdrag är Statens väg- och transportforskningsinstitut (VTI), med vilka detta arbete genomfördes. Arbetet går ut på att försöka kvantifiera utsläppen av mikroplastutsläpp från personbilar samt undersöka vilka typer av slitage som är vanligast förekommande. Rapporten består av två delar, en litteraturstudie som ska ge en klar bild av nuläget, typer av däck, vad mikroplaster är samt varför slitage uppstår. Under den andra delen genomfördes mätningar på kasserade däck, där mönsterdjupsprofiler, vikt, mönsterdjup, DOT märkning, modell, märke, typ av däck och dimensioner antecknades. Med hjälp av profilerna och originaldata som tillhandahölls av olika däcktillverkare kunde de vanligaste slitagen bestämmas och den bortslitna vikten och volymen kunde uppskattas. De vanligaste typerna av slitage är centrum-, jämnt- och sidoslitage, vilket beror på för högt lufttryck i däcken, samt fel hjulinställningar. Den totala årliga mängden utsläpp av mikroplaster från personbilar uppskattades ligga mellan 8 300 och 16 700 ton. / The number of cars has been on a steady increase in Sweden and in mars 2019 there were almost 4,9 million cars in active use. Nowadays most of the attention is focused on pollution through carbon dioxide and the wear of roads. However, a problem that often goes unrecognized is the tear of car tyres and the release of microplastics into the environment. In order to quantify the amount of microplastics released into the environment, the Swedish government has instructed The Swedish National Road and Transport Research Institute (VTI) to carry through with this. The aim of this report is to, with the help of VTI, try to quantify the amount of microplastics released from private car traffic and examine the main types of tyre wear. This report consists of two parts, one study of what microplastics is and how tyre wear arises. The second part consists of measuring, where used tyres have had their weight and tread measured. The profile of the tear, DOT number, production date, model, dimensions and type of tyre is additional data that was collected. Through the use of data provided by the tyre companies and the collected data, the total loss of weight and volume together with a yearly weight and volume loss could be calculated. Through analysis of the tyre profiles and their tread depths the most occurring type of wear patterns was determined, which were central, even and side wear. The estimated yearly amount of microplastics released in Sweden was between 8 300 and 16 700 tonnes.
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