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41	Fibersläpp, vattenavvisning och färgändring hos textilier före och efter en simulerad åldring Ottosson Geete, Filippa, Larsson, Tilda, Jansson, Kajsa January 2022 (has links) Mikrofibersläpp vid tvätt lyfts ständigt som ett återkommande problem eftersom de små fragmenten leds ut i vattendragen och påverkar miljön negativt. Mängden mikroplaster är svåra att se och mäta vid endast visuell antydan. Med hjälp av en ny standard för bestämning av mikrofibersläpp finns det nu möjligheter till att bestämma mängden fibrer som lossnar påverkas vid tvätt. För att textilbranschen ska kunna bli mer hållbar krävs ytterligare undersökningar på huruvida teoretisk hållbara val av tillverkningsmetoder verkar i praktiken. Genom att använda sig av olika testmetoder för en simulerad åldring på textilier med olika infärgningsmetoder kan användningsfasens visuella och fysiska påverkan studeras, för att på så vis underlätta vid hållbara val i den textila värdekedjan. Den simulerade åldringen är anpassad efter användningsfasen av de material som används i denna studie. Skillnaden i resultat för vattenavvisningsförmåga, färghärdighet samt den mängd fibrer som lossnar under tvätt, jämförs före och efter den simulerade åldringen. Studien resulterade i att den mer hållbara metoden för infärgning av textil inte bara är teoretiskt bättre utan också genomgående presterade bättre i de tester som utförts på tygerna. Detta med undantag för resultatet i fibersläppsmetoden som efter genomförandet inte kunde jämföras enligt standarden då metoden inte kunde utföras helt korrekt. Problemet visade sig tillsynes vara värdefullt för studien då det resulterade i att det inte bara var fibrer som lossnade vid tvätt utan också beläggning, vilket ansågs vara ännu sämre. Metoden för den genomförda studien har varit användbar för att kunna dra slutsatsen att det spinnfärgade tyget fortsatt är ett mycket bättre val än det styckfärgade. Detta konstaterades efter en statistisk analysmetod av resultaten från de utförda testmetoderna men också genom den visuella indikationen. / Microfiber-pollution from washing is a recurring topic and problem because of the small fragments coming out into the water. The amount of microplastics is hard to see and measure with visual analysis, but by using the new standard method to determine the microfibres when collecting the loss of material it opens facilities to see what and how the quantity is affected. To make a more sustainable business in the textile industry, more studies about how the differences in the manufacturing processes affect the textiles have to be done. By using different test methods for a simulation of aging textiles with two different methods of coloring, the phase of use can be studied and in best case support sustainable choices in the textile value chain. The simulated aging is customized for the phase of use for the material used in this study. The results that will be analyzed are for the water repellency, color fastness and the loss of material, before and after the simulated aging. The study concluded that the more sustainable method for coloring the material is a better choice both theoretical and practical. This was found out from all the tests performed on the materials. Except for the results in the microfibre test that after being performed could not be compared according to the standard when the method could not be accomplished completely correct after problems with the filtration. Otherwise, the problem turned out to be useful for the study after being analyzed because it was not only fibers detached from the specimens but also the water repellency coating. The method for the study has been successfully useful to be able draw the conclusion that the solution dyed material is a better choice than the one being piece dyed. It was found out after the statistical analysis of the results from the performed test methods, but also through a visual indication. microfiber microplastic fiber shedding simulated ageing simulated aging ageing polyester piece dyed solution dyed mikrofiber mikroplast fibersläpp simulerad åldring åldring polyester spinnfärgning styckfärgning Engineering and Technology Teknik och teknologier
42	Stagnation Impacts on Building Drinking Water Safety: The Pandemic and Microplastics Kyungyeon Ra (13164972) 28 July 2022 (has links) <p> </p> <p>The pandemic prompted buildings globally to transition to low or no occupancy as social distancing to reduce the spread of Coronavirus Disease (COVID-19). This consequence prompted concerns about the chemical and microbiological safety of building drinking water due to stagnation. At the same time, microplastic (MP) pollution received increasing global attention due to their presence in the environment and recent discoveries within water distribution systems and at building faucets. MP sources have primarily been targeted as originating within the drinking water sources, but plastic plumbing components are less discussed and known to deteriorate into fragments and smaller pieces that reach faucets. Literature at the time of this work as sparse on stagnation impacts to drinking water quality and the fate of MPs in plumbing. In particular, health officials and building owners issued and received many differed guidance documents telling building owners do different things and no standard guideline was available to reduce the health risks caused by stagnant building drinking water. This dissertation examined three different types of buildings during closed to low water use conditions and conducted bench-scale testing to explore the phenomena observed in the field. Chapter 1 describes water quality impacts during a 7 year old ‘green’ middle school as it transitioned from Summer (low water use) to Fall (normal use). Field experiments revealed that more than half of first draw water samples exceeded the copper (acute) health-based action limit during low water use. Copper concentration within the school increased as distance from building entry point increased. Chapter 2 and 3 describe report on chemical and microbiological water quality in buildings at a university buildings (Chapter 2), and elementary school (Chapter 3). Chapters 2 and 3 revealed that stagnation negatively impacted chemical and microbiological building water quality (cold and hot) but flushing was effective at remediating high concentration of heavy metals and <em>Legionella pneumophila</em> at most locations. But in large buildings, where building plumbing system was more complicated, flushing did not always result in improved water quality. Also discovered was that water quality again deteriorated even after whole building water system was flushed. It is important to understand own building systems to maintain water quality as each building complexity requires specific knowledge and solutions. Chapter 4 describes current knowledge associated with MPs in drinking water and results of bench scale experiments on MP fate and transport in building plumbing. This work identified that while MPs have been reported at building faucets, sampling details lacking from available studies often resulted in study results not being comparable across others. Based on the review of the issue, it was found that MPs have likely reached building faucets for decades but have received no characterization until recently. Bench-scale testing using two MPs, of different density, in copper and crosslinked polyethylene (PEX) pipes revealed size influenced the amount of MPs retained in a pipe. Research needs were identified to determine the fundamental factors that control MP fate in plumbing and their presence at building faucets. </p> Water resources engineering Environmentally sustainable engineering Environmental assessment and monitoring stagnation school children drinking water legionella microplastic COVID-19 pandemic building drinking water copper lead
43	Förekomst av mikroplaster i tångmärlor (Gammaridae) längs södra Hallandskusten Karlsson, Joakim January 2020 (has links) Since the middle of the 20th century, scientists have observed that marine organisms ingest plastics in various shapes, directly or through food. Plastics smaller than 5 millimetres, called microplastics, have in recent years gained more attention and been found to accumulate environmental toxins. A family of organisms which have been found to ingest microplastics is Gammaridae, which are important as food sources and detritivores in many ecosystems. In this study, the occurrence of microplastics in marine gammarids was investigated in three rural and three urban areas, along the coast of Halland and northern Skåne. The aim was to find out if these organisms contain microplastics and to compare the occurrence in rural versus urban areas. Microplastics were found in 33 (approx. 14.9 %) of 221 samples, ranging from 0 to 3 microplastics per individual. A significant difference in the average amount of microplastics per individual was found between the rural and urban areas; the urban areas had a higher average, with one exception. In other studies, urban areas have been found to often contain more microplastics than rural areas, increasing the possibility that organisms in these areas ingest plastics. With more boat traffic and inhabitants in general, along with streams transferring plastics from inland areas, the amount of emissions in urban areas can be greater than in rural parts. The result shows that microplastics occur in marine gammarids in the 3 examined areas and that these organisms therefore may have an important part in the transfer of microplastics between trophic levels. / Sedan mitten av 1900-talet har forskare observerat att marina organismer tar in plaster i olika former, direkt eller via föda. Plastpartiklar mindre än 5 millimeter, så kallade mikroplaster, har på senare år fått större uppmärksamhet och har också visat sig kunna ackumulera miljögifter. En familj av organismer som man funnit mikroplaster i är tångmärlor (Gammaridae), vilka i många ekosystem är viktiga som födokällor och nedbrytare. I denna studie undersöktes förekomsten av mikroplaster i marina tångmärlor på tre lokaler i stadsområden respektive landsbygdsområden, längs Hallandskusten och Skånes norra kust. Syftet var att se ifall dessa organismer innehåller mikroplaster samt jämföra förekomsten i landsbygdsområden kontra stadsområden. Av 221 analyserade prov förekom mikroplaster i 33 (ca 14,9 %) och förekomsten per individ varierade från 0 till 3 mikroplaster. En signifikant skillnad i medelvärde av mikroplaster per individ fanns mellan landsbygdsområden och urbana områden; urbana områden innehöll i genomsnitt mer men med ett undantag. I andra studier har man funnit belägg för att stadsområden ofta innehåller mer mikroplaster än landsbygdsområden, något som ökar risken för att organismer i dessa områden tar in plaster. Med mer båttrafik och antal invånare överlag, tillsammans med vattendrag som för med sig plast från inlandet, kan det i dessa områden ge en större utsläppsmängd i jämförelse med i landsbygdsområden. Resultatet visar på att mikroplaster förekommer i marina tångmärlor i de undersökta områdena och att dessa organismer därmed kan vara en viktig del i överföringen av mikroplaster mellan trofiska nivåer. plastic plastics microplastics microplastic Amphipoda gammarid gammarids Gammaridae Gammarus Halland Skåne rural urban biology aquatic biology Falkenberg Ugglarp Halmstad Laxvik Båstad Kattvik Sweden trophic transfer plast plaster mikroplaster mikroplast tångmärlor tångmärla Gammaridae Gammarus gammarid gammarider märlkräfta märlkräftor Amphipoda Halland Skåne landsbygd stad biologi akvatisk biologi Falkenberg Ugglarp Halmstad Laxvik Båstad Kattvik Sverige trofisk överföring Biological Sciences Biologiska vetenskaper Other Biological Topics Annan biologi

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