Literatura académica sobre el tema "Microplastics quantification"
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Artículos de revistas sobre el tema "Microplastics quantification"
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Li, Daoji, Guyu Peng y Lixin Zhu. "Progress and prospects of marine microplastic research in China". Anthropocene Coasts 2, n.º 1 (1 de enero de 2019): 330–39. http://dx.doi.org/10.1139/anc-2018-0014.
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Research on microplastics in China is progressing rapidly. Within recent years, more than 30 research institutes have conducted research on marine microplastic in estuaries, coasts, open sea, and Polar regions. Microplastics have been detected in freshwater systems (lakes, rivers, and wastewater treatment plants) and coastal and marine environments. This paper reviews the research progress of microplastics in China, providing information on topics including the methodology, quantification of microplastics in various habitats, eco-toxicological effect, biodegradation, management, and control of plastic waste and microplastics. This paper discusses the sampling and analysis of microplastic in different media, followed by spatial and temporal distribution of microplastics in marginal seas and coastal and freshwater systems. After summarizing the recent advances on toxicology research and risk assessment of microplastics, this paper provides suggestions for future study to provide baseline information for better risk assessment and improved understanding of the lifecycle of microplastics in the environment.
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Massarelli, Carmine, Claudia Campanale y Vito Felice Uricchio. "A Handy Open-Source Application Based on Computer Vision and Machine Learning Algorithms to Count and Classify Microplastics". Water 13, n.º 15 (31 de julio de 2021): 2104. http://dx.doi.org/10.3390/w13152104.
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Microplastics have recently been discovered as remarkable contaminants of all environmental matrices. Their quantification and characterisation require lengthy and laborious analytical procedures that make this aspect of microplastics research a critical issue. In light of this, in this work, we developed a Computer Vision and Machine-Learning-based system able to count and classify microplastics quickly and automatically in four morphology and size categories, avoiding manual steps. Firstly, an early machine learning algorithm was created to count and classify microplastics. Secondly, a supervised (k-nearest neighbours) and an unsupervised classification were developed to determine microplastic quantities and properties and discover hidden information. The machine learning algorithm showed promising results regarding the counting process and classification in sizes; it needs further improvements in visual class classification. Similarly, the supervised classification demonstrated satisfactory results with accuracy always greater than 0.9. On the other hand, the unsupervised classification discovered the probable underestimation of some microplastic shape categories due to the sampling methodology used, resulting in a useful tool for bringing out non-detectable information by traditional research approaches adopted in microplastic studies. In conclusion, the proposed application offers a reliable automated approach for microplastic quantification based on counts of particles captured in a picture, size distribution, and morphology, with considerable prospects in method standardisation.
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Woo, Hyunjeong, Kangmin Seo, Yonghyun Choi, Jiwon Kim, Masayoshi Tanaka, Keunheon Lee y Jonghoon Choi. "Methods of Analyzing Microsized Plastics in the Environment". Applied Sciences 11, n.º 22 (11 de noviembre de 2021): 10640. http://dx.doi.org/10.3390/app112210640.
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Microplastics are found in various environments with the increasing use of plastics worldwide. Several methods have been developed for the sampling, extraction, purification, identification, and quantification of microplastics in complex environmental matrices. This study intends to summarize recent research trends on the subject. Large microplastic particles can be sorted manually and identified through chemical analysis; however, sample preparation for small microplastic analysis is usually more difficult. Microplastics are identified by evaluating the physical and chemical properties of plastic particles separated through extraction and washing steps from a mixture of inorganic and organic particles. This identification has a high risk of producing false-positive and false-negative results in the analysis of small microplastics. Currently, a combination of physical (e.g., microscopy), chemical (e.g., spectroscopy), and thermal analyses is widely used. We aim to summarize the best strategies for microplastic analysis by comparing the strengths and limitations of each identification method.
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Wander, L., L. Lommel, K. Meyer, U. Braun y A. Paul. "Development of a low-cost method for quantifying microplastics in soils and compost using near-infrared spectroscopy". Measurement Science and Technology 33, n.º 7 (12 de abril de 2022): 075801. http://dx.doi.org/10.1088/1361-6501/ac5e5f.
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Abstract Near-infrared (NIR) spectroscopy is a promising candidate for low-cost, nondestructive, and high-throughput mass quantification of microplastics in environmental samples. Widespread application of the technique is currently hampered mainly by the low sensitivity of NIR spectroscopy compared to thermoanalytical approaches commonly used for this type of analysis. This study shows how the application of NIR spectroscopy for mass quantification of microplastics can be extended to smaller analyte levels by combining it with a simple and rapid microplastic enrichment protocol. For this purpose, the widely used flotation of microplastics in a NaCl solution, accelerated by centrifugation, was chosen which allowed to remove up to 99% of the matrix at recovery rates of 83%–104%. The spectroscopic measurements took place directly on the stainless-steel filters used to collect the extracted particles to reduce sample handling to a minimum. Partial least squares regression models were used to identify and quantify the extracted microplastics in the mass range of 1–10 mg. The simple and fast extraction procedure was systematically optimized to meet the requirements for the quantification of microplastics from common polyethylene-, polypropylene-, and polystyrene-based packaging materials with a particle size <1 mm found in compost or soils with high natural organic matter content (>10% determined by loss on ignition). Microplastics could be detected in model samples at a mass fraction of 1 mg g−1. The detectable microplastic mass fraction is about an order of magnitude lower compared to previous studies using NIR spectroscopy without additional enrichment. To emphasize the cost-effectiveness of the method, it was implemented using some of the cheapest and most compact NIR spectrometers available.
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Tesán Onrubia, Javier A., Kahina Djaoudi, Franco Borgogno, Susanna Canuto, Bernard Angeletti, Giovanni Besio, Marco Capello et al. "Quantification of Microplastics in North-Western Mediterranean Harbors: Seasonality and Biofilm-Related Metallic Contaminants". Journal of Marine Science and Engineering 9, n.º 3 (19 de marzo de 2021): 337. http://dx.doi.org/10.3390/jmse9030337.
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The Mediterranean Sea is one of the most impacted basins in terms of microplastics pollution. Land-based activities are the major sources of plastic litter to the ocean, with harbors probably representing significant hotspots. In the framework of the SPlasH! project (Stop alle Plastiche in H2O, Interreg Marittimo project), microplastics were sampled in three north-western Mediterranean harbors during summer and winter. In this study, the areal concentrations of microplastics ranged from 5576 to 379,965 items·km−2. A decreasing gradient was observed from the inner to the outer zones of the studied harbors, pointing out these enclosed systems as hotspots regarding microplastic pollution. During summer, the areal concentrations of microplastics were higher than in winter, which could be explained by an enhancement of port activities leading to MPs production. The investigation of microplastics size classes distribution in the surface waters revealed that microplastics within the size range between 300 µm and 500 µm were the least represented. In this study, we assessed trace metal (Pb, Fe, Cu, V, Cd and As) bioaccumulation by the biofilm which developed on the surface of microplastics. The results highlighted that concentrations within the biofilm were higher than those in the surrounding waters. This result strongly suggested trace metal bioaccumulation on microplastics through biofilm formation. When trace metal concentrations were normalized over the corresponding surface of microplastics and macroplastics, higher values were obtained for microplastics, evidencing their enhanced capacities to bioaccumulate contaminants when compared to macroplastics.
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Bilugan, Quennie Morales, Jomel Saraza Limbago y Redel L. Gutierrez. "Detection and quantification of microplastics from cultured green mussel Perna viridis in Bacoor Bay, Cavite, Philippines". Sustinere: Journal of Environment and Sustainability 5, n.º 2 (31 de agosto de 2021): 90–102. http://dx.doi.org/10.22515/sustinere.jes.v5i2.166.
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Microplastic contamination in the aquatic environment is a worldwide problem endangering aquatic organisms and human health. However, few reports were published in the Philippines especially in different edible fishery products. Hence, an investigation to report its prevalence in edible fishery products, especially in a fishery-dependent country, is necessary. This study was conducted to detect, characterize, and quantify microplastics from cultured Green mussel Perna viridis in Bacoor Bay, Cavite, Philippines. Samples (n=63) were collected from the inner, middle, and outer parts of Bacoor Bay. Isolation and characterization were conducted using wet peroxide oxidation-assisted density separation and stereomicroscopy, respectively. Results show a low concentration of microplastics from P. viridis cultured in Bacoor Bay. The highest microplastic count was observed from the inner bay (0.41 particle/gwet weight) followed by the middle bay (0.40 particle/gwet weight), then the outer bay (0.27 particle/gwet weight). The majority of microplastics in all sites were fibers (61%), color red (29%), and were dominated with > 10 to 50 µm length. This study revealed that microplastic is prevalent in Bacoor bay. Further study on confirming the microplastic polymers from P. viridis cultured in Bacoor bay is recommended.
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Umar, Muhammad, Cecilie Singdahl-Larsen y Sissel Brit Ranneklev. "Microplastics Removal from a Plastic Recycling Industrial Wastewater Using Sand Filtration". Water 15, n.º 5 (26 de febrero de 2023): 896. http://dx.doi.org/10.3390/w15050896.
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The removal of microplastic from wastewater collected from a plastic recycling facility was investigated, using a laboratory scale sand-filter. Wastewater samples were collected before and after the onsite sand-filter, for characterization for different polymer types, sizes, and shapes. A considerable difference in the characteristics and concentrations of microplastics was observed before and after onsite sand-filtration, demonstrating differences in the source of microplastics and/or potential contamination of the sand-filter operated at the facility. The distribution of different polymers showed polyethylene and polypropylene to be the main microplastics present in the wastewater samples. In the next stage, the samples were passed through a laboratory scale sand-filter column, to investigate the removal of microplastics. The laboratory scale sand-filter showed high efficiency (up to 100%) in removing microplastics of all polymer types, shapes, and sizes, demonstrating the effectiveness of this well-developed, and widely adopted, method for the removal of microplastics from wastewater. As the green shift and circular economy will result in more plastics being recycled, this study demonstrates the need for quantification of microplastic in effluents from plastic recycling facilities. This is important for devising appropriate microplastic removal strategies, and meeting potential discharge regulations that may come into effect in the future.
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Choi, Sola, Miyeon Kwon, Myung-Ja Park y Juhea Kim. "Analysis of Microplastics Released from Plain Woven Classified by Yarn Types during Washing and Drying". Polymers 13, n.º 17 (3 de septiembre de 2021): 2988. http://dx.doi.org/10.3390/polym13172988.
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Microplastics reach the aquatic environment through wastewater. Larger debris is removed in sewage treatment plants, but filters are not explicitly designed to retain sewage sludge’s microplastic or terrestrial soils. Therefore, the effective quantification of filtration system to mitigate microplastics is needed. To mitigate microplastics, various devices have been designed, and the removal efficiency of devices was compared. However, this study focused on identifying different fabrics that shed fewer microplastics. Therefore, in this study, fabric-specific analyses of microplastics of three different fabrics during washing and drying processes were studied. Also, the change in the generation of microplastics for each washing process of standard washing was investigated. The amount of microplastics released according to the washing process was analyzed, and the collected microplastics’ weight, length, and diameter were measured and recorded. According to the different types of yarn, the amount of microplastic fibers produced during washing and drying varied. As the washing processes proceed, the amount of microplastics gradually decreased. The minimum length (>40 µm) of micro-plastics generated were in plain-woven fabric. These results will be helpful to mitigate microplastics in the production of textiles and in selecting built-in filters, and focusing on the strict control of other parameters will be useful for the development of textile-based filters, such as washing bags.
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Mahidin, Asri Gani, Saiful, Muhammad Irham, Wulan Windari y Erdiwansyah. "An overview of the potential risks, sources, and analytical methods for microplastics in soil". AIMS Environmental Science 9, n.º 2 (2022): 169–200. http://dx.doi.org/10.3934/environsci.2022013.
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<abstract> <p>Contaminants from microplastics in the soil can pose a huge and potential risk to global ecological systems. Microplastic contaminants have become an issue since the source and potential risks have gained a point of great concern. This problem is due to the lack of a comprehensive and systematic analysis system for microplastics. Thus, a comprehensive review of microplastic knowledge is carried out to detect its potential risks, occurrences, sources, and characteristics. The study results show that microplastics have been found everywhere, as shown in the global matrix. However, with the advancement of increasingly sophisticated technology, the microplastics found in the soil can be reduced. The difficulties of analytical systems inherent in particles in even complex matrices can be overcome with technology. Research on the distribution and emergence of microplastics is still very slow in several countries, including Indonesia, the United States, and Africa. The composition and characteristics of microplastics in soil and the environment shows their consistency still indicates a change in source. Microplastics in the soil have extensive and diverse sources, leading to high accumulation. This study also discusses the potential risks and effects of microplastics on soil ecosystems. The interaction and combination of contaminants from adsorbed microplastics can lead to soil fertility and migration systems in the food chain. The impact of microplastics on soil depends on chemical components, natural factors, and morphology. Thus, regional quantification and estimation of emissions from microplastics have a huge gap. In addition, the concentration of microplastics and the masking of microplastics to store carbon in the soil can be influenced by natural factors and require various efforts.</p> </abstract>
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Hernández Fernández, Joaquín, Heidis Cano, Yoleima Guerra, Esneyder Puello Polo, John Fredy Ríos-Rojas, Ricardo Vivas-Reyes y Juan Oviedo. "Identification and Quantification of Microplastics in Effluents of Wastewater Treatment Plant by Differential Scanning Calorimetry (DSC)". Sustainability 14, n.º 9 (20 de abril de 2022): 4920. http://dx.doi.org/10.3390/su14094920.
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In this research, the presence of microplastics was detected through a differential scanning calorimetry (DSC) analysis of three wastewater treatment plants. One of these plants applied only a preliminary treatment stage while the others applied up to a secondary treatment stage to evaluate their effectiveness. The results showed the presence of polyethylene (PE), polystyrene (PS), polypropylene (PP) and polyethylene terephthalate (PET), which were classified as fragments, fibers or granules. During the evaluation of the plants, it was determined that the preliminary treatment did not remove more than 58% of the microplastics, while the plants applying up to a secondary treatment with activated sludge achieved microplastic removal effectiveness between 90% and 96.9%.
Tesis sobre el tema "Microplastics quantification"
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NAVA, VERONICA. "Microplastics in freshwater systems: characterization, quantification and interaction with aquatic organisms". Doctoral thesis, Università degli Studi di Milano-Bicocca, 2022. http://hdl.handle.net/10281/363436.
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Gli ecosistemi acquatici risentono di differenti impatti antropici. Tra questi, la presenza di plastiche e microplastiche rappresenta una problematica ambientale diffusa. La maggior parte delle ricerche svolte fino ad ora si è concentrata specialmente sull’ambiente marino e le informazioni riguardanti la presenza e gli effetti di questi contaminanti nei sistemi di acqua dolce sono limitate. Inoltre, non esiste ancora nella comunità scientifica un’armonizzazione delle procedure di campionamento e dei protocolli analitici per la caratterizzazione e quantificazione delle plastiche in ambiente acquatico. Questo rende il confronto dei dati ottenuti da ricerche differenti complesso. Oltre a questi aspetti, sono necessari ulteriori studi per comprendere l’influenza che le (micro)plastiche possono esercitare sugli organismi e sul funzionamento degli ecosistemi acquatici. In particolare, le informazioni relative agli effetti sugli organismi dei più bassi livelli trofici sono molto limitate. Dato questo contesto, nella presente tesi di dottorato sono illustrati quattro lavori che hanno contribuito ad aumentare le informazioni disponibili sulle (micro)plastiche in ambienti di acqua dolce. Il primo lavoro si è concentrato sull’utilizzo della micro-spettroscopia Raman per l’identificazione della composizione polimerica dei materiali plastici, la cui determinazione è fondamentale per una corretta e adeguata caratterizzazione di questi inquinanti. Al fine di aumentare le conoscenze relativamente a questa tecnica, è stato sviluppato e descritto un database, liberamente fruibile, di spettri di diversi polimeri plastici ed additivi che possono essere comunemente individuati in ambiente. Inoltre, è stato anche sviluppato un nuovo pacchetto in R che fornisce diversi strumenti per l’analisi e l’identificazione di spettri. I vantaggi e gli svantaggi della spettroscopia Raman sono stati evidenziati e sono state fornite utili indicazioni per studi futuri. Il secondo lavoro si è invece concentrato sulla determinazione e caratterizzazione di plastiche e microplastiche nelle acque superficiali di laghi di diverse regioni del mondo. Infatti, sono stati analizzati campioni provenienti da 38 laghi (distribuiti in 28 Stati), selezionati in modo da essere rappresentativi di diverse condizioni limnologiche e differente grado di impatto antropico. I campioni sono stati prelevati seguendo una procedura standardizzata che ha permesso di ottenere in questo modo dati realmente confrontabili. Con questo dataset globale sono state valutate non solo le concentrazioni ma anche le caratteristiche delle particelle plastiche. Inoltre, l’analisi dei dati ha permesso di evidenziare la presenza di una relazione positiva tra la concentrazione di (micro)plastiche e attributi del bacino idrografico, espressione di impatto antropico. Oltre a ciò, è stato evidenziato come laghi profondi, con estesa area superficiale ed elevato tempo di ritenzione delle acque tendano ad accumulare un numero maggiore di microplastiche. Nell’ultima parte della tesi, è stata invece investigata la relazione tra microplastiche e microalghe. Questo argomento è stato approfondito attraverso un duplice approccio: dapprima è stata svolta un’estesa ricerca bibliografica e successivamente è stata condotta una sperimentazione in mesocosmi per valutare la colonizzazione di diversi polimeri plastici in ambienti con differenti caratteristiche chimico-fisiche e ambientali. Questo esperimento ha permesso di evidenziare come le microplastiche siano in grado di supportare la crescita di molte e diverse specie microalgali. Non è stata però evidenziata una specificità nella colonizzazione di polimeri differenti. Infatti, è stato mostrato come, non la composizione polimerica del substrato, ma le specie esistenti nei diversi mesocosmi e le differenti condizioni ambientali rappresentino i principali fattori che determinano ed influenzano la composizione specifica del biofilm algale.Among the multiple stressors that affect aquatic ecosystems, plastic pollution is deemed a widespread and pervasive environmental issue. The majority of the research has been conducted in marine environments and information about the occurrence and effects of these pollutants in freshwater systems is scattered. Moreover, there is a lack of consensus on sampling and analytical procedures for their characterization and quantification, which makes comparison among studies difficult. Besides, more research is needed to assess the influences of plastics and microplastics on ecosystem functions and aquatic organisms, especially focusing on lower trophic levels. Given these gaps, the present project describes four pieces of work that contribute to enhancing our knowledge about plastics and microplastics in freshwater ecosystems. Firstly, since polymer identification constitutes a fundamental step in plastic analysis, the suitability of Raman spectroscopy for polymeric characterization was examined, and a free database with Raman spectra of plastics complemented by a new R package with tools for their processing were developed and described. Advantages and drawbacks of this technique were discussed, with a particular emphasis on plastic additives, which are contained in the majority of polymers but are still poorly investigated, and a catalog with detailed information about peaks of most common plastic polymers was reported to provide guidance for further studies. Secondly, microplastic occurrence in surface water of different freshwater systems was assessed. Indeed, water samples of 38 lakes from 28 different countries covering an assortment of limnologically diverse freshwater ecosystems under varying levels of anthropogenic stress were collected, following a common protocol. This global investigation allowed obtaining comparable data about plastic concentration and features. Moreover, the results suggested the existence of a relationship between urban-related attributes of lakes/watersheds and the plastic concentration but also highlighted as large and deep lakes with high retention times accumulated plastic debris at higher concentrations. Lastly, the relationship between microplastics and microalgae was investigated. This was pursued by combining a critical review of the literature with an experimental approach aimed at analyzing the phytobenthos establishment on two different plastic polymers using a multi-site mesocosm system. This experiment highlighted that microplastics supported the growth of a rich and diversified community of microalgae, showing that many species could coexist on the surface of relatively small plastic items. Species-specificity in the colonization of the different plastic polymers was not observed. Indeed, local species pool and nutrient concentration rather than polymeric composition seemed to be the determinant factors defying the community diversity.
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Ziajahromi, Shima. "Identification and quantification of microplastics in wastewater treatment plant effluent: Investigation of the fate and biological effects". Thesis, Griffith University, 2018. http://hdl.handle.net/10072/378550.
Texto completoResumen
Microplastics (i.e., plastics particles < 5mm) are widespread emerging contaminants
that have been detected in various aquatic environments worldwide including
freshwater and marine ecosystems. Contamination of the environment with
microplastics has become an environmental issue due to the potential of plastics to
remain for thousands of years and to accumulate in the aquatic environment. The
abundance of microplastics in the aquatic environment is assumed to increase due to
continuous fragmentation of macro and microplastic debris, which can lead to a
decrease in the average size ranges of microplastics over time (Cole et al., 2011).
Moreover, concerns have been raised regarding the potential of microplastics to
physically (e.g., blockage of digestive tract) and chemically (e.g., leaching of sorbed
chemicals and toxic additives) harm aquatic organisms.
Microplastics can enter the aquatic environment from both aquatic-based and landbased
sources. Recently, wastewater treatment plants (WWTP) have been identified
as one of the important land-based sources of microplastics. While microplastics
have been reported in WWTP effluent in Asia, Europe, USA and Russia, little is
known about the presence of microplastics in Australian WWTP effluent. More
importantly, the lack of standardized techniques to sample and characterize
microplastics in environmental samples, especially in complex samples such as
wastewater, has led to inaccurate estimations of microplastic concentrations. In
response to the current knowledge gaps, a novel validated high-volume sampling
device was developed for in situ fractionation of microplastics from wastewater
effluent as part of this project. The developed method was applied to three Australian
WWTPs utilizing primary, secondary and tertiary treatments to provide a snapshot of
the fate and removal of microplastics during various wastewater treatment processes.
To achieve an accurate estimation of microplastics, the sampling technique was
combined with an efficient sample processing method. Microplastic polymer type,
shape and potential origin were further determined using microscopy analysis and
Fourier Transform Infrared (FTIR) spectroscopy. The efficiency of the sampling
device was found to be between 92 to 99% for 500 and 25 μm mesh screens. The
results showed that the concentrations of microplastics were 1.5, 0.6 and 0.2
microplastics per liter of effluent in primary, secondary and tertiary effluent,
respectively. It was also found that the majority of detected microplastics in the
studied WWTPs were polyethylene terephthalate (PET) fibers, which is assumed to
originate from synthetic clothing. Polyethylene (PE) beads and fragments, which may be associated with cosmetic products, were the second most frequently detected
type of microplastic. Despite a thorough sample processing method, FTIR
spectroscopy revealed that between 22 to 90% of the suspected microplastic particles
were in fact non-plastic particles. This study suggests that WWTPs can act as a
significant source of microplastics to the aquatic environment given the large volume
of wastewater discharged to the aquatic environment.
To date, the effects of microplastics on aquatic organisms have mostly been
examined using high and often unrealistic concentrations of microplastics (e.g.,
milligram per liter range). Moreover, while the presence of different types of
microplastics together in aquatic ecosystems has been widely reported, the potential
effects of microplastics when they occur as mixtures are largely unknown. To cover
these knowledge gaps, the potential adverse effects of wastewater-based
microplastics (such as fibers and beads) at lower concentrations on the freshwater
organism Ceriodaphnia dubia were evaluated. The acute (48 h) and chronic (192 h)
effects of PET fibers and PE bead microplastics on C. dubia were assessed alone and
as a binary mixture. The results showed a dose-dependent trend on survival, with C.
dubia more sensitive to PET fibers than PE microplastics. The 48 h EC50 value of
fibers was 1.5 mg/L compared to 2.2 mg/L for PE beads. The binary mixture of
microplastic beads and fibers demonstrated less than additive effects. EC50 values for
the chronic bioassay were 429 μg/L for fibers and 958 μg/L for PE microplastics. A
positive trend of decreasing growth (body size of adults) and reproduction rate
(number of neonates) with increasing microplastic concentration was observed for
both PE and fiber microplastics during the chronic bioassays. Using scanning
electron microscopy (SEM) we observed deformities, such as carapace and antenna
deformation, in C. dubia exposed to fibers at a high concentration, but not at the
lower (environmentally relevant) concentrations.
Given the likelihood that microplastics will eventually sink to the bottom sediment in
the aquatic ecosystem the effects of microplastics were investigated on a freshwater
sediment-dwelling organism (Chironomus tepperi) at environmentally relevant
concentrations of PE microplastics (500 particles/kgsediment). Possible size-dependent
effects of microplastics were also examined using four different size ranges of PE
beads including 1-4, 10-27, 43-54 and 100-126 μm. The results revealed that
exposure to an environmentally relevant concentration of microplastics had a
detrimental impact on the survival, growth (i.e., body length and head capsule) and
emergence of C. tepperi. The observed effects were strongly dependent on microplastic size with C. tepperi more sensitive to microplastics in the size range of
10-27 μm. No negative effects were observed on growth and survival of C. tepperi
exposed to the larger microplastics (100-126 μm), though a significant decrease in
the number of emerging adults was observed in the organisms exposed to the same
size range of microplastics. Further, SEM showed a significant reduction in the size
of the head capsule and antenna in C. tepperi exposed to microplastics in the size
range of 10-27 μm. These results showed that environmentally relevant
concentrations of microplastics in sediment can result in adverse effects on the
development and emergence of C. tepperi, with effects strongly dependent on
particle size.
Finally, we evaluated the effects of PE microplastics on the acute toxicity of a
pyrethroid insecticide (bifenthrin) to midge larvae (C. tepperi) in water. To test the
single and combined effects of bifenthrin and PE microplastics, C. tepperi larvae
were exposed to six concentrations of bifenthrin ranging from 0.1 to 3.2 μg/L in the
presence and absence of microplastics. To examine the possible effects of bifenthrin
and microplastics in synthetic and real water, the bioassays were performed in both
moderately hard water (MHW) and river water. We performed an uptake study using
three different size ranges of microplastics (10-27, 43-54, 100-126 μm) during 8-day
microplastics-spiked water exposure. The results showed that microplastics in the
size range of 10-27 μm were mostly ingested by C. tepperi larvae. Using this finding,
10-27 μm microplastics were selected for the bioassays. The results of the bioassays
using MHW demonstrated a significant decrease in the toxicity of bifenthrin in the
presence of microplastics. This is likely attributable to the tendency of bifenthrin to
bind to the microplastics, which reduces the bioavailability of bifenthrin to midge
larvae. However, in the bioassays conducted in river water with a total organic
carbon (TOC) concentration of 9.6 mg/L, no significant difference was observed
between the toxicity of bifenthrin to C. tepperi in the presence and absence of
microplastics. This is likely due to the interaction between organic carbon and
bifenthrin, which reduces the bioavailability of bifenthrin to C. tepperi larvae.
This thesis highlights that microplastic fibers and beads are released to the aquatic
environment from WWTPs, and that this can negatively affect survival, reproduction
and the life cycle of aquatic organisms (both pelagic and benthic) through
entanglement (fibers) and ingestion (beads). The effect of microplastics on chemical
contaminants is complex, and microplastics may act both as carriers but also as
“chelators” of chemicals in the water, thereby reducing their bioavailability.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Sc
Science, Environment, Engineering and Technology
Full Text
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Renner, Kofi Omare. "Particle size analysis, quantification and identification of microplastics in selected consumer products : a critical comparison of methods and analytical techniques". Thesis, Brunel University, 2018. http://bura.brunel.ac.uk/handle/2438/17133.
Texto completoResumen
Microplastics are particles that are < 5 mm in size and come from a wide range of sources. The global distribution in terrestrial and aquatic environments indicates they are likely to cause harm to living organisms. They are used in a variety of personal care products and kitchen scourers. To advance further studies, different approaches have been developed in recent years. In this research, a comparison of methods and analytical techniques were applied to characterise microplastics in two toothpastes and two facial scrubs. The analysis of microplastics was determined using light microscopy, laser diffraction, Fourier-transform infrared spectroscopy. This research reports for the first time, the application of Imaging flow cytometry to characterise microplastics, and was explored to characterise smaller sized particles in each product. The methods developed where validated by characterising particles abraded from kitchen scourers. Two market leading and three chain store brands of kitchen scourers were utilised for the characterisation of microplastics. The application of the different techniques indicated differences in the size, number and morphological characteristics of the particles analysed. The different approaches developed for particle extraction, and the analytical techniques had an apparent influence on the results produced. Currently, there are no universally accepted laboratory protocol and analytical techniques to characterise microplastics. However, this research can serve as a reference point to promote more studies on laboratory methods and analytical techniques to characterise microplastics, with the hope of understanding better these complex particles.
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Johansson, Emilia y Emma-Helena Ericsson. "Quantification for the Flow of Microplastic Particles in Urban Environment: A Case of the Chao Phraya River, Bangkok Thailand : A Minor Field Study". Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-230990.
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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.
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Giorgi, Valerio. "Analytical pyrolysis optimization for the quali-quantitative determination of polymer mixtures". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
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In recent years, the problem of "microplastics" has become increasingly worrying, as the amount of plastics that will be produced in the future will increase significantly. Microplastics are defined as emerging pollutants, due to the risks they may cause to the environment and especially to human health. The analytical issue behind their quantification in environmental matrices is quite complex. The thermoanalytical Py-GC/MS technique can provide qualitative and quantitative information about the microplastics more accurate than already applied optical techniques. The first aim of this thesis project was to determine the potentialities and limitations of such method for the quali-quantitative determination of polymers such as PET, PA6, PA66, PS, PP, PE and PVC. Particular attention was put on the interaction between polymers’ pyrolysis products. While this aspect has not been widely addressed in literature yet, it could result a limitation to the application of such technique for quantification purposes. Along this work pyrolytic interactions between PET with PA6, PA66 and PVC that lead to the formation of new compounds, were determined. These interferences were thought to be responsible in part for compromising the reproducibility of quantitative analyses.For this reason, polymers derivatisation tests were carried out with TMAH, an already widely used reagent for the analysis of microplastics. BSTFA and HMDS, other more innovative derivatisers in this field of research, were tested. TMAH proved to be very effective in eliminating interferences from a qualitative point of view. It also produced more satisfactory results for quantitative determination. However, the silylating reagents showed limitations in eliminating interactions. This precluded their use for possible quantification tests.
The results of this study provides the basis for the development of a robust thermoanalytical technique for microplastic quantification in environmental samples.
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von, der Esch Elisabeth [Verfasser], Martin [Akademischer Betreuer] Elsner, Jürgen [Gutachter] Geist, Martin [Gutachter] Elsner y Eric [Gutachter] Achterberg. "The automation and validation of a morphological and chemical quantification procedure for microplastic fragments using Raman microspectroscopy / Elisabeth von der Esch ; Gutachter: Jürgen Geist, Martin Elsner, Eric Achterberg ; Betreuer: Martin Elsner". München : Universitätsbibliothek der TU München, 2021. http://d-nb.info/1228073244/34.
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SCOPETANI, COSTANZA. "Microplastics in Freshwater and Marine Environments". Doctoral thesis, 2019. http://hdl.handle.net/2158/1152926.
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Fernandes, Mariana Ferreira. "Quantification of Macro and Microplastics on a Desert Island, Santa Luzia, Cabo Verde Archipelago, Norh East Atlantic Ocean". Master's thesis, 2019. https://hdl.handle.net/10216/121089.
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Botelho, Ana Lourenço. "Quantification and categorisation of microplastics in wild and aquaculture fish and in the water of the Aegean Sea". Master's thesis, 2021. http://hdl.handle.net/10400.26/38130.
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Plastic waste is recognised as a global threat to ecosystems. Microplastics may enter the food chain directly or indirectly in contaminated water or prey, respectively. Totally, 47 fishes from the inside and outside of aquaculture cages were analysed from Leros, a Greek island situated on the Aegean Sea. In addition, 11 samples of seawater were collected around aquaculture cages. The microplastics quantified were identified through a stereomicroscope and confirmed by a hot needle test. The results showed that in seawater and fish samples, fibres were the predominant type of microplastics, the main size was between 0.5 to 2 mm. Blue was the principal colour in fish and black was the principal colour in seawater samples. Furthermore, aquaculture and wild fishes are exposed to direct intake of microplastics from the seawater. This project demonstrates that the contamination and bioaccumulation of microplastics represent a real danger along the food chain.Os resíduos de plástico são reconhecidos como uma ameaça global para os ecossistemas. Os microplásticos podem entrar na cadeia alimentar direta ou indiretamente em água ou presa contaminada, respetivamente. No total, 47 peixes de dentro e fora das jaulas flutuantes de aquacultura foram analisados. Provenientes de Leros, uma ilha grega situada no Mar Egeu. Além disso, 11 amostras de água do mar foram recolhidas próximo das jaulas da aquacultura. Os microplásticos quantificados foram identificados através de um estereomicroscópio e confirmados pelo teste da agulha quente. Os resultados mostram que na água e nos peixes as fibras foram o tipo de microplásticos predominante, o tamanho principal foi de 0,5 a 2 mm. O azul foi a cor principal em peixes e o preto a cor principal nas amostras da água do mar. Adicionalmente, os peixes de aquacultura e selvagens estão expostos à ingestão directa de microplásticos da água do mar. Este projeto demonstra que a contaminação e bioacumulação de MPs representam um perigo real ao longo da cadeia alimentar.
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Fernandes, Mariana Ferreira. "Quantification of Macro and Microplastics on a Desert Island, Santa Luzia, Cabo Verde Archipelago, Norh East Atlantic Ocean". Dissertação, 2019. https://hdl.handle.net/10216/121089.
Texto completoCapítulos de libros sobre el tema "Microplastics quantification"
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Sangeetha, Dhanaraj, Ainala Shivani, Jogannagari Anusha, J. Ranjitha y Vani Narayanan. "A Critical Review on Separation, Identification, Quantification and Removal of Microplastics in Environmental Samples: Developments and Challenges". En Microplastics Pollution in Aquatic Media, 115–35. Singapore: Springer Singapore, 2022. http://dx.doi.org/10.1007/978-981-16-8440-1_6.
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Zhang, Haibo, Yufan Fei, Han Wang, Yiyang Chen, Shunyin Huang, Ben Yu, Jiaqing Wang et al. "Interaction of Microplastics and Organic Pollutants: Quantification, Environmental Fates, and Ecological Consequences". En The Handbook of Environmental Chemistry, 161–84. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/698_2020_451.
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Kumar, Rakesh y Prabhakar Sharma. "Recent Developments in Extraction, Identification, and Quantification of Microplastics from Agricultural Soil and Groundwater". En Fate and Transport of Subsurface Pollutants, 125–43. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-6564-9_7.
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Singh, Vicky y Sukalyan Chakraborty. "Quantification and Characterization of Microplastics in Kanke Lake, a Freshwater System of Ranchi, Jharkhand, India". En Lecture Notes in Civil Engineering, 271–81. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-15-9805-0_23.
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Kwach, Bowa O. y Victor Odhiambo Shikuku. "Microplastics as Emerging Contaminants". En Advances in Environmental Engineering and Green Technologies, 31–44. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-1871-7.ch003.
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The ever-increasing production of plastics and concomitant poor plastic waste disposal systems explain the recent rising concerns over the occurrence of microplastics in freshwater resources. Microplastics are presently recognized as emerging contaminants owing to the increasing reports on their occurrence in the environment and the associated toxicological effects. This chapter discusses the recent trends in the monitoring of microplastics in freshwater resources, the toxicological effects of microplastics, and the sampling and analysis techniques available for detection and quantification. The challenges in analysis and comparison of various studies and future prospects have also been highlighted.
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Renner, Gerrit, Torsten C. Schmidt y Jürgen Schram. "Characterization and Quantification of Microplastics by Infrared Spectroscopy". En Characterization and Analysis of Microplastics, 67–118. Elsevier, 2017. http://dx.doi.org/10.1016/bs.coac.2016.10.006.
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Mossotti, Raffaella, Giulia Dalla Fontana, Anastasia Anceschi, Enrico Gasparin y Tiziano Battistini. "Round Robin Test on Microplastic Counting and Identification Method". En Environmental Sciences. IntechOpen, 2023. http://dx.doi.org/10.5772/intechopen.109757.
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The aim of this work is to verify the quality, robustness, and accuracy of a standard analytical protocol for the determination of microplastics in aqueous textile matrices. In order to reach this objective, a round robin scale identification and quantification test program was conducted. In particular, this chapter describes the round robin test, an interlaboratory comparison test on standard microfilament suspensions initiated in November 2021 by an expression of interest open call. In total, 18 laboratories expressed their interest, and 13 participants sent their results. Each of these laboratories received a set of 10 samples, accompanied by a protocol. The 10 samples consisted of three replicates per type of three different synthetic yarns and a control sample. The data required were the number of microplastics per sample recognized as fibers or particles, microplastic fiber lengths and diameters, and identification of the polymer using vibrational spectroscopy (μ-FTIR and/or μ-Raman). The data collected were statistically elaborated. The results highlighted that the laboratories had different recovery rates directly related to their specific procedures and equipment. Although there were issues related to the correct use of the standard method and to the behavior of operators, the method proved to be valid for the determination of microplastics in aqueous matrices.
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Mossotti, Raffaella, Giulia Dalla Fontana, Anastasia Anceschi, Enrico Gasparin y Tiziano Battistini. "Preparation and Analysis of Standard Microplastics". En Environmental Sciences. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.108716.
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Over 14 million tons of microplastic have been accumulated in water resources and they are increasing yearly. About 8% of European microplastic released into the water are from synthetic textiles. This kind of microplastic is generally in the form of microfilaments. They have a higher potential to enter the food chain due to their size and shape. Although microfilaments generate great concern, no precise guidelines for their quantification and qualification are yet available. Thus, in this chapter, the origin of microfilaments is fully investigated. After that, a novel approach for identifying and counting microplastic with fiber shape is presented. An accurate method for preparing microfilament standard suspensions is described to facilitate lab tests and have a reliable methodology for monitoring microplastic pollution.
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Zehra, Alina, Kavita Krishna, Namrata Pandey y S. Anbumani. "Impacts of Microplastics on the Hydrosphere (Aquatic Environment)". En Advances in Human Services and Public Health, 226–48. IGI Global, 2022. http://dx.doi.org/10.4018/978-1-7998-9723-1.ch010.
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Pollution by microplastics is a recent global problem owing to their preponderance in various matrices like air, water, biota, sediment, or soil and has become a global concern for the future generation sustainability. The mushrooming concerns about the detrimental effects of microplastics (MPs) on biota in response to its crescive detection and quantification in the aqueous ecosystems is looming large since last few decades, and it's a need of the hour for a thorough ecological risk assessment. The chapter highlights the MP production, release, and transport pathways along with its detrimental impacts on the aquatic biota at different levels of biological organization with available degradation approaches.
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Hewawasam Udullege, Erangi Imasha y Sandhya Babel. "Microplastics Analytical Techniques in Water, Sediments, and Biota". En Advances in Human Services and Public Health, 306–27. IGI Global, 2022. http://dx.doi.org/10.4018/978-1-7998-9723-1.ch013.
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Identification and quantification of microplastics (MPs) pollution levels in all the environmental compartments including water, sediments, and biota are an hourly need. MPs analytical techniques in water, sediments, and biota consist of several laborious steps including sampling, sample handling, and analytical techniques for identification and quantification. Studies have employed a wide variety of techniques resulting in variation in MPs abundance and characteristics. MPs reporting techniques also vary between different studies. The sampling techniques, digestion reagents, the temperature applied, density separation reagents, and the techniques utilized cause significant impacts on the recovery rate of the MPs particles from samples. 20-10 μm has become the lower reliable, practical limit for MPs due to the limitations in identification methods. Since there is many more MPs research to be done, there is an urgency of establishing reliable and efficient standard methodologies for MPs monitoring enabling comparison of studies from different parts of the world.
Actas de conferencias sobre el tema "Microplastics quantification"
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Prosenc, Franja, Nigel Van de Velde, Ivan Jerman y Janez Langus. "Automated Quantification of Microplastics – Challenges and Opportunities". En Socratic Lectures 7. University of Lubljana Press, 2022. http://dx.doi.org/10.55295/psl.2022.d12.
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Plastics are an important material with widespread applications. However, their widespread use and poor end-of-life management have led to their extensive environmental pollution. They can be found in oceans, terrestrial ecosystems, and even remote corners of the Earth. Current methods for microplastic quantification and identification require big investments and highly trained personnel to operate the analytical equipment. In this paper, we propose an algorithm-based method for the quantification of microplastics in soil and organic fertilisers. The method is based on image analysis of a thinly spread sample that was heated until microplastics has visually melted. The algorithm-based method was validated with Focal plane array detector-based micro-Fourier-transform infrared imaging (FPA-μFTIR), frequently used in microplastic characterisation. Herein, we present the pre-liminary results of an ongoing study. In a compost sample, five particles were detected with FPA-μFTIR, whereas the algorithm detected eight. The algorithm has difficulties recognising elongated or oddly shaped particles. These were identified as several particles which led to overestimating the number of microplastic particles in the investigated sample. We will continue with further develop-ment of the computer algorithm by using a training set of images which will be quantified using different methods (visual detection by a human operator, FPA-μFTIR). This growing training set will enable us to incorporate machine learning algorithms (neural networks) in the development of a more reliable particle detection algorithm. We expect that environmental monitoring of microplas-tics will be required under future legislation, therefore the development of cheap, user-friendly so-lutions is crucial. Keywords: Machine learning; Algorithm; Infrared spectroscopy; Soil contamination; Organic ferti-lisers; Compost
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Bowman, Cole, Kelly Best Lazar, Stefanie Whitmire, Elizabeth Carraway y Gavin Gleasman. "SEDIMENT TRAP DEVELOPMENT AND QUANTIFICATION OF MICROPLASTICS DEPOSITION IN THE BLACK AND WACCAMAW RIVER SYSTEMS, SOUTH CAROLINA". En Joint 56th Annual North-Central/ 71st Annual Southeastern Section Meeting - 2022. Geological Society of America, 2022. http://dx.doi.org/10.1130/abs/2022nc-374913.
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Wegmayr, Viktor, Aytunc Sahin, Bjorn Samundsson y Joachim M. Buhmann. "Instance Segmentation for the Quantification of Microplastic Fiber Images". En 2020 IEEE Winter Conference on Applications of Computer Vision (WACV). IEEE, 2020. http://dx.doi.org/10.1109/wacv45572.2020.9093352.
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Primpke, Sebastian, Matthias Godejohann, Jeremy Rowlette y Gunnar Gerdts. "High-throughput environmental microplastic identification and quantification using a wide-field QCL-IR based microscope". En Optical Fibers and Sensors for Medical Diagnostics, Treatment and Environmental Applications XXI, editado por Israel Gannot y Katy Roodenko. SPIE, 2021. http://dx.doi.org/10.1117/12.2578414.
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Habib, Rana Zeeshan, Ruwaya Al Kendi y Thies Thiemann. "Quantification and characterization of microplastic originating in the emirate of Abu Dhabi, United Arab Emirates". En INDUSTRIAL, MECHANICAL AND ELECTRICAL ENGINEERING. AIP Publishing, 2022. http://dx.doi.org/10.1063/5.0122555.
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Sundar, Saketh. "A Novel Low-Cost Approach For Detection, Classification, and Quantification of Microplastic Pollution in Freshwater Ecosystems using IoT devices and Instance Segmentation". En 2022 IEEE MIT Undergraduate Research Technology Conference (URTC). IEEE, 2022. http://dx.doi.org/10.1109/urtc56832.2022.10002222.
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