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O objetivo desta pesquisa foi a identificação, por meio de espectroscopia no infravermelho com transformada de Fourier combinada com reflectância total atenuada (FTIR-ATR), de microplásticos extraídos do trato gastrointestinal de peixes coletados no Lago de Amatitlán, para determinar os principais polímeros e a possível origem da contaminação por esses materiais. Foram analisados 68 microplásticos, correspondendo a 10% do total de microplásticos extraídos. Estes originaram-se de 36 espécimes, sendo 35 da espécie Oreochromis niloticus e um de Parachromis managuensis, dos quais foram analisados de 1 a 5 microplásticos por espécime. Os polímeros identificados foram polipropileno (PP), nylon, polietileno de alta densidade (HDPE), tereftalato de polietileno (PET), látex, poliestireno (PE), polietileno de baixa densidade (LDPE) e poliuretano (PU). O polipropileno (32), o polietileno de alta densidade (13) e o nylon (10) foram os polímeros mais frequentes. Os possíveis itens plásticos que podem ter originado os microplásticos incluem brinquedos, equipamentos de laboratório, baldes, embalagens de alimentos, tubulações, isolamento para cabos, têxteis, cordas e móveis que são produzidos na indústria do plástico, localizada principalmente na vertente sul da cidade da Guatemala. Além disso, as espécies de peixes do presente estudo sustentam pescarias importantes, o que levanta problemas de saúde humana, uma vez que a ingestão de peixes que consomem plásticos tem o potencial de aumentar a carga corporal de substâncias químicas perigosas, pois estas aderem superficialmente aos plásticos no ambiente e são posteriormente bioacumuladas.
The objective of this research was the identification, through Fourier transform infrared spectroscopy combined with attenuated total reflectance (FTIR-ATR), of microplastics extracted from the gastrointestinal tract of fish collected in Lake Amatitlán, to determine the main polymers and the possible origin of contamination by these materials. 68 microplastics were analyzed, corresponding to 10% of the total microplastics extracted. These originated from 36 specimens, 35 of the species Oreochromis niloticus and one of Parachromis managuensis, of which 1 to 5 microplastics per specimen were analyzed. The polymers identified were polypropylene (PP), nylon, high-density polyethylene (HDPE), polyethylene terephthalate (PET), latex, polystyrene (PE), low-density polyethylene (LDPE) and polyurethane (PU). Polypropylene (32), high-density polyethylene (13) and nylon (10) were the most frequent polymers. Possible plastic items that may have caused microplastics include toys, laboratory equipment, buckets, food packaging, pipes, insulation for cables, textiles, ropes and furniture that are produced in the plastics industry, located mainly on the south side of Guatemala City. Furthermore, the fish species in the present study support important fisheries, which raises human health concerns, since the ingestion of fish that consume plastics has the potential to increase the body load of dangerous chemicals, as they adhere superficially to the plastics in the environment and are subsequently bioaccumulated.
ABSTRACT
Objective @#To investigate the effects of the exposure of sludge from sewage treatment plants and microplastic extracted from sludge on the oxidative stress levels in zebrafish, so as to put insights into the research into the impact of sludge and microplastics on human health. @*Methods @#Adult wild AB zebrafish were exposed to five groups of sludge (0, 12.5, 25, 50 and 75 g/L) and four groups of microplastics extract from sludge (0, 240, 480, 960/L), with 24 zebrafish in each group. The color, activity and death of zebrafish were observed every day. The contents of superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) and malondialdehyde (MDA) were detected 0 h, 24 h, 48 h, 72 h, 96 h and 7 d post-exposure. A two-factor ANOVA was used to analyze the effects of different concentrations and time of exposure on the indicators above. @*Results @#Under 75 g/L sludge exposure, zebrafish began to show mortality at 72 h and all died after 7 d. The zebrafish in the other sludge groups and all microplastic groups had normal color and activity, and no mortality was observed. Sludge concentration interacted with exposure time to affect SOD, CAT, GSH and MDA (P<0.05). With increasing sludge concentration and exposure time, SOD decreased, MDA increased, CAT increased first and then decreased, GSH decreased first and then increased, and GSH continued to decrease since 24 h in the 75 g/L group. The microplastic concentration interacted with exposure time to affect SOD and GSH (P<0.05), but not CAT or MDA (P>0.05). With increasing microplastic concentration and exposure time, SOD and MDA increased, CAT increased first and then decreased, the GSH was slightly increased at 24 h and decreased after 72 h.@*Conclusion @#Both sludge and microplastics extracted from sludge can induce oxidative stress damage in zebrafish, and exposure time and concentration can interact to affect oxidative stress levels. The microplastics extracted from sludge have less effect on oxidative stress levels in zebrafish than sludge.
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@#As a new type of environmental pollutants, microplastics are widely distributed in the global ecosystem, and ingestion of microplastics may produce a number of toxic effects. Based on currently available publications, this paper describes the main pathways of exposure to microplastics, and summarizes the toxic mechanisms of microplastics in mammals, including oxidative stress, inflammatory response, immune damage, imbalance of gut microbiota, energy metabolism disorder and DNA damage, so as to provide insights into elucidation of the toxic mechanism mechanisms and health risk assessment of microplastics.
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As a widespread pollutant in the environment, research on microplastics have attracted much attention. This review systematically analyzed the interaction between microplastics and soil microorganisms based on existing literatures. Microplastics can change the structure and diversity of soil microbial communities directly or indirectly. The magnitude of these effects depends on the type, dose and shape of microplastics. Meanwhile, soil microorganisms can adapt to the changes caused by microplastics through forming surface biofilm and selecting population. This review also summarized the biodegradation mechanism of microplastics, and explored the factors affecting this process. Microorganisms will firstly colonize the surface of microplastics, and then secrete a variety of extracellular enzymes to function at specific sites, converting polymers into lower polymers or monomers. Finally, the depolymerized small molecules enter the cell for further catabolism. The factors affecting this degradation process are not only the physical and chemical properties of the microplastics, such as molecular weight, density and crystallinity, but also some biological and abiotic factors that affect the growth and metabolism of related microorganisms and the enzymatic activities. Future studies should focus on the connection with the actual environment, and develop new technologies of microplastics biodegradation to solve the problem of microplastic pollution.
Subject(s)
Microplastics , Plastics , Soil , Polymers , Biodegradation, EnvironmentalABSTRACT
Microplastics pollution has attracted worldwide attention. Compared with the status quo of microplastics pollution in marine environment and other major rivers and lakes, the relevant data of the Yellow River basin is relatively inadequate. The abundance, types, and spatial distribution characteristics of microplastic pollution in the sediments and surface water of the Yellow River basin were reviewed. Meanwhile, the status of microplastic pollution in the national central city and Yellow River Delta wetland was discussed, and the corresponding prevention and control measures were put forward. The results showed that the spatial distribution of microplastics pollution in sediments and surface water of the Yellow River basin increased from upstream to downstream, especially in the Yellow River Delta wetland. There are obvious differences between the types of microplastics in sediment and surface water in the Yellow River basin, which is mainly related to the materials of microplastics. Compared with similar regions in China, the microplastics pollution levels in national key cities and national wetland parks in the Yellow River basin are in the medium to high degree, which should be taken seriously. Plastics exposure through various ways will cause serious impact on aquaculture and human health in the Yellow River beach area. To control microplastic pollution in the Yellow River basin, it is necessary to improve the relevant production standards, laws and regulations, and improve the capacity of biodegradable microplastics and the degradation capacity of plastic wastes.
Subject(s)
Humans , Microplastics , Plastics , Water Pollutants, Chemical/analysis , Environmental Monitoring/methods , Water , ChinaABSTRACT
Introducción: Los productos plásticos han transformado la era moderna de tal manera que la vida sin plásticos sería irreconocible, a la par de este desarrollo la contaminación plástica es omnipresente convirtiéndose en uno de los problemas ambientales modernos más importantes. Objetivo: Compilar la información publicada en los últimos cinco años sobre la contaminación ambiental por microplásticos en Ecuador para reforzar el interés local sobre estos contaminantes. Desarrollo: Se realizó una revisión no estructurada de la literatura. Se utilizaron como bases de datos PubMed y Google Scholar. Los criterios de inclusión fueron: artículos publicados en los últimos 5 años, en idiomas inglés y español, se excluyeron otros idiomas; la selección de estudios fue de tipo a conveniencia. Se organizó y analizó cronológicamente la evidencia publicada en PubMed y Google Scholar en los últimos 5 años sobre microplásticos en Ecuador. Consideraciones finales: La información recopilada muestra cronológicamente el avance de la contaminación por microplásticos tanto a nivel mundial como en Ecuador, además, se evidencia la presencia de microplásticos en océanos, agua dulce, ecosistemas terrestres, aire, alimentos y dentro del cuerpo humano. Por lo cual la contaminación por microplásticos es un tema de gran relevancia actual, que requiere acciones de control inmediatas.
Introduction: Commercial plastic products has transformed the modern era in such a way that current life without plastic would not be possible, so at the same time with this development, plastics contamination is present, becoming one of the most urgent environmental problems nowadays. Objective: To gather available information published on the last five years concerning the microplastics as a source of environmental contamination in Ecuador and in order to reinforce the local interest on plastic pollution. Development: An unstructured review of the literature was performed. Databases used, PubMed and Google Scholar. The inclusion criteria used were as follow: articles in English and Spanish published on the last 5 years, no other language; study selections have been done by convenience. It was chronologically organized and analyzed the evidence published in PubMed and Google Scholar on the last five years concerning the microplastics behavior in Ecuador. Final considerations: The information collected chronologically shows the advancing pollution caused by microplastics both globally and in Ecuador, in addition, the presence of microplastics in oceans, fresh water, terrestrial ecosystems, air, foods and even in the human body is evident. Therefore, contamination caused by microplastics is a topic of a great importance today, which requires a speedy control action.
Introdução: Os produtos plásticos transformaram a era moderna de tal forma que a vida sem plásticos seria irreconhecível, junto com esse desenvolvimento, a poluição plástica é onipresente, tornando-se um dos mais importantes problemas ambientais modernos. Objetivo: Compilar as informações publicadas nos últimos 5 anos sobre a contaminação ambiental por microplásticos no Equador para reforçar o interesse local por esses contaminantes. Desenvolvimento: Foi realizada uma revisão não estruturada da literatura. Foram utilizadas as bases de dados PubMed e Google Scholar. Os critérios de inclusão foram: artigos publicados nos últimos 5 anos, nos idiomas inglês e espanhol, foram excluídos outros idiomas; a seleção dos estudos foi do tipo conveniência. As evidências publicadas no PubMed e Google Scholar nos últimos 5 anos sobre microplásticos no Equador foram organizadas e analisadas cronologicamente. Considerações finais: As informações coletadas cronologicamente mostram o progresso da contaminação por microplásticos tanto no mundo quanto no Equador, além disso, é evidente a presença de microplásticos nos oceanos, água doce, ecossistemas terrestres, ar, alimentos e dentro do corpo humano. Portanto, a contaminação por microplásticos é um tema de grande relevância atual, que requer ações imediatas de controle.
ABSTRACT
With the extensive use of plastic products and the sharp increase of plastic waste, microplastics produced by degradation in the natural environment and artificially added by industry have been detected in food, air, ocean, and even extreme geographical environment. The environmental pollution and the biological health hazards caused by this new type of pollutant has become a global scientific problem to be solved urgently. Zebrafish (Danio rerio), as a typical model organism, has been widely used to evaluate the environmental pollution and health hazards caused by microplastics. This review on the research progress of model animal zebrafish in toxicity evaluation of microplastics mainly emphasized the toxic effects of microplastics on selected organs of zebrafish, briefly introduced the influencing factors of toxicity induced by microplastics, discussed the standardization of experiments for the evaluation of microplastic toxicity using zebrafish, and finally explored the future research directions.
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RESUMO O descarte inadequado de materiais plásticos, em razão de sua quantidade e características, tem ocasionado significativos impactos negativos aos ambientes aquáticos. Estudos sobre microplásticos, partículas de plástico menores do que 5 mm na sua dimensão maior, têm sido intensificados nos últimos anos. No entanto, ainda são incipientes os trabalhos com esse enfoque em sedimentos de água doce. Nesse sentido, o presente trabalho teve como objetivo testar a eficácia de diferentes metodologias de extração de microplásticos associados a sedimentos. Estudos experimentais foram desenvolvidos em laboratório, utilizando metodologias baseadas em diferença de densidade (adição de soluções saturadas de sacarose e de cloreto de sódio) e amostras de sedimentos secos. De uma maneira geral, o tratamento baseado na adição de solução saturada de sacarose apresentou maior eficiência de extração, quando comparado com os demais tratamentos. No tratamento no qual a amostra seca foi analisada, verificou-se maior dificuldade na separação e na identificação dos fragmentos plásticos, por estes apresentarem forma e/ou coloração similares às encontradas nas partículas do sedimento. Foi desenvolvida uma metodologia de baixo custo operacional, baixo impacto ambiental e de fácil aplicação, capaz de possibilitar o monitoramento de microplásticos presentes em sedimentos de água doce e, consequentemente, fornecer subsídios para tomadores de decisão, para a proposição de medidas de redução e controle da poluição por materiais plásticos.
ABSTRACT Inadequate disposal of plastic materials, due to their quantity and characteristics, has caused significant negative impacts on aquatic environments. Studies on microplastics, plastic particles smaller than 5 mm in their largest dimension, have been intensified in recent years. However, studies with this approach in freshwater sediments are still incipient. In this sense, the present research aimed at testing the effectiveness of the extraction of microplastics associated with sediments from freshwater environments. Experimental studies were carried out in laboratory, using methodologies based on density difference (addition of saturated solutions of sucrose and sodium chloride) and dry sediment samples. Overall, the treatment based on addition of saturated solution of sucrose presented a higher extraction efficiency when compared with the other treatments. In the treatment in which the dry sample was analyzed, there was greater difficulty in separating and identifying the plastic fragments due to the similarity of shape and/or color between the fragments and the sediment particles. A methodology of low operational cost, low environmental impact, and easy application was developed, capable of enabling the monitoring of microplastics present in freshwater sediments, and consequently providing subsidies for decision makers for proposing measures to reduce and control the pollution by plastic materials.
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Global plastics production has been increasing year by year. Due to the large quantity of plastics and the difficulty of their degradation, plastics are continuously accumulated in the environment. Therefore, plastic waste has become one of the most serious threats to the global environment. Microplastics can be absorbed into organisms through the mouth, respiratory tract and skin, causing organ(intestine, liver) toxicity, reproductive and developmental toxicity, and neurotoxicity. Moreover, microplastics can also take up other pollutants distributed in the surrounding environment, such as heavy metals and organic pollutants, jointly exerting combined toxic effects. The extracts of microplastics, including microplastics unstable polymers and additives, also have toxic effects. The molecular mechanisms involved in the toxic effects induced by microplastics include oxidative stress, inflammation, disturbance of intestinal flora, disturbance of gene expression, and others.
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Microplastics refer to plastic fibers, particles, or films with a particle size less than 5 mm, and microplastics pollution has become one of the major global environmental problems. Microplastics can be exposed to the human body through ingestion, inhalation and skin contact, affecting maternal and fetal health through mechanisms such as cytotoxicity and signal transduction, energy homeostasis and metabolic disorders, immune dysfunction, and as carriers of microorganisms or toxic chemicals. The purpose of this paper is to review the physical and chemical properties of microplastics, human exposure pathways, maternal-fetal effects, and its mechanisms.
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Microplastics refer to plastic particles with a diameter of less than 5 mm. Because of their wide distribution in the environment, it has gradually become one of the environmental hot issues of global concern in recent years. Microplastics are characterized by small particle size and strong adsorption. Existing studies have confirmed the biotoxic effects of microplastics in marine organisms and in experimental animals, suggesting their potential harm to human health. However, there have been few studies on the effects of microplastics on human health, and the research results have been inconsistent. Therefore, by summarizing the recent domestic and foreign studies about human exposure to microplastics as well as their potential effects on human body, this paper provides ideas and theoretical basis for further exploring the effects of microplastics on human health and related mechanisms.
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Plastics are extensively used in our daily life. However, a significant amount of plastic waste is discharged to the environment directly or via improper reuse or recycling. Degradation of plastic waste generates micro- or nano-sized plastic particles that are defined as micro- or nanoplastics (MNPs). Microplastics (MPs) are plastic particles with a diameter less than 5 mm, while nanoplastics (NPs) range in diameter from 1 to 100 or 1000 nm. In the current review, we first briefly summarized the environmental contamination of MNPs and then discussed their health impacts based on existing MNP research. Our review indicates that MNPs can be detected in both marine and terrestrial ecosystems worldwide and be ingested and accumulated by animals along the food chain. Evidence has suggested the harmful health impacts of MNPs on marine and freshwater animals. Recent studies found MPs in human stool samples, suggesting that humans are exposed to MPs through food and/or drinking water. However, the effect of MNPs on human health is scarcely researched. In addition to the MNPs themselves, these tiny plastic particles can release plastic additives and/or adsorb other environmental chemicals, many of which have been shown to exhibit endocrine disrupting and other toxic effects. In summary, we conclude that more studies are necessary to provide a comprehensive understanding of MNP pollution hazards and also provide a basis for the subsequent pollution management and control.