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1.
Bioresour Technol ; 326: 124777, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33540214

RESUMEN

To investigate the effect of microplastics (MPs) particles in vermicomposting, polyethylene (PE) particles added into sludge. Results showed that the vermicomposting with high MPs addition obtained lower removal efficiencies for organics than the vermicomposting with low MPs addition. The content of DOC and NH4+-N in M4 reactor (with the highest MPs addition) at 80 days was 8.4 mg/kg and 74.2 mg/kg, respectively. The pH, C/N, electrical conductivity (EC), and germination index (GI) results showed that the addition amount of MPs was directly proportional to the negative effect of composting. The negative effect mainly occurred after 20 days of composting. High MPs addition resulted in apparent oxidative stress and neurotoxicity on earthworm, the values of catalase (CAT) and acetylcholine esterase (AChE) in M4 reactor increased by 2.03 times and 1.60 times. The bacteria in M4 were more barren and lower in terms of diversity.


Asunto(s)
Compostaje , Oligoquetos , Animales , Microplásticos , Plásticos , Aguas del Alcantarillado , Suelo
2.
Water Sci Technol ; 83(3): 532-542, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33600359

RESUMEN

The tremendous increase of plastic production, its intensive usage in packaging, as transport material, and the insufficient management of plastic garbage have led to a rise in microplastic particles as an anthropogenic contaminant in our environment. To develop appropriate management and remediation strategies for this global pollution problem, reliable and consistent analytical procedures for measuring plastics in the complex matrices need to be designed. The applicability of an easy, robust and fast multi-step approach was tested on three sediment samples from riverine, beach and backwater areas of varying origin, grain size and organic matter content, and is reported here. The optimized method included grain size fractionation, density separation and µ-FTIR analyses. Identification was based on two complementary methods of µ -FTIR measurements, the Image mode for small microplastics (<1 mm) and the ATR method for bigger (1-5 mm) particles. The analyses revealed the identification of several polymers in various grain sizes at different pollution levels. Major findings are the dominance of PET particles and the highest frequency of microplastic particles in the midsize fraction of 100-500 µm. Generally, the method was able to reliably detect microplastic particles in several grain size fractions and down to very low contamination levels of approximately. ten particles per 50 g of sediments with different organic matter content and various grain size characteristics. Moreover, the presented multi-step approach represents a fast, easy and less cost-effective method as an alternative to more expensive and time-consuming methods.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Contaminación Ambiental , Sedimentos Geológicos , Plásticos , Contaminantes Químicos del Agua/análisis
3.
Mar Pollut Bull ; 163: 111960, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33453512

RESUMEN

Although India is one of the major plastic-waste-generating countries, few studies have been conducted on microplastics (MPs) in freshwater systems that are key contributors to oceans. The current study explores MPs in sediments and water that were collected at five major cities across the Ganga River. MPs number and mass density range in sediment were found to be 17 to 36 items/kg dry weight (d.w.) and 10 to 45 mg/kg d.w. of sediments, respectively, while in the water sample, they were 380 to 684 items/1000 m3 and 143 to 340 mg/1000 m3, respectively. Overall, white color and film-shaped MPs were the major contributors in all samples. MPs of 2.5-5 mm size contributed to a greater number and mass as compared to other fractions. Polyethylene was found to be a widely distributed plastic-type reflecting its high usability.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Ciudades , Monitoreo del Ambiente , Agua Dulce , Sedimentos Geológicos , India , Océanos y Mares , Plásticos , Ríos , Agua , Contaminantes Químicos del Agua/análisis
4.
Mar Pollut Bull ; 163: 112012, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33454637

RESUMEN

An investigation of microplastic abundance and its characteristics was conducted in Muara Angke Wildlife Reserve, a relic mangrove forest in the Jakarta metropolitan, to contribute to marine microplastics' national data inventory. Microplastics were found in all the stations, with an average of 28.09 ± 10.28 particles per kg of dry sediment (n kg-1). Sediments in the outside mangrove area contained more microplastics than the inside area. Foam form was the most dominant in all the samples and was found more abundant on the outside. More than half of microplastics were of size <1000 µm, and nearly 50% were polystyrenes. This polymer is widely used for food packaging, which is prone to be fragmented. Polypropylene and polyethylene form another 50% of microplastics, which are widely used for textiles and fishing gears. As Jakarta is the largest city in Indonesia, this microplastic dataset may be the benchmark for other mangroves around the country.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Animales , Animales Salvajes , Monitoreo del Ambiente , Sedimentos Geológicos , Indonesia , Plásticos , Contaminantes Químicos del Agua/análisis
5.
Mar Pollut Bull ; 163: 111986, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33461078

RESUMEN

Small-sized plastic debris (micro- and mesoplastics) are emerging pollutants and widely detected in aquatic environments. However, micro- and mesoplastics pollution research with regard to landfills is limited. In this study, the occurrence, characteristics, and possible release of micro- and mesoplastic waste from the Galuga landfill leachate to the aquatic environment were studied. Micro- and mesoplastics were identified in all surface water samples from leachate influent and effluent of Galuga landfills. The average daily release to the aquatic environment was estimated at 80,640 ± 604.80 microplastic and 618,240 ± 1905.45 mesoplastic particles, respectively. The amount of microplastic increased three-fold and nine-fold for mesoplastics after input from the leachate drain. Micro- and mesoplastic main chemical compositions were polyethylene, polypropylene, polystyrene, polyethylene terephthalate, polyester, and cellophane. This study implied that the leachate may cause micro and mesoplastic contamination to the aquatic environment. The results raised the knowledge of small-sized plastic debris in aquatic environments.


Asunto(s)
Eliminación de Residuos , Contaminantes Químicos del Agua , Indonesia , Microplásticos , Plásticos , Residuos Sólidos/análisis , Instalaciones de Eliminación de Residuos , Contaminantes Químicos del Agua/análisis
6.
Water Res ; 192: 116853, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33513468

RESUMEN

Microplastics pollution in aquatic ecosystems is of great concern; however, systemic investigations are still lacking in freshwater wetland systems used for wastewater treatment. The present study discusses such freshwater wetland system in Eastern India to understand its microplastics transport mechanism, heavy metals association and microplastics removal efficiency. Microplastics (63 µm - 5 mm) were heavily found in surface water and sediments of treatment ponds (7.87 to 20.39 items/L and 2124.84 to 6886.76 items/kg) and associated wastewater canals (30.46 to 137.72 items/L and 1108.78 to 34612.87 items/kg). A high content of toxic metals (As, Cd, Cr, Cu, Ni, Pb and Zn) were found on the microplastics with polyethylene terephthalate and polyethylene as major plastics types which were also found in fishes and macroinvertebrates of treatment ponds. Machine learning algorithm revealed a close association between microplastics content in fishes and surface water, indicating risk associated with floating microplastics to the aquatic biota. The study also revealed that microplastics were acting as heavy metals vector and potentially causing fish contamination. Surface water microplastics removing efficiency of the treatment ponds was estimated to be 53%. The study bespeaks about transport of microplastics through wastewater canals and their retention in treatment ponds emphasizing sustainability maintenance of natural wastewater treatment systems especially considering microplastics contamination to the aquatic biota of freshwater wetland systems.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Purificación del Agua , Animales , Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos , India , Metales Pesados/análisis , Microplásticos , Plásticos , Contaminantes Químicos del Agua/análisis , Humedales
7.
Water Res ; 192: 116852, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33517045

RESUMEN

Plastic pollution in aquatic environments, particularly microplastics (<5 mm), is an emerging health threat. The buoyancy, hydrophobic hard surfaces, novel polymer carbon sources and long-distance transport make microplastics a unique substrate for biofilms, potentially harbouring pathogens and enabling antimicrobial resistance (AMR) gene exchange. Microplastic concentrations, their polymer types and the associated microbial communities were determined in paired, contemporaneous samples from the Dutch portion of the river Rhine. Microplastics were collected through a cascade of 500/100/10 µm sieves; filtrates and surface water were also analysed. Microplastics were characterized with infrared spectroscopy. Microbial communities and selected virulence and AMR genes were determined with 16S rRNA-sequencing and qPCR. Average microplastic concentration was 213,147 particles/m3; polyamide and polyvinylchloride were the most abundant polymers. Microbial composition on 100-500 µm samples differed significantly from surface water and 10-100 µm or smaller samples, with lower microbial diversity compared to surface water. An increasingly 'water-like' microbial community was observed as particles became smaller. Associations amongst specific microbial taxa, polymer types and particle sizes, as well as seasonal and methodological effects, were also observed. Known biofilm-forming and plastic-degrading taxa (e.g. Pseudomonas) and taxa harbouring potential pathogens (Pseudomonas, Acinetobacter, Arcobacter) were enriched in certain sample types, and other risk-conferring signatures like the sul1 and erm(B) AMR genes were almost ubiquitous. Results were generally compatible with the existence of taxon-selecting mechanisms and reduced microbial diversity in the biofilms of plastic substrates, varying over seasons, polymer types and particle sizes. This study provided updated field data and insights on microplastic pollution in a major riverine environment.


Asunto(s)
Microbiota , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Microplásticos , Países Bajos , Plásticos , ARN Ribosómico 16S/genética , Contaminantes Químicos del Agua/análisis
8.
Sci Total Environ ; 766: 144249, 2021 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-33421781

RESUMEN

Nanoplastics are a growing environmental and public health concern. However, the toxic mechanisms of nanoplastics are poorly understood. Here, we evaluated the effects of spherical polystyrene nanoplastics on reproduction of Daphnia pulex and analyzed the proteome of whole animals followed by molecular and biochemical analyses for the development of an adverse outcome pathway (AOP) for these contaminants of emerging concern. Animals were exposed to polystyrene nanoplastics (0, 0.1, 0.5, 1 and 2 mg/L) via water for 21 days. Nanoplastics negatively impacted cumulative offspring production. A total of 327 differentially expressed proteins (DEPs) were identified in response to nanoplastics which were further validated from gene expression and enzyme activity data. Based on these results, we propose an AOP for nanoplastics, including radical oxygen species production and oxidative stress as the molecular initiating event (MIE); followed by changes in specific signaling pathways (Jak-STAT, mTOR and FoxO) and in the metabolism of glutathione, protein, lipids, and molting proteins; with an end result of growth inhibition and decrease reproductive output. This study serves as a foundation for the development of a mechanistic understanding of nanoplastic toxicity in crustaceans and perhaps other aquatic organisms.


Asunto(s)
Rutas de Resultados Adversos , Contaminantes Químicos del Agua , Animales , Daphnia , Microplásticos , Poliestirenos , Proteómica , Contaminantes Químicos del Agua/toxicidad
9.
Environ Sci Pollut Res Int ; 28(8): 8953-8967, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33447976

RESUMEN

Microplastics have caused considerable harm to the environment and threatened human health due to their strong adsorption and hard biodegradation. Therefore, the research of microplastic received increasing attention recently, producing numbers of related achievements. To comprehensively grasp the quantitative information of published papers on "microplastics," we analyzed the research progress and hotspots of "microplastics" through visualization software "VOSviewer." The results show that the number of literature on microplastics published from 2009 to 2019 increased exponentially (R2 = 0.9873). The top 10 cited references are mainly in "zooplankton ingesting microplastics," "microplastics in artificially cultivated bivalve," "microplastics in surface waters such as lakes," etc. The cutting-edge microplastics research is adsorption, biodegradation, ingestion and accumulation model, and toxicity analysis. In addition, the results predict that the combination of constructed wetland, biotechnology, and photocatalysis to remove microplastics will become new hotspots. The study provides researchers in microplastics with an overview of existing research and directional guidance for future research.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Animales , Bibliometría , Monitoreo del Ambiente , Humanos , Plásticos , Contaminantes Químicos del Agua/análisis
10.
Environ Pollut ; 271: 116363, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33385895

RESUMEN

The concern about microplastic (a group of polymers) in the environment may cause us to overlook a more substantial problem: microplastics will fragment into nanoplastics. This fragmentation will lead to a high number of nanoplastics particles. Such nanoplastic can be taken up by cells, as opposed to microscale particles that are either not or to much less extend taken up. Fragmentation into nano will also release materials previously safely embedded in the polymer. We here present results from 25 OECD/ISO in vivo hazard tests, and beyond, e.g. extended exposure duration, with Enchytraeus crypticus, using pristine nano-scale materials (NMs) [CuO, Fe2O3, Organic Pigment, MWCNT], fragmented products (polymers) with these NMs embedded in the matrices (FP_NM), and fragmented polymers without NMs (FP) [covering the 4 major plastic types: Acrylic, Polyethylene, Polypropylene and Epoxy]. For example, MWCNTs induced a highly significant population decrease after extended period of 60 days, despite having no impact after 28 days' exposure, the standard OECD duration. We conclude, that the standard tests were not suitable to evaluate hazards of these plastic fragments, weathering/ageing of materials is recommended, and extension of test duration can add value to the testing of NMs. We must refocus the concern to testing with polymers (not only "plastics"), from micro-to nano-polymers, and from aquatic to terrestrial environments.


Asunto(s)
Oligoquetos , Contaminantes Químicos del Agua , Animales , Contaminación Ambiental , Microplásticos , Plásticos , Polímeros , Contaminantes Químicos del Agua/análisis
11.
Water Res ; 191: 116785, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33401167

RESUMEN

Microplastic pathways in the environment must be better understood to help select appropriate mitigation strategies. In this 2-year long field study, microplastics were characterized and quantified in urban stormwater runoff and through a bioretention cell, a type of low impact development infrastructure. Concentrations of microparticles ranged from below the detection limit to 704 microparticles/L and the dominant morphology found were fibers. High rainfall intensity and longer antecedent dry days resulted in larger microparticle concentrations. In addition, atmospheric deposition was a source of microplastics to urban runoff. Overall, these results demonstrate that urban stormwater runoff is a concentrated source of microplastics whose concentrations depend on specific climate variables. The bioretention cell showed an 84% decrease in median microparticle concentration in the 106-5,000 µm range, and thus is effective in filtering out microplastics and preventing their spread to downstream environments. Altogether, these results highlight the large contribution of urban stormwater runoff to microplastic contamination in larger aquatic systems and demonstrate the potential for current infiltration-based low impact development practices to limit the spread of microplastic contamination downstream.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Plásticos , Lluvia , Movimientos del Agua , Contaminantes Químicos del Agua/análisis
12.
Water Res ; 191: 116797, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33422976

RESUMEN

In this study, a new photo-irradiated reductive dechlorination pathway and the underlying transformation mechanism are described for poly(vinyl chloride) microplastics (PVC-MPs). PVC-MPs underwent photo-reductive dechlorination process with the release of chloride ions. This reaction could be facilitated in the presence of indole-3-acetic acid (IAA) and hexadecyltrimethylammonium bromide (CTAB) under neutral pH and simulated sunlight irradiation conditions. Electrostatic interaction between IAA and CTAB produced neutral IAA/CTAB complex, which might account for the enhanced adsorption of IAA on PVC powders. Upon photo-irradiation, the adsorbed IAA was excited to generate hydrated electrons (eaq-), which could pass through a shorter distance to PVC-MP surface than that derived from homogeneous IAA molecules in aqueous solution. Transient spectra of laser flash photolysis provided direct evidence for the generation of eaq-, which supported the proposed dechlorination mechanism. Based on the results of attenuated total reflectance/Fourier transform infrared (ATR/FTIR) and Raman spectra, C-Cl bond cleavage and polyene formation were involved in the structural transformation of PVC-MPs. Due to the hydrophobic effects and π-π interactions between aromatic rings and polyene structures in PVC-MP surface, the PVC-MP powders irradiated in the presence of IAA/CTAB showed an enhanced sorption for both hydrophobic and hydrophilic aromatic chemicals.


Asunto(s)
Microplásticos , Cloruro de Vinilo , Electrones , Ácidos Indolacéticos , Plásticos , Cloruro de Polivinilo , Tensoactivos
13.
Mar Pollut Bull ; 163: 111948, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33482492

RESUMEN

An investigation into the abundance and distribution of meso- and microplastics within the Port of Durban was conducted using a static immersible water pump and particle filtration system to collect meso- and microplastics from the water column, microplastics from sediment samples and corresponding CTD. Microplastics were detected in all samples under investigation. Results suggest that sewage overflow, stormwater drains, port operations, followed by rivers are input areas for mitigation to focus on. Identifying meso- and microplastics inputs, baselines and distribution allow for long term monitoring and management in a harbour environment. This can potentially contribute to the control and regulation of small plastics particles in harbours, and the subsequent transport of these pollutants via dredged material into other ecosystems.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Ecosistema , Monitoreo del Ambiente , Plásticos , Sudáfrica , Contaminantes Químicos del Agua/análisis
14.
Mar Pollut Bull ; 163: 111972, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33482493

RESUMEN

Microplastics as emerging environmental pollutants, its effect to the bioprocess of water and wastewater treatment has aroused concern. This study investigated the effects of microplastic polystyrene (PS) particle size to the activated sludge nutrient removal process. The ammonia, nitrite, nitrate and phosphorus removal under various PS particle size during nitrification and denitrification process was tested. The results indicated that with PS particle size 150-300 µm, the ammonia oxidation during nitrification process was inhibited to 71%, 92%, and 80% as compared with the blank reactor, for PS concentration at 0.01 g/L, 0.05 g/L and 0.10 g/L, respectively. The nitrite accumulation during nitrification process was also high at PS particle size 150-300 µm and concentration no less than 0.05 g/L. The nitrate reduction during the denitrification process was all inhibited to 69%-94% as compared with the blank, except for reactor No.4. The phosphate removal during nitrification process was not affected by the existence of microplastics PS, the average removal rate was over 80% after 2 h and over 95% after 3 h, respectively. The microplastics particle size plays important role in affecting the activated sludge nutrient removal process.


Asunto(s)
Microplásticos , Aguas del Alcantarillado , Reactores Biológicos , Desnitrificación , Nitrificación , Nitrógeno , Nutrientes , Tamaño de la Partícula , Plásticos , Eliminación de Residuos Líquidos
15.
Mar Pollut Bull ; 163: 111979, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33484990

RESUMEN

In 2010, Indonesia estimated as the second-largest country in the world that donates plastic to the sea. This study aims to investigate the spatial and temporal distribution of microplastics in tropical estuaries. The sampling was carried out in Benoa Bay with four repetitions representing the wet and dry seasons. Spatially it was found that the highest microplastic abundance around the Suwung landfill, while the lowest at Badung River Estuary, middle, and an inlet of the Benoa Bay. The highest percentage to the lowest microplastic based on the size was 500-1000 µm (37.9%), >1000 µm (35.7%), 300-500 µm (22.1%), and <300 µm (4.3%), while based on the shape were fragments (73.19%), foam (17.02%), fiber (6.38%), and granule (3.40%). No significant differences were found between the wet and dry seasons based on the abundance, but significantly varied based on size and shape. Polymers of microplastics were dominated by polystyrene, polypropylene, and polyethylene.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Bahías , Monitoreo del Ambiente , Estuarios , Indonesia , Plásticos , Agua , Contaminantes Químicos del Agua/análisis
16.
Mar Pollut Bull ; 163: 111973, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33484991

RESUMEN

The growing use of plastic and their indiscriminate disposal into the environment has resulted in the accumulation of huge quantities of microplastic (MP) in the marine environment. Several studies have investigated the pathways of MPs reaching marine environments and a few have begun looking at their inventories in sediment profiles. Recent estimates suggest between 70 and 90% of the MP particles are accumulated into sediment profiles. This paper reviews MPs in sediment cores, and the methods used for chronological reconstruction to provide evidence to link the plastic usage and MP inventories over time. In one example, a 210Pb dated sediment core from Kuwait Bay revealed 0.1 MPs g-1 of sediment deposited in approximately 1951 and 0.5 MPs g-1 in sediment from 2009 indicating a progressively increasing presence in recent sediments. The review also highlights the issue of very large spatio-temporal variation in MP concentrations, indicating the limitation of a snapshot study especially when dealing with the surface sediments; and it demonstrates the relevance of using sediment cores for a better assessment of MP input and inventories in the marine environment. It is proposed that MP sediment data should be reported as N m-2 year-1 or g m-2 year-1, and cores preferably dated using 210Pb, and supported by at least one other stratigraphic marker to enhance the usefulness of these datasets, since 210Pb can reliably date sediments as old as 100 years, a time-span which extends well beyond the time plastic production began. The anomalies in data processing and reporting in terms of number per kg of sediment or per cm2/m2 should be addressed essentially by adopting a standardized protocol.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Sedimentos Geológicos , Kuwait , Plásticos , Contaminantes Químicos del Agua/análisis
17.
Mar Pollut Bull ; 163: 111969, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33515857

RESUMEN

Abundance, chemical composition and ecological risk of microplastics (MPs) in terrestrial and marine environments have merited substantial attention from the research communities. This is the first attempt to comprehend the ecological risk of MPs in sediments along the Indian coast using meta-data. Polymer hazard index (PHI), pollution load index (PLI) and potential ecological risk index (PERI) were used to evaluate the quality of sediments. Areas have high PHI values (>1000) due to the presence of polymers with high hazard scores such as polyamide (PA) and polystyrene (PS). According to PLI values, sediments along the west coast of India (WCI) are moderately contaminated with MPs (PLI: 3.03 to 15.5), whereas sediments along the east coast of India (ECI) are less contaminated (PLI: 1 to 6.14). The PERI values of sediments along the Indian coast showed higher ecological risk for the metropolitan cities, river mouths, potential fishing zones and the remote islands.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Ciudades , Monitoreo del Ambiente , Sedimentos Geológicos , India , Plásticos , Medición de Riesgo , Contaminantes Químicos del Agua/análisis
18.
Ecotoxicol Environ Saf ; 211: 111899, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33453641

RESUMEN

The presence of microplastics and arsenic in soil can endanger crop growth; therefore, their effects on the properties of rhizosphere soil should be evaluated. Large (10-100 µm) and small (0.1-1 µm) polystyrene (PSMP) and polytetrafluorethylene (PTFE) particles were added to soil with different arsenic concentrations (1.4, 24.7, and 86.3 mg kg-1) to investigate the combined effect of microplastics and arsenic pollution on rice rhizosphere soil. After the addition of PSMP and PTFE, pH, arsenic (V) and arsenic (III) in the soil were observed to decrease. The interaction of arsenic with PSMP and PTFE resulted in this phenomenon, leading to a decrease of arsenic bioavailability in the soil. PSMP, PTFE, and arsenic reduced the abundance of Proteobacteria, increased the abundance of Chloroflexi and Acidobacteria, and inhibited soil urease, acid phosphatase, protease, dehydrogenase, and peroxidase activity via affecting the tertiary structure of the enzyme. PSMP, PTFE, and arsenic also reduced the available nitrogen and phosphorus content in the soil. Arsenic increased the soil organic matter content, whereas PSMP and PTFE reduced the organic matter content. Furthermore, microplastics inhibited the effects of arsenic on the microbial and chemical properties of the rhizosphere soil. This study revealed the effects of microplastic and arsenic pollution on rice rhizosphere microorganisms and nutrients, and elucidated the mechanism by which these pollutants retard crop growth in the designed growth medium.


Asunto(s)
Arsénico/toxicidad , Microplásticos/toxicidad , Contaminantes del Suelo/toxicidad , Arsénico/análisis , Contaminación Ambiental , Nitrógeno , Nutrientes , Oryza/crecimiento & desarrollo , Plásticos , Rizosfera , Suelo/química , Microbiología del Suelo , Contaminantes del Suelo/análisis
19.
Mar Pollut Bull ; 163: 111956, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33385798

RESUMEN

This study aimed to provide the first description of the presence, quantity, and diversity of microplastics (MPs) in intertidal sediments from the world's longest natural beach, Cox's Bazar. MPs were extracted from 24 surficial sediment samples through the density separation method, and identification was carried out using a stereomicroscope. Results showed that the abundance of MPs varied from 200 to 378.8 items kg-1 with the mean abundance of 368.68 ± 10.65 items kg-1. Fibers were the dominant (53%) MPs in this study, followed by films (20%) and fragments (12%). The dominant plastic particle color was purple (18%), followed by pink (14%) and red (7%), with shapes that were mainly filamentous (53%) and irregular (41%). The majority (59%) of the MPs measured were 1-5 mm in size, followed by 0.5-1 mm (27%) and <0.5 mm (14%).


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Bangladesh , Monitoreo del Ambiente , Sedimentos Geológicos , Plásticos , Contaminantes Químicos del Agua/análisis
20.
Mar Pollut Bull ; 163: 111879, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33385799

RESUMEN

Since the COVID-19 outbreak was declared as a global health emergency, the use of multiple types of plastic-based PPEs as a measure to reduce the infection increased tremendously. Recent evidence suggests that the overuse of PPEs during the COVID-19 pandemic is worsening plastic pollution in the marine environment. In this short focus, we discussed the potential sources, fate, and effects of PPE plastic to the marine environment and proposed five key research needs, involving (1) the occurrence and abundance of PPEs, (2) the sources, fate, and drivers of PPEs, (3) PPEs as a source of microplastics, (4) PPEs as a vector of invasive species and pathogens, and (5) PPEs as a source and vector of chemical pollutants in the marine environment. We suggest that addressing these knowledge gaps will lay the groundwork for improved COVID-19-associated waste management and legislation to prevent marine plastic pollution to continue exacerbating.


Asunto(s)
Plásticos , Humanos , Microplásticos , Pandemias
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