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1.
Environ Res ; 197: 111141, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33844971

RESUMEN

Microplastics have been predominantly studied in marine environments compared to freshwater systems. However, the number of studies analyzing microplastic concentrations in water and sediment within lakes and rivers are increasing and are of utmost importance as freshwaters are major pathways for plastics to the oceans. To allow for an adequate risk assessment, detailed knowledge concerning plastic concentrations in different environmental compartments of freshwaters are necessary. Therefore, the major aim of this study was the quantification and analysis of temporal and spatial distribution of microplastics (<5 mm) in freshwater shore and bed sediments at Lake Tollense, Mecklenburg-Western Pomerania, Germany. Likewise, it addresses the hypothesis that lakes may serve as long-term storage basins for microplastics. Concentrations were investigated semi-annually over a two-year period at four sandy bank border segments representing different expositions and levels of anthropogenic influence. In addition, lakebed samples were taken along the longitudinal dimension of Lake Tollense. Mean microplastic abundances were 1,410 ± 822 particles/kg DW for lakeshore sediments and 10,476 ± 4,290 particles/kg DW for lakebed sediments. Fragments were more abundant compared to fibers in both sediment compartments. Spatial and temporal variation was especially recognized for lakeshore sediments whereas microplastic abundances in lakebed sediments did not differ significantly between sampling points and sampling campaigns. This can be related to long-term accumulation at the lakebed. Lower microplastic abundances were found within the intertidal zone at lake beaches where constant wave action reduces accumulation. Increased microplastic abundances were recognized at the beach with least anthropogenic influence but in proximity to a tributary, which may serve as microplastic input pathway into Lake Tollense due to its catchment comprising mainly agricultural areas. Furthermore, spatial variations in microplastic concentrations were related to the abundance of macroplastic items at beaches and correlated with pedologic sediment characteristics, namely the content of organic matter.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Sedimentos Geológicos , Alemania , Lagos , Plásticos , Contaminantes Químicos del Agua/análisis
2.
Environ Sci Pollut Res Int ; 29(8): 11345-11358, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34533749

RESUMEN

The widespread presence of microplastics in multiple environmental compartments has largely been demonstrated. Assessing the ecological risk that microplastics pose is, at the present stage, hindered due to methodical differences. Moreover, different methods hamper meaningful comparisons between studies and data on microplastics <300 µm is scarce. Therefore, we focused on microplastics >20 µm in freshwater and sampling-related aspects in this concern. Sampling was conducted between 2018 and 2020 in the Tollense catchment in northeastern Germany and was carried out by in situ pump filtration. Two different sampling systems (cutoff sizes 20 µm and 63 µm) were applied to filter water volumes of 0.075-1.836 m3. Retained particles were analyzed by a combination of Nile red staining and micro-Raman spectroscopy. Thereby, we found microplastic concentrations between 123 and 1728 particles m-3 using the 63-µm cut-off size and between 1357 and 2146 particles m-3 using the 20-µm cut-off size. Local hydrodynamics (discharge and flow velocity) and land cover are likely influencing the observed microplastic concentrations and fluxes. The variability between both sampling systems cannot fully be explained by the different mesh sizes used. We argue that differentiation between a theoretical cut-off size (finest mesh) and a factual cut-off size (reliable quantification) can help to understand sampling related differences between studies.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Plásticos , Agua , Contaminantes Químicos del Agua/análisis
3.
EBioMedicine ; 82: 104147, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35835713

RESUMEN

BACKGROUND: The contamination of ecosystem compartments by microplastics (MPs) is an ubiquitous problem. MPs have been observed in mice tissues, and recently in human blood, stool and placenta. However, two aspects remain unclear: whether MPs accumulate in peripheral organs, specifically in the liver, and if liver cirrhosis favours this process. We aimed to examine human liver tissue samples to determine whether MPs accumulate in the liver. METHODS: This proof-of-concept case series, conducted in Germany, Europe, analyzed tissue samples of 6 patients with liver cirrhosis and 5 individuals without underlying liver disease. A total of 17 samples (11 liver, 3 kidney and 3 spleen samples) were analyzed according to the final protocol. A reliable method for detection of MP particles from 4 to 30 µm in human tissue was developed. Chemical digestion of tissue samples, staining with Nile red, subsequent fluorescent microscopy and Raman spectroscopy were performed. Morphology, size and composition of MP polymers were assessed. FINDINGS: Considering the limit of detection, all liver, kidney and spleen samples from patients without underlying liver disease tested negative for MPs. In contrast, MP concentrations in cirrhotic liver tissues tested positive and showed significantly higher concentrations compared to liver samples of individuals without underlying liver disease. Six different microplastic polymers ranging from 4 to 30 µm in size were detected. INTERPRETATION: This proof-of-concept case series assessed the presence of MPs in human liver tissue and found six different MP polymers in the liver of individuals with liver cirrhosis, but not in those without underlying liver disease. Future studies are needed to evaluate whether hepatic MP accumulation represents a potential cause in the pathogenesis of fibrosis, or a consequence of cirrhosis and portal hypertension. FUNDING: No funding was received for conducting this investigator driven study.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Animales , Ecosistema , Monitoreo del Ambiente , Humanos , Cirrosis Hepática , Ratones , Plásticos/química , Polímeros , Contaminantes Químicos del Agua/análisis
4.
Environ Pollut ; 267: 115507, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32896764

RESUMEN

The investigation of microplastics (MPs) in freshwater has received increased attention within the last decade. To date, sampling is mainly conducted at the surface of both rivers and lakes and only a few studies assessed the vertical distribution of MPs in the water column of freshwater bodies. To contribute to the understanding of MP pollution in the water column of freshwater lakes, this study evaluated the vertical profile of MPs in Lake Tollense considering particles between 63 and 5000 µm in size. Sampling was conducted on three occasions at three depths (surface, 7 m and 10 m) along a transect including eight sampling stations. The retrieved samples were digested with hydrogen peroxide and sodium hypochlorite and investigated via Nile Red staining and fluorescence microscopy. Subsequently, a sub-sample of stained particles was verified by µRaman-spectroscopy. The vertical distribution of MPs in Lake Tollense differed considerably between particle shapes (irregular particles (IPs) and fibers). Fibers did not show a noticeable pattern with depth and ranged between 22 fibers m-³ at 0 m to 19 fibers m-³ at 10 m. In contrast, IPs were distinctly less abundant in sub-surface samples with concentrations between 50 IPs m-³ at 0 m to 29 IPs m-³ at 10 m. Concerning IPs, buoyant polymers (mainly PE and PP) and concerning fibers PET and PP dominated the polymeric composition. Besides particle inherent properties, wind-induced mixing is likely affecting the intensity of vertical concentration gradients. This study highlights the need for depth-integrated sampling approaches in order to achieve representative data without over- or underestimating the overall abundances.


Asunto(s)
Lagos , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Sedimentos Geológicos , Microplásticos , Plásticos , Contaminantes Químicos del Agua/análisis
5.
Environ Pollut ; 254(Pt A): 112970, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31377328

RESUMEN

To broaden the understanding of sources, pathways and sinks for microplastic pollution in the environment, the exact and representative determination of pollution levels is crucial. Still, sampling techniques differ greatly between studies and the influence of these differences is not fully understood. Thus, we evaluate the representativeness of manta trawling and pump sampling for microplastics in a freshwater lake. While large microplastics are not captured by most pump sampling approaches due to their low abundance, small and fibrous microplastics pass the relatively coarse nets of volume-reduced techniques. Testing different water volumes for pump samples, we show that sample volumes should be large enough to minimize overestimation induced by scaling up results. Moreover, we discuss the influence of sample numbers for microplastic analysis. Finally, we argue that manta trawling and pump sampling are complementary techniques, as they cover different parts of the overall microplastic pollution.


Asunto(s)
Monitoreo del Ambiente/métodos , Lagos/química , Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Contaminación Química del Agua/análisis , Nanoestructuras/análisis
6.
Mar Pollut Bull ; 128: 601-608, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29571412

RESUMEN

Microplastic contamination in surface waters of the South Funen Archipelago in Denmark was assessed. Therefore, ten manta trawls were conducted in June 2015. Moreover, 31 low-volume bulk samples were taken to evaluate, whether consistent results in comparison to the net-based approach can be obtained. Microplastic contamination in the South Funen Archipelago (0.07 ±â€¯0.02 particles/m3) is slightly below values reported before. The sheltered position of the study area, low population pressure on adjacent islands and the absence of any major potential point sources were identified as major factors explaining the low concentration of microplastics. Within the Archipelago, harbors or marinas and the associated vessel traffic are the most probable sources of microplastics. The concentration of microplastics in low-volume bulk samples is not comparable to manta trawl results. This is mainly due to insufficient representativeness of the bulk sample volumes.


Asunto(s)
Conservación de los Recursos Hídricos/métodos , Monitoreo del Ambiente/métodos , Sedimentos Geológicos/química , Plásticos/análisis , Agua de Mar/química , Contaminantes Químicos del Agua/análisis , Dinamarca , Océanos y Mares
7.
Mar Pollut Bull ; 126: 263-274, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29421097

RESUMEN

To extent the understanding on microplastics in the marine environment we performed a case study at four beaches on the Isle of Rügen considering abundance and spatial distribution of microplastics in beach sediments. For the analysis, density separation via a glass elutriation column was implemented. In advance, efficiencies were tested for two polymers, being not buoyant in water. Recovery rates of 80% for PET and 72% for PVC particles in sandy samples were achieved. A median abundance of 88.10 (Q1=55.01/Q3=114.72) microplastic particles per kg dry sediment or 2862.56 (Q1=1787.34/Q3=3727.28) particles per m2 was found at the beaches on Rügen. Fibers were more abundant than fragments at all beaches. In this study, no statistically significant differences but only tendencies were determined between the beaches with different exposition and anthropogenic activity as well as for distribution patterns which showed that microplastic fragments accumulate in topographic depressions, similar to macrolitter items.


Asunto(s)
Sedimentos Geológicos/análisis , Plásticos/aislamiento & purificación , Residuos/análisis , Playas , Monitoreo del Ambiente , Vidrio , Agua , Contaminantes Químicos del Agua
8.
Mar Pollut Bull ; 115(1-2): 297-306, 2017 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-27993369

RESUMEN

The abundance, weight and composition of marine debris were determined at the northwest coast of the Isle of Rügen in 2015. A total number of 1115 macrolitter items were registered, resulting in an abundance of 304±88.96 items per 100m of beach length and therefore being greater than the abundances found for other beaches at the Baltic Sea. Macrolitter items were predominantly composed of plastic, on average 83%. The four beaches under investigation have different exposition as well as touristic levels. The differing influence of wind and water currents as well as recreational activities on the macrolitter at these beaches was detectable. The distribution of items within a beach segment was analyzed by implementing D-GPS and drone aerial photography. The results of this analysis suggested that the identity of the substrate as well as the presence of vegetation are both major influencing factors in the macrolitter distribution.


Asunto(s)
Playas , Monitoreo del Ambiente , Plásticos , Residuos , Alemania
9.
Environ Pollut ; 213: 648-657, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27104923

RESUMEN

Rivers and effluents have been identified as major pathways for microplastics of terrestrial sources. Moreover, lakes of different dimensions and even in remote locations contain microplastics in striking abundances. This study investigates concentrations of microplastic particles at two lakes in central Italy (Lake Bolsena, Lake Chiusi). A total number of six Manta Trawls have been carried out, two of them one day after heavy winds occurred on Lake Bolsena showing effects on particle distribution of fragments and fibers of varying size categories. Additionally, 36 sediment samples from lakeshores were analyzed for microplastic content. In the surface waters 2.68 to 3.36 particles/m(3) (Lake Chiusi) and 0.82 to 4.42 particles/m(3) (Lake Bolsena) were detected, respectively. Main differences between the lakes are attributed to lake characteristics such as surface and catchment area, depth and the presence of local wind patterns and tide range at Lake Bolsena. An event of heavy winds and moderate rainfall prior to one sampling led to an increase of concentrations at Lake Bolsena which is most probable related to lateral land-based and sewage effluent inputs. The abundances of microplastic particles in sediments vary from mean values of 112 (Lake Bolsena) to 234 particles/kg dry weight (Lake Chiusi). Lake Chiusi results reveal elevated fiber concentrations compared to those of Lake Bolsena what might be a result of higher organic content and a shift in grain size distribution towards the silt and clay fraction at the shallow and highly eutrophic Lake Chiusi. The distribution of particles along different beach levels revealed no significant differences.


Asunto(s)
Sedimentos Geológicos/análisis , Lagos/análisis , Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Viento , Monitoreo del Ambiente , Italia , Tamaño de la Partícula , Material Particulado/análisis
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