RESUMEN
Concerns regarding microplastic (MP) contamination in aquatic ecosystems and its impact on seafood require a better understanding of human dietary MP exposure including extensive monitoring. While conventional techniques for MP analysis like infrared or Raman microspectroscopy provide detailed particle information, they are limited by low sample throughput, particularly when dealing with high particle numbers in seafood due to matrix-related residues. Consequently, more rapid techniques need to be developed to meet the requirements of large-scale monitoring. This study focused on semi-automated fluorescence imaging analysis after Nile red staining for rapid MP screening in seafood. By implementing RGB-based fluorescence threshold values, the need for high operator expertise to prevent misclassification was addressed. Food-relevant MP was identified with over 95% probability and differentiated from natural polymers with a 1% error rate. Comparison with laser direct infrared imaging (LDIR), a state-of-the-art method for rapid MP analysis, showed similar particle counts, indicating plausible results. However, highly variable recovery rates attributed to inhomogeneous particle spiking experiments highlight the need for future development of certified reference material including sample preparation. The proposed method demonstrated suitability of high throughput analysis for seafood samples, requiring 0.02-0.06 h/cm2 filter surface compared to 4.5-14.7 h/cm with LDIR analysis. Overall, the method holds promise as a screening tool for more accurate yet resource-intensive MP analysis methods such as spectroscopic or thermoanalytical techniques.
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Oxazinas , Alimentos Marinos , Alimentos Marinos/análisis , Oxazinas/análisis , Contaminación de Alimentos/análisis , Microplásticos/análisis , Animales , Contaminantes Químicos del Agua/análisis , Coloración y Etiquetado/métodos , Plásticos/análisis , Humanos , Colorantes Fluorescentes/químicaRESUMEN
INTRODUCTION: Electronic cigarettes and "vaping" have become popular since their appearance in Europe and the USA in approximately 2006. They are often perceived as having fewer health risks than conventional cigarettes, which makes them of interest as a support tool in smoking cessation. However, its efficacy regarding cessation or reduction of smoking under real-life conditions remains controversial. Our objective was to clarify this question in an observational study of smoking habits after initiating vaping without targeted intervention, as compared to a validated cessation programme. METHODS: From October 2015 to April 2018, 80 subjects (60 in the e-cigarette group and 20 in the supervised smoking cessation group) were included in two trial visits, one at the start of the trial and the second after 3 months, plus 4 questionnaire surveys: at the start of the trial and after a 1, 2, and 3 month period. The questionnaire included a nicotine use inventory, a modified Fagerström test for nicotine dependence, and the WHO-QOL-BREF survey. RESULTS: E-cigarettes were effective, leading to a significant (p < 0.03) reduction (p < 0.03) in tobacco consumption and nicotine dependence, with an abstinence rate of 43% after 3 months. Compared to participants in the smoking cessation programme, their use was not associated with an improvement in quality of life during the quitting attempt, and there were no significant differences in clinical symptoms between groups. The reduction in nicotine dependence was more pronounced (p < 0.012) for the smoking cessation programme, with higher abstinence rates (p = 0.011 after 12 weeks) and lower (p < 0.003) remaining tobacco consumption compared to electronic cigarettes. DISCUSSION/CONCLUSIONS: The use of electronic cigarettes reduced nicotine dependence and tobacco consumption, but a supervised smoking cessation programme was superior in terms of achieved cessation in both regards. Electronic cigarettes did not improve the quality of life. Since e-cigarettes could be associated with long-term health risks, their usefulness in smoking cessation remains questionable, and a professionally guided and validated smoking cessation programme still appears to be superior and preferable, in terms of achieved cessation. Although this trial is limited regarding the number of participants and follow-up time, it highlights the need for additional, large clinical trials evaluating the efficacy of e-cigarettes for smoking cessation in comparison to a professionally guided smoking cessation programme.
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Sistemas Electrónicos de Liberación de Nicotina , Calidad de Vida , Cese del Hábito de Fumar , Tabaquismo , Vapeo , Humanos , Cese del Hábito de Fumar/métodos , Cese del Hábito de Fumar/psicología , Masculino , Femenino , Vapeo/psicología , Adulto , Persona de Mediana Edad , Tabaquismo/psicología , Encuestas y Cuestionarios , Fumar/psicología , Fumar/terapiaRESUMEN
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.
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Microplásticos , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Sedimentos Geológicos , Alemania , Lagos , Plásticos , Contaminantes Químicos del Agua/análisisRESUMEN
Studies on macroplastic pollution in freshwater systems are rare compared to the marine environment. Nevertheless, freshwater systems are worthy to be equally investigated as they are pathways of plastic to the ocean and lakes may act as (temporary) sinks. The aim of this study was to identify sources for plastics and influences on its distribution in a limnic environment. Anthropogenic litter (>5 mm) was monitored semi-annually over a three-year period at four sandy bank border segments of Lake Tollense in Mecklenburg-Western Pomerania, Germany. The selected beaches represent different expositions and vary in their level of anthropogenic activity. Considering all six samplings, mean abundance of anthropogenic litter is 0.2 ± 0.1 items/m2 or 130.9 ± 91.0 items/100 m beach length. The averaged mass of anthropogenic litter is 0.5 ± 1.0 g/m2 or rather 218.7 ± 284.6 g/100 m. Plastic consistently is the predominate material (72%) and cigarette butts are the most found items. A higher pollution by anthropogenic litter is found at the end of tourist season unveiling the impact of anthropogenic activity on litter abundance. Additionally, litter transport via tributaries into the lake plays a role. Testing the detection of anthropogenic litter via aerial images taken by unmanned aerial vehicles resulted in good recovery rates when minimizing the flight height. Furthermore, the analysis of anthropogenic litter distribution displayed on the images showed litter accumulation areas at the border of sandy beach areas. The deployment of marine guidelines in a freshwater environment did work well, however, small changes in the protocol are suggested for future lake beach studies dealing with anthropogenic litter pollution.
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Playas , Lagos , Monitoreo del Ambiente , Alemania , Plásticos , Residuos/análisisRESUMEN
A variety of methods concerning the identification of microplastics in environmental samples exist. While visual identification is often used, implemented easily, and cost-efficient but implying biased results, spectroscopic or chromatographic approaches are reliable but time-consuming and need specific equipment. Nile red staining is an available alternative and complement method for identifying microplastics. In this study, Nile red staining and subsequent photographing in a UV light photobox was tested on its reliability and feasibility. The approach was compared with a second identification process using again staining but a fluorescence microscope. Selected identified microplastic particles were analyzed by µ-Raman spectroscopy to prove their polymeric origin. The results show that the presented approach is faster compared with the use of a fluorescence microscope or µ-Raman spectroscopy. Furthermore, it is cost-effective as well as accurate for large microplastics > 0.63 mm and, therefore, may be applied when large sample volumes need to be analyzed. Graphical abstract.
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Monitoreo del Ambiente/métodos , Oxazinas , Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Colorantes Fluorescentes/química , Oxazinas/química , Tamaño de la Partícula , Plásticos/química , Reproducibilidad de los Resultados , Espectrometría Raman , Coloración y Etiquetado , Contaminantes Químicos del Agua/químicaRESUMEN
OBJECTIVES: The aim of this study was to compare environmental contamination of cyclophosphamide (CP) during 1 week of drug compounding by conventional manual procedure in a biological safety cabinet (BSC) with laminar airflow and a new robotic drug preparation system (APOTECAchemo). METHODS: During four consecutive days, similar numbers of infusion bags with cyclophosphamide were prepared with both techniques in a cross-over design. Wipe samples (49 for BSC, 50 for APOTECAchemo) were taken at several locations (gloves, infusion bags, trays, BSC-benches, floor) in the pharmacy and analyzed for CP concentrations by GC-MSMS (LOD 0.2 ng/sample). RESULTS: The detection rate was 70% in the BSC versus 15% in APOTECAchemo. During manual preparation of admixtures using BSC contamination with CP was below 0.001 ng/cm(2) at most locations, but significant on gloves (0.0004-0.0967 ng/cm(2)) and the majority (70%) of infusion bags (<0.0004-2.89 ng/cm(2)). During robotic preparation by APOTECAchemo, gloves (1 of 8: 0.0007 ng/cm(2)) and infusion bags (3 of 20: 0.0005, 0.0019, 0.0094 ng/cm(2)) were considerably less contaminated. Residual contamination was found on the surfaces under the dosing device in the compounding area (0.0293-0.1603 ng/cm(2)) inside the robotic system. CONCLUSIONS: Compared to outcomes of other studies, our results underline good manufacturing procedures in this pharmacy with low contamination for both techniques (BSC and APOTECAchemo). Comparison of both preparation procedures validated that contamination of infusion bags was much lower by using the robotic system.
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Antineoplásicos/química , Ciclofosfamida/química , Contaminación de Equipos/prevención & control , Contaminación de Medicamentos/prevención & control , Monitoreo del Ambiente/métodos , Exposición Profesional/prevención & control , Farmacias , Servicio de Farmacia en Hospital/métodos , Equipos de Seguridad , Robótica/métodosRESUMEN
Occupational exposure to antineoplastic drugs has been documented for decades showing widespread contamination in preparation and administration areas. Apart from preventive measures, efficient cleaning of surfaces is indispensable to minimize the exposure risk. The aim of this study was to evaluate the efficiency of three cleaning agents after intentional contamination by gemcitabine (GEM) and 5-fluorouracile (5-FU) on four different surface types usually installed in healthcare settings. Glass, stainless steel, polyvinylchloride (PVC), and laminated wood plates were contaminated with 20 ng/µl GEM and 2 ng/µl 5-FU solutions. Wipe samples were analyzed for drug residues after cleaning with a) distilled water, b) aqueous solution containing sodium dodecyl sulfate (10 mM) and 2-propanol (SDS-2P), and c) Incides N (pre-soaked) alcoholic wipes. Quantification was performed by high-performance liquid chromatography (HPLC) for GEM and gas chromato-graphy-tandem mass spectrometry (GCMS/MS) for 5-FU. Recovery was determined and cleaning efficiency was calculated for each scenario. Mean recoveries were 77-89% for GEM and 24-77% for 5-FU and calculated cleaning efficiencies ranged between 95 and 100% and 89 and 100%, respectively. Residual drug amounts were detected in the range nd (not detected) - 84 ng GEM/sample and nd - 6.6 ng 5-FU/sample depending on surface type and cleaning agent. Distilled water and SDS-2P had better decontamination outcomes than Incides N wipes on nearly all surface types, especially for GEM. Regarding 5-FU, the overall cleaning efficiency was lower with highest residues on laminated wood surfaces. The tested cleaning procedures are shown to clean glass, stainless steel, PVC, and laminated wood with an efficiency of 89-100% after contamination with GEM and 5-FU. Nevertheless, drug residues could be verified by wipe samples. Pure distilled water and SDS in an alcoholic-aqueous solution expressed an efficient cleaning performance, especially with respect to GEM. The study results demonstrate the need to adapt cleaning procedures to the variety of drugs and surface types to develop effective decontamination strategies.
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Antineoplásicos/análisis , Descontaminación/métodos , Desoxicitidina/análogos & derivados , Contaminación de Equipos/prevención & control , Fluorouracilo/análisis , Alcoholes , Desoxicitidina/análisis , Vidrio , Exposición Profesional/prevención & control , Cloruro de Polivinilo , Acero Inoxidable , Tensoactivos , Agua , Madera , GemcitabinaRESUMEN
Atmospheric microplastic deposition rates play a crucial role for calculating the input of microplastics in the environment and to further understand pollution patterns. In this study, the spatial and temporal distribution of atmospheric microplastic particles in urban and rural areas of Northern Germany was investigated. Therefore, eleven structurally diverse locations in Hamburg and Mecklenburg-Western Pomerania were equipped with bulk-deposition samplers in triplicates and sampled monthly between August 2019 and July 2020. The resulting 306 samples were treated with hydrogen peroxide (30 %) and sodium hypochlorite (6-14 %) to digest biological organic matter. The filters were subsequently stained with the lipophilic dye Nile Red and underwent visual microplastic identification via fluorescence microscopy. Fragments and fibers were quantified down to a cut-off size of 10 µm. The polymer composition of microplastic particles was investigated along a subset of particles via µ-Raman spectroscopy. The microplastic deposition rate for Northern Germany (89 ± 61 MP/m2/day) is in the same order of magnitude as those reported by previous studies. Significant differences in microplastic deposition rates were found between urban and rural sampling sites. Population density was identified as an important factor for greater amounts of microplastics and higher shares of fibers in urban samples. Special attention was given to the canopy cover at two forested sampling sites and an influence of the comb-out effect on atmospheric microplastic deposition was detected.
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Monitoring strategies are becoming increasingly important as microplastic contamination increases. To find potentially suitable organisms and sites for biota monitoring in the German Wadden Sea, we collected invertebrates (n = 1585), fish (n = 310), and sediment cores (n = 12) at 10 sites along the coast of Lower Saxony between 2018 and 2020. For sample processing of biota, the soft tissue was digested and the sediment samples additionally underwent a subsequent density separation step. Microplastic particles were identified using Nile red and fluorescence microscopy, followed by polymer composition analysis of a subset of particles via µRaman spectroscopy. All investigated species, sediment cores, and sites contained microplastics, predominantly in the morphology class of fragments. Microplastics were found in 92% of Arenicola marina, 94% of Littorina littorea, 85% of Mytilus edulis, and 79% of Platichthys flesus, ranging from 0 to 248.1 items/g. Sediment core samples contained MPs ranging from 0 to 8128 part/kg dry weight of sediment. In total, eight polymers were identified, predominantly consisting of polyethylene, polyvinylchloride, and polyethylene terephthalate. Considering the sampling, processing, and results, the species Mytilus edulis and Platichthys flesus are suitable species for future microplastic monitoring in biota.
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15 filtration samples were collected at eight locations onboard the RV Sonne (cruise SO279 in 2020) from 6 m water depth using a fractionated stainless-steel filtration unit. The size fraction > 300 µm was visually examined and potential microplastic particles were analyzed by ATR-FTIR spectroscopy. The treatment of size class 20 µm < d < 300 µm was based on enzymatic-oxidative microwave-assisted "one-pot" matrix digestion in conjunction with analysis of the microplastics by time-efficient LDIR imaging. Total number concentrations ranged from 47 to 2154 microplastic particles per m3 (average for all stations: 500 ± 700 microplastic particles m-3 (1 SD; n = 8)). In total, 20 polymer types were identified. The most common polymer types were polyethylene terephthalate (20 %) and acrylates/polyurethane/varnish (15 %). 93 % of the detected microplastics were smaller than 100 µm in length. Analysis of sample replicates indicates high spatio-temporal variations in microplastic pollution within the investigated region.
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Microplásticos , Contaminantes Químicos del Agua , Microplásticos/análisis , Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Polímeros , Océano Atlántico , Agua/análisisRESUMEN
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.
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Microplásticos , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Plásticos , Agua , Contaminantes Químicos del Agua/análisisRESUMEN
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.
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Microplásticos , Contaminantes Químicos del Agua , Animales , Ecosistema , Monitoreo del Ambiente , Humanos , Cirrosis Hepática , Ratones , Plásticos/química , Polímeros , Contaminantes Químicos del Agua/análisisRESUMEN
BACKGROUND: Regarding the multiple health effects of e-cigarettes, there are insufficient data on potential effects on bronchial reactivity (BHR). In the present study, we assessed the impact of a switch from conventional to e-cigarettes on BHR under realistic conditions over a period of 3 months. METHODS: Sixty subjects who declared to reduce or stop their tobacco consumption by inhalation of nicotine-containing liquids via e-cigarette, and 20 volunteers participating in a stop-smoking program were included. Data was analysed using parametric and non-parametric statistical procedures. Spirometry, determinations of exhaled carbon monoxide (eCO) and nitric oxide (FeNO), provocation testing with mannitol as an indirect bronchial stimulus, and cotinine measurements were used to investigate BHR and nicotine abstinence. RESULTS: BHR to mannitol significantly decreased in the group using e-cigarettes and nicotine-containing liquids over a period of three months in this real-life setting. Participants reduced their tobacco consumption to about 25% or lower, confirmed by a reduction in eCO. Changes in lung function and FeNO were small and not statistically significant, and changes in the stop-smoking group were similar to those in the e-cigarette group. CONCLUSION: The reduction in BHR that can be expected after a reduction of cigarette consumption was not abolished by the concomitant use of e-cigarettes. Whether the decrease in BHR observed after 3 months is maintained when using e-cigarettes over longer time periods or has an individual prognostic value, must be clarified in long-term studies.
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Bronquios/fisiología , Pruebas de Provocación Bronquial/métodos , Sistemas Electrónicos de Liberación de Nicotina , Pulmón/fisiología , Manitol/farmacología , Cese del Hábito de Fumar/métodos , Fumar Tabaco/efectos adversos , Vapeo , Bronquios/fisiopatología , Monóxido de Carbono/metabolismo , Femenino , Humanos , Masculino , Óxido Nítrico/metabolismo , Espirometría , Encuestas y Cuestionarios , Factores de TiempoRESUMEN
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.
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Lagos , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Sedimentos Geológicos , Microplásticos , Plásticos , Contaminantes Químicos del Agua/análisisRESUMEN
Only few studies investigated the input of microplastic particles via the atmosphere, so far. Here, we present results on microplastic concentrations in the atmospheric deposition in the metropolitan region of Hamburg. In total, six investigation sites were equipped with three bulk precipitation samplers each and sampled biweekly over 12â¯weeks (12/17-03/18). Three sites were located in a rural area south of Hamburg comprising one open field site and two throughfall sites under beech/oak and Douglas fir forest canopy, respectively. Three further sites were selected within the city following a transect from north to south representing urban sites of varying degrees concerning population, traffic and industrial pressures. Particles and fibers were counted under UV light within a photo box and under a fluorescence microscope (Axio Lab A.1, Zeiss). Results show that microplastic particles are ubiquitous at all sites. A median abundance between 136.5 and 512.0 microplastic particles per m2/day has been found over the sampling period. This equals a mean microplastic abundance of 275â¯particles/m2/day µRaman spectroscopy showed that polyethylenes/ethylvinyl acetate copolymers are dominating significantly (48.8 and 22.0%, respectively), 16 particles analyzed (14.6%) were identified as contamination from PE (polyethylene) samplers. In contrast to other studies, fragments were significantly dominating compared to fibers. The spatial distribution comparing the urban sites concentrations followed in the order from high to low: "north" (Henstedt-Ulzburg, low population density, suburb) - "center" (University; large population density) - "south" (Wilhelmsburg, middle population density, port and industrial facilities) with highly varying concentrations within the time series. Surprisingly, the rural sites in the southern part of Hamburg showed highest concentrations (Douglas fir > open field > beech/oak). This finding is most likely a result of factors such as the comb out capacity of the different forest types and/or direct input pathways from the agricultural areas and the nearby highway.
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Contaminantes Atmosféricos/análisis , Atmósfera/química , Monitoreo del Ambiente , Plásticos/análisis , AlemaniaRESUMEN
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.
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Monitoreo del Ambiente/métodos , Lagos/química , Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Contaminación Química del Agua/análisis , Nanoestructuras/análisisRESUMEN
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¯0.02â¯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.
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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 MaresRESUMEN
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.
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Sedimentos Geológicos/análisis , Plásticos/aislamiento & purificación , Residuos/análisis , Playas , Monitoreo del Ambiente , Vidrio , Agua , Contaminantes Químicos del AguaRESUMEN
BACKGROUND: Activation of the AMP-activated protein kinase (AMPK) is an attractive approach for the treatment of type 2 diabetes. AMPK activation reduces glucose levels in animal models of type 2 diabetes by increasing glucose uptake in skeletal muscles and reducing hepatic glucose production. Furthermore, AMPK activation ameliorates hepatic steatosis in animal models. For the clinical development of AMPK activators it is essential to have a reliable target engagement marker for appropriate dose finding and to support proof of clinical principle. While the activation of AMPK by quantification of the phosphorylation of AMPK at Thr172 in target tissues can be assessed pre-clinically, this is not feasible in clinical studies. Therefore, we attempted to identify and translate a peripheral target engagement biomarker downstream of AMPK activation for clinical use in blood samples. METHODS: For pharmacological activation of AMPK, two AMPK activators were synthesized (compound 1 and 2). A compound with structural similarities but no pharmacological effect on AMPK phosphorylation was synthesized as negative control (compound 3). Whole blood from healthy volunteers was incubated with an AMPK activator for up to 6 hours and mRNA sequencing was performed. Additionally, human PBMCs were isolated to evaluate Thr172-phosphorylation of AMPK in Western blots. In order to enable identification of translatable biomarker candidates, blood samples from HanWistar rats treated for two weeks with an AMPK activator were also subjected to mRNA sequencing. Furthermore, concentration-response curves for four biomarker candidates were recorded in human blood samples using Nanostring nCounter technology. Finally, ZDF rats were treated with increasing doses of compound 2 for five weeks to investigate the glucose-lowering efficacy. To investigate changes of mRNA expression of two selected biomarker candidates in this ZDF rat study, qRT-PCR was performed. RESULTS: Pharmacological activation of AMPK in human PBMCs revealed an increase in Thr172-phosphorylation of AMPK, confirming target engagement in these blood cells. RNA sequencing of human blood samples identified 608 deregulated genes after AMPK activation. Additionally, AMPK activation led to deregulation of 367 genes in whole blood from HanWistar rats which mapped to the respective human genes. 22 genes out of the intersection of genes deregulated in both species are proposed as potential translatable target engagement biomarker candidates. The most prominent genes were transmembrane glycoprotein NMB (GPNMB, osteoactivin), calcium-binding protein A9 (S100A9), peptidoglycan recognition protein (PGLYRP1) and Ras homolog gene family, member B (RHOB). Specificity for AMPK was shown by testing inactive compound 3 in HanWistar rats. The exposure-effect relationship for GPNMB was investigated in a subchronic study in diabetic ZDF rats. GPNMB showed a dose-dependent up-regulation both acutely and after subchronic dosing. GPNMB up-regulation correlated with an increased Thr172-phosphorylation of AMPK in liver and quadriceps muscle in rats. CONCLUSION: GPNMB has been identified as a translatable target engagement biomarker for use in clinical studies.
Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Descubrimiento de Drogas , Terapia Molecular Dirigida , Animales , Biomarcadores/metabolismo , Activación Enzimática/efectos de los fármacos , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Mioblastos/efectos de los fármacos , Mioblastos/metabolismo , Fosforilación/efectos de los fármacos , Ratas , Análisis de Secuencia de ARN , Treonina/metabolismoRESUMEN
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.