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1.
PLoS One ; 18(3): e0281596, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36888681

RESUMEN

As global awareness, science, and policy interventions for plastic escalate, institutions around the world are seeking preventative strategies. Central to this is the need for precise global time series of plastic pollution with which we can assess whether implemented policies are effective, but at present we lack these data. To address this need, we used previously published and new data on floating ocean plastics (n = 11,777 stations) to create a global time-series that estimates the average counts and mass of small plastics in the ocean surface layer from 1979 to 2019. Today's global abundance is estimated at approximately 82-358 trillion plastic particles weighing 1.1-4.9 million tonnes. We observed no clear detectable trend until 1990, a fluctuating but stagnant trend from then until 2005, and a rapid increase until the present. This observed acceleration of plastic densities in the world's oceans, also reported for beaches around the globe, demands urgent international policy interventions.


Asunto(s)
Esmog , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Plásticos , Monitoreo del Ambiente , Océanos y Mares , Residuos/análisis
2.
Sci Rep ; 6: 37551, 2016 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-27876837

RESUMEN

The Mediterranean Sea has been recently proposed as one of the most impacted regions of the world with regards to microplastics, however the polymeric composition of these floating particles is still largely unknown. Here we present the results of a large-scale survey of neustonic micro- and meso-plastics floating in Mediterranean waters, providing the first extensive characterization of their chemical identity as well as detailed information on their abundance and geographical distribution. All particles >700 µm collected in our samples were identified through FT-IR analysis (n = 4050 particles), shedding for the first time light on the polymeric diversity of this emerging pollutant. Sixteen different classes of synthetic materials were identified. Low-density polymers such as polyethylene and polypropylene were the most abundant compounds, followed by polyamides, plastic-based paints, polyvinyl chloride, polystyrene and polyvinyl alcohol. Less frequent polymers included polyethylene terephthalate, polyisoprene, poly(vinyl stearate), ethylene-vinyl acetate, polyepoxide, paraffin wax and polycaprolactone, a biodegradable polyester reported for the first time floating in off-shore waters. Geographical differences in sample composition were also observed, demonstrating sub-basin scale heterogeneity in plastics distribution and likely reflecting a complex interplay between pollution sources, sinks and residence times of different polymers at sea.

3.
PLoS One ; 9(12): e111913, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25494041

RESUMEN

Plastic pollution is ubiquitous throughout the marine environment, yet estimates of the global abundance and weight of floating plastics have lacked data, particularly from the Southern Hemisphere and remote regions. Here we report an estimate of the total number of plastic particles and their weight floating in the world's oceans from 24 expeditions (2007-2013) across all five sub-tropical gyres, costal Australia, Bay of Bengal and the Mediterranean Sea conducting surface net tows (N = 680) and visual survey transects of large plastic debris (N = 891). Using an oceanographic model of floating debris dispersal calibrated by our data, and correcting for wind-driven vertical mixing, we estimate a minimum of 5.25 trillion particles weighing 268,940 tons. When comparing between four size classes, two microplastic <4.75 mm and meso- and macroplastic >4.75 mm, a tremendous loss of microplastics is observed from the sea surface compared to expected rates of fragmentation, suggesting there are mechanisms at play that remove <4.75 mm plastic particles from the ocean surface.


Asunto(s)
Océanos y Mares , Plásticos , Contaminación del Agua , Hidrodinámica , Modelos Lineales , Modelos Teóricos , Viento
4.
Front Neuroinform ; 8: 65, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25071542

RESUMEN

The XNAT informatics platform is an open source data management tool used by biomedical imaging researchers around the world. An important feature of XNAT is its highly extensible architecture: users of XNAT can add new data types to the system to capture the imaging and phenotypic data generated in their studies. Until recently, XNAT has had limited capacity to broadcast the meaning of these data extensions to users, other XNAT installations, and other software. We have implemented a data dictionary service for XNAT, which is currently being used on ConnectomeDB, the Human Connectome Project (HCP) public data sharing website. The data dictionary service provides a framework to define key relationships between data elements and structures across the XNAT installation. This includes not just core data representing medical imaging data or subject or patient evaluations, but also taxonomical structures, security relationships, subject groups, and research protocols. The data dictionary allows users to define metadata for data structures and their properties, such as value types (e.g., textual, integers, floats) and valid value templates, ranges, or field lists. The service provides compatibility and integration with other research data management services by enabling easy migration of XNAT data to standards-based formats such as the Resource Description Framework (RDF), JavaScript Object Notation (JSON), and Extensible Markup Language (XML). It also facilitates the conversion of XNAT's native data schema into standard neuroimaging vocabularies and structures.

5.
Mar Pollut Bull ; 64(10): 2190-2, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22954615

RESUMEN

Laysan Albatrosses (Phoebastria immutabilis) and Black-footed Albatrosses (P. nigripes) ingest plastic debris, as evidenced by studies showing plastic in the digestive contents of their chicks, but there is little documentation of the frequency and amount of ingested plastics carried in foraging adults. In this study, we quantify plastics among the digestive contents of 18 Laysan Albatrosses and 29 Black-footed Albatrosses collected as by-catch in the North Pacific Ocean. We found ingested plastic in 30 of the 47 birds examined, with Laysan Albatrosses exhibiting a greater frequency of plastic ingestion (83.3% n=18) than Black-footed Albatrosses (51.7% n=29) (X(2)=4.8, df=1, P=0.03). Though the mass of ingested plastic in both species (mean±SD=0.463g±1.447) was lower than previously noted among albatross chicks, the high frequency of ingested plastic we found in this study suggests that long-term effects, e.g. absorption of contaminants from plastics, may be of concern throughout the population.


Asunto(s)
Aves , Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Animales , Ingestión de Alimentos , Monitoreo del Ambiente , Contenido Digestivo/química , Océano Pacífico , Contaminación Química del Agua/estadística & datos numéricos
6.
Mar Pollut Bull ; 60(12): 2275-8, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21067782

RESUMEN

A significant amount of marine debris has accumulated in the North Pacific Central Gyre (NPCG). The effects on larger marine organisms have been documented through cases of entanglement and ingestion; however, little is known about the effects on lower trophic level marine organisms. This study is the first to document ingestion and quantify the amount of plastic found in the gut of common planktivorous fish in the NPCG. From February 11 to 14, 2008, 11 neuston samples were collected by manta trawl in the NPCG. Plastic from each trawl and fish stomach was counted and weighed and categorized by type, size class and color. Approximately 35% of the fish studied had ingested plastic, averaging 2.1 pieces per fish. Additional studies are needed to determine the residence time of ingested plastics and their effects on fish health and the food chain implications.


Asunto(s)
Peces , Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Animales , Dieta , Monitoreo del Ambiente , Cadena Alimentaria , Contenido Digestivo/química , Océano Pacífico , Plancton , Estómago/química , Movimientos del Agua
7.
Philos Trans R Soc Lond B Biol Sci ; 364(1526): 1973-6, 2009 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-19528049

RESUMEN

Within the last few decades, plastics have revolutionized our daily lives. Globally we use in excess of 260 million tonnes of plastic per annum, accounting for approximately 8 per cent of world oil production. In this Theme Issue of Philosophical Transactions of the Royal Society, we describe current and future trends in usage, together with the many benefits that plastics bring to society. At the same time, we examine the environmental consequences resulting from the accumulation of waste plastic, the effects of plastic debris on wildlife and concerns for human health that arise from the production, usage and disposal of plastics. Finally, we consider some possible solutions to these problems together with the research and policy priorities necessary for their implementation.


Asunto(s)
Ambiente , Contaminantes Ambientales/economía , Contaminantes Ambientales/toxicidad , Plásticos/toxicidad , Política Pública , Administración de Residuos/métodos , Historia del Siglo XX , Plásticos/historia
8.
Philos Trans R Soc Lond B Biol Sci ; 364(1526): 1999-2012, 2009 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-19528052

RESUMEN

Plastic debris has significant environmental and economic impacts in marine systems. Monitoring is crucial to assess the efficacy of measures implemented to reduce the abundance of plastic debris, but it is complicated by large spatial and temporal heterogeneity in the amounts of plastic debris and by our limited understanding of the pathways followed by plastic debris and its long-term fate. To date, most monitoring has focused on beach surveys of stranded plastics and other litter. Infrequent surveys of the standing stock of litter on beaches provide crude estimates of debris types and abundance, but are biased by differential removal of litter items by beachcombing, cleanups and beach dynamics. Monitoring the accumulation of stranded debris provides an index of debris trends in adjacent waters, but is costly to undertake. At-sea sampling requires large sample sizes for statistical power to detect changes in abundance, given the high spatial and temporal heterogeneity. Another approach is to monitor the impacts of plastics. Seabirds and other marine organisms that accumulate plastics in their stomachs offer a cost-effective way to monitor the abundance and composition of small plastic litter. Changes in entanglement rates are harder to interpret, as they are sensitive to changes in population sizes of affected species. Monitoring waste disposal on ships and plastic debris levels in rivers and storm-water runoff is useful because it identifies the main sources of plastic debris entering the sea and can direct mitigation efforts. Different monitoring approaches are required to answer different questions, but attempts should be made to standardize approaches internationally.


Asunto(s)
Ecosistema , Monitoreo del Ambiente/estadística & datos numéricos , Contaminantes Ambientales/análisis , Plásticos , Residuos/análisis , Movimientos del Agua , Playas/estadística & datos numéricos , Océanos y Mares
9.
Philos Trans R Soc Lond B Biol Sci ; 364(1526): 2153-66, 2009 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-19528062

RESUMEN

Plastics have transformed everyday life; usage is increasing and annual production is likely to exceed 300 million tonnes by 2010. In this concluding paper to the Theme Issue on Plastics, the Environment and Human Health, we synthesize current understanding of the benefits and concerns surrounding the use of plastics and look to future priorities, challenges and opportunities. It is evident that plastics bring many societal benefits and offer future technological and medical advances. However, concerns about usage and disposal are diverse and include accumulation of waste in landfills and in natural habitats, physical problems for wildlife resulting from ingestion or entanglement in plastic, the leaching of chemicals from plastic products and the potential for plastics to transfer chemicals to wildlife and humans. However, perhaps the most important overriding concern, which is implicit throughout this volume, is that our current usage is not sustainable. Around 4 per cent of world oil production is used as a feedstock to make plastics and a similar amount is used as energy in the process. Yet over a third of current production is used to make items of packaging, which are then rapidly discarded. Given our declining reserves of fossil fuels, and finite capacity for disposal of waste to landfill, this linear use of hydrocarbons, via packaging and other short-lived applications of plastic, is simply not sustainable. There are solutions, including material reduction, design for end-of-life recyclability, increased recycling capacity, development of bio-based feedstocks, strategies to reduce littering, the application of green chemistry life-cycle analyses and revised risk assessment approaches. Such measures will be most effective through the combined actions of the public, industry, scientists and policymakers. There is some urgency, as the quantity of plastics produced in the first 10 years of the current century is likely to approach the quantity produced in the entire century that preceded.


Asunto(s)
Conservación de los Recursos Naturales/tendencias , Contaminación Ambiental/efectos adversos , Contaminación Ambiental/prevención & control , Plásticos , Salud Pública/tendencias , Política Pública , Administración de Residuos/métodos , Carga Corporal (Radioterapia) , Contaminación Ambiental/estadística & datos numéricos , Humanos , Medición de Riesgo/métodos
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