38 resultados para fluoranthene


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Polycyclic aromatic hydrocarbons (PAHs) are common environmental contaminants which can be derived from anthropogenic sources, such as combustion and discharges from extraction and transport, and natural processes, including leakage and erosion of fossil carbon. Natural PAH sources contribute, along with biological activities and terrestrial run-off, to the organic carbon content in sediments.The Barents Sea region is far from many anthropogenic sources of PAH, but production and trans-shipment of hydrocarbons is increasing. We present data for polycyclic aromatic hydrocarbon (PAH) concentrations in bottom sediments from 510 stations in the Barents and White Seas, and along the northern coast of Norway.

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We identify geochemical features of sedimentary organic matter in various morphostructural zones of the Antarctic sector of the Atlantic. We present background geochemical organic parameters for shelf and deep-sea sediments from the Weddell and Scotia Seas and the Bransfield Strait. Geochemical organic parameters are good indicators of environmental and facial variations in sediments and could be used for environmental monitoring of the World Ocean.

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Perna viridis from the Bay of Jakarta was exposed to different concentrations (0, 21.6, 216 and 2160 mg/l) of PVC microplastic particles for 91 days in a controlled laboratory experiment. Particles were negatively buoyant, but were regularly resuspended from the sediment, mimicking tidal events. The particles were contaminated with the organic pollutant fluoranthene, except for one control group, which was exposed to the highest plastic concentration (2160 mg/l) but with clean particles. Within the 91 days survival was monitored. After 40 - 44 days of the exposure, physiological responses of all mussel individuals were measured. Respiration rates were measured as the decrease of oxygen in a sealed container in 20 minutes. Clearance rates were determined by measuring the depletion of algal cells in the water in 30 minutes. Byssus production was assessed by counting the number of newly formed byssus discs within 24 hours.

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Data are presented on concentration and composition of aliphatic and polycyclic aromatic hydrocarbons (HC) in water, suspended matter (collected with a Juday net and by a separator), and in bottom sediments of the White Sea. It was found that during the last years the level of aliphatic HC concentrations in waters of the White Sea (aver. 18 µg/l) practically did not change and was comparable with average concentrations in shelf areas of the World Ocean. In water and bottom sediments distribution of HC is determined by discharge of river marginal filters. Here sedimentation of the bulk of anthropogenic HC occurs. That is why a grain-size controlling factor is not active in the zone of the river depocenter (in particular, of the North Dvina River). The same reasons most probably may explain differences in degree of geochemical relationships between contents of TOC and HC in suspended matter and bottom sediments. After passing through marginal filters natural HC are dominant in all migration forms.