1,721,113 research outputs found
Bioaccumulation of persistent organic pollutants in tissues of the Greenland shark Somniosus microcephalus from NE Greenland
No full textThe Greenland shark Somniosus microcephalus was indexed as near threatened by the IUCN Red List of Threatened Species in 2012. It is an interesting species from an ecotoxicologiacl point of view being a long-lived and slow-growing deep-sea shark. Population dynamics, biology, and life cycle knowledges are still limited as well as ecotoxicological data. The aims of this study were to determine the POP concentrations in tissues (red and white muscle, brain, gonad, fat, liver) by gaschromatography, and the dioxin-like compound Toxic Equivalents (TEQs) using the TEF method in order to assess the possible risk for the analyzed specimens. The persistent organic pollutants (POPs) studied were: polychlorobyphenils (PCBs), polychlorodibenzo-dioxins and -furans (PCDDs/DFs), polybromodiphenylethers (PBDEs).
Three specimens of Greenland shark were captured by line in the Kong Oscar Fjord, Greenland Sea (North-East Greenland National Park) in August 2010, during the scientific expedition TUNU-IV in the framework of the international program TUNU-MAFIG (University of Tromsø). PCBs and PBDEs were detected in most of the samples and ranged 2.01-103 ng/g wet wt and 7.9-3050 pg/g wet wt, respectively. PCDDs/Fs were below the limit of detection in most of the samples, but showed unexpected high values when detected. The TEQ concentration (=TEQ_PCB+TEQ_PCDDs+TEQ_PCDFs) was 4.54 pg/g wet wt in white muscle; this value was higher that those found in soma bone species from the same area and the Mediterranean Sea. The Greenland shark may be at high ecotoxicological risk due to its longevity and food habits that may allow them to bioaccumulate toxic and persistent contaminants
Legacy persistent organic pollutants in the common smouth-hound (mustelus mustelus) from the Northern Adriatic Sea
No full textAn overview of POP levels and trends in Antarctic trophic webs: a starting point for future research
No full textContamination in the Antarctic ecosystems was first reported in 1966 and there has been an increasing interest in studying the presence of pollutants in this pristine polar region since then. This awareness has been growing in recent years, as the Arctic has been reported as a final sink for persistent organic pollutants (POPs). The Arctic is a perennially frozen sea surrounded by continents, Antarctica is a snow-covered continent surrounded by the Southern Ocean; besides geographical features, several factors may determine the POP occurrence and deposition, such as proximity to sources and their physicochemical properties. Degradation of deposited POPs is very slow in the polar regions due to the low temperatures and winter darkness. Moreover, ice can entrap POPs and release them into the environment, when it melts, allowing them to enter trophic webs, bioaccumulate in tissues of organisms and biomagnify
Indagine sulla contaminazione da policlorobifenili e valutazione della loro tossicità in organismi del Mare Mediterraneo e del Mare di Ross (Antartide)
No full textThe presence of polychlorinated byphenils and pesticides was evaluated in organisms of the marine trophic webs in Antarctica (Ross Sea) and in the Mediterranean Sea. The dioxin-like compounds toxicity was assessed. The profile of contamination was studied in both area and compared
Persistent Contaminants in Antarctic Marine Organisms: Contamination Profile and Temporal Trend
No full textIndustrial contaminants in Antarctic biota
No full textA critical review of the levels and patterns of industrial contaminants in biota from Antarctica and the Southern Ocean revealed that concentrations are low with respect to other regions of the world, although in some specimens/species (e.g. leopard seal, some invertebrates) they are occasionally high and comparable to those found in regions with a strong human impact; the highest levels of persistent organic pollutants (POPs) were detected in the vicinity of scientific stations. Bioconcentration prevails at the lower trophic levels of pelagic food webs, while biomagnification can become the main route of contamination at higher levels. In a benthic food web, biomagnification poses a major risk for organisms that accumulate lipids to overwinter, compared to those that accumulate glycogen. Hexachlorobenzene, DDTs and chlordanes showed similar concentrations and patterns in the 1980s-1990s period in organisms from Western and Eastern Antarctica, while the polychlorinated biphenyls time trend was different in a variety of species from the two regions
POPs in Antarctic ecosystems: is climate change affecting their temporal trends?
No full textClimate change is affecting Antarctica and the Southern Ocean and effects have been already reported for the abiotic compartments of the ecosystems, e.g. ice loss and iceberg calving. Global warming can alter also the distribution of persistent organic pollutant (POPs) both at a global scale and in the Antarctic Region, due to their physical–chemical characteristics. Effects of climate changes have been already reported on feeding behaviour and reproductive process of organisms. Another consequence for organisms includes the POP bioaccumulation. Here we review the literature reporting the linkage between recorded effects of climate changes and POP bioaccumulation in resident marine Antarctic species (fish and penguins). Notwithstanding Antarctica is a final sink for persistent contaminants due to the extreme cold climate, a general decreasing POP trend has been observed for some POPs. Their concentrations in biota are reported to be linked to ice melting and large iceberg calving; the peculiar marine Antarctic ecosystems and the pelagic-benthic coupling may also contribute to alterations in the bioaccumulation processes. These effects are similar in polar regions, although the comparison with the Arctic biota is not possible due to the lack of data in the Antarctic Region. It remains an open question if the POP amount accumulated in the Antarctic ecosystems is decreasing or not
Perfluorooctanesulfonate and related fluorochemicals in several organisms including humans from Italy
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