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Accumulation of butyltin compounds in cetaceans from Korean coastal waters Texto completo
2011
Choi, Minkyu | Moon, Hyo-Bang | An, Yong-Rock | Choi, Seok-Gwan | Choi, Hee-Gu
Data on the occurrence and accumulation profiles of butyltins (BTs), including tributyltin (TBT), in marine mammals are scarce. This is the first study to investigate residue levels and accumulation patterns of BTs in cetaceans from Korean coastal waters. The total concentrations of BTs (sum of mono- to tri-butyltins) in minke whales (Balaenoptera acutorostrata) and long-beaked common dolphins (Delphinus capensis) ranged from 15.7 to 297ng/g wet weight (mean: 100ng/g wet weight) and from 59.0 to 412ng/g wet weight (mean: 228ng/g wet weight), respectively. Dibutyltin (DBT) accounted for 63% of the total BTs in all cetacean samples. Significant species-specific differences in BT concentrations, possibly due to the differences in their habitat and diet, were found between the two cetacean species. The concentrations of DBT and TBT in most cetacean samples exceeded the threshold value for cytotoxic effects in cetaceans, implying potentially adverse health risks from exposure to BTs.
Mostrar más [+] Menos [-]Bioaccumulation depuration kinetics and effects of benzo(a)anthracene on Mytilus galloprovincialis Texto completo
2011
Yakan, S.D. | Henkelmann, B. | Schramm, K.-W. | Okay, O.S.
Polycyclic aromatic hydrocarbons (PAHs) are important environmental pollutants due to their persistence and bioaccumulation potential both in organisms and in sediments. In this study, bioaccumulation and depuration experiments were performed employing local Mediterranean mussel species, Mytilus galloprovincialis, with two biomarkers: filtration rate and lysosomal stability (neutral red retention) assay. Benzo(a)anthracene (BaA) was chosen as the model PAH compound due to its common presence in several matrices in the marine environment. Bioconcentration Factors (BCFs) for the mussels exposed to different BaA concentrations were calculated from both kinetic rate constants and from the experimental data and found between 27-3184 and 16-2745, respectively. Experimental QSAR values were found comparable to the previous QSAR models created for BaA. The effect of BaA exposure on the mussels showed a more clear dose–response relationship according to the results of lysosomal stability compared to the filtration rate.
Mostrar más [+] Menos [-]Organochlorine pesticides (OCPs) in soils and sediments, southeast China: A case study in Xinghua Bay Texto completo
2011
Zhang, Jiaquan | Qi, Shihua | Xing, Xinli | Tan, Lingzhi | Gong, Xiangyi | Zhang, Yuan | Zhang, Junpeng
This study evaluated the contamination status and distribution of organochlorine pesticides (OCPs) between Xinghua Bay and adjacent watersheds in Putian region, southeast China. Twenty-five surface soil samples and two sediment cores were collected from two watersheds and the Xinghua Bay, respectively. Results showed that the concentrations of OCPs in samples of the Mulan River Watershed (MRW), the Qiulu River Watershed (QRW), the inner bay core (IBC) and the open bay core (OBC) were in the range of 4.96–38.20ng/g, 4.62–22.80ng/g, 1.84–80.46ng/g and 1.87–23.43ng/g, respectively. The mean concentration of OCPs was in an order: IBC>MRW>QRW>OBC. The higher concentration of OCPs in recent periods may suggest that a certain amount of OCPs were still input to this area.
Mostrar más [+] Menos [-]Assessment of phosphogypsum impact on the salt-marshes of the Tinto river (SW Spain): Role of natural attenuation processes Texto completo
2011
Pérez López, Rafael | Castillo, Julio | Sarmiento, Aguasanta M. | Nieto, José M.
About 120Mton of phosphogypsum from the fertiliser industry were stack-piled on the salt-marshes of the Tinto river (Spain). This paper investigates the capacity of salt-marshes to attenuate contamination due to downward leaching from phosphogypsum. Solids and pore-waters were characterized at different depths of the pile to reach the marsh-ground. In superficial zones, metals were highly mobile, and no reduced sulphur was found. However, pollutant concentration decreased in the pore-water in deeper oxygen-restricted zones. Metal removal occurred by precipitation of newly formed sulphides, being this process main responsible for the contamination attenuation. Pyrite-S was the main sulphide component (up to 2528mg/kg) and occurred as framboids, leading to high degrees of pyritization (up to 97%). The sulphidization reaction is Fe-limited; however, excess of acid-volatile sulphide over other metals cause precipitation of other sulphides, mainly of Cu and As. This decrease in metal mobility significantly minimises the impact of phosphogypsums on the salt-marshes.
Mostrar más [+] Menos [-]Light-induced bird strikes on vessels in Southwest Greenland Texto completo
2011
Merkel, Flemming Ravn | Johansen, Kasper Lambert
Light-induced bird strikes are known to occur when vessels navigate during darkness in icy waters using powerful searchlight. In Southwest Greenland, which is important internationally for wintering seabirds, we collected reports of incidents of bird strikes over 2–3 winters (2006–2009) from navy vessels, cargo vessels and trawlers (total n=19). Forty-one incidents were reported: mainly close to land (<4km, 78%), but one as far offshore as 205km. Up to 88 birds were reported killed in a single incident. All occurred between 5p.m. and 6a.m. and significantly more birds were involved when visibility was poor (snow) rather than moderate or good. Among five seabird species reported, the common eider (Somateria mollissima) accounted for 95% of the bird casualties. Based on spatial analyses of data on vessel traffic intensity and common eider density we are able to predict areas with high risk of bird strikes in Southwest Greenland.
Mostrar más [+] Menos [-]Increased plastic litter cover affects the foraging activity of the sandy intertidal gastropod Nassarius pullus Texto completo
2011
Aloy, Alexander B. | Vallejo, Benjamin M., Jr | Juinio-Meñez, Marie Antonette
This study analyzed the foraging behavior of the gastropod Nassarius pullus on garbage-impacted sandy shores of Talim Bay, Batangas, Philippines. The effect of different levels of plastic garbage cover on foraging efficiency was investigated. Controlled in situ baiting experiments were conducted to quantify aspects of foraging behavior as affected by the levels of plastic litter cover in the foraging area. The results of the study indicated that the gastropod’s efficiency in locating and in moving towards a food item generally decreased as the level of plastic cover increased. Prolonged food searching time and increased self-burial in sand were highly correlated with increased plastic cover. The accuracy of orientation towards the actual position of the bait decreased significantly when the amount of plastic cover increased to 50%. These results are consistent with the significant decreases in the abundance of the gastropod observed during periods of deposition of large amounts of plastic and other debris on the shore.
Mostrar más [+] Menos [-]Effects of nutrient enrichment on macroalgal coralligenous assemblages Texto completo
2011
Piazzi, Luigi | Gennaro, Paola | Balata, David
Effects of eutrophication on marine ecosystems have been widely studied, even if both the effects on deep subtidal rocky assemblages and response of different successional stages to nutrients impact are still not clear. In this context, the study aimed to evaluate the effects of nutrient enrichment on Mediterranean macroalgal assemblages associated with coralligenous habitat. A manipulative field experiment was carried out by supplying both mature and early successional stages of assemblages with nutrients. A total of 62 macroalgal species were identified. Multivariate and univariate analyses showed that the structure of both mature and early successional macroalgal assemblages of coralligenous significantly varied between areas treated with nutrients and not treated areas. Moreover, differences were stronger when macroalgal assemblages were in the early successional stage than in the mature one. Results highlighted the role played by nutrients in determining the structure of macroalgal coralligenous assemblages, furthermore suggesting possible synergetic effects with other kinds of disturbances.
Mostrar más [+] Menos [-]Richards Bay Harbour: Metal exposure monitoring over the last 34years Texto completo
2011
Greenfield, R. | Wepener, V. | Degger, N. | Brink, K.
Richards Bay Harbour is South Africa’s premier bulk cargo port. It was constructed in the Mhlathuze estuary in 1976 and over the past 34years has become South Africa’s most modern and largest cargo handling port. Although no official monitoring programme is in progress various studies by different groups have provided relevant data with respect to changing metal levels in brown mussel tissue (Perna perna) over the last 34years. Eleven elements were analysed in brown mussels from the main channel in Richards Bay Harbour using ICP-MS. The results indicate that the metal concentrations in the mussel tissue remained relatively constant between 1974 and 2005. The mean metal concentrations increased significantly in 2005 possibly due to the construction of the new coal terminal and associated dredging activities. Mean metal concentrations in the 2008 sampling event were also elevated due to increased run off during an above average rainy season.
Mostrar más [+] Menos [-]In situ biomonitoring of caged, juvenile Chinook salmon (Oncorhynchus tshawytscha) in the Lower Duwamish Waterway Texto completo
2011
Kelley, Matthew A. | Gillespie, Annika | Zhou, Guo-Dong | Zhang, Shu | Meador, James P. | Duncan, Bruce | Donnelly, K. C. | McDonald, Thomas J.
Contaminated sediments may have wide-ranging impacts on human and ecological health. A series of in situ caged exposure studies using juvenile Chinook salmon was conducted in the Lower Duwamish Waterway (LDW). Chemical analysis of sediment, water, and fish tissue were completed. Additionally, in 2004, DNA adducts in hepatic and gill tissues were measured. Gills contained significantly higher DNA adducts at stations B2 and B4, prompting further analysis of gills in 2006 and 2007. Fluorescent aromatic compounds (FACs) in bile, and CYP1A1 in hepatic tissue were also measured during 2006 and 2007, respectively. FACs in field-caged fish were comparable or significantly higher than wild-caught fish LDW fish and significantly higher than lab fish after only 8–10days, demonstrating the equivalency of exposure to that of migrating salmon. Furthermore, selected biomarkers appear to be capable of detecting spikes in contamination between sampling years, emphasizing the need for multiple year data collection.
Mostrar más [+] Menos [-]Seabirds and chronic oil pollution: Self-cleaning properties of gulls, Laridae, as revealed from colour-ring sightings Texto completo
2011
(C.J.) Camphuysen, Kees
Mystery oil spills off the Dutch coast affected colonial, adult Lesser Black-backed Gulls prior to and within the breeding season. From colour-ringed individuals, it was demonstrated that most oiled birds survived and were clean within a few weeks and often bred successfully. Further evidence of self-cleaning properties of Larus-gulls is provided from a long-term colour-ringing project (1984–2009). In total 46 birds were reported ‘oiled’, two died, but the majority cleaned itself and survived for up to 20years after being oiled. From colour-ring data and 30years of beached bird surveys (1980–2010) it is demonstrated that the effects of chronic oil pollution is larger in winter than in summer; a reflection of seasonal differences in exposure and environmental conditions. The self-cleaning properties of gulls are such that long-term survival is not necessarily jeopardised and even in a breeding season, not all is lost in case of a spill.
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