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A simple osmium post-fixation paraffin-embedment technique to identify lipid accumulation in fish liver using medaka (Oryziaslatipes) eggs and eleutheroembryos as lipid rich models Texto completo
2011
Mondon, J.A. | Howitt, J. | Tosiano, M. | Kwok, K.W.H. | Hinton, D.E.
Hepatic lipidosis is a non-specific biomarker of effect from pollution exposure in fish. Fatty liver is often misdiagnosed or overlooked in histological assessments due to the decreasing application of specific fat procedures and stains. For example, ethanol dehydration in standard paraffin processing removes lipids, leaving vacuoles of which the precise nature is unknown. Lipids can be identified using osmium post-fixation in semi-thin resin sections or transmission electron microscopy. However, both are expensive and technically demanding procedures, often not available for routine environmental risk assessment and monitoring programs. The current emphasis to reduce and refine animal toxicity testing, requires refinement of the suite of histopathological techniques currently available to maximize information gained from using fish for toxicity testing and as bio-indicators of environmental quality. This investigation has successfully modified an osmium post-fixation technique to conserve lipids in paraffin-embedded tissues using medaka (Oryzias latipes) eleutheroembryos and eggs (embryos) as lipid rich models.
Mostrar más [+] Menos [-]Brown mussels (Perna perna) and semi-permeable membrane devices (SPMDs) as indicators of organic pollutants in the South African marine environment Texto completo
2011
Degger, N. | Wepener, V. | Richardson, B.J. | Wu, R.S.S.
A distinct lack of historical and current data on the status of organic pollutant contaminants within the South African marine environment is evident. This has highlighted the need for more current organic pollutant assessments. Reference mussels and SPMDs were transplanted at five South African harbour sites to assess organic bioaccumulation in brown mussels (Perna perna) and semi-permeable membrane devices (SPMDs). Spatial patterns of PAH and PCB contaminants were determined by GC–MS and GC–ECD after appropriate sample preparation. Significant (p<0.05) spatial differences were observed between the sites. Results indicate no correlations between the passive device and the transplanted mussels; however the SPMDs provided complementary information on the presence of dioxin-like PCBs within the environment not detected by the mussel. The results indicate that information provided by both the mussels and SPMDs allow for a more in depth scrutiny of environmental conditions as a result of anthropogenic influence.
Mostrar más [+] Menos [-]Accumulation of trace elements in harp seals (Phoca groenlandica) from Pangnirtung in the Baffin Island, Canada Texto completo
2011
Agusa, Tetsuro | Nomura, Kumiko | Kunito, Takashi | Anan, Yasumi | Iwata, Hisato | Tanabe, Shinsuke
Nineteen trace elements were determined in liver, muscle, kidney, gonads, and hair of 18 harp seals (Phoca groenlandica) from Pangnirtung in the Baffin Island, Canada. Concentrations of V, Mn, Fe, Cu, Mo, Ag, and Hg in the liver, Co, Cd, and Tl in the kidney, and Ba and Pb in the hair were significantly higher than those in other tissues. Significant positive correlations between Hg concentrations in the hair, and liver, kidney and testis imply usefulness of the hair sample for non-destructive monitoring of Hg in the harp seals. It is suggested that whereas Hg preferentially accumulates in the liver, the accumulation in other tissues is induced at higher hepatic Hg levels. In contrast, Se may not be accumulated in other tissues compared with the liver even at higher hepatic Hg levels because of the presence of excess Se for Hg detoxification in other tissues.
Mostrar más [+] Menos [-]Trace metals in sediment cores from Deception and Penguin Islands (South Shetland Islands, Antarctica) Texto completo
2011
Guerra, Roberta | Fetter, Eva | Ceschim, Liziane M.M. | Martins, César C.
This paper presents information on the levels of trace elements in sediments collected at Deception and Penguin Islands and tracks the sources of natural and anthropogenic inputs of metals into this sub-Antarctic region. The results suggest that natural processes, such as volcanic activity, hydrothermal processes and sediment transport, are more important than anthropogenic inputs in accounting for the metal concentrations measured in sediments at Deception Island. The higher levels of trace metals recorded in sediments at Penguin Island seem to reflect the composition of the source rocks of the island, which are dominated by the olivine-basalt group. Our findings show that human activities in the study areas may contribute to negligible levels of trace metals associated with anthropogenic inputs (e.g., Cr and Zn) in sediments, and these results can be used in the future as background levels related to low anthropogenic impacts.
Mostrar más [+] Menos [-]The use of kelp sieve tube sap metal composition to characterize urban runoff in southern California coastal waters Texto completo
2011
Fink, Laurel A. | Manley, Steven L.
This study introduces an innovative method for biomonitoring using giant kelp (Macrocystis pyrifera) sieve tube sap (STS) metal concentrations as an indication of pollution influence. STS was sampled from fronds collected from 10 southern California locations, including two reference sites on Santa Catalina Island. Using ICP-MS methodology, STS concentrations of 17 different metals were measured (n=495). Several metals associated with pollution showed the highest STS concentrations and most seasonal variation from populations inside the Port of Los Angeles/Long Beach. Lowest concentrations were measured at less-urbanized areas: Santa Catalina Island and Malibu. Some metals showed a spatial gradient in STS metal concentration with increasing distance from point sources (i.e. Los Angeles River). Cluster analyses indicate that polluted seawater may affect kelp uptake of metals essential for cellular function. Results show that this method can be useful in describing bioavailable metal pollution with implications for accumulation within an important ecosystem.
Mostrar más [+] Menos [-]Recommendations on methods for the detection and control of biological pollution in marine coastal waters Texto completo
2011
Olenin, Sergej | Elliott, Michael | Bysveen, Ingrid | Culverhouse, Phil F. | Daunys, Darius | Dubelaar, George B.J. | Gollasch, Stephan | Goulletquer, Philippe | Jelmert, Anders | Kantor, Yuri | Mézeth, Kjersti Bringsvor | Minchin, Dan | Occhipinti, Anna | Olenina, Irina | Vandekerkhove, Jochen
Recommendations on methods for the detection and control of biological pollution in marine coastal waters Texto completo
2011
Olenin, Sergej | Elliott, Michael | Bysveen, Ingrid | Culverhouse, Phil F. | Daunys, Darius | Dubelaar, George B.J. | Gollasch, Stephan | Goulletquer, Philippe | Jelmert, Anders | Kantor, Yuri | Mézeth, Kjersti Bringsvor | Minchin, Dan | Occhipinti, Anna | Olenina, Irina | Vandekerkhove, Jochen
Adverse effects of invasive alien species (IAS), or biological pollution, is an increasing problem in marine coastal waters, which remains high on the environmental management agenda. All maritime countries need to assess the size of this problem and consider effective mechanisms to prevent introductions, and if necessary and where possible to monitor, contain, control or eradicate the introduced impacting organisms. Despite this, and in contrast to more enclosed water bodies, the openness of marine systems indicates that once species are in an area then eradication is usually impossible. Most institutions in countries are aware of the problem and have sufficient governance in place for management. However, there is still a general lack of commitment and concerted action plans are needed to address this problem. This paper provides recommendations resulting from an international workshop based upon a large amount of experience relating to the assessment and control of biopollution.
Mostrar más [+] Menos [-]Recommendations on methods for the detection and control of biological pollution in marine coastal waters Texto completo
2011
Olenin, Sergej | Elliott, Michael | Bysveen, Ingrid | Culverhouse, Phil F. | Daunys, Darius | Dubelaar, George B.J. | Gollasch, Stephan | Goulletquer, Philippe | Jelmert, Anders | Kantor, Yuri | Mézeth, Kjersti Bringsvor | Minchin, Dan | Occhipinti-Ambrogi, Anna | Olenina, Irina | Vandekerkhove, Jochen
Adverse effects of invasive alien species (IAS), or biological pollution, is an increasing problem in marine coastal waters, which remains high on the environmental management agenda. All maritime countries need to assess the size of this problem and consider effective mechanisms to prevent introductions, and if necessary and where possible to monitor, contain, control or eradicate the introduced impacting organisms. Despite this, and in contrast to more enclosed water bodies, the openness of marine systems indicates that once species are in an area then eradication is usually impossible. Most institutions in countries are aware of the problem and have sufficient governance in place for management. However, there is still a general lack of commitment and concerted action plans are needed to address this problem. This paper provides recommendations resulting from an international workshop based upon a large amount of experience relating to the assessment and control of biopollution.
Mostrar más [+] Menos [-]Recommendations on methods for the detection and control of biological pollution in marine coastal waters Texto completo
2011
Olenin, Sergej | Elliott, Michael | Bysveen, Ingrid | Culverhouse, Phil F. | Daunys, Darius | Dubelaar, George B. J. | Gollasch, Stephan | Goulletquer, Philippe | Jelmert, Anders | Kantor, Yuri | Mezeth, Kjersti Bringsvor | Minchin, Dan | Occhipinti-ambrogi, Anna | Olenina, Irina | Vandekerkhove, Jochen
Adverse effects of invasive alien species (IAS), or biological pollution, is an increasing problem in marine coastal waters, which remains high on the environmental management agenda. All maritime countries need to assess the size of this problem and consider effective mechanisms to prevent introductions, and if necessary and where possible to monitor, contain, control or eradicate the introduced impacting organisms. Despite this, and in contrast to more enclosed water bodies, the openness of marine systems indicates that once species are in an area then eradication is usually impossible. Most institutions in countries are aware of the problem and have sufficient governance in place for management. However, there is still a general lack of commitment and concerted action plans are needed to address this problem. This paper provides recommendations resulting from an international workshop based upon a large amount of experience relating to the assessment and control of biopollution. Highlights ► We summarize the results of an international workshop on marine biopollution. ► We recommend science-based information support for bioinvasion management. ► We outline types of bioinvasion monitoring and consider topical research needs. ► We emphasize the role of taxonomy training and public involvement. ► Biopollution should be treated in the same way as any other type of pollution.
Mostrar más [+] Menos [-]Recommendations on methods for the detection and control of biological pollution in marine coastal waters Texto completo
2011
Adverse effects of invasive alien species (IAS), or biological pollution, is an increasing problem in marine coastal waters, which remains high on the environmental management agenda. All maritime countries need to assess the size of this problem and consider effective mechanisms to prevent introductions, and if necessary and where possible to monitor, contain, control or eradicate the introduced impacting organisms. Despite this, and in contrast to more enclosed water bodies, the openness of marine systems indicates that once species are in an area then eradication is usually impossible. Most institutions in countries are aware of the problem and have sufficient governance in place for management. However, there is still a general lack of commitment and concerted action plans are needed to address this problem. This paper provides recommendations resulting from an international workshop based upon a large amount of experience relating to the assessment and control of biopollution.
Mostrar más [+] Menos [-]Polychaete/amphipod ratio as an indicator of environmental impact related to offshore oil and gas production along the Norwegian continental shelf Texto completo
2011
Andrade, Héctor | Renaud, Paul E.
Benthic faunal data is regularly collected worldwide to assess the ecological quality of marine environments. Recently, there has been renewed interest in developing biological indices able to identify environmental status and potential anthropogenic impacts. In this paper we evaluate the performance of a general polychaete/amphipod ratio along the Norwegian continental shelf as an environmental indicator for offshore oil and gas impacts. Two main trends are apparent: first, a contamination gradient is discernible from where production takes place compared to stations 10,000m away. Second, the quality of the marine environment has improved over time. These results are consistent with monitoring reports employing a combination of uni- and multi-variate statistics. Thus, we consider this ratio as a relatively simple, useful and potentially cost-effective complement to other more demanding assessment techniques. Because of its strong theoretical basis, it may also be useful for detecting ecological change as a result of other activities.
Mostrar más [+] Menos [-]Hollow fiber liquid-phase microextraction as clean-up step for the determination of organophosphorus pesticides residues in fish tissue by gas chromatography coupled with mass spectrometry Texto completo
2011
Sun, Xiaojin | Zhu, Fang | Xi, Jiabin | Lu, Tongbu | Liu, Hong | Tong, Yexiang | Ouyang, Gangfeng
Hollow fiber liquid-phase microextraction (HF-LPME) technique was used as a clean-up procedure for the determination of organophosphorus pesticides (OPPs) in fish tissue. In this study, eight OPPs were first extracted with acetone from fish sample, the organic extract after rotatory evaporation was then redissolved with water–methanol (95:5, v/v) solution, followed by polyvinylidene difluoride (PVDF) HF-LPME. Experimental HF-LPME and other sample preparation conditions were carefully investigated and optimized. Under the optimum conditions, good linearity were observed in the range of 20–500ng/g, limits of detections (LODs) were in the range of 2.1–4.5ng/g. The repeatability and recovery of the method also showed satisfactory results. Compared with traditional sample preparation method for the determination of OPPs in fish tissue, the method developed in this study eliminated the solid phase extraction (SPE) step, simplified the sample preparation procedure and lowered the cost of analysis.
Mostrar más [+] Menos [-]Macroalgal diversity along the Baltic Sea salinity gradient challenges Remane’s species-minimum concept Texto completo
2011
Schubert, Hendrik | Feuerpfeil, Peter | Marquardt, Ronny | Telesh, Irena | Skarlato, Sergei
Remane’s species-minimum concept, which states that the lowest number of taxa occurs at the horohalinicum (5–8psu), was tested by investigating macroalgal diversity on hard substrates along the natural salinity gradient in the Baltic Sea. Field data on species occurrence and abundance were collected by SCUBA diving along 10 transects of the Finnish, Swedish and German coasts, covering a salinity range from 3.9 to 27psu. Macroalgal species numbers declined steadily with salinity, decreasing until 7.2psu was reached, but in the horohalinicum, a marked reduction of species number and a change in diversity were indicated by the Shannon index and evenness values. The non-linear decrease in macroalgal diversity at 5–8psu and the lack of increase in species numbers at salinities below 5psu imply a restricted applicability of Remane’s species-minimum concept to macroalgae.
Mostrar más [+] Menos [-]Application of entropy analysis of in situ droplet-size spectra in evaluation of oil chemical dispersion efficacy Texto completo
2011
Li, Zhengkai | Lee, Kenneth | King, Thomas | Niu, Haibo | Boufadel, Michel C. | Venosa, Albert D.
In situ droplet-size distributions were measured using a laser in situ scattering and transmissiometry (LISST-100X) particle size analyzer during the evaluation of natural and chemical dispersion efficiency of crude oils under different wave and current conditions. An entropy grouping of the in situ dispersed oil droplet-size spectra has classified the multi-modal droplet-size distributions into different groups based on similar droplet-size spectra characteristics within groups and distinction between groups. A generalized linear logistic regression model was fitted to analyze the effects of a number of factors and their interactions on the grouping of oil droplet-size spectra. The grouped results corresponded to the oil dispersion efficiency at different levels. This new method for droplet-size distribution data analysis can have significant implication in field evaluation of natural and chemical dispersion efficiency of oil.
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