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1.
A preliminary survey of seven trace metals in three species of oyster from the Knysna estuary, South Africa, has been carried out. The results which were obtained indicate that this area is as yet unpolluted and provide base-line levels against which future trace-metal pollution can be measured. Two species of oyster are being grown at a number of sites as part of a long-term programme to monitor trace-metal levels in the estuary.  相似文献   

2.
Over the last three decades there has been a significant decline in the number of marine pollution monitoring-related studies in South Africa. Thus, the current study was conducted to assess the current state of metal contamination within the South African marine environment through the validation of the artificial mussel (AM). Indigenous reference mussels (Perna perna) were deployed alongside the passive device within the South African marine environment for a 6 week exposure period. Analysis of metal uptake (Cd, Cr, Cu, Pb and Zn) was determined by filtration and elution of the AM chelex resins, microwave digestion of the transplanted mussels, and determination of their metal concentrations by ICP-MS and ICP-OES analysis. Uptake patterns between the AM and transplanted mussels showed significant temporal and spatial correlation for the majority of the elements analysed. While the AM provided relevant and complementary information on the dissolved metal concentrations, limitations were also observed.  相似文献   

3.
The artificial mussel (AM), a novel chemical sampling device, has been developed for monitoring dissolved trace metals in marine environments. The AM consists of Chelex-100 suspended in artificial seawater within Perspex tubing and enclosed with semi-permeable polyacrylamide gel at both ends. To validate the field performance of the AM in temperate waters, we deployed AMs alongside transplanted blue mussels Mytilus edulis in coastal environments in Scotland (Holy Loch, Loch Fyne, Loch Striven and Millport) and Iceland (Reykjavikurh?fn, Gufunes, South of thornerney, Hofsvik, Hvalfj?rethur and Sandgerethi) for monitoring trace metals. While uptake patterns of Cd between the AM and M. edulis were highly comparable, discrepancies were found in the accumulation profiles of the other metals (Cu, Cr, Pb and Zn), in particular Zn. Nonetheless, the AMs gave a better resolution to accurately reveal the spatial difference in dissolved metal contamination when compared with M. edulis. AMs complement the use of mussels since AMs indicate dissolved metals in seawater, whereas uptake by mussels indicates a mixture of dissolved and particulate metals. Our results also indicated that historical metal exposure of the transplanted M. edulis could significantly confound their metal concentrations especially when the deployment period was short (i.e. <34d). This study suggested that the AM can overcome problems associated with variable biological attributes and pre-exposure history in the mussel, and provides a standardized and representative time-integrated estimate of dissolved metal concentrations in different marine environments.  相似文献   

4.
Employing clean and quantitative techniques, a marine monitoring programme succeeded in detecting large surface elevations in the concentrations of dissolved Cu, Zn and Pb in the marine surface waters of Puget Sound adjacent to Seattle and Tacoma, Washington. Physical mixing with cleaner waters was the controlling factor in reducing the dissolved concentrations of Cu downstream of these contaminated regions. Comparisons between Puget Sound waters and coastal waters adjacent to Puget Sound suggest that a portion of this Cu, Zn and Pb pollution is being advected out of Puget Sound. The low Ni and Cd concentrations found in this study indicate that these trace metals are not a significant pollution problem in the main basin of Puget Sound.  相似文献   

5.
《Marine pollution bulletin》2012,64(5-12):108-118
Over the last three decades there has been a significant decline in the number of marine pollution monitoring-related studies in South Africa. Thus, the current study was conducted to assess the current state of metal contamination within the South African marine environment through the validation of the artificial mussel (AM). Indigenous reference mussels (Perna perna) were deployed alongside the passive device within the South African marine environment for a 6 week exposure period. Analysis of metal uptake (Cd, Cr, Cu, Pb and Zn) was determined by filtration and elution of the AM chelex resins, microwave digestion of the transplanted mussels, and determination of their metal concentrations by ICP-MS and ICP-OES analysis. Uptake patterns between the AM and transplanted mussels showed significant temporal and spatial correlation for the majority of the elements analysed. While the AM provided relevant and complementary information on the dissolved metal concentrations, limitations were also observed.  相似文献   

6.
Biological monitoring of marine contaminants often involves the analysis of metals accumulated in mussel tissues. Critiques of this type of monitoring suggest that although relatively good indications of ambient metal concentrations are determined, actual biological harm is not elucidated. Biomarkers, techniques originally developed in medicine, have recently been employed in an attempt to ascertain the health of marine mussels. Biomarkers have been used with good effect in temperate marine pollution monitoring programmes. The use of biomarkers in the toxicological evaluation of tropical and subtropical waters is, however, generally lacking, which is somewhat surprising, as considerable industrialisation and environmental degradation is taking place in the Pacific-rim countries of Southeast Asia. In the present study, a suite of cytological and physiological biomarkers have been measured from mussels (Perna viridis: Mytilidae) transplanted within the coastal waters of Hong Kong. Mussels from contaminated sites, had labile lysosomal membranes, whereas animals from a cleaner reference site had more stable membranes. These cytological responses have been related to metal-induced stress and are simple, cost-effective markers of pollution. Cardiac activity from mussels transplanted to polluted sites was generally similar to that of individuals from the reference site, although a mild tachycardia was associated with one site. The cause of the tachycardia and the use of heart rate in mussels as a biomarker is discussed. Integrated physiological responses to stress, condition indices, revealed mussels from a clean reference site had higher indices than animals from contaminated sites. The relative sensitivities of the cytological and physiological biomarkers deployed in this study and their application to pollution monitoring is discussed.  相似文献   

7.
《Marine pollution bulletin》2012,65(12):2756-2760
Polyethylene pellets provide a convenient means to monitor Persistent Organic Pollutants (POPs) in marine systems. Pellets collected between 1984 and 2008 at three South African beaches were analysed for PCB, HCH and DDT. Concentrations of all three POPs decreased over the last two decades, although this signal was less clear for PCBs, and further monitoring is needed to assess trends in this family of compounds. DDT concentrations at two sites were higher than previous records for southern Africa, but there is no evidence of a link to the ongoing use of DDT for malaria control. HCHs concentrations were lower than in pellets from the east coast of southern Africa, suggesting that this pesticide was mainly used in the eastern part of the region. Our study demonstrates the potential for International Pellet Watch to track temporal as well as geographical patterns in the abundance of POPs in marine environments.  相似文献   

8.
There has been growing speculation to what extent marine animals may gather where physical processes lead to a concentration of food in the vicinity of marine fronts. It appears that at a front off western South America only plankton-eating birds gathered at the front itself, though fish-eating species were most numerous in its general vicinity. Drifting garbage also accumulated at the front, which arrested its spread but may pose a threat to the birds from pollution.  相似文献   

9.
《Marine pollution bulletin》2009,58(6-12):790-800
The artificial mussel (AM), a novel chemical sampling device, has been developed for monitoring dissolved trace metals in marine environments. The AM consists of Chelex-100 suspended in artificial seawater within Perspex tubing and enclosed with semi-permeable polyacrylamide gel at both ends. To validate the field performance of the AM in temperate waters, we deployed AMs alongside transplanted blue mussels Mytilus edulis in coastal environments in Scotland (Holy Loch, Loch Fyne, Loch Striven and Millport) and Iceland (Reykjavikurhöfn, Gufunes, South of þerney, Hofsvik, Hvalfjörður and Sandgerði) for monitoring trace metals. While uptake patterns of Cd between the AM and M. edulis were highly comparable, discrepancies were found in the accumulation profiles of the other metals (Cu, Cr, Pb and Zn), in particular Zn. Nonetheless, the AMs gave a better resolution to accurately reveal the spatial difference in dissolved metal contamination when compared with M. edulis. AMs complement the use of mussels since AMs indicate dissolved metals in seawater, whereas uptake by mussels indicates a mixture of dissolved and particulate metals. Our results also indicated that historical metal exposure of the transplanted M. edulis could significantly confound their metal concentrations especially when the deployment period was short (i.e. <34 d). This study suggested that the AM can overcome problems associated with variable biological attributes and pre-exposure history in the mussel, and provides a standardized and representative time-integrated estimate of dissolved metal concentrations in different marine environments.  相似文献   

10.
Past monitoring of heavy metals, organochlorine compounds and polyaromatic hydrocarbons (PAHs) has found that pollutant concentrations are generally low within the Great Barrier Reef Marine Park and World Heritage Area and are indicative of a relatively unpolluted environment. The exceptions are sites that are adjacent to human activity such as ports and harbours, urban centres and areas adjacent to intensive agricultural activity. These sites have elevated concentrations of a range of pollutants. Concentrations of dioxins have also been found to be elevated in marine park sediments. Elevated pollutant concentrations are generally the consequence of effluent discharge, urban stormwater, and agricultural and industrial runoff. However, a majority of Great Barrier Reef pollutant data are now dated, and contemporary information is required concerning the distribution and impact of pollutants in the Queensland marine environment. The utility of specialized monitoring tools such as biomarkers for tropical marine environments urgently needs to be examined. With this information, appropriate risk assessment and monitoring can be implemented and effective management strategies developed to protect tropical marine ecosystems including the Great Barrier Reef.  相似文献   

11.
Due to their close proximity to the point sources of pollution, estuaries and harbours are exposed to metals. Mussels are used worldwide to monitor marine pollution due to their ability to take up contaminants and the ease of transplantation. Mussels were collected from two reference sites and transplanted in Richards Bay Harbour (2006 and 2010) and in three harbours. Transplanted and resident mussels were removed after 6 weeks exposure and metal concentrations were analysed using ICP-MS techniques. Transplanted mussels had higher metal concentrations than the resident mussels. This was attributed to regulation of metals by the resident mussels. Metal regulation was greater in mussels that are continuously submerged as opposed to those that undergo tidal influences. For monitoring it is essential that the reference population for transplantation is considered carefully as upwelling events in the pristine reference location results in significant increases in metal bioaccumulation.  相似文献   

12.
Data on water quality, sediment quality and aquatic organisms in Port Kembla Harbour from the 1970s to the 1990s are reviewed. In the 1970s, the marine environment of Port Kembla Harbour was in poor condition as a result of pollution from heavy industries. Elevated concentrations of pollutants were found in water, sediment and fish in the harbour; aquatic biodiversity was limited and many fish kills were reported. With the implementation of pollution reduction programs (required by legislation changes) by the industries surrounding the harbour since the 1970s, pollution in the harbour has been reduced dramatically, and the quality of the marine environment of the harbour has noticeably improved. Large reductions in the concentrations of certain toxic wastes and heavy metals in water have occurred. Marine life has returned to the whole harbour (parts were described in 1977 as abiotic). Contaminants in fish have decreased. Despite this achievement, however, there is still considerable room for improvement in the quality of the marine environment of the harbour.  相似文献   

13.
Mussels are used as sentinel organisms and bioindicators to evaluate the toxic effects of chemical pollutants in marine organisms, especially heavy metals, representing an important tool for biomonitoring environmental pollution in coastal areas. Antioxidant defence enzymes play an important role in cellular antioxidant defence systems and protect from oxidative damage by reactive oxygen species (ROS). Indigenous mussels Mytilus galloprovincialis of the Saronikos Gulf of Greece were used for monitoring heavy metal pollution in three polluted sites in the area and in one unpolluted site. Seasonal variations of the activity of antioxidant defence enzymes, superoxide dismutase (SOD) and catalase (CAT), as well as lipid peroxidation (LP) were measured as biomarkers in a period of three years in relation to concentrations of trace metals in their gills and mantle and compared to mussels from an unpolluted sampling site. SOD activity increased at least 2 fold at the polluted sites when compared to the control site (the high activity was recorded in the spring time). CAT activity was increased 2-3 times at the polluted sites, with high activity in the winter and spring time, compared to the control site. LP concentration was twice higher at the polluted sites, following the same seasonal pattern. Trace metals contents in mussels collected at polluted sites were 3-4 fold higher compared to the control site and showed moderate variations along the months, with a winter maximum followed by a summer pre-spawning minimum matching the seasonal trends of temperature and salinity. Our results showed that metal pollution in the Elefsis Bay (the most polluted coastal area) causes relatively medium levels of oxidative stress in tissues of mussels due to cellular oxy-radical generation. This study, which is the first in the area, showed that seasonal variations of the activity of antioxidant defence enzymes and LP concentrations in mussels can be used as potential biomarkers of toxicity for long-term monitoring in marine coastal ecosystems.  相似文献   

14.
大通湖及东洞庭湖区生物体重金属的水平及其生态评价   总被引:4,自引:0,他引:4  
于2005年11月采集了大通湖及东洞庭湖区湖水和水生生物样品,并测定了水和水生生物样品中重金属(Cd、Pb、Hg、As)的含量,并对湖区生物体重金属进行了污染评价.研究结果表明,大通湖及东洞庭湖区湖水中重金属含量较小,绝大部分采样点水质都属于国家Ⅰ类水标准;水生生物体内CD、Pb含量为虾>螺>鱼,Hg的含量为鱼>螺>虾,As的含量为螺>虾>鱼;而鱼类重金属含量则为底栖鱼类>中上层鱼类,肉食性鱼类>植食性鱼类.大通湖及东洞庭湖区生物体中CD、Pb的污染指数为虾>螺>鱼,Hg的污染指数则为鱼>螺>虾,As的污染指数则为螺>虾>鱼.  相似文献   

15.
In this study, the bioremediation potentials of two seaweeds (Sargassum hemiphyllum and S. henslowianum) against pollution in a coastal mariculture area of Shenzhen, South China, were investigated by comparing the growth, nutrient bioaccumulation capacity of plants from the seaweed bed (control site) with plants from the fish farm. Results indicated that both species are potential candidates for bioremediation in the fish farm areas in terms of their high growth rates and high bioaccumulation capacities on inorganic nutrients. Both Sargassum spp. contain high levels of crude protein (11.7–14.0%) and crude fat (2.2–2.7%), suggesting high nutritional values. The S. hemiphyllum may serve as a good aquaculture fodder with high nutritional compositions and low heavy metal contents. However, heavy metals (Cr, Pb and Cd) of S. henslowianum exceed the maximum allowable concentrations as aquatic feed, which restricts its fodder application. In general, the results of this study may contribute to the marine pollution bioremediation in the coastal areas of South China, especially in mariculture zones.  相似文献   

16.
Samples of marine benthic invertebrates collected from two sites in the Antarctic have been analysed for both aliphatic and aromatic hydrocarbons in order to establish baseline concentrations for some classes of hydrocarbons.Samples from Signy Island, a pristine site, contained low concentrations of the hydrocarbons determined, whereas those from King Edward Cove, South Georgia, contained significantly higher concentrations. King Edward Cove has a known history of pollution from whaling operations.Platt & Mackie (1979) have suggested that the hydrocarbons in sediments from King Edward Cove are a result of the world-wide dissemination of the pyrolysis products of fossil fuels. Our work suggests, in contrast, that the hydrocarbons in the benthos are derived from local sources.  相似文献   

17.
Preferred characteristics of biological indicators for heavy metal monitoring in marine ecosystems were documented 30 years ago. Heavy metal data from Raine Island on the outer-northern Great Barrier Reef are presented to introduce additional attributes for consideration, including a widened choice of biological tissues due to advances in trace heavy metal analysis. Kidney tissues, visceral mass and adductor muscle from the giant clam (Tridacna maxima), muscle tissue from trochus (Trochus niloticus) and axial muscle from four species of fish were targeted. The kidneys of giant clams had concentrations of heavy metals from 2 (Zn) to 2780 (Ni) times higher than corresponding concentrations in adductor muscles. Also, tissues of giant clam and the muscle of trochus gave different signals with respect to bio-available heavy metals. Linear correlations for heavy metals within and between tissues of giant clam and within muscle tissue of trochus, offer opportunities for the use of surrogates as well as a possible mathematical basis for assessing trends in heavy metal pollution.  相似文献   

18.
Egypt is located in the Northeast of Africa where oil and gas (O&G) are produced offshore from the Gulf of Suez and the Southeast part of the Mediterranean. The O&G production in Egypt is distributed as follows: 70% from Gulf of Suez, 16% from Western desert, 8% from the Sinai Peninsula and 6% from Eastern desert. Past O&G activities, refining and transport have resulted in chronic pollution in Egyptian offshore and numerous environmental programs have been initiated to protect new development areas from the environmental impacts. The offshore drilling process uses drilling fluids (mud) and generates waste fluids and cuttings, which could be the largest discharges going into the receiving water bodies. There are several options to manage offshore drilling wastes: offshore discharge, offshore down-hole injection and onshore disposal. Water-based drilling fluids (WBF) are commonly employed for drilling in Egyptian offshore because of their expected environmental benign behavior. The main objective of this paper is to develop a methodology to determine the fate of heavy metals associated with WBF drilling waste in the marine environment and estimate the associated ecological risks. Proposed contaminant fate model is based on an aquivalence approach, which has been integrated with fuzzy-based analysis to study the uncertainties. This research concluded that the impacts of heavy metals associated with the drilling waste discharges in the receiving waters are minimal.  相似文献   

19.
Monitoring of toxic substances in the Hong Kong marine environment   总被引:1,自引:0,他引:1  
A long-term programme for monitoring toxic substances in the marine environment was established in Hong Kong in 2004, focusing on chemicals of potential ecological and health concern. The programme ran on 3-year cycles, with the first two years monitoring marine water, sediment, biota, and the third year monitoring pollution sources. Twenty-four priority chemicals were measured, including dioxins/furans, dioxin-like PCBs, total PCBs, PAHs, DDTs, HCHs, TBTs, phenol, nonylphenol (NP), NP ethoxylates, PBDEs and metals. Results from the first three years of monitoring indicate that toxic substances in the Hong Kong marine environment were within the range reported for the coastal waters in China and other regions, but generally lower than in the Pearl River Estuary. The levels met the standards for protecting aquatic life and human consumption. Sewage effluent, stormwater and river water were possible sources of phenolic compounds; whereas air deposition or regional pollution, rather than local discharges, may contribute to the dioxins/furans, PAHs and PCBs found in the marine environment.  相似文献   

20.
Trace metal concentrations in the waters of the Gulf of St. Lawrence and the Scotian Shelf and their sensitivity to changes in the composition of the major contributor of fresh water, the St. Lawrence River, are assessed. Comparison of the levels of trace metals in eastern Canadian coastal waters with those in other coastal waters of the world reveals that the former area generally has lower trace metal concentrations and is, therefore, probably less contaminated than elsewhere. The increased anthropogenic activity in the St. Lawrence drainage basin required to increase the levels of trace metals in receiving coastal waters by detectable amounts is discussed. We demonstrate that faster and more reliable warning of changes due to anthropogenic activity will be revealed through river monitoring than through monitoring of coastal waters. Changes in the marine environment can then be assessed through a thorough understanding of the geochemical behaviour of trace metals in nearshore waters.  相似文献   

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