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1.
Non-specific immune response of greenback flounder, Rhombosolea tapirina, exposed to contaminated marine sediments was examined. Reference sediments from Port Sorell and contaminated sediments from Deceitful Cove, Tasmania, Australia were investigated. Hatchery-reared flounder were exposed to reference sediment, contaminated sediment or contaminated sediment and diet for 6 weeks. Phagocytic capacity and lysozyme response in flounder were examined on cessation of exposure trial. Significant differences were found in phagocytic capacity and lysozyme response between treatments. Exposure to contaminated sediment, irrespective of diet or benthic disturbance elicited inhibition of phagocytic efficiency in flounder. Disturbance of contaminated sediment stimulated lysozyme activity. The immune response in flounder indicates potential immunotoxicity of sediment from Deceitful Cove.  相似文献   

2.
As part of a multinational workshop on marine environmental quality, sediments were collected from seven sites in Vancouver Harbour and analyzed for polynuclear aromatic hydrocarbons (PAHs) and organochlorines (OCs), and for trace metals. English sole were collected from five sites, and muscle was analyzed for trace metals and liver for OCs. As expected, sediment PAH and OC concentrations and tissue OC concentrations were higher at sites east of the First Narrows, compared to the outer harbor and reference sites. Sediment PAH concentrations east of the First Narrows were similar to concentrations at moderately contaminated sites in Puget Sound, south of Vancouver Harbour. In contrast, concentrations of OCs in sediments and tissue were low to moderate, even at relatively contaminated sites within Vancouver Harbour. Although several trace metals in sediments were higher than in contaminated sediments from Puget Sound, trace metals measured in fish muscle were lower.  相似文献   

3.
Abstract

Surface sediment samples (60 μm‐2 mm, and < 60 μm fractions) from the Waiwhetu Stream, Lower Hutt City, New Zealand, were leached with dilute HCl to remove the mobile heavy‐metal fraction. Cd, Cr, Cu, Pb, Zn, Al, Fe, and Mn analyses of the leachates show that sediments of the upper reaches area of the stream are generally uncontaminated. In contrast, sediments in the lower reaches area are highly contaminated, despite clean‐up measures in the late 1970s. Lead and Zn are the most significantly enriched metals with concentrations over 1000 mg kg?1 adjacent to some drains. In the polluted zone, metals originate from either upward remobilisation from underlying sediment (contaminated in the early 1960s and 70s) or more recent industrial spillages. Similar trends exhibited by Cd, Cu, Cr, Zn, Pb, and Al indicate that a proportion of the metal enrichment downstream probably results from a naturally higher clay content of sediments near the mouth of the stream. Fe and Mn show reverse trends to the other metals, indicating that a high proportion of these two metals occurs in substrate different to that of the other metals. The orange brick‐coloured sediments of the upper reaches of the stream indicate oxides upstream; the black sediments in the lower reaches indicate sulphides downstream.  相似文献   

4.
几种近海沉积物吸附137Cs的初步研究   总被引:1,自引:0,他引:1  
尹毅  刘光章 《海洋科学》1983,7(1):18-21
在对青岛近海放射性污染调查研究中发现,该海区与对照海区(石岛海区和连云港海区)海水中~(137)Cs的含量处于同一水平,而所取沉积物中~(l37)Cs的含量却存在明显差异。同  相似文献   

5.
From the distribution of dissolved and solid arsenic species in a contaminated estuarine sediment and measured rates of flux of the various arsenic species we propose an empirical model for the cycling of arsenic between sediments and water column. The chemical form of arsenic in the sediment was largely determined by the redox state of the sediment. Arsenite was the dominant dissolved and solid species in the deeper reduced sediment, and arsenate was dominant in the oxidized surface layer. Arsenite in the interstitial water diffused toward the surface layer, where it was mostly oxidized to arsenate prior to leaving the sediments. Some arsenate adsorbed to the surface sediments and produced a surface layer enriched in arsenic. Small concentrations of methyl and dimethyl arsenic were produced in the sediments, and these also diffused into the overlying water.Nereis succinea, a burrowing polychaete, affected distribution and flux of arsenic from the sediments by its production of irrigated burrows. These burrows increased both the effective surface area of the sediment and the diffusion of arsenic by a factor of five. When the relative effects of the activities of Nereis succinea and physical resuspension are compared, results indicate that although physical resuspension can produce large pulses of materials from contaminated sediments, continuous biological activity is likely to be more important in the mobilization of contaminants from sediments in many estuarine environments.  相似文献   

6.
渤海湾潮间带(大沽口)柱状沉积物中的重金属来源判别   总被引:9,自引:0,他引:9  
采用因子分析法对2003年11月采自渤海湾潮间带(大沽口)柱状沉积物中的重金属含量数据进行了分析,提取出的三个主要因子占据重金属含量样本信息量的83.69%,以此定量判别出重金属的来源方式和富集原因。并有效采用Li和Sc作为污染重金属的参照元素,以这两种元素含量比值的自然对数和目标元素与Sc的比值的自然对数做比率散点图的方法验证了因子分析所得的结论。结果表明,Cd,Zn和As以人类活动输入为主,Pb,Cr,Hg受到一定人为输入影响,但仍以环境背景贡献为主,Cu,Al,Fe,Ni以自然来源为主。  相似文献   

7.
This paper discusses the following topics related to polynuclear aromatic hydrocarbon pollution in estuaries: (1) the use of oysters (Crassostrea virginica), hard clams (Mercenaria mercenaria) and brackish water clams (Rangia cuneata) in residue monitoring; (2) the effects of elevated PAH residues on oyster condition; (3) three years of field studies relating PAH sediment contamination to abnormalities in fishes; and (4) laboratory bioassays for effects and bioconcentration modeling. Oysters, hard clams and Rangia have been shown, from 3 years of field studies, to be good monitors of pollution inputs as one proceeds along salinity gradients from 25‰ to 0·5‰. Effects of increased body burdens of PAHs are shown by a lowering of the oysters' condition index, as measured by lipid levels. Fishes inhabiting the Elizabeth River, VA, which is highly contaminated with PAHs, have abnormalities (cataracts, skin lesions, abnormal fins, etc.). These abnormalities have higher incidence in regions of the river where the sediments are more heavily contaminated. Laboratory studies utilizing contaminated sediments have reproduced some of the abnormalities observed in the field. Bioconcentration of PAHs from sediments has been studied with oysters and hard clams. Oysters generally accumulate three times the body burdens of clams exposed to the same suspensions. A faster depuration rate (k2) for clams appears to be responsible for the higher equilibrium body burden of oysters.  相似文献   

8.
This study aimed to test the performance of the amphipod Gammarus locusta (L.) in chronic sediment toxicity tests. It constitutes part of a multi-level assessment of chronic toxicity of estuarine sediments, integrating organism and population-level endpoints with biochemical markers responses. Here we account for organism and population-level effects, while biomarker responses were reported in a companion article. Five moderately contaminated sediments from Sado and Tagus estuaries were tested, comprising 3 muddy and 2 sandy sediments. These sediments either did not show acute toxicity or were diluted with control sediment as much as required to remove acute toxicity. Subsequent chronic tests consisted of 28-day exposures with survival, individual growth and reproductive traits as endpoints. Two of the muddy sediments induced higher growth rates in the amphipods, and improved reproductive traits. This was understood to be a consequence of the amount of organic matter in the sediment, which was nutritionally beneficial to the amphipods, while concurrently decreasing contaminant bioavailability. Biomarker responses did not reveal toxicant-induced stress in amphipods exposed to these sediments. One of the sandy sediments was acutely toxic at 50% dilution, but in contrast stimulated amphipod growth when diluted 75%. This was presumed to be an indication of a hormetic response. Finally the two remaining contaminated sediments showed pronounced chronic toxicity, affecting survival and reproduction. The sex ratio of survivors was highly biased towards females, and offspring production was severely impaired. The particulars of the responses of this amphipod were examined, as well as strengths versus limitations of the sediment test. This study illustrates the utility of this chronic test for toxicity assessment of contaminated estuarine sediments, with potential application all along Atlantic Europe.  相似文献   

9.
Hatchery-reared turbot (Scophthalmus maximus L.) were exposed for 3 weeks, under laboratory conditions, to sediment collected from polluted sites in Cork Harbour and a reference site at Ballymacoda, Co. Cork, Ireland. The potential of surficial sediment for inducing hepatic biomarkers was assessed at two levels of biological organisation: expression of cytochrome P450 [Western blotting analysis and 7-ethoxy-resorufin O-dealkylase (EROD), 7-benzoxy resorufin O-dealkylase (BROD), 7-methoxy resorufin O-dealkylase (MROD), 7-pentoxy-resorufin O-dealkylase (PROD) activities] and DNA integrity (Comet assay). Positive controls were generated, either by exposing turbot to cadmium chloride-spiked seawater (Comet assay) or to beta-naphthaflavone by intraperitoneal injection (cytochrome P450 induction). The induction of cytochrome P450 activity (EROD, MROD and PROD) in animals following a 7-day exposure to contaminated sediments was significantly higher than those exposed to reference site sediment and remained elevated thereafter; BROD was not induced. DNA single-strand breaks were also significantly higher following exposure to contaminated sediments throughout the experiment. Although no direct correlation between induction of alkoxyresorufin O-dealkylase activities and a particular chemical class was established, the induction of MROD and PROD activities in fish exposed to sediments containing complex contaminant mixtures, appeared to be more sensitive than conventional EROD activity assays. We conclude from the present laboratory study that S. maximus is a suitable sentinel species for the assessment of moderately contaminated sediments and therefore allows for the further development of this model for future, ecologically relevant, field studies.  相似文献   

10.
The effects of a simulated spill of sunflower oil in salt marsh sediments were compared with an experiment with linseed oil. Sunflower and linseed oil penetrated the sediments at the same rates but different adsorption of the oils onto sediment particles resulted in the establishment of anaerobic conditions at shallower depths in sediments contaminated with linseed oil than with sunflower oil. The total lipid content of sunflower oil contaminated sediments remained almost stable for 6 months, whilst only 40% of linseed oil remained in the sediment after 2 months. Numbers of culturable heterotrophic bacteria and aerobic oil degrading bacteria in muddy sediment increased rapidly in response to the presence of the oils but bacterial numbers in sandy sediments increased more slowly for sunflower oil. Changes in fatty acid composition indicate similar degradation pathways for both oils but sunflower oil degraded more slowly than linseed oil and thus has the potential for longer lasting effects in marine environments.  相似文献   

11.
Surface intertidal sediments from 35 sites in the Irish Sea have been analysed for their 238Pu and 239,240Pu activities, together with an intensive study of plutonium in sediments of the Esk Estuary (NW England). The range of plutonium activities for the whole survey were 0·14–4118 and 1·3–16 026 Bq kg−1 for 238Pu and 239,240Pu, respectively. The levels of Pu activity, derived from the Sellafield nuclear fuel reprocessing effluents, in sediments are controlled by lithological factors and the influence of transport and post-depositional processes. Grain size distribution is particularly important, the major part of plutonium activity being in the mud fraction of all sediments.The data suggest that over the Irish Sea coastline, dynamic mixing of sediment grains by reworking and resuspension and/or by dispersion in tidal currents are important in determining plutonium distributions. The exponential decrease in sediment plutonium activities away from the Sellafield source is attributed to the progressive mixing with older contaminated and uncontaminated sediments.  相似文献   

12.
The standard toxicity test organism, Corophium volutator, exhibits a behavioural response to contaminated sediments that causes increased turbidity of overlying water. We quantify the effects of this response to an estuarine sediment spiked with copper and hydrocarbon contaminated sediments from an oil installation in the North Sea. Turbidity measured 24 h after the start of a toxicity test shows a strong relationship with contaminant concentrations and with mortality after 10 days. Turbidity measurements can therefore give a rapid indication of sediment toxicity, permitting a reduction in storage time of sediments to be used in dilution series and toxicity identification evaluation (TIE) tests, reducing the likelihood of contaminants degrading prior to testing.  相似文献   

13.
天津永定新河口海区海底表层沉积物的污染   总被引:4,自引:0,他引:4  
天津滨海分布着广泛的淤泥质海岸。这些淤泥质海岸因附近河流携带大量污染物入海而不同程度地受到了污染。以天津永定新河入海口附近浅海区海底表层沉积物为对象,研究了海底表层沉积物中硫化物、有机碳、石油类、重金属(Cu、Pb、Zn、Cd、Hg)和总铬的含量及其分布规律。利用单项标准指数法对沉积物的污染状况进行了分析。结果表明,沉积物中硫化物污染十分严重,总铬污染较严重,重金属污染轻微,没有有机碳和石油类污染。它们对沉积物污染程度的顺序为硫化物>总铬>Cu>Pb>有机碳>Hg>Cd>Pb>石油类。调查区污染物来源主要是通过永定新河输入的。  相似文献   

14.
Discharges of contaminated drill cuttings have caused appreciable ecological change of the benthos adjacent to many oil and gas platforms in the North Sea. Many platforms have large piles of cuttings lying beneath them and these probably present the greatest potential hazard to the environment during platform decommissioning and removal. There is, however, a lack of consensus on which aspects of drill cuttings are responsible for the adverse ecological effects. This hinders risk assessment of management options. Here we report data on the toxicity of sediments from around the North West Hutton platform to the amphipod Corophium volutator, the polychaete Arenicola marina and the Microtox" acute test system. Sediment was acutely toxic to Corophium out as far as 600 m from the platform. Sediment from 100 m from the platform remained acutely toxic to Corophium when 3% contaminated sediment was mixed with clean sediment. A 10% dilution of this sediment also inhibited Arenicola feeding almost completely. Sediment elutriates did not inhibit Microtox light output, but organics extracted by dichloromethane were very toxic. Fifteen minute EC50 values were as low as 0.25 mg ml(-1) and were strongly correlated with hydrocarbon concentrations. Metal concentrations in whole sediments were correlated with their toxicity to Corophium but the relationship was much weaker when data on dilutions were included. Except at sites immediately adjacent to the platform, metal concentrations were well below ERL values from the literature, so were too low to explain sediment toxicity. Toxicity of sediments to Corophium was closely correlated with their hydrocarbon content, even when tests on dilutions were included in the analysis. We conclude that hydrocarbons are the most significant cause of toxicity in these sediments contaminated with oil based drill cuttings and that polar organics, sulphide. ammonia and other water soluble substances are of much lower significance. Applying OSPAR guidelines to our data on the toxicity of cuttings pile material to Corophium data would give a maximum allowable concentration of 0.03% in clean sediments. The Microtox data indicate that sediments from deeper in the pile would require an even greater dilution than this.  相似文献   

15.
This study assesses the relative importance of water and sediments as vectors of TBT uptake in the sediment-dwelling suspension feeder, Ruditapes decussatus. Accumulation of TBT was determined in R. decussatus exposed for 60 days to moderately high but environmentally realistic levels of TBT in water (100 ng Snl(-1)) and sediments (0.8 microg Sn g(-1) dw), separately or in combination, using constant-flow systems. The results indicate that this species accumulates TBT predominantly from water. Although some accumulation from sediments does occur, the processing of large amounts of water needed to sustain the filter-feeding habits of this species is a prime determinant of TBT uptake. The route of exposures reflected in tissue distributions of TBT in R. decussatus. However, gills are the most important site for accumulation of TBT from water, irrespective of whether contaminated sediments are present or not.  相似文献   

16.
大亚湾表层沉积物中污染物质的地球化学行为研究   总被引:2,自引:0,他引:2  
大亚湾表层沉积物以粉砂质粘土、粘土质粉砂及粉砂为主组成。表层沉积物的污染表现以硫化物及铅、锌、汞、砷为主,其中硫化物、铅、锌的污染现象在本海区普遍出现。污染物质从海水向沉积物转移是多因素综合作用的结果,悬浮物、生物及沉积物的吸附等多种转移方式都可能存在。沉积物中某些元素之间存在一定的相关性,但沉积物与其粒度组成的粘土含量及海水理化要素之间无明显相关性。  相似文献   

17.
基于沉积物重金属污染风险评估系统的不确定性和随机性,采用Monte Carlo模拟技术定量刻画沉积物重金属含量数据分布特征,并通过与潜在生态风险指数法的综合集成,评估了独山港海域表层沉积物重金属(Cu、Pb、Zn、Cr、Cd、Hg和As)的潜在生态风险水平。结果表明,港区中Cu、Pb和Zn为中等污染,Cd、Cr、Hg和As为轻微污染;综合污染指数Cd处于轻微污染的概率为38.32%,处于中等污染的概率为61.68%。所有7种重金属污染程度以及潜在生态风险指数RI均为轻微级。敏感性分析表明,Cu、Zn和Cr对CdRI起主导作用。  相似文献   

18.
A simple laboratory microcosm system, previously used as a community level sediment bioassay for laboratory contaminated sediments, has been used for testing contaminated field sediments. Meiobenthic communities from the Lynher Estuary were incubated with defaunated sediment collected from the Fal Estuary system where a gradient of heavy metal concentrations is reflected in meiofaunal community structure. In the microcosms changes in nematode community structure were related to sediment metal concentrations. These changes in community structure were similar to those previously observed between creeks in the Fal Estuary system indicating that an experimental microcosm approach can be useful both as a sediment bioassay and in the validation of conclusions drawn from field surveys.  相似文献   

19.
Role of mangrove in mercury cycling and removal in the Jiulong Estuary   总被引:4,自引:0,他引:4  
Baseline of mercury in mangrove swamp The mercury content in sediments in the Jiulong Estuary was determined in 1984 and 1985(Table 1). The highest content of mercury in sediments (300×10~(-9)) was found in Ditou, contrast-ing strongly with the low content of 36×10~(-9) in Port Dongzhai in the Hainan Island. Tab1e 1 showsthat the average content of mercury in sediments in the Jiulong Estuary is 140×10~(-9) and the averageof four areas is 72×10~(-9). This value means that these areas have not been heavily contaminated by  相似文献   

20.
The Elizabeth River is Virginia's most heavily populated, industrialized and contaminated subestuary. Its sediments contain the residues of wastes discharged for several hundred years. To examine some of the effects of sediment from a particularly noxious location, we chose the spot (Leiostomus xanthurus), a bottom-feeding sciaenid and naturally occurring spring-summer migrant of the river whose juveniles adapt readily to laboratory conditions. Spot from the Ware River, a nearby uncontaminated reference subestuary, were placed in two 380 liter (100 USgal), flow-through tanks (70 each). One tank contained Elizabeth River sediments contaminated with PAHs. The second tank contained uncontaminated sediment from the York River as a control. 13 spot each were placed in two aquaria that received the overflow from the sediment-containing tanks. Animals from the reference estuary were examined and processed to provide baseline information.Results obtained to date show the following: (1) spot experimentally exposed to contaminated sediment developed penetrating integumental lesions within 8 days after exposure began and later severe fin and gill erosion; (2) their hematocrits were significantly reduced and no weight gain occurred; (3) pancreatic and liver alterations were observed in some of the chemically stressed fish; (4) control fish exhibited no fin erosion or integumental lesions; (5) control fish showed no hematocrit or growth reduction; and (6) dead fish were first observed in the contaminated-sediment tank after 8 days while no control fish died. Clearly, one or more factors associated with Elizabeth River sediments and/or water closely associated with those sediments (probably the heavy concentrations of PAHs) are capable of causing serious injury, disease and death in experimental spot populations.  相似文献   

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