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1.
Effects of acute cadmium poisoning on survival, its residual values and histopathology in certain organs of a freshwater airbreathing fish, Channa punctatus (BLOCH ) were investigated. The threshold concentration, MATC and LC50 values obtained from 96 h static bioassay, revealed that Channa is more susceptible to cadmium ions at higher temperature. The atomic absorption spectrophotometric determination of cadmium residues differed significantly in organs of specimens having survived and died after 96 h of exposure. The gill accumulate the highest amount of cadmium, the liver accumulated a slightly smaller amount than the gill, while the kidney accumulated the least. The histopathological lesions subjected to sublethal (5.2 mg/l Cd) and lethal (8.4 mg/l Cd) concentrations of cadmium were: detachment and rupture of lamellar epithelium, collapse of pillar cells and hypertrophy in mucus producing gland cells in the gill; vacuolization and coagulative necrosis in hepatic cells of the liver; and expansion, necrosis and accumulation of cellular debris in renal tubules of the kidney. The probable causes for death of fish due to cadmium ions have been discussed.  相似文献   

2.
The toxic effects of alkali cyanide, complex cyanide-containing heavy metal salts—as of iron, cadmium, copper, nickel and mercury—were investigated according to standard methods with the aid of the test organisms Poecilia reticulata (guppy) as well as the green alga Ankistrodesmus falcatus (β- bis α-mesosaprobic). Since various complex compounds can be photolytically decomposed, also discontinuous light-dark phases were used. As discussed equilibrium calculations have shown, inter alia also the pH-value is important in the fish organisms used with different reactions to ions and molecularly dissolved compounds. The results are summarized in tables and graphic representations, the substances investigated being classified into groups with “strong” and “high” toxic actions.  相似文献   

3.
The present paper deals with the evaluation of the relative resistance of 12 species of fish in static toxicity bioassay tests of electroplating waste. The electroplating waste is highly toxic as it contains several toxic metals like copper, nickel, cadmium, zinc, lead and chromium alongwith cyanides, acids and alkalies. On the basis of TL50, the fish Clarias batrachus ist the most resistant fish and Labeo rohita the most sensitive. The relative resistance of the fish is in the decreasing order: Clarias batrachus, Saccobranchus fossilis, Ophiocephalus gachua, Ophiocephalus punctatus, Puntius stigma, Puntius sophore, Mystus vittatus, Cyprinus carpio, Colisa fasciatus, Notopterus notopterus, Cirrhina mrigala and Labeo rohita.  相似文献   

4.
This paper deals with the toxicity of sodium nitrite to freshwater fishes, Channa punctatus (BL.) and Mystus (M). vittatus (Bl.) as to determine the acute toxicity. The LC 50 values were obtained by using a static bioassay method for a period of 24, 48, 72 and 96 hour intervals. The LC 50 values of sodium nitrite for C. punctatus were 375, 325, 250 and 200 ppm and for M. (M). vittatus 164, 140, 90 and 64 ppm, respectively. A profuse mucus secretion was evident at higher concentrations as compared to lower ones. The probable causes of mortality of the fishes are also discussed.  相似文献   

5.
Fate and effect of copper and cadmium on the degradation of chitin were studied in sediment microcosms. Artificial sediment was spiked with metals, and metal partitioning between sediment components, overlying water and bacteria was described. Most of the added metals were bound to sediment particles. Remarkable metal enrichments were found on Fe-oxide, Mn-oxide, and chitin. In sediments containing the nominal concentration of 100 mg/kg Cu, the chitin-degrading bacteria Cytophaga johnsonae showed a significant decrease in N-acetylglucoseaminidase activity. Toxicity of copper was attributed to free ions in the overlying water. The bacteria were more sensitive to copper than to cadmium. Inhibitory effects of cadmium were primarily caused by sediment-associated cadmium.  相似文献   

6.
Three experiments were conducted with Atlantic salmon (Salmo salar) to assess the effects of dietary exposure to copper and cadmium. The results presented here provide an overview, details of each experiment will be published in full elsewhere. In the first experiment, salmon parr exposed for four weeks to 35 and 700 mg Cu kg−1 diet had significantly elevated intestinal copper concentrations, cell proliferation (PCNA) and apoptosis rates compared to control fish. No differences were observed in gill or plasma copper concentrations among the groups. In contrast to the controls, the Cu exposed groups did not grow significantly during the exposure period. The second experiment (three months exposure) was conducted to assess the effects of dietary copper (control, 35, 500, 700, 900 or 1750 mg Cu kg−1 diet) on growth and feed utilization in salmon fingerlings. Growth was significantly reduced after three months exposure to dietary Cu concentrations above 500 mg kg−1. Similarly, copper body burdens were significantly higher in fish exposed to elevated dietary copper concentrations (above 35 mg Cu kg−1 diet). In the third experiment, salmon parr were exposed to one of six dietary cadmium concentrations (0, 0.5, 5, 25, 125 or 250 mg Cd kg−1 diet) for four months. Cadmium accumulated in the liver>intestine>gills of exposed fish. Rates of apoptosis and cell proliferation in the intestine increased following exposure to dietary cadmium. Exposure to elevated concentrations of dietary cadmium had no effect on growth in salmon parr. Results from these studies indicate that cellular biomarkers have potential as early warning signs of negative effects on the overall fitness of an organism.  相似文献   

7.
Acute toxicty tests (LT50) of copper or cadmium on the crustacean isopod Idothea baltica demonstrated differences between females, males, and juveniles. Copper appears to be more toxic than cadmium. the effects of chronic exposure to 5 μl−1 and 500 μl−1 copper or cadmium were evaluated from survival, body growth, and sex ratio in the first stages of juveniles development. While in juveniles 500 μl−1 significantly affected body growth, sex ratio, and survival, 5 μl−1 affected only survival. The study of the long-term effects of a pollutant on different demographic parameters in a species can serve to assess a ‘safe’ level of environmental contamination.  相似文献   

8.
  • - In the present paper the toxicity of four biocides, endrin, thiodon, malathion and phosvel, has been measured by performing static bioassay experiments with Channa gachua as test fish to establish the median Tolerance Limits (TLm and TL50).
  • - The results of bioassay experiments indicate that the fish is harmed even at a very low concentration of these biocides. The values of TLm are 0.0076, 0.0073, 0.00695 and 0.0068 for endrin; 0.01120, 0.01088, 0.01069 and 0.01064 for thiodon; 9.20, 8.10, 7.90 and 7.60 for malathion and 32.90, 32.10, 31.65 and 31.15 mg/l for phosvel for the time interval of 24, 48, 76 and 96 hours, respectively.
  • - As indicated by TLm's, endrin is most toxic and phosvel least. Thiodon and malathion came in a descending order between endrin and phosvel.
  • - During bioassay studies, the effect of some variables, like temerature, pH and fish-size, on TLm's has also been observed. They gave the following results.
  • a) An increase in temperature increased the toxicity of all the biocides.
  • b) An increase in pH decreased the TLm as such, making the biocides more toxic to Channa gachua.
  • c) For larger fishes, the biocide solutions were less toxic, but the same solutions were more toxic to fishes of a smaller size.
  • - The safe harmless concentrations of endrin, thiodon, malathion and phosvel are - 0.00289 mg/l, 0.00337 mg/l, 1.88365 mg/l and 9.16736 mg/l, respectively.
  相似文献   

9.
The present study was undertaken to evaluate the comparative toxicity of Thiotox (Endosulfan) (an organochlorine), Dichlorvos (DDVP) (an organophosphorus) and Carbofuran (a carbamate) so as to determine the TL 50 values, acute toxicity ranges, relative toxicities, relative susceptibility, safe concentrations, regression equations, heterogeneity factor and 95% confidence limits for the period of 24, 48, 72 and 96 h, taking two fresh water teleosts, Mystus vittatus and Ophiocephalus punctatus as test animals. From the relative toxicity of these pesticides it is evident that thiotox was the most toxic and dichlorvos the least toxic one, while the toxicity of carbofuran was in between these two extremes for both the fishes. On the basis of relative susceptibility, Mystus vittatus was found to be more susceptible than Ophiocephalus punctatus for thiotox, dichlorvos and carbofuran, respectively. The safe concentrations were computed for all the three pesticides taking different application factors, so as to avoid the long term water pollution by these pesticides.  相似文献   

10.
New biocide-free anti-fouling paints are toxic   总被引:1,自引:0,他引:1  
A number of new anti-fouling paints claimed to be more friendly to the environment, have entered the market since prohibition of biocide containing paints have been enforced in many areas. Leakage waters from five new anti-fouling paints were tested for toxic effects to the macro algae Ceramium tenuicorne and Ceramium strictum and to the crustacean Nitocra spinipes. A banned copper and irgarol 1051 containing anti-fouling paint was used as reference. Five of the six paints tested were toxic to all or some of the organisms after two weeks of leakage with EC50 ranging from 0.08 to around 2% leakage water and LC50 ranging from 1.1% to 88%. The toxicity of leakage water from these paints was still high after 16 weeks. We conclude that these paints contain substances toxic to common organisms in the coastal Baltic ecosystem. A silicone based paint did not exhibit toxic effects to the two organisms. We recommend that biological tests should be used to identify the most harmful products before they are released on the market.  相似文献   

11.
Effects of cadmium on the fertilizing capability of spermatozoa, dynamics of the first cleavage and pluteus formation in the sea urchin, Anthocidaris crassispina, were investigated. Exposure to cadmium concentrations of 0.32, 0.56, 1.0, 1.8, 3.2, 5.6 and 10.0 mg l−1 for 30 min caused a significant adverse effect on the fertilizing capability of spermatozoa (EC50=1.7 mg l−1). For the first cleavage kinetics assay, eggs were pre-exposed to 0, 0.18, 0.32, 0.56, 1.0, 1.8, 3.2 and 5.6 mg l−1 of cadmium for 30 min. Fresh sperms of fixed concentrations were then added to the eggs and the percentage of divided zygotes estimated. Concentration-dependent toxic effects on the dynamics of the first cleavage in A. crassispina were observed between 0.18 and 5.6 mg l−1 cadmium. Calculation of EC50 values by probit analysis at different stages of the first cleavage revealed that EC50 values increased gradually from 0.37 mg l−1 at the beginning to 2.24 mg l−1 at the end of the cleavage process. Different larval classes (normal, abnormal and retarded plutei, preplutei, dead embryos/larvae) of A. crassispina obtained from eggs pre-treated with cadmium for 30 min and then exposed to cadmium throughout embryogenesis were also examined. The percentage of abnormal plutei was significantly higher than that of the control at 0.56 mg l−1 cadmium and higher. The 48 h EC50 calculated for the number of normal plutei was 1.5 mg l−1. A χ2-test revealed significant changes in the distribution of proportions of different larval classes only at cadmium concentrations 1.8 mg l−1. At 5.6 mg l−1 of cadmium, small malformed plutei, and oval embryos with rudimentary skeleton, poorly differentiated intestines and no mouth (pre-pluteus stage) were observed. The relative sensitivity of various end points to cadmium is also compared and discussed.  相似文献   

12.
Concentrations of arsenic, cadmium, chromium, copper, lead, mercury, selenium, and zinc were measured in coral, crab, eel, fish, lobster, and sediment samples collected from French Frigate Shoals, North Pacific Ocean. The sediments contained relatively high concentrations of selenium; moderate concentrations of arsenic, cadmium, copper and lead; and low concentrations of chromium and zinc. Metal concentrations were also determined in coral and crabs collected from the island of Oahu. Notably, a crab (Grapsus tenuicrustatus) and the undulated moray eel (Gymnothorax undulatus) exhibited high levels of copper and arsenic, respectively, relative to the other species studied. The concentrations of arsenic in the eel averaged 225 microg g(-1) dry wt, which was 3-12 times higher than that in all of the other species tested. The average concentration of copper in the crab was 343 microg g(-1) dry wt, 3-86 times greater than that in the other species studied. These data indicate background and comparative levels of the metals among the studied species. Lead levels in the coral (9-10 microg g(-1) dry wt) and crab (42-57 microg g(-1) dry wt) from Tern and Disappearing Islands were 23-283-fold greater than those from Oahu (0.4 and 0.2 microg g(-1) dry wt, respectively).  相似文献   

13.
The exposure of catfish, Heteropneustes fossilis to different concentrations (200, 500, 700, 1000, 1500, 2000 ppm) of crude oil extract for a varying period (for up to 48 h in lethal extract and 360 h in sublethal one) resulted into a number of haematological changes. All the parameters taken here were found to have been increased except the haemoglobin level which fell down to 14.3 % in an acute lethal concentration (2000 ppm) after 48 h of exposure. The haematocrit value increased significantly (12 %) in 2000 ppm. The blood sugar level showed hyperglycemia in all the concentrations. The increase in ascorbic acid (28 %) was pronounced in higher concentrations. Changes occurring in different parameters seemed to be reversible as all the parameters returned to their normal levels after returning the fish to normal media, except the nuclear swelling which did not resume the normal functioning even after a prolonged treatment (1 month or more) in the recovery jar. The haematological effects shown by the crude oil resembled partly those kept in severe hypoxic conditions and partly to the fishes poisoned by heavy metals (Cu and Zn). On the basis of results obtained in this investigation, crude oil may be categorised as a complex toxic agent.  相似文献   

14.
The fish Cyprinus carpio (HAM.) and Channa punctatus (BL.) of the size ranging between 6.0 ± 1.2 cm and 28.0 ± 1.6 cm were exposed to different concentrations of industrial effluents from M/s Punjab Tannery Ltd. (Jalandhar), M/s Spinning Mill Ltd. (Hoshiarpur) and M/s Food Specialist Ltd. (Moga) for evaluating the influence of fish size on the acute toxicity of these effluents. Results indicate that the relative toxicity of the effluents decreased with the increase in fish size from 6.0 ± 1.2 cm to 20.6 ± 1.5 cm. However, for specimens of the size of 28.0 ± 1.6 cm and more, the toxicity of the effluents increased with an increase in fish size. On the basis of the relative toxicity to fish, effluent from Punjab Tannery was found highly toxic and from Food Specialist Industry, the least toxic.  相似文献   

15.
《Marine pollution bulletin》2014,78(1-2):130-136
For heavy metals, quality standards indicating good environmental status are designed to evaluate concentrations in the whole fish body, whereas monitoring of metals is often conducted using muscle or liver tissue. As most metals accumulate at different rates in different parts of fish, data should be adjusted to reflect whole fish body concentrations; however, this requires knowledge on distribution of metal concentrations within fish. Here, concentrations of cadmium, mercury, and lead were analyzed in the liver, muscle and whole fish of herring and perch to create conversion factors for transformation of heavy metal concentrations between these tissues. Species-specific accumulation of metals between muscle, liver, and whole fish were observed. Relationships between different tissues were used to recalculate data from monitoring programs in the Baltic Sea region. Based on whole fish concentrations, environmental status for cadmium and mercury in herring improved compared to assessments based on muscle or liver concentrations alone.  相似文献   

16.
太湖渔业资源现状(2009-2010年)及与水体富营养化关系浅析   总被引:6,自引:3,他引:3  
根据2009-2010年的太湖鱼类资源调查,结合历年渔业资料和水环境监测数据,分析太湖渔业资源的发展趋势和结构特征.结果表明:本次调查共采集到鱼类47种,隶属10目14科37属,原常见鱼类种类数明显减少,鲤科等定居性鱼类成为主体;同时,太湖渔业产量近年来增长迅速,渔获物中湖鲚等小型鱼类比重增加,渔业资源的单一化和小型化趋势加剧.根据湖泊水体环境特征的空间差异,对太湖东部湖区、北部湖区和湖心区3个不同类型湖区间的渔业资源特征进行比较.其中在北部湖区和湖心区,浮游食性的湖鲚成为绝对优势种,2008年其产量分别占湖区总产量的70.7%和80.4%,其他主要鱼类所占比重仅为0.2% -3.0%;而东部湖区草食性和肉食性鱼类的比例较高,鱼类结构相对合理,不同湖区间渔获物的组成差别反映出湖区鱼类组成与环境特征相适应的特点.针对太湖渔业资源与水体富营养化关系进行探讨,提出需加强渔业与湖泊环境功能之间关系的研究,重视水生植被在太湖渔业可持续发展中作用的建议.  相似文献   

17.
水体生态环境中的微塑料与重金属污染问题正日益受到热切关注为探讨微塑料与重金属对水产品的复合生态效应,选择鄱阳湖饶河段优势淡水鱼为研究对象,对鱼体内微塑料及重金属Cu、Cd、Pb、Zn、Cr等元素的生物累积作用进行分析与评价结果表明:调查区域水环境中微塑料的丰度范围10~64 items/L,平均值38.56 items/L. 8种淡水鱼消化道微塑料丰度范围为1.21~9.11 items/g,平均丰度为5.40 items/g;鳃部丰度范围0.61~5.00 items/g,平均丰度为2.87 items/g;微塑料类型主要有碎片类、纤维类、薄膜类和颗粒类4种,其聚合物成分主要为聚乙烯(PE)、低密度聚乙烯(LDPE)、聚丙烯(PP)和聚苯乙烯(PS);颜色以透明及彩色为主;微塑料粒径范围为0.01~9.5 mm,粒径0.5 mm的微塑料所占比例为79.07%,鱼体内与其生存水环境中微塑料的丰度特征(形态、粒径、颜色和聚合物类型组分比例)具有一定相似性各鱼类对微塑料的累积系数(BAF)平均值为178.29,不同鱼类累积微塑料的能力大小次序为:乌鳢(Channa argus)、黄颡鱼(Pelteobagrus fulvidraco)鲦鱼(Hemicculter leuciclus)、草鱼(Ctenopharyngodon idellus)、鲶鱼(Silurus asotus)鲤鱼(Cyprinus carpio)、刀鱼(Coilia ectenes)、鲫鱼(Carassius auratus)鱼体肌肉组织内重金属Cu、Cd、Pb、Zn、Cr的平均含量分别为4.27、0.13、0.28、11.73、0.53 mg/kg,均符合无公害水产品的要求且低于人体消费卫生标准,属于安全食用范围;鱼类对5种不同重金属的累积能力大小次序为ZnCuCdPbCr,不同鱼类对不同重金属的累积能力具有差异性通过扫描电镜(SEM)与能谱分析(EDS)检测到各类型微塑料表面均有上述5种重金属元素,证实微塑料可能成为重金属的附着载体,相关性分析表明微塑料与Cu呈极显著相关,与Cd、Pb均呈显著相关;微塑料的存在一定程度上会增强Cu、Cd与Pb的累积效应,并可能产生复合污染效应.  相似文献   

18.
Trace metals in fish and invertebrates of three California coastal Wetlands   总被引:1,自引:0,他引:1  
Metal concentrations were measured in selected fish and invertebrate species from Mugu Lagoon, Malibu Lagoon and Ballona Wetlands in southern California in order to assess the extent of metal contamination in these three wetlands. Ranges of element concentrations (in microgram/g) found in biota were: Zn 12-650; Cu 1.9-440; Ni < 1-37; Cr < 1-55; Pb < 0.5-6.8; As < 1-8.5; Se < 1-3.8; Cd < 0.2-0.90; and Ag < 0.3-5.9. Relative to previous studies of California biota, the highest metal concentrations found were for chromium and nickel. The highest levels were in one of the two bottom-dwelling fish (juvenile Leptocottus armatus) (55 micrograms/g) and the two water-column fish sampled (Fundulus parvipinnis and Atherinops affinis) (30 and 24 micrograms/g). At Ballona Lagoon, elevated levels of copper and silver were found in the bivalve Tagelus californianus (440 and 5.9 micrograms/g). Chromium and nickel appeared to be most persistent in fish from Mugu (4.6-55 and 2.6-37 micrograms/g), the most northern site and an active military base, and Ballona (< 1-30 and < 1-16 micrograms/g), believed to be the most metal-contaminated site. Compared to previously measured metal concentrations in species of California coastal waters, these regions revealed higher levels of chromium, nickel, silver, arsenic, zinc, copper and, to a lesser extent, cadmium and selenium. Chromium and silver were present at high enough levels at all three sites to be considered environmental health hazards.  相似文献   

19.
Acute toxicity of heavy metals to some marine larvae   总被引:1,自引:0,他引:1  
The toxicity of copper, mercury and zinc to the larvae of oysters, shrimp, crab and lobsters has been examined over periods of up to 64 hours. Mercury was found to be more toxic than copper and zinc, which had similar levels of toxicity. Over the experimental period, the relationship between toxicity and concentration was linear. Larvae were from 14 to 1,000 times more susceptible than adults of the same species. The median lethal concentrations (LC50) of each metal to the most sensitive species of larvae, tested over a 48 hour period, exceeded the concentrations found in natural sea water by a factor of 100. For longer test periods, the LC50 would be considerably less and this factor would then be considerably reduced. Hence the continued addition of these metals to confined waters should give cause for concern.  相似文献   

20.
At present, there is a very limited information on the levels and distribution of dissolved metals in Manila Bay. In this study, the horizontal and vertical distribution of operationally defined species (labile, bound and total) of dissolved copper (Cu), cadmium (Cd) and zinc (Zn) were determined using differential pulse anodic and cathodic stripping voltammetry in water samples obtained from 18 stations in November 1998. In addition, the 24-h variability in the concentrations of these species at different depths in the water column was determined. These measurements were complemented by the determination of temperature, salinity, dissolved oxygen, chlorophyll a, particulate organic carbon and nutrients. Results showed that more than 50% of total dissolved copper and cadmium were labile while 50% of total dissolved zinc was organically bound. Vertical profiles showed that Cu, Cd and Zn concentrations were generally high at the surface. Zinc and cadmium were characterised by the presence of a mid-depth minimum while copper did not show any clear vertical trend.

Dissolved Cu concentrations during the spatial and diurnal samplings ranged from 0.32 to 6.95 nM and 1.52 to 45.65 nM, respectively. For Cd, the concentrations in 18 stations ranged from 0.05 to 2.92 nM, and from 0.03 to 2.42 nM over a 24-h period. Zn concentrations ranged from 2.48 to 147.43 nM and 2.87 to 88.27 nM during the spatial and diurnal samplings, respectively. The large variation in the concentration of Cu, Cd and Zn in the bay was observed to be associated with the presence of a large vertical density gradient in the water column, which appeared to limit the exchange of materials between the surface and bottom waters. Elevated levels of these metals near point sources suggest anthropogenic inputs in the bay.  相似文献   


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