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1.
The marine bivalve, Perna viridis was exposed to sublethal concentration (one third of 24 h LC50) of either cadmium or copper for 1, 3 and 7 days and alterations in lipid peroxidation in the gill and muscle were investigated. Significant increase of the level of malondialdehyde, which is indicative of the peroxidative process, and a decrease of activity levels of glutathione peroxidase and glutathione transferase were observed in both the tissues of copper exposed mussels. the exposure of mussels to cadmium did not elicit any of the above changes.  相似文献   

2.
The chemical composition of inorganic granules found in parenchyma cells surrounding the midgut of adult Balanus balanoides (L.) was determined. X-ray microanalysis indicated the presence of magnesium, phosphorus, potassium, calcium, iron and zinc in the granules. A quantitative analysis of granule-rich pellets isolated from the midguts of adult barnacles showed that the granules were composed mainly of zinc phosphate, the remaining elements being minor constituents only.  相似文献   

3.
In the present study, an attempt has been made to quantify the fenvalerate accumulated in different tissues (gill, muscle and liver) and observe changes involved in the levels of sodium, potassium and calcium ions and Na+–K+, Mg2+ and Ca2+ adenosine triphosphatase (ATPase) activities in the freshwater fish, Cirrhinus mrigala on short-term and long-term exposure to the median lethal and sublethal concentration of fenvalerate. Residue analysis using gas–liquid chromatography (GLC) technique revealed that fenvalerate accumulated in highest quantity in gill followed by liver and muscle under median lethal concentration (6?µg?L?1). Whereas in sublethal concentration (0.6?µg?L?1), muscle accumulated highest quantity followed by gill and liver, which might be due to the fact that fenvalerate is highly lyphophilic. The ion concentration and ATPase activity were found effected in fish exposed to lethal and sublethal concentrations of fenvalerate. Concentration of Na+, K+ and Ca2+ ions decreased in gill, muscle and liver on being exposed to median lethal concentration to a significant level. Whereas the changes were not highly pronounced at sub lethal level indicating low concentration of fenvalerate and its non-toxic effect at chronic exposure. Na+–K+, Mg2+ and Ca2+ ATPases activity were also found decreased in correspondence to the ionic change under median lethal and sub lethal concentrations in target tissues. This might have lead to behavioural changes and create wide-spread disturbance in the normal physiology, ultimately causing the death of the fish. The results suggest that in biomonitoring programmes, ions and associated ATPases can be a good diagnostic tool for fenvalerate toxicity.  相似文献   

4.
镉对籽粒苋耐性生理及营养元素吸收积累的影响   总被引:3,自引:0,他引:3  
李虹颖  苏彦华 《生态环境》2012,21(2):308-313
初步阐明了镉对籽粒苋耐性生理及营养元素吸收积累的影响,为进一步揭示籽粒苋的镉耐性与镉富集机理奠定了基础。通过对生物量的监测,对叶绿素、蛋白质、游离氨基酸、大量元素及微量元素等的含量的测定,阐明镉胁迫对籽粒苋生长生理、抗胁迫耐性、营养元素吸收分配的影响。研究结果显示,镉胁迫对籽粒苋的生长抑制作用不明显,植株生物量随着镉浓度的提高而轻微降低。随着镉处理浓度的提高,叶绿素含量下降幅度显著;蛋白质和游离氨基酸含量变化幅度不明显;钾含量无大幅变化;镉、磷、钙、镁、锌、铁、锰、铜含量变化幅度较显著。镉、钾、磷、锰的迁移系数随着镉处理浓度的提高无显著变化;钙的迁移系数呈上升趋势;镁、锌、铁、铜的迁移系数均呈下降趋势。这些结果表明:镉胁迫降低籽粒苋叶绿素含量,抑制植株光合作用,继而抑制了植株的生长,但其程度不明显;镉胁迫条件启动活性氧防御机制;引起植株体内部分养分代谢紊乱。结论:低浓度镉处理条件下,籽粒苋受镉离子影响,抗氧化能力下降。在高浓度镉处理条件下,籽粒苋调节了营养元素的吸收和分配,启动了一系列活性氧防御机制,提高了抗胁迫能力。  相似文献   

5.
The sublethal toxicity of sodium arsenite on protein metabolism was investigated in teleost fish, Tilalpia mossambica at the end of 24, 48, 72 and 96 h of exposure. Total protein content, free amino acid content and activities of the enzymes aspartate amino transferase (AAT) and alanine amino transferase (ALAT) in liver, gill, brain and muscle exhibited significant (P<0.05) alterations throughout the investigation in relation to that of control. It is suggested that the fish is able to respond to the stressful situations by gearing up the metabolic activity as revealed by the elevated protein, amino acid content and the activities of AAT and ALAT.  相似文献   

6.
The aim of this study was to develop new antidotes for cadmium (Cd) since this metal is known to produce mammalian toxicity. N-p-hydroxymethylbenzyl-D-glucamine dithiocarbamate (HBGD), N-benzyl-D-glucamine dithiocarbamate (BGD), diethyldithiocarbamate (DDTC), 2,3-dimercaptopropanol (BAL), and ethylenediamine-tetraacetic acid (EDTA) were studied for their ability to inhibit the adverse effects induced by Cd on mouse testes. The parameters examined included concentrations of Cd, calcium (Ca), iron (Fe), and zinc (Zn) in testes, lipid peroxidation (LPO) levels in testes, lactate dehydrogenase (LDH) activity in serum and reproductive ability of male mice. Mice injected intraperitoneally (ip) with CdCl2 (2.5?mgCd?kg?1) after 30?min or 24?h, were then injected ip with chelating agents (400?µmol?kg?1). Cd increased the concentrations of testicular Ca, Cd, Fe, Zn, and LPO levels as well as the activity of LDH in serum. HBGD and BGD effectively prevented the increase in above indices, and improved the reproductive ability weakened by exposure to Cd. The results suggested that HBGD and BGD are more effective detoxificants in the case of testicular toxicity in mice induced by acute exposure to Cd.  相似文献   

7.
Weekly measurements of chemical composition were made at four sampling sites on the Lea River (Spain) between July 1985 and August 1986. at two stations there were gauging-weirs for stream discharge monitoring. Conductivity, pH, alkalinity, silicon, calcium, magnesium, sodium, potassium, ammonia, nitrate, sulphate, chloride, reactive phosphate, and total phosphate, were recorded in each site.

Results were analysed using multiple regression techniques to study the relationship between flow and chemical components.

Conductivity, alkalinity, calcium, magnesium and sulphate were strongly related to flow, decreasing in concentration with increased flow. Ammonia, potassium, reactive phosphate and total phosphate varied most widely, with peaks at times of heavy rainfall. Nitrate increased at times of high discharge, with little variation between sampling points. Silicon decreased in summer and autumn in the lower catchment area whilst chloride and sodium were higher in the lower catchment of the River Lea.  相似文献   

8.
环境中的镉污染对动植物及人类都带来了极大的危害。目前,多数镉毒理研究关注其无机状态,而来源于稻米的有机态镉的毒害作用报道较少。为评估稻米来源镉对生长期猪的毒性作用,选用初始体重为30 kg左右的健康生长猪28头,随机分为体重无明显差异的2组,即对照组与稻米来源镉组(试验组),研究稻米来源镉对生长期猪(生长及育肥全阶段)的生长特性及不同脏器组织镉蓄积的影响。结果表明,在生长及育肥阶段,试验组与对照组相比:1)生长特性无显著差异(P0.05);2)育肥期组织游离氨基酸含量,除肌肉中的赖氨酸显著降低外(P0.05),血浆、肝脏、肾脏及肌肉中其他游离氨基酸水平均无显著差异(P0.05);3)心脏、肝脏、脾脏、肾脏、肺脏、胃、小肠、大肠、骨骼中镉蓄积量显著增高(P0.05),而肌肉、血液中无显著差异(P0.05),脂肪、皮中未检出镉。日粮使用大比例镉超标稻米后镉在各脏器和组织中的蓄积规律为肾脏肝脏小肠脾肺大肠胃血液骨头心腿肌背肌脂肪、皮。由此可见,镉超标稻米对生长期猪的生长特性未产生显著的影响,稻米来源镉主要蓄积于肝脏和肾脏,而主流食用组织肌肉和血液中镉的蓄积量较少。  相似文献   

9.
Alterations in the levels of lipid metabolites, total lipids and free fatty acids, were studied in physiologically important tissues viz; liver, muscle, kidney and ovary of a freshwater edible fish Clarias batrachus. The fish was exposed to sublethal concentration (1/3 of LC50 value for 96?h) of a synthetic pyrethroid insecticide, cypermethrin for 1, 5 and 10 days. After 10 days of exposure, fish were released into fresh water and total lipids and free fatty acids were determined at intervals of 1, 5 and 10 days to assess fish recovery response after cessation of cypermethrin exposure. Fish showed an increased rate of lipogenesis in liver, muscle, kidney and ovary during the exposure period followed by a decrease after transfer of fish into fresh water. There was also an elevation in liver and kidney free fatty acids contents, while the muscle and ovary free fatty acid contents were reduced during exposure period. The alterations in free fatty acids were restored to near normal values after 10 days of cessation of exposure.  相似文献   

10.
The study investigated the effect of calcium (Ca) supplementation on lead-induced toxicity in suckling male Wistar rats. The sucklings were exposed to lead acetate (5 mg/kg b wt./week) orally for a period of six weeks. The unexposed group of sucklings was the negative control. Out of the lead-exposed groups, two groups were supplemented with Ca at 3% and 6% as CaHPO4 × 2H2O in suspension in cow's milk. The artificial feeding regimen was followed for 7 h each day for 6 weeks. Sucklings exposed to lead with Ca supplementation recorded a significantly higher increase in body weight and a significant reduction of lead concentration in all tissues. The lead-induced histopathological alterations in the liver and kidney were also reversed with Ca supplementation. Sodium rhodizonate staining of liver sections showed distinct presence of lead granules in the group exposed to lead while the Ca-supplemented groups were comparable to the control. Lead exposure reduced the expression of rad 51 in the testis and liver which was markedly enhanced with Ca supplementation and was restored to the level in the control. Thus, Ca supplementation during the suckling period was effective in ameliorating the lead-induced toxicity.  相似文献   

11.
L-Cysteine has protective efficacy in cases of oxidative tissue injury. Sodium valproate is widely used as an anticonvulsant and an antidepressant in spite of hepatotoxicity as side effect. The aim of this study was to evaluate the protective role of L-cysteine in liver toxicity induced by sodium valproate overdose. Release of the hepatic enzymes, aspartate aminotransferase and alanine aminotransferase, and levels of lipid profiles, as well as the oxidative, enzymatic, and non-enzymatic antioxidant were assessed. Liver damage was judged histologically. L-Cysteine decreased the activity of alanine aminotransferase and aspartate aminotransferase, as well as improved the level of lipid profile, increased the enzymatic antioxidant (catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase), and decreased the lipid peroxidation. L-Cysteine administration inhibited liver injury of sodium valproate.  相似文献   

12.
The sea urchin Lytechinus variegatus is capable of surviving chronic exposure to sodium phosphate (inorganic phosphate) concentrations as high as 3.2 mg l−1, and triethyl phosphate (organic phosphate) concentrations of 1,000 mg l−1. However, chronic exposure to low (0.8 mg l−1 inorganic and 10 mg l−1 organic phosphate), medium (1.6 mg l−1 inorganic and 100 mg l−1 organic phosphate) or high (3.2 mg l−1 inorganic and 1,000 mg l−1 organic phosphate) sublethal concentrations of these phosphates inhibits feeding, fecal production, nutrient absorption and allocation, growth and righting behavior. Food consumption and fecal production declined significantly in individuals exposed to medium and high concentrations of inorganic phosphates and all levels of organic phosphates. Feeding absorption efficiencies for total organics and carbohydrates decreased significantly in individuals held in the highest concentration of organic phosphate. Feeding absorption efficiencies for lipids were significantly reduced in the highest inorganic phosphate concentration only, while they decreased significantly for protein with increasing phosphate exposure. Carbohydrate and lipid levels in gonad and gut tissues decreased significantly with exposure to increasing phosphate concentrations, potentially impairing both gametogenesis and nutrient storage in the gut. Moreover, gonad indices significantly decreased in individuals exposed to the highest concentrations of either phosphate. Growth rates decreased significantly under the influence of all phosphate concentrations, while increasing in seawater alone. Individuals exposed to increasing phosphate concentrations showed reduced righting responses (a measure of stress) and no acclimation in righting times during chronic exposure to phosphates over a 4 week period. These findings indicate that shallow-water populations of L. variegatus subjected to inorganic and organic phosphate pollutants will exhibit stress and be inhibited in their growth and performance due to reductions in feeding, nutrient absorption and allocation of nutrients to key somatic and reproductive tissues. Received: 10 April 2000 / Accepted: 2 October 2000  相似文献   

13.
The mussel Mytilus edulis is extensively used to monitor metal contamination of estuarine and marine systems. Nonetheless, the mechanisms of metal uptake are poorly understood. To characterise the systems involved in cadmium and zinc uptake, the interaction between the two metals and the effects of different calcium channel blockers (diltiazem, nifedipine, verapamil) and inhibitors of active transport and metabolism (ouabain, sodium cyanide, 2,4 dinitrophenol) on the uptake of calcium, cadmium and zinc in Mytilus edulis have been studied. To separate direct from indirect effects of the inhibitors on metal uptake, their influence on the physiological condition of the mussels was also investigated. This was done by measuring clearance, respiration and excretion rates under the different exposure regimes and determining the scope for growth as an integrative index for physiological condition. The study has shown that the uptake of cadmium and zinc by Mytilus edulis can be modulated by calcium channel blockers and other inhibitors. The inhibitors also influenced physiological condition, but a significant correlation with the effects on metal uptake did not exist in most cases. Cadmium and zinc also inhibit each other's uptake, but the type of inhibition is not yet clear. The effects of the inhibitors on cadmium and zinc uptake are very different from the effects on calcium uptake, indicating that cadmium and zinc are preferentially taken up through other gateways. Overall, a significant degree of linear association is found between the effects of the inhibitors on the uptake of cadmium and zinc, suggesting common uptake routes. In addition, the effects of the calcium channel antagonist on the uptake of the metal ions are organ dependent, indicating that other types of channels are involved in the uptake of the metal ions in the gills and digestive system. Received: 16 February 1999 / Accepted: 23 September 1999  相似文献   

14.
选用我国北方地区近年来选育或推广应用的29个花生品种(系),采用全生育期内人工控水盆栽试验,设置正常供水(控制整个生育期土壤含水量为田间持水量的75%~80%)和中度干旱胁迫(控制土壤含水量为田间持水量的45%~50%)2个水分处理。收获后分析籽仁中铁、锌、锰、铝、镉等微量元素和钙、镁、钾、磷、氮等主要矿物质元素含量。结果表明,花生籽仁中铅、铬含量极低,未能检测出;品种间各微量和其他矿质元素含量均存在明显差异,微量元素中,铝平均含量最高,锰含量最低,铁和锌含量居中。干旱使花生籽仁中除铝之外的铁、锌、镉、锰微量元素含量显著增加,尤其是铁,其含量是浇水条件下的2.9倍,其次是镉,为浇水条件下的2.4倍,锌也达1.6倍;但干旱使籽仁中钙、镁含量降低,氮、磷、钾3元素的变化不大,两处理间差异不明显;两处理中除锌元素外其余矿质元素含量间的相关系数间均呈显著或极显著相关关系,镁、锰和镉三元素间的相关系数最大,均在0.95以上,钙次之,磷最小。表明土壤干旱可提高花生籽仁中铁、锌、镉、锰微量元素含量,且微量矿质元素协同效应明显;土壤湿润降低花生籽仁中磷、钾元素与其他矿质元素间的相关关系。  相似文献   

15.
Ground water quality in two well-developed cities of Haryana, viz. Hisar and Panipat was assessed for drinking purpose based on water quality parameters like pH, EC, turbidity, TDS, alkalinity, total hardness, calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), chloride (Cl), nitrate (NO3), phosphate (PO4), sulphate (SO4) and fluoride (F) with respect to different land-use areas viz. residential, industrial, commercial and agricultural. Water quality index based on 9 parameters showed that at Panipat, underground water in all the land-use zones was fit for consumption (WQI < 50), whereas at Hisar, water in agricultural areas was good in quality, but that in other areas varied in magnitude of pollution (WQI > 50 to 100).  相似文献   

16.
为了解微囊藻毒索在鲋鱼Carassius auratus L.体内生物富集作用,用LC/MS监测不同时间的鲋鱼肝脏、肌肉,以及饲养用水中痕量的微囊藻毒素.结果显示,肌肉组织中MC-RR和MC-LR的含量在18 d时达到峰值,分别为7.87 ng·g~(-1)和2.18 ng·g~(-1);而肝脏组织中MC-RR和MC-LR的含量在鲋鱼暴露9天时达到最高值,分别为25.30 ng·g~(-1)和33.27ng·g~(-1).研究结果支持肝脏组织是MCs的主要靶向器官,并且表明肝脏组织对MC-LR的富集量远大于MC-RR,而肌肉组织更易于积累MC-RR.文章还研究了鲋鱼体内的抗氧化酶(SOD、CAT、GST、GR酶)的活性变化,对MCs介导的氧化胁迫进行了评估.通过分别测定暴露不同时间点(3、9、18 d)肝脏和肌肉组织中的抗氧化酶的活性,发现它们的活性与组织中MCs的含量基本呈正相关,可能对MCs介导的氧化胁迫有缓解作用.以上表明,MCs能在鱼体内积累,抗氧化系统虽可缓解,但不能完全降解.因此食用被MCs污染的鱼类存在潜在的食品安全风险.  相似文献   

17.
Evaluation of Electrokinetic Remediation of Arsenic-contaminated Soils   总被引:1,自引:0,他引:1  
The potential of electrokinetic (EK) remediation technology has been successfully demonstrated for the remediation of heavy metal-contaminated fine-grained soils through laboratory scale and field application studies. Arsenic contamination in soil is a serious problem affecting both site use and groundwater quality. The EK technology was evaluated for the removal of arsenic from two soil samples; a kaolinite soil artificially contaminated with arsenic and an arsenic-bearing tailing-soil taken from the Myungbong (MB) gold mine area. The effectiveness of enhancing agents was investigated using three different types of cathodic electrolytes; deionized water (DIW), potassium phosphate (KH2PO4) and sodium hydroxide (NaOH). The results of the experiments on the kaolinite show that the potassium phosphate was the most effective in extracting arsenic, probably due to anion exchange of arsenic species by phosphate. On the other hand, the sodium hydroxide seemed to be the most efficient in removing arsenic from the tailing-soil. This result may be explained by the fact that the sodium hydroxide increased the soil pH and accelerated ionic migration of arsenic species through the desorption of arsenic species as well as the dissolution of arsenic-bearing minerals.  相似文献   

18.
弋良朋  王祖伟 《生态环境》2010,19(4):798-802
为了利用被镉污染的盐土,通过实验分析镉污染盐土中三种盐对油菜(Brassica napus)富集镉影响的差异性,探明不同类型镉污染盐土上种植油菜的植物修复效果。以镉超累积植物油菜为研究植物,通过温室盆栽土培试验,将油菜在含有不同质量分数盐(wS:0 g·kg^-1,2 g·kg^-1,4 g·kg^-1,6 g·kg^-1)的含镉(wCd:10 mg·kg^-1)土壤中培养60天,研究油菜对镉的生物富集因子、植株内地上部分和根部镉的质量分数变化。选择土壤中三种主要盐的类型,即氯化钠、硫酸钠和碳酸钠作为分析和研究对象。结果表明,含碳酸钠的土壤对油菜吸收镉有抑制作用,含硫酸钠的土壤对油菜吸收镉也有抑制作用,但效果没有碳酸钠的土壤大,含氯化钠的土壤对油菜吸收镉的影响不显著,只是在高质量分数时对油菜吸收镉有一些促进作用。在含不同类型盐的土壤中,不同土壤盐对油菜富集镉的能力也有显著的差异,土壤中氯化钠对油菜根部富集镉的能力没有显著影响,而对油菜地上部分富集镉的能力有一定的促进作用;土壤中的碳酸钠对油菜地上和地下部分富集镉的能力都有显著的抑制作用,不利于油菜对镉的富集。  相似文献   

19.
Uptake and loss of inorganic phosphate by Posidonia oceanica leaf tissue has been studied in in vitro experiments. Experimental data have shown that a steady state of inorganic phosphate uptake (about 40 nmol mg-1 dry wt.) is attained after 48 hours. in particular high accumulation (over 1000-fold the natural level in sea water) and slow loss (biological half-life, 65 days) of inorganic phosphate has been evaluated. Moreover the effect of three different metabolic inhibitors (sodium monovanadate, sodium azide, 2, 4-dinitrophenol) have been tested. Results of this effect and the high degree of inorganic phosphate accumulation in leaf tissue have demonstrated that inorganic phosphate carrier is energy dependent. Furthermore, the inorganic phosphate uptake is probably influenced by bivalent cations (Ca+2, Mg+2) but the mechanism is still uncertain.

Preliminary kinetic study has shown interesting results. in particular, km estimated value (2.8 μmol 1-1) has demonstrated the existence of a relatively high uptake rate (Vmax) at low DIP concentration while the kinetic study of inorganic phosphate loss from leaf tissues has shown a low value of the biological half life (about 60-70 days). This evidence could be significant for the existence of a complex distribution of inorganic phosphate in the leaf tissues.  相似文献   

20.
Concentrations of water, ash, protein, chitin, lipid, calcium, magnesium, sodium, potassium, strontium and copper were measured in individuals from a laboratory population of Antarctic krill, Euphausia superba Dana, over the course of a moult cycle. Significant changes in all variables were encountered. Total ash, lipid, calcium, magnesium and strontium all increased in concentration following moulting. Water, protein and copper concentrations all decreased following ecdysis and increased again towards the end of the moult cycle. The major ions sodium and potassium fluctuated around mean levels. Cast moults of E. superba were shown to be a drain on the ionic load of the krill, and the losses inherent in exuviation could account for much of the variation observed during the moult cycle.  相似文献   

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