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在LAS和AE单一毒物对彭泽鲫的毒性实验的基础上,研究了Cu-LAS、Zn-LAS、Cu-AE、Zn-AE四种组合的复合污染对彭泽鲫的毒性效应。结果表明,LAS的毒性大于AE的毒性;Cu、Zn均能增强表面活性剂的毒性作用,促进作用为Cu〉Zn;Cu对表面活性剂的促进作用表现出一定的规律性,随浓度的升高表面活性剂的毒性增强;但Zn对表面活性剂的毒性影响的规律性仍不明确。 相似文献
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Under the indoor simulant conditions, toxic effects of crude-oil-contaminated soil which was put into aquatic environment on the young fishes Carassius auratus and their hepatic antioxidant system after a 20-d exposure were investigated. Results showed that the relationship between the mortality of C. auratus and the exposed doses could be divided into 3 phases: fishes exposed to the low dose groups (0.5-5.0 g/L) were dead due to the ingestion of crude-oil-contaminated soils in aquatic environment; at the m... 相似文献
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Oxidative stress parameters and some antioxidant defense systems in the liver of Carassius auratus exposed to glyphosate and its formulation (Roundup®) have been studied. Fish were exposed to glyphosate and its formulation at concentrations of 0.032, 0.16, 0.8, and 4.0 mg L?1, all calculated on glyphosate basis, for 11 days. Hydroxyl radical generation as determined by electron spin resonance spectroscopy of its spin-adduct with α-phenyl-t-butyl nitrone increased with the concentration of Roundup®. Superoxide dismutase activities were decreased relative to control by 21%–46% when exposed to glyphosate and 45%–52% when exposed to Roundup®, suggesting that the formulation is more toxic than glyphosate alone. Catalase showed no difference between both groups. 相似文献
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在室内模拟条件下,研究了水体中不同浓度石油污染土壤暴露20d对鲫鱼(Carassius auratus)幼体死亡率和肝脏抗氧化系统的影响.结果表明,鲫鱼死亡率随其暴露浓度的变化明显分为3个部分:低浓度(0.5~5.0g·L-1)摄食死亡,中等浓度(5.0~25.0g·L-1)吸收死亡,高浓度(25.0~50.0g·L-1)胁迫死亡.1.0g·L-1浓度组死亡率最高,死亡速率最快;50.0g·L-1浓度组在暴露后期死亡速率迅速升高.鲫鱼肝脏中谷胱甘肽硫转移酶(GST)、过氧化氢酶(CAT)和超氧化物歧化酶(SOD)的活性可被显著诱导,具体表现为:在所设浓度范围内,幼体鲫鱼肝脏GST活性均受到显著激活,0.5g·L-1浓度下,GST活性被最大程度诱导,达到对照组的606%;SOD活性先升高后降低,10.0g·L-1时酶活性最强,50.0g·L-1浓度下活性被显著抑制;CAT活性于0.5g·L-1就被显著诱导,2.5g·L-1浓度是对照组的4.86倍.可以认为,鲫鱼肝脏SOD和CAT,尤其GST活性对水体中石油污染土壤较敏感,均可作为水生生态系统中石油污染存在的早期检测指标. 相似文献
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研究了2-氯-4-硝基苯胺、4-氯-3-硝基苯胺,2-氯-5-硝基苯胺对斑马鱼的急性毒性,96hLC50分别为6.99,2.58,8.63mg/L,为阐明氯化硝基苯胺类化合物对水生生物抗氧化酶的早期影响,将鲫鱼暴露于梯度浓度的2-氯-4-硝基苯胺,4-氯-3-硝基苯胺,2-氯-5-硝基苯胺中,研究鲫鱼血清SOD和GSH-PX活性短期(48h)内的变化,研究结果表明,在实验设置浓度下,随着暴露浓度升高,与空白对照组相比,3种化合物对SOD活性表现为先轻微激活后抑制,对GSH-PX活性先激活再抑制后有所回升,表明3种化合物对鲫鱼血清SOD和GSH-PX活性有显著影响,与3种化合物96hLC50相比,引起生化效应的暴露浓度明显降低,且反应快速,可考虑SOD和GSH-PX酶活性相结合作为该类化合物对水环境污染胁迫的敏感生物指示物。 相似文献
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在重金属离子的暴露作用下,鲫鱼DNA总甲基化水平发生变化.结果表明,Cu、Zn、Pb、Cd及其混合重金属离子极大地提高了鲫鱼肝脏DNA的总甲基化水平;Cu、Zn两种生物元素对DNA总甲基化水平的改变要小于Pb、Cd两种非生物元素;随着混合重金属离子浓度的增加,鲫鱼肝脏DNA的总甲基化水平也有所增高;混合重金属离子对不同组织DNA总甲基化水平的影响不同,肝脏>鱼鳃>肾脏.重金属离子作用下的鲫鱼组织DNA总甲基化水平改变是其产生基因毒性作用的另一种机制. 相似文献
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Ting Li Qixing Zhou Ning Zhang Yi Luo 《Journal of environmental science and health. Part. B》2013,48(8):638-643
Under laboratory conditions, ecotoxicological effects of chlorpromazine (CPZ) on freshwater goldfish (Carassius auratus) were examined using the toxic culture experiment. The results showed that the median lethal concentration (LC50) of CPZ toxic to Carassius auratus in 24, 48 and 96 h was 1.11, 0.43 and 0.32 mg/L, respectively. Thus, CPZ is an extreme toxicant to goldfish. Furthermore, there were significantly positive correlations between the ecotoxicological effects of CPZ and its concentrations, and the toxicity became higher as the exposure time increased. The activity of superoxide dismutase (SOD) and catalase (CAT) in goldfish livers was significantly influenced by CPZ. At the same exposure time, the activity of SOD reduced first, and increased then, whereas the activity of CAT enhanced first and decreased then. At the same exposure levels of CPZ, the activity of SOD and CAT changed similarly, decreased first, then increased and decreased at last. Within the range of exposure concentrations, the changes in the activity of CAT can more easily reflect the oxidation stress in Carassius auratus by CPZ than those of SOD. 相似文献