【作者】 方静杰；

【导师】 范兆廷；

【作者基本信息】 东北农业大学 ， 动物遗传育种与繁殖， 2008， 硕士

【摘要】 硝基苯(Nitrobenzene,NB)的分子式为C6H5NO2,分子量为123.06,是重要的化工原料,广泛应用于国防、印染、塑料、农药和医药工业,全世界每年排入环境中的硝基苯类化合物约为1万吨,是环境中主要的有机污染物之一。NB具有弱致突变性,长期接触对人体及动植物危害极大,现已被我国国家环保局列为水中优先控制的有机污染物,美国环保局(EPA)也规定NB为环境中优先监测污染物。随着化工业的迅速发展,硝基苯越来越多地进入渔业水域,在我国松花江中游硝基苯检出率较高,过量的硝基苯排入水体,会引起水质恶化,影响鱼类的生存,破坏水生生态系统,还可以在生物体内富集,危害人类健康。本文以NB为研究对象,采用实验室模拟胚胎孵化及单细胞凝胶电泳技术,研究了NB对鲢、鳙胚胎发育所产生的影响和NB对斑马鱼肝胰脏、肾脏、鱼鳍、精子细胞DNA损伤作用,并对NB的作用机理进行了初步探讨。研究结果表明:1.暴露于不同浓度硝基苯处理组的鲢胚胎表现出与对照组不同的死亡率及畸形率,以及发育的延迟。随着硝基苯浓度的增加,鲢胚胎的死亡率及畸形率呈上升趋势,当暴露浓度>0.85 mg?L-1时,鲢胚胎的死亡率达到100 %。硝基苯浓度为0.017~0.425 mg?L-1时,胚胎发育分别延迟3~16 h,而暴露于浓度为0.85 mg?L-1以及1.7 mg?L-1中的鲢胚胎在32h全部死亡。2.暴露于不同浓度硝基苯处理组的鳙胚胎表现出与对照组不同的死亡率及畸形率,以及发育的延迟。随着硝基苯浓度的增加,鳙胚胎的死亡率及畸形率呈上升趋势,当暴露浓度>0.85mg?L-1时,鳙胚胎的死亡率达到100%。硝基苯浓度为0.017~0.425 mg?L-1时,胚胎发育分别延迟4~8 h。而暴露于浓度为0.85 mg?L-1以及1.7 mg?L-1中的鳙胚胎在25 h全部死亡。3.硝基苯在一定浓度范围内对斑马鱼肝胰脏(0.106~1.7 mg?L-1)、肾脏(0.017~1.7 mg?L-1)、鱼鳍(0.017~1.7 mg?L-1)、精子(0.106~1.7 mg?L-1)细胞DNA产生了损伤作用,且细胞的平均彗尾长度(损伤度)及受损率随硝基苯浓度的升高而升高,损伤细胞分布随着浓度的升高,由0、1级损伤细胞占优势转变为2、3级损伤细胞占优势。综上所述,NB可以引起鲢、鳙胚胎发育的延迟,并可导致胚胎在发育中死亡和畸形的产生。对斑马鱼的肝胰脏、肾脏、鱼鳍、精子细胞也可引起DNA的损伤,表现出遗传毒性。更多还原

【Abstract】 Nitrobenzene, C6H5NO2, is an important chemical raw material and widely used in national defense, dyeing and printing, plastics, pesticides and pharmaceutical industry. There is about 10,000 tons nitrobenzene compounds discharged into the environment each year in the world, is one of the major organic pollutants now. NB is weak mutagenicity that long-term exposure to humans and plants and animals will result in great harm. With the rapid development of the chemical industry, more and more nitrobenzene was discharged into the middle reaches of the Songhua River in China, cause deterioration of water quality and affect the aquatic ecosystems, also enriched in the organism and may be endanger to human health.This paper selected contaminant nitrobenzene (NB) as resaerch object, use laboratory simulation of embryos hatching and single-cell gel electrophoresis technique, studied the effect of NB on the silver carp, bighead carp embryonic development and DNA damage of the zebrafish liver and pancreas, kidney, fin, sperm cell. Moreover, this paper tried to probe into the effect mechanism of NB. Which provided the basis for the fully estimate of ecological toxicology on aquatic organism. The results showed that:1. Silver carp embryos that exposed to different concentrations of nitrobenzene compare to the control group showed different mortality and abnormality rate, and development was delayed. With increasing concentration of nitrobenzene, embryo mortality and abnormality rate upward trend, when exposed concentration> 0.85 mg?L-1, mortality reached 100%. embryonic development delayed for 3 to 16 h at the concentration of 0.017 ~ 0.425 mg?L-1, and embryos were all dead at 32 h exposure to the concentration of 0.85 mg?L-1 and 1.7 mg?L-1 .2. Bighead carp embryos that exposed to different concentrations of nitrobenzene compare to the control group showed different mortality and deformity rate, and development was delayed too. With increasing concentration of nitrobenzene, embryo mortality and abnormality rate upward trend, when exposed concentration> 0.85 mg?L-1, mortality reached 100%. embryonic development delayed for 4 to 8 h at the concentration of 0.017 ~ 0.425 mg?L-1, and embryos were all dead at 25 h exposure to the concentration of 0.85 mg?L-1 and 1.7 mg?L-1 .3. Certain concentration of nitrobenzene induced DNA damage on cell of zebrafish liver and pancreas (0.106 ~ 1.7 mg?L-1), kidney (0.017 ~ 1.7 mg?L-1), fins (0.017 ~ 1.7 mg?L-1), sperm (0.106 ~ 1.7 mg?L-1). Injured cells and the average tail length increased with the concentration of nitrobenzene. Distribution of cell changed with the increase of concentration, 0,1grade damage cell dominant into 2,3 grade damage cell dominant.Sum up, NB can make silver, bighead carp embryonic development delay, and may result in the development of fetal death and abnormality fries. NB also induced DNA damage on the liver and pancreas, kidney, fin, sperm cells of Zebrafish, showed genetic toxicity.更多还原