硝基苯对斑马鱼细胞DNA的损伤

DNA damage induced by nitrobenzene in histiocyte of zebrafish(Danio rerio)

硝基苯是重要的人造化工原料,人类的生产和生活使其可能成为水体和环境的污染源。为了解硝基苯对水产动物可能的致毒作用,采用单细胞凝胶电泳(SCGE)方法检测了不同浓度硝基苯染毒后的斑马鱼肝胰脏、肾脏、鳍条表皮和精子细胞DNA的损伤情况。当硝基苯的处理剂量在国家地表水环境质量标准(GB3838-2002)时(0.017 mg/L),对斑马鱼肝胰脏、肾脏和精子细胞DNA的损伤不明显,分别为30%、33%和44%,与对照组相比差异不显著(P>0.05);在同样浓度下,鳍条表皮细胞DNA受损率则高达69%。当硝基苯的浓度高于国家地表水环境质量标准时,可引起斑马鱼肝胰脏、肾脏、鳍条表皮和精子细胞DNA的严重损伤。处理剂量为0.106 mg/L时,其受损率分别为48%、62%、61%、82%;0.213 mg/L时分别为42%、87%、76%、56%;在0.425 mg/L时分别为52%、87%、75%、75%;在0.850 mg/L时分别为58%、95%、93%、85%;在1.700 mg/L时分别为62%、90%、99%、83%,以上各处理组与空白对照相比差异显著(P<0.05)。实验结果表明,当水环境中硝基苯的浓度低于国家地表水环境质量标准时,对斑马鱼的体细胞及精子细胞没有明显的毒性作用;硝基苯的浓度高于国家地表水环境质量标准时,对斑马鱼体细胞和精子细胞具有较强的毒害作用,且细胞DNA的受损率随着硝基苯剂量的增加而增加,并呈现一定的剂量损伤效应。因此,渔业水质标准中硝基苯的浓度不应高于国家地表水环境质量标准。

Nitrobenzene is an important chemical raw material. Owing to human activities of production and living, it may become the pollution source of the water and the environment. In order to understand the possible toxicity of nitrobenzene to aquatic animals, the DNA damage of the nitrobenzene was studied at different concentrations to the liver and pancreas, kidney, fin, sperm cell of zebrafish by single-cell gel electrophoresis technique. When the treatment dose of nitrobenzene was at the national standard for surface water environmental quality（ GB3838 -2002, 0.017 mg/L）, the DNA damage of the liver and pancreas, kidney and sperm cell was not obvious, being 30%, 33% and 44% respectively. The results were no significant difference compared with the control group （ P 〉 0. 05）. In the same concentration, the DNA damage rate was as high as 69% for epidermal cells of fins. When the concentration of nitrobenzene was higher than the national standard, it caused the serious DNA damage to the liver and pancreas, kidney and sperm cell. When the concentration of nitrobenzene was 0. 106, the damage rates were 48% ,62% ,61%, 82% ;at 0.213 mg/L those were 42% ,87% ,76% ,56% ; those were 52% ,87% ,75% ,75% at 0.425 mg/ L; those were 58% ,95% ,93% ,85% at 0.850 rag/L; those were 62% ,90% ,99% ,83% at 1. 700 mg/L respectively. All the treatments concentration above the national standard were significant differences compared with the control group （P 〈 0.05 ）. The result showed that the nitrobenzene had no obvious toxicity to the somatic cells and the sperm cells of the zebra：fish when the concentration of nitrobenzene in the water environment was lower than the national standard. When the concentration of nitrobenzene was higher than the national standard, the nitrobenzene had stronger toxic effect on the somatic cells and the sperm cells of the zebrafish, and the DNA damage rate rose with the nitrobenzene dose increasing, and it presented the specific dose of the damage effect. So the concentration of nitrobenzene in fishery water standard should not be higher than the national standard.