印染尾水复合暴露对斑马鱼的慢性毒性效应

Study of Chronic Toxic Effects on Zebrafish(Danio rerio) Resulted from Combined Exposure to Textile Effluents

印染工业飞速发展产生了大量的污废水,印染尾水进入水体后会导致水生态系统的毒性积累,危及水生生物的生存及人类安全。为了探究印染尾水长期暴露的复合慢性毒性效应,该研究在建立模拟水生态系统的基础上,以斑马鱼作为研究对象,测定了死亡率、基本生长参数以及斑马鱼肌肉与肠道组织样品中过氧化氢酶(CAT)活性、谷胱甘肽(GSH)含量、谷胱甘肽过氧化物酶(GSH-Px)活性、丙二醛(MDA)含量、超氧化物歧化酶(SOD)活力和总抗氧化能力(T-AOC)等生长、生理和免疫学指标。结果表明:印染尾水长期暴露造成斑马鱼体重减轻,肝脏功能受损,死亡率显著提高,生理生化指标异常,肌肉和肠道组织中CAT、MDA高于对照组,而GSH、GSH-Px、SOD、T-AOC低于对照组,其中,肠道中SOD显著低于对照组,肌肉中GSH-Px活性显著低于对照组,印染废水中污染物破坏了机体抗氧化系统的动态平衡,导致机体抗氧化能力下降1/6左右。

With the rapid development of printing and dyeing industry, a large amount of wastewater has been produced and discharged into water bodies, and toxic contaminants contained in the wastewater have been accumulated in the aquatic ecosystem causing ecological risks menacing human-being’s safety. In order to probe into the combined chronic toxic effects of long-term exposure to textile effluents, a simulated aquatic ecosystem was set up, zebrafish(Danio rerio) being taken as a study object. The study included calculating mortality and basic growth parameters, dissecting the muscle and intestinal tissues of zebrafish, and analyzing the activities of catalase(CAT), glutathione(GSH), glutathione peroxidase(GSH-Px), malondialdehyde(MDA), superoxide dismutase(SOD) and total antioxidant capacity(T-AOC) for the physiological and immunological responses. The study revealed that zebrafish got weight-loss, liver damage, increasing mortality, and becoming abnormal in terms of physiology and biochemistry after being exposed to textile effluents. Further investigation showed that CAT and MDA in muscle and intestine were higher than those in the control group, while GSH, GSH-Px, SOD and T-AOC were lower than those in the control group;GSH-Px activities in intestine and muscle were significantly lower than control group. Eventually, the dynamic balance of the antioxidant system in zebrafish were undermined by the long-term exposure of textile effluents, which led to a decrease of about one sixth of the antioxidant capacity.