中文摘要：

以斑马鱼（Brachydanio rerio）为实验生物,采用半静态实验方法,研究了甲苯、乙苯和二甲苯的水生生态毒性效应.研究表明,水体中甲苯、乙苯和二甲苯对斑马鱼96h半致死浓度LC50分别为77.5、31.0和34.8mg·L^-1,根据化学物质对鱼类毒性分级标准,3种物质均属中等毒性,其毒性大小顺序为：乙苯〉二甲苯〉甲苯.在最高暴露浓度下,斑马鱼均出现了剧烈、无序游动,并伴有抽搐等现象,其中暴露在甲苯中的斑马鱼行为改变更为严重.分析认为,3种物质对斑马鱼毒性大小与疏/亲水性有关,疏水性越强,对水生生物的毒性作用越大.

英文摘要：

Aquatic ecotoxicological effects of toluene, ethylbenzene and xylene on zebrafish （Brachydanio rerio ） were investigated in this paper using the semi-static bioassay. Results indicated that the 96h LC50 values of the three chemicals acting on zebrafish were 77.5, 31.0 and 34.8mg.L^-1, respectively. According to the criteria for evaluating and grading toxicity of chemicals toxic to fishes, the toxicity of the three chemicals should be at the middle toxic level. The toxicity was in the sequence of ethylbenzene〉xylene〉tohiene. There were some abnormal behavioral changes including hyperactivity, erratic swimming and convulsions of zebrafish exposed to the three chemicals at the highest exposure levels, especially exposed to toluene. The further analysis showed that the toxicity of the three chemicals to zebrafish was closely related to the octanol-water coefficient of partition （Kow）. Chemicals with higher hydrophobicity induced higher aquatic toxicity to Brachydanio rerio.