中文摘要：

目的研究不同混合关系下甲酚异构体对斑马鱼的联合毒性效应。方法采用等毒性单位比的方法进行了对甲酚、间甲酚和邻甲酚二元、三元混合物的斑马鱼联合毒性试验并应用毒性单位分析法和相加指数法对其联合毒性效应进行评价。结果对甲酚与间甲酚的联合毒性24h内为协同作用，48h为相加作用，72h和96h又表现为协同作用；对甲酚＋间甲酚＋邻甲酚组的联合毒性在24h内为拮抗作用，24h之后联合毒性作用类型由拮抗作用转变为协同作用。结论甲基酚类化合物随着混合物中化合物种类增加和染毒时间的延长，联合毒性作用呈增强趋势。

英文摘要：

Purposes--To study the joint toxicity effects between different mixture of cresol isomers on Zebrafish（Brachydanio rerio）. Methods--Toxicity experiments with Zebrafish have been conduc- ted and joint toxicity effects of the equitoxic binary mixtures and ternary mixtures of cresol isomers were assessed by the methods of toxicity unit（TU） and additional index（AI） respectively. Results The joint toxicity of p-cresol and m-cresol was synergistic at 24 h, 72 h, 96 h, but additive at 48 h. And the joint toxicity of p-cresol, m-cresol and o-cresol was antagonistic effect before 24 h, and syner- gistic effect after 24 h. Conclusion-The joint toxicity effects enhanced with the increasing of the com- pounds in the mixture and the extension of the exposure time.