中文摘要：

以螺旋鱼腥藻（Anabaena spiroides）为实验材料，采用每天测定数据，连续跟踪10d的方法，研究了甲基叔丁基醚（Methyl tert-butyl ether，MTBE）与雌二醇对螺旋鱼腥藻的单一毒性以及在不同毒性单位配比下的联合毒性。选用毒性单位（TU）、相加指数（AI）、混合毒性指数（MTI）和毒性增大指数（TEI）进行联合毒性评价．结果表明。MTBE与雌二醇共存时，在实验周期（10d）内，其联合作用方式基本表现为协同作用．此外，MTBE和雌二醇的单一毒性和联合毒性数据随着培养时间的变化而产生剧烈变化，毒性数据在培养时间3～7d比较平稳，在4～5d最佳．

英文摘要：

In order to determine the joint toxicities of MTBE and estradiol to Anabaena spiroides in different toxic unit ratio, 10-day tests were employed and the data were determined every day. Toxicity Unit （TU）, Additive Index （AI）, Mixture Toxicity Index （MTI） and Toxicity Enhancement Index （TEI）were used to evaluate the joint toxicities. Results showed that the mixture of MTBE and estradiol occurred synergism in the periods of experimentation. Moreover, the single and joint toxicities of MTBE and estradiol varied drastically with the culture time. The data were suitable on the third to seventh day, and the optimum time emerged on the fourth to fifth day.