Cu2+和Cd2+对斑马鱼胚胎早期发育的联合毒性

采用斑马鱼胚胎早期发育技术，测定Cu2+和Cd2+ 2种重金属对胚胎发育的毒性效应. 以24 h致死和72 h胚胎孵化抑制为毒性终点，2种重金属的剂量-效应曲线可用Weibull函数或Logit函数有效描述，由最佳拟合函数计算得出半数致死浓度(LC₅₀)或半数效应浓度(EC₅₀)为毒性效应的评价标准，2个毒性终点的重金属毒性大小顺序均为Cu2+>Cd2+. 应用浓度加和(CA)与独立作用(IA)2种模型，对72 h孵化抑制率的无观测效应浓度(NOEC)配比混合物的联合毒性作用进行了预测，通过混合物试验观测数据的95%置信区间与CA模型和IA模型预测的剂量-效应曲线进行比较分析表明，2种模型都可以有效预测斑马鱼胚胎孵化的联合毒性. 

Joint Toxicity of Cu2+ and Cd2+ to Early Development of Zebrafish Embryos

The toxicities of two heavy metals Cu²⁺ and Cd²⁺ to embryo development were determined using the zebrafish embryo early development toxicity technique. The dose-response curves of the two heavy metals could be effectively characterized by the Logit and Weibull functions on the two toxicity endpoints of 24 h lethal rate and 72 h hatch inhibition rate. The median lethal concentration (LC₅₀) and the median effect concentration (EC₅₀) calculated by the best-fitted functions were used as the toxicity evaluation criteria. The toxicity order of the two heavy metals on the two observed toxicity endpoints according to the value of either LC₅₀ or EC₅₀ both showed that Cu²⁺>Cd²⁺. The joint toxicity was predicted using the mixture ratio of the non-observed effect concentration (NOEC) of 72 h hatch inhibition rate by two models of concentration addition (CA) and independent action (IA), then compared with the 95% confidence intervals of the mixture experimental data. The results indicated that the two models could both predict joint toxicity of zebrafish embryo hatching effectively.