Predicting the survival of zebrafish larvae exposed to fluctuating pulses of lead and cadmium
Predicting the survival of zebrafish larvae exposed to fluctuating pulses of lead and cadmium
复制标题
预测暴露于波动的铅和镉脉冲的斑马鱼幼虫的存活率
DOI：
10.1016/j.chemosphere.2019.02.102
复制
发表时间：
2019-05-01
期刊：
影响因子：
8.8
通讯作者：
Zhu, Lin
中科院分区：
文献类型：
--
作者：
Chen, Min;Gao, Yongfei;Zhu, Lin
水生生物经常暴露于随时间变化的污染物浓度，由于脉冲输入在自然水体中。传统的毒理学实验通常是在恒定的暴露模式下进行的，这与实际环境不一致。采用改进的毒代动力学-毒代动力学（TK-TD）模型，研究了铅和镉分别在2、4和6 h三种脉冲暴露条件下对斑马鱼仔稚鱼的毒性效应。参数敏感性分析表明，J（M），（max）对模型的输出影响最大。在相同的时间加权平均（TWA）浓度下，Cd或Pb脉冲暴露导致的死亡率低于恒定暴露。铅、镉脉冲间隔6 h处理的幼虫存活率高于脉冲间隔2 h和4 h处理。Cd或Pb持续暴露的毒性大于2、4和6 h脉冲暴露，这是因为Cd或Pb在体内的累积浓度大于脉冲暴露。随机死亡模型比个体耐受模型更适合于预测铅镉脉冲暴露下幼虫的存活率，其R-2（0.670-0.940）大于个体耐受模型（0.588-0.861）。我们的模型提供了实验室毒性测试的方法和建模方法，以解决重金属脉冲暴露的毒性。(C)2019爱思唯尔有限公司版权所有。
Aquatic organisms are often exposed to time-varied concentrations of contaminants due to pulsed inputs in natural water. Traditional toxicology experiments are usually carried out in a constant exposure pattern, which is inconsistent with the actual environment. In this study, a refined toxicokinetic-toxicodynamic (TK-TD) model was used to study the toxic effects of Pb and Cd on zebrafish larvae under three pulse exposures with 2, 4, and 6 h, respectively. The parameter sensitivity analysis showed that J(M), (max) had the greatest impact on the output of the model. Cd or Pb pulse exposure resulted in less death than constant exposure at the same time-weighted average (TWA) concentrations. Survival fraction in larvae under 6 h interval between two pulses of Pb or Cd was larger than that under 2 h and 4 h interval. Toxicity under constant exposure of Cd or Pb was greater than that under 2, 4, and 6 h interval pulse exposure because the cumulative Cd or Pb concentration in the body under constant exposure was greater than that under pulse exposure. The results also showed that the stochastic death (SD) model was more suitable than the individual tolerance (IT) model for predicting the survival fraction of larvae under pulse exposure to Pb and Cd, which was indicated by higher R-2 (0.670-0.940) in SD model than that (0.588-0.861) in IT model. Our model provides approaches for laboratory toxicity testing and modeling approaches for addressing the toxicity of heavy metal pulsed exposure. (C) 2019 Elsevier Ltd. All rights reserved.