State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun 130117, China.
State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun 130117, China.
Ecotoxicol Environ Saf. 2018 Dec 15;165:153-159. doi: 10.1016/j.ecoenv.2018.08.091. Epub 2018 Sep 5.
The continuous and single pulses exposure of Cu, Zn, Pb and Cd on larvae Brachymystax lenok were tested in this study. The first-order kinetics was employed to obtain better comprehension on the time-toxicity relationship of tested heavy metals in continuous exposure test. For difference in time-varying exposure or recovery, 50% lethal time-averaged concentration (TAC) was used to assess the pulsed toxicity, which took both time and concentration into consideration in exposure and post-exposure period. TAC assessment to the single pulses and the regression analysis of first-order kinetic to continuous exposures demonstrated that Cu and Zn showed greater toxicity than Pb and Cd, indicating a slower uptake and/or depuration effect for zinc or copper. Furthermore, the results showed that recovery effect of larvae to all four metals was found in 24 h exposure followed by 72 h in fresh water, while for 72 h exposure and 24 h non-exposure the delayed lethal phenomenon occurred.
本研究测试了 Cu、Zn、Pb 和 Cd 对白斑狗鱼幼鱼的连续和单次脉冲暴露。采用一级动力学方程来更好地理解连续暴露试验中测试重金属的时间-毒性关系。对于时变暴露或恢复的差异，使用 50%致死时间平均浓度（TAC）来评估脉冲毒性，该毒性在暴露和暴露后期间同时考虑了时间和浓度。对单次脉冲的 TAC 评估和对连续暴露的一级动力学的回归分析表明，Cu 和 Zn 的毒性大于 Pb 和 Cd，表明锌或铜的吸收和/或清除效果较慢。此外，结果表明，在暴露 24 小时后再在新鲜水中暴露 72 小时，所有四种金属的幼鱼都能恢复，而在暴露 72 小时后再非暴露 24 小时，会出现延迟致死现象。
