State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210046, China.
State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210046, China.
J Hazard Mater. 2017 Apr 5;327:64-70. doi: 10.1016/j.jhazmat.2016.12.044. Epub 2016 Dec 26.
Concerns about the environmental safety of metal-based nanoparticles (MNPs) in aquatic ecosystems are increasing. Simultaneously, elevated atmospheric CO levels are a serious problem worldwide, making it possible for the combined exposure of MNPs and elevated CO to the ecosystem. Here we studied the toxicity of nZnO to goldfish in a water-sediment ecosystem using open-top chambers flushed with ambient (400±10μL/L) or elevated (600±10μL/L) CO for 30days. We measured the content of Zn in suspension and fish, and analyzed physiological and biochemical changes in fish tissues. Results showed that elevated CO increased the Zn content in suspension by reducing the pH value of water and consequently enhanced the bioavailability and toxicity of nZnO. Elevated CO led to higher accumulation of Zn in fish tissues (increased by 43.3%, 86.4% and 22.5% in liver, brain and muscle, respectively) when compared to ambient. Elevated CO also intensified the oxidative damage to fish induced by nZnO, resulting in higher ROS intensity, greater contents of MDA and MT and lower GSH content in liver and brain. Our results suggest that more studies in natural ecosystems are needed to better understand the fate and toxicity of nanoparticles in future CO levels.
人们越来越关注金属基纳米粒子（MNPs）在水生生态系统中的环境安全性。同时，大气中 CO 水平的升高是一个全球性的严重问题，这使得 MNPs 和升高的 CO 同时暴露于生态系统成为可能。在这里，我们使用开顶式气室在 30 天内用环境（400±10μL/L）或升高（600±10μL/L）的 CO 冲洗水-沉积物生态系统，研究了 nZnO 对金鱼的毒性。我们测量了悬浮液和鱼体内的 Zn 含量，并分析了鱼组织的生理和生化变化。结果表明，升高的 CO 通过降低水的 pH 值来减少悬浮液中的 Zn 含量，从而提高了 nZnO 的生物利用度和毒性。与环境相比，升高的 CO 导致鱼组织中 Zn 的积累更高（肝脏、大脑和肌肉分别增加了 43.3%、86.4%和 22.5%）。升高的 CO 还加剧了 nZnO 对鱼的氧化损伤，导致肝脏和大脑中的 ROS 强度更高、MDA 和 MT 含量更大以及 GSH 含量更低。我们的结果表明，未来需要在自然生态系统中进行更多的研究，以更好地了解纳米颗粒在未来 CO 水平下的归宿和毒性。
