Yan Liqing, Feng Mingbao, Liu Jiaoqin, Wang Liansheng, Wang Zunyao
State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, PR China.
State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, PR China.
Ecotoxicol Environ Saf. 2016 Mar;125:61-71. doi: 10.1016/j.ecoenv.2015.11.036. Epub 2015 Dec 4.
With the increasing applications of carbon nanotubes (CNTs) worldwide, considerable concerns have been raised regarding their inevitable releases into natural waters and ecotoxicity. It was supposed that CNTs may interact with some existing pollutants like zinc in aquatic systems and exhibit different effects when compared with their single treatments. However, data on their possible combined toxicity on aquatic species are still lacking. Moreover, the interactions of Zn with different functionalized CNTs may be distinct and thereby lead to diverse results. It is like that functional groups play a vital role in illustrating the differences in toxicity among various CNTs. In this study, the single and joint effects of multi-walled carbon nanotubes (MWCNTs) and two MWCNTs functionalized with carboxylation (COOH-MWCNTs) or hydroxylation (OH-MWCNTs) in the absence or presence of zinc (Zn) on antioxidant status and histopathological changes in Carassius auratus were evaluated. Synergistic effect was tentatively proposed for joint-toxicity action, which was supported by apparently observed oxidative stress and histopathological changes in joint exposure groups. The integrated biomarker response index was calculated to rank the toxicity order, from which the conclusion of synergistic effect was strengthened. Regarding differences among various CNTs, our data showed that OH-MWCNTs and COOH-MWCNTs were more stressful to fish than raw MWCNTs. This finding sustained that functionalization is an important factor in nanotoxicity, which may serve as clues for future design and application of CNTs. Overall, these results provided some valuable toxicological data on the joint effects of CNTs and heavy metals on aquatic species, which can facilitate further understanding on the potential impacts of other coexisting pollutants in the culture of freshwater fish.
随着碳纳米管（CNTs）在全球范围内的应用日益增加，人们对其不可避免地释放到天然水体中以及生态毒性产生了相当大的关注。据推测，碳纳米管可能会与水生系统中一些现有的污染物（如锌）相互作用，并且与单一处理相比会表现出不同的影响。然而，关于它们对水生物种可能的联合毒性的数据仍然缺乏。此外，锌与不同功能化碳纳米管的相互作用可能不同，从而导致不同的结果。似乎官能团在说明各种碳纳米管之间的毒性差异方面起着至关重要的作用。在本研究中，评估了多壁碳纳米管（MWCNTs）以及用羧基化（COOH-MWCNTs）或羟基化（OH-MWCNTs）功能化的两种多壁碳纳米管在有或没有锌（Zn）存在的情况下对鲫鱼抗氧化状态和组织病理学变化的单一和联合影响。初步提出联合毒性作用存在协同效应，联合暴露组中明显观察到的氧化应激和组织病理学变化支持了这一点。计算了综合生物标志物反应指数以对毒性顺序进行排名，由此强化了协同效应的结论。关于各种碳纳米管之间的差异，我们的数据表明，OH-MWCNTs和COOH-MWCNTs对鱼类的压力比未处理的MWCNTs更大。这一发现支持了功能化是纳米毒性的一个重要因素，这可能为碳纳米管未来的设计和应用提供线索。总体而言，这些结果提供了一些关于碳纳米管和重金属对水生物种联合影响的有价值的毒理学数据，这有助于进一步了解淡水鱼养殖中其他共存污染物的潜在影响。
