Du Jingjing, Zhang Yuyan, Liu Lina, Qv Mingxiang, Lv Yanna, Yin Yifei, Zhou Yinfei, Cui Minghui, Zhu Yanfeng, Zhang Hongzhong
School of Materials and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, PR China; Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, Zhengzhou University of Light Industry, Zhengzhou, PR China.
School of Materials and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, PR China.
Chemosphere. 2017 Nov;187:368-375. doi: 10.1016/j.chemosphere.2017.08.128. Epub 2017 Aug 25.
ZnO nanoparticles is one of the most used materials in a wide range including antibacterial coating, electronic device, and personal care products. With the development of nanotechnology, ecotoxicology of ZnO nanoparticles has been received increasing attention. To assess the phototoxicity of ZnO nanoparticles in aquatic ecosystem, microcosm experiments were conducted on Populus nigra L. leaf litter decomposition under combined effect of ZnO nanoparticles and visible light radiation. Litter decomposition rate, pH value, extracellular enzyme activity, as well as the relative contributions of fungal community to litter decomposition were studied. Results showed that long-term exposure to ZnO nanoparticles and visible light led to a significant decrease in litter decomposition rate (0.26 m vs 0.45 m), and visible light would increase the inhibitory effect (0.24 m), which caused significant decrease in pH value of litter cultures, fungal sporulation rate, as well as most extracellular enzyme activities. The phototoxicity of ZnO nanoparticles also showed impacts on fungal community composition, especially on the genus of Varicosporium, whose abundance was significantly and positively related to decomposition rate. In conclusion, our study provides the evidence for negatively effects of ZnO NPs photocatalysis on ecological process of litter decomposition and highlights the contribution of visible light radiation to nanoparticles toxicity in freshwater ecosystems.
氧化锌纳米颗粒是应用最为广泛的材料之一，其应用范围涵盖抗菌涂层、电子设备及个人护理产品等诸多领域。随着纳米技术的发展，氧化锌纳米颗粒的生态毒理学受到了越来越多的关注。为评估氧化锌纳米颗粒在水生生态系统中的光毒性，我们开展了微观实验，研究了在氧化锌纳米颗粒与可见光辐射共同作用下，黑杨树叶凋落物的分解情况。我们对凋落物分解速率、pH值、胞外酶活性以及真菌群落对凋落物分解的相对贡献进行了研究。结果表明，长期暴露于氧化锌纳米颗粒和可见光下会导致凋落物分解速率显著下降（从0.45米降至0.26米），且可见光会增强这种抑制作用（降至0.24米），这导致凋落物培养物的pH值显著下降，真菌孢子形成率以及大多数胞外酶活性也显著降低。氧化锌纳米颗粒的光毒性还对真菌群落组成产生了影响，尤其是对异孢菌属的影响，该属的丰度与分解速率呈显著正相关。总之，我们的研究为氧化锌纳米颗粒光催化对凋落物分解生态过程的负面影响提供了证据，并突出了可见光辐射对淡水生态系统中纳米颗粒毒性的作用。
