Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Department of Architectural Engineering, East University of Heilongjiang, Harbin 150066, China.
Sci Total Environ. 2019 Oct 15;687:71-76. doi: 10.1016/j.scitotenv.2019.05.476. Epub 2019 Jun 1.
Increasing applications of engineered nanomaterials lead to the release of nanoparticles into various environmental media, especially soil. However, the environmental behavior of nano ZnO in soil and the toxic mechanism to terrestrial invertebrates were not fully understood. In this study, the concentrations of nano ZnO in earthworms (Eisenia fetida) were measured to assess its bioaccumulation. The ratio of nano ZnO in earthworms to soil in 250 mg/kg treatment group was lower than that in 10 mg/kg treatment group as the earthworms would not take up too much nano ZnO to protect themselves from the damage. Combination of in-vivo and in-vitro tests was adapted to investigate the toxic mechanism of nano ZnO to earthworms. In in-vivo test, biomarkers including ROS, SOD, and MDA suggested that the toxic effects of nano ZnO to earthworms were caused by the oxidative stress. To further elucidate its toxic mechanism, in-vitro toxicity test was carried out by employing earthworm coelomocytes. The biomarkers, intracellular ROS, extracellular LDH, and cell viability showed concentration-dependent manner with nano ZnO in the culture media, demonstrating that in-vitro toxicity test could be utilized to reveal the toxic mechanism of nano ZnO to earthworms or other organisms.
随着工程纳米材料应用的增加，纳米颗粒被释放到各种环境介质中，特别是土壤中。然而，纳米 ZnO 在土壤中的环境行为及其对陆地无脊椎动物的毒性机制尚不完全清楚。在本研究中，测量了蚯蚓（赤子爱胜蚓）体内纳米 ZnO 的浓度，以评估其生物累积性。在 250mg/kg 处理组中，蚯蚓体内纳米 ZnO 与土壤的比例低于 10mg/kg 处理组，因为蚯蚓不会吸收太多的纳米 ZnO 来保护自己免受损伤。本研究采用体内和体外试验相结合的方法，研究了纳米 ZnO 对蚯蚓的毒性机制。在体内试验中，ROS、SOD 和 MDA 等生物标志物表明，纳米 ZnO 对蚯蚓的毒性作用是由氧化应激引起的。为了进一步阐明其毒性机制，采用蚯蚓体腔细胞进行了体外毒性试验。生物标志物，包括细胞内 ROS、细胞外 LDH 和细胞活力，均表现出与培养基中纳米 ZnO 的浓度依赖性，表明体外毒性试验可用于揭示纳米 ZnO 对蚯蚓或其他生物的毒性机制。
