中国科学院海岸带环境过程与生态修复重点实验室知识库

随着纳米技术产业的高速发展,大量工程纳米颗粒物(Engineering nano-particles,ENPs)被排放到自然水环境中,因此对其进行生态毒性及环境风险的研究尤为迫切。综述了ENPs在水环境中的毒理学机理及理想模式生物筛选的研究进展。目前的研究表明ENPs的毒性作用机制主要包括两方面:一是影响细胞信号通路,二是氧化应激造成基因表达的变化。此外,光催化活性、细胞表面附着、溶解特性、表面特征、赋存形态、溶剂效应及与其他环境污染物的协同作用也是可能的毒性作用机理。模式生物的筛选与确定在纳米生态毒理学研究中极为重要。鱼类作为水环境中普遍存在的脊椎动物,群落庞大,其具有行为端点敏感性高、且在...

With the rapid development of nanotechnology industry, there is an increased discharge of engineered nano⁃ particles (ENPs) into aquatic environments; therefore, the study of their ecotoxicity and environmental risk is urgently required. This paper reviews the toxicological mechanisms of ENPs and the filter of model organisms. Researchers have pointed out two main traits of nanoparticle cytotoxicity: affection of cell signaling pathways and reactive oxygen species (ROS)⁃related changes in gene expression. Oxidative stress caused by ROS production inside cells can change the levels of anti⁃oxidative enzymes, and then destroy the balance between oxidation and anti⁃oxidation. Thus, cells are damaged by ROS accumulation, leading to a series of consequences, such as lipid oxidation and inhibited cell growth. Previous studies havesuggested that photosensitivity of ENPs and their ROS production under high⁃intensity light with specific wavelengths may be related to their ENP toxicity. The adsorption of ENPs on the surface of microorganisms or cells can hinder their normal physiological functions; in addition, the adsorption of ENPs can also enhance the absorption of hazardous substances in microorganisms or cells. Since the toxicity testing conditions of ENPs may vary, and there is no uniform requirement for solvent type and use; therefore, toxicity research of ENPs is not based on the same principles. In the ecotoxicological assessment of ENPs, the effects of solvents should be taken into consideration, and it is necessary to assess whether other substances will produce toxicity under the influence of ENPs. In addition, solubility, surface characteristics, forms of metal oxides are also important toxicological mechanisms of ENPs. In nano⁃ecological toxicology studies, the filter and determination of optimal model organisms is vital. It has been widely demonstrated and recommended that fish should be considered as a primary model animal for the evaluation of the potential acute aquatic toxicity of ENPs. Fish are the most dominant vertebrates in the aquatic environments. Fish demonstrate high sensitivity of behavior endpoint and obvious concentration⁃response relationship in bio⁃toxicity experiments. Therefore, fish are considered to be the most suitable model organism in aquatic ecotoxicological research. A few studies have shown that behavioral endpoints of developing fish are more effective in detecting toxicity of ENPs compared to traditional studies such as embryonic development and fatality rate. It is emphasized that in ecotoxicological research of ENPs, further aquatic invertebrate testing will be of great significance, particularly studies on bioaccumulation and chronic endpoints with long⁃term low exposure. Bivalves represent an ideal group for studying the effects of ENPs, since they are abundant in both freshwater and marine aquatic environments. In addition, phytoplankton are important producers in aquatic environments, occupying an important place in aquatic ecosystems. Toxic effects of ENPs to phytoplankton and saving of ENPs by phytoplankton can directly or indirectly affect the entire aquatic ecosystem. Invertebrates and phytoplankton are both dominant in aquatic environments, and are highly sensitive to pollutants; they have significant enrichment and amplification effect on harmful substances. Therefore, they also have a certain advantage as model organisms.