Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; Sino-Danish College, University of Chinese Academy of Sciences, Beijing 100049, China.
Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.
Ecotoxicol Environ Saf. 2022 Sep 1;242:113939. doi: 10.1016/j.ecoenv.2022.113939. Epub 2022 Aug 2.
The potential toxicity and ecological risks of rare-earth nanoparticles in the environment have become a concern due to their widespread application and inevitable releases. The integration of hydroponics experiments, partial least squares structural equation modeling (PLS-SEM), and Transmission Electron Microscopy (TEM) were utilized to investigate the physiological toxicity, uptake and translocation of yttrium oxide nanoparticles (YO NPs) under different hydroponic treatments (1, 5, 10, 20, 50 and 100 mg·L of YO NPs, 19.2 mg·L Y(NO) and control) in tomato (Lycopersicon esculentum) seedlings. The results indicated that YO NPs had a phytotoxic effect on tomato seedlings' germination, morphology, physiology, and oxidative stress. The YO NPs and soluble Y reduced the root elongation, bud elongation, root activity, chlorophyll, soluble protein content and superoxide dismutase and accelerated the proline and malondialdehyde in the plant with increasing concentrations. The phytotoxic effects of YO NPs on tomato seedlings had a higher phytotoxic effect than soluble Y under the all treatments. The inhibition rates of different levels of YO NPs in shoot and root biomass ranged from 0.2% to 6.3% and 1.0-11.3%, respectively. The bioaccumulation and translocation factors were less than 1, which suggested that YO NPs significantly suppressed shoot and root biomass of tomato seedlings and easily bioaccumulated in the root. The observations were consistent with the process of concentration-dependent uptake and translocation factor and confirmed by TEM. YO NPs penetrate the epidermis, enter the cell wall, and exist in the intercellular space and cytoplasm of mesophyll cells of tomato seedlings by endocytic pathway. Moreover, PLS-SEM revealed that the concentration of NPs significantly negatively affects the morphology and physiology, leading to the change in biomass of plants. This study demonstrated the possible pathway of YO NPs in uptake, phytotoxicity and translocation of YO NPs in tomato seedlings.
由于稀土纳米颗粒在环境中的广泛应用和不可避免的释放，其潜在的毒性和生态风险已成为人们关注的焦点。本研究采用水培实验、偏最小二乘结构方程建模（PLS-SEM）和透射电子显微镜（TEM）相结合的方法，研究了不同水培处理（1、5、10、20、50 和 100 mg·L 的氧化钇纳米颗粒（YO NPs）、19.2 mg·L Y（NO）和对照）下 YO NPs 在番茄（Lycopersicon esculentum）幼苗中的生理毒性、吸收和转运。结果表明，YO NPs 对番茄幼苗的萌发、形态、生理和氧化应激有明显的毒性作用。YO NPs 和可溶 Y 降低了根伸长、芽伸长、根活力、叶绿素、可溶性蛋白含量和超氧化物歧化酶，并随着浓度的增加加速了脯氨酸和丙二醛的积累。在所有处理条件下，YO NPs 对番茄幼苗的毒性作用均高于可溶 Y。不同浓度 YO NPs 对地上部和根部生物量的抑制率分别为 0.2%6.3%和 1.0%11.3%。生物积累和转运因子均小于 1，表明 YO NPs 显著抑制了番茄幼苗地上部和根部生物量，容易在根部积累。这些观察结果与浓度依赖性吸收和转运因子的过程一致，并通过 TEM 得到证实。YO NPs 通过内吞途径穿透表皮，进入细胞壁，存在于番茄幼苗的细胞间隙和细胞质中。此外，PLS-SEM 表明，纳米颗粒浓度显著负影响形态和生理，导致植物生物量的变化。本研究证实了 YO NPs 在番茄幼苗中吸收、毒性和转运的可能途径。
