The advancement of nanotechnology has increased use of nanoparticles in industrial scale. Among the most used nanoparticles are those silver-based. Large-scale use can raise levels of these nanoparticles in aquatic environments, which, in turn, presents potential risks to aquatic organisms and ecosystems, causing undesired environmental impacts. To evaluate the potential risk of the silver nanoparticles (AgNPs) interaction with plants, seeds of Lactuca sativa L. (Asteraceae) were exposed to different concentrations of AgNPs (12.5, 25, 50, 100 ppm), using the percentage of germinated seeds and morphological changes in the root as toxicity criterion. Only at the maximum concentration of AgNPs (100 ppm), there is a negative effect on root growth in relation to the positive control (distilled water). These negative effects may be related to the production of reactive oxygen species (ROS) caused by the dissolution of Ag0 in Ag+. Other concentrations had a positive effect on root growth, although not significant. Scanning electron microscopy (SEM) images showed morphological changes in the root surface exposed to the concentration of 100 ppm of AgNPs, resulting in root deformation. The accumulation of silver nanoparticles (AgNPs) was observed using transmission electron microscopy (TEM). AgNPs were found in the vacuoles, cell wall, middle lamella and cytoplasm, individualised or forming agglomerates. These results broaden our understanding of the safe levels of nanoparticle use and its impact on the environment. In addition, the nanoparticles used in this study can be used in new product development, since the observed maximum safe amount.

中文翻译：

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银纳米粒子对莴苣（Lactuca sativa）萌发和根发育的毒性作用

纳米技术的进步增加了纳米颗粒在工业规模上的使用。其中最常用的纳米颗粒是那些银基的。大规模使用会提高这些纳米粒子在水生环境中的含量，进而给水生生物和生态系统带来潜在风险，造成不良环境影响。为了评估银纳米粒子 (AgNPs) 与植物相互作用的潜在风险，将莴苣（菊科）的种子暴露于不同浓度的 AgNPs（12.5、25、50、100 ppm），使用发芽种子的百分比和根的形态变化作为毒性标准。只有在最大浓度的 AgNPs (100 ppm) 下，才会对与阳性对照（蒸馏水）相关的根生长产生负面影响。这些负面影响可能与 Ag0 在 Ag+ 中溶解引起的活性氧 (ROS) 的产生有关。其他浓度对根生长有积极影响，但不显着。扫描电子显微镜 (SEM) 图像显示，暴露于 100 ppm AgNPs 浓度的根表面发生形态变化，导致根变形。使用透射电子显微镜 (TEM) 观察银纳米粒子 (AgNPs) 的积累。AgNPs 存在于液泡、细胞壁、中层和细胞质中，呈个体化或形成团块。这些结果拓宽了我们对纳米颗粒使用安全水平及其对环境影响的理解。此外，本研究中使用的纳米粒子可用于新产品开发，因为观察到的最大安全量。