State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
Environ Sci Technol. 2022 Jan 4;56(1):403-413. doi: 10.1021/acs.est.1c02532. Epub 2021 Dec 20.
The use of commercial products containing engineered nanomaterials in realistic scenarios may lead to the accumulation of exogenous particles in brain tissues. In this study, we simulated the use of silver (Ag) nasal spray in humans using Sprague-Dawley rats at 0.04 mg/kg/day. Silver-containing particles were explicitly identified in the rat brain after the administration of nasal sprays containing colloidal Ag or silver ions (Ag) for 2 weeks using multiple methods. The accumulation of Ag-containing particles showed a delayed effect in different brain regions of the rats, with the mass concentration of particles increasing continuously for 1-2 weeks after the termination of administration. The size of the observed Ag-containing particles extracted from the brain tissues ranged from 18.3 to 120.4 nm. Further characterization by high-resolution transmission electron microscopy with energy-dispersive spectroscopy showed that the nanoparticles comprised both Ag and sulfur (S), with Ag/S atomic ratios of 1.1-7.1, suggesting that Ag-containing particles went through a series of transformations prior to or during their accumulation in the brain. Collectively, these findings provide evidence for the accumulation and transformation of Ag-containing particles in the rat brain, indicating a realistic risk to brain health resulting from the application of Ag-containing commercial products.
在实际场景中使用含有工程纳米材料的商业产品可能会导致外源性颗粒在脑组织中积累。在这项研究中，我们使用 0.04mg/kg/天的浓度，通过对 Sprague-Dawley 大鼠施用银（Ag）鼻喷雾剂来模拟人类使用含银纳米颗粒的鼻喷雾剂。在使用胶体 Ag 或银离子（Ag）鼻喷雾剂给药 2 周后，使用多种方法明确在大鼠脑中鉴定到了含银颗粒。含银颗粒的积累在大鼠的不同脑区呈现出延迟效应，在给药结束后 1-2 周内，颗粒的质量浓度持续增加。从脑组织中提取的观察到的含银颗粒的大小范围为 18.3-120.4nm。通过高分辨率透射电子显微镜和能量色散光谱的进一步表征表明，这些纳米颗粒包含 Ag 和硫（S），Ag/S 原子比为 1.1-7.1，表明含银颗粒在其在大脑中积累之前或期间经历了一系列转化。总的来说，这些发现为大鼠脑中含银颗粒的积累和转化提供了证据，表明由于使用含银商业产品，对大脑健康存在真实的风险。
