School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Environ Sci Pollut Res Int. 2019 Nov;26(31):31752-31762. doi: 10.1007/s11356-019-06229-0. Epub 2019 Sep 4.
The increasing trend of nanoparticle usage in science and technology has led to significant human exposure. Occupational exposure to iron oxides and silica dust has been reported in mining, manufacturing, construction, and pharmaceutical operations. The combined toxicological effects of nanoparticles and simultaneous exposure to other compounds have given rise to a new concern. Hence, the objective of this study was to investigate the toxicological effects of magnetite and polymorphous silicon dioxide nanoparticles in single and combined exposures. The polymorphous silicon dioxide nanoparticles were obtained from the milled quartz particles under 100 nm in diameter. The milled particles were purified through chloric and nitric acid wash processes. The toxic effects of the magnetite nanoparticles were investigated independently and in combination with quartz using the A cell line for durations of 24 and 72 h, and using diverse concentrations of 10, 50, 100, and 250 μg/mL. MTT, ROS, mitochondrial membrane potential, and cell glutathione content assays were used to evaluate the amount of cell damage in this study. The statistical significance level in one-way ANOVA and independent t test was considered to be at the 5% confidence level. The size and purity of polymorphous silicon dioxide nanoparticles were measured by TEM and ICP-OES analysis, respectively. The particles' diameters were under 100 nm and demonstrated a purity of higher than 99%. The toxicity results of this study showed a dependency on concentration and exposure duration in reducing the cell viability, cellular glutathione content, and mitochondrial membrane potential, as well as increasing the ROS generation in single and combined exposures with magnetite and polymorphous silicon dioxide nanoparticles. The toxic effects of combined exposure to these nanoparticles were less than the single exposures, and statistically significant antagonistic interactions were detected. Combined exposure to polymorphous silicon dioxide and magnetite nanoparticles, in comparison with their single exposures, could affect health in an antagonistic manner. Since this study has been the first of its kind, further studies investigating the health effects of single and combined exposures to these compounds are needed to verify our findings. Generally, studies such as this one could contribute to the field of combined toxicity effects.
纳米粒子在科学和技术中的应用呈增长趋势，这导致人类的暴露量显著增加。在采矿、制造、建筑和制药作业中，已经有报道称职业性接触氧化铁和二氧化硅粉尘。纳米粒子的联合毒性作用以及同时接触其他化合物引起了新的关注。因此，本研究的目的是研究单种和混合暴露于磁铁矿和多晶态二氧化硅纳米粒子的毒理学效应。多晶态二氧化硅纳米粒子是通过直径在 100nm 以下的研磨石英颗粒获得的。通过氯和硝酸洗涤过程对研磨颗粒进行了纯化。使用 A 细胞系，在 24 和 72 小时的时间内，使用浓度分别为 10、50、100 和 250μg/mL 的不同浓度，独立和组合使用磁铁矿纳米粒子研究了多晶态二氧化硅纳米粒子的毒性作用。MTT、ROS、线粒体膜电位和细胞谷胱甘肽含量测定用于评估本研究中的细胞损伤量。在单向方差分析和独立 t 检验中，统计显著性水平被认为是在 5%置信水平。通过 TEM 和 ICP-OES 分析分别测量了多晶态二氧化硅纳米粒子的尺寸和纯度。颗粒的直径小于 100nm，纯度高于 99%。本研究的毒性结果表明，在单一和混合暴露于磁铁矿和多晶态二氧化硅纳米粒子时，细胞活力、细胞谷胱甘肽含量和线粒体膜电位降低，ROS 生成增加，这与浓度和暴露时间有关。这些纳米粒子联合暴露的毒性作用小于单一暴露，并且检测到统计学上显著的拮抗相互作用。与单一暴露相比，多晶态二氧化硅和磁铁矿纳米粒子的联合暴露可能以拮抗方式影响健康。由于本研究是首例，因此需要进一步研究这些化合物的单一和联合暴露对健康的影响，以验证我们的发现。一般来说，像这样的研究可以为联合毒性效应领域做出贡献。
