Rafieepour Athena, R Azari Mansour, Khodagholi Fariba
Occupational Health Research Center, Department of Occupational Health, School of Public Health, 440827Iran University of Medical Sciences, Tehran, Iran.
Department of Occupational Health, School of Public Health and Safety, 216617Shahid Beheshti University of Medical Science, Tehran, Iran.
Toxicol Ind Health. 2023 Jan;39(1):23-35. doi: 10.1177/07482337221140644. Epub 2022 Nov 26.
Airborne crystalline silica (SiO) particles are one of the most common pollutants in stone industries. Limited studies have investigated the health effects of crystalline SiO nanoparticles. Hence, the objective of this study was to study the cytotoxicity of SiO in nano and micron sizes. A mineral quartz sample in the range of 0.2-0.8 mm sizes was purchased. These particles were ground at about 5 and 0.1 microns. Human cell line A549 was exposed to micro and nanometer particles at concentrations of 10, 50, 100, and 250 μg/ml for 24 and 72 h. Subsequently, the cytotoxicity of exposed cells was investigated by measuring cell survival, ROS generation, mitochondrial permeability, and intracellular glutathione content. The results showed that crystalline SiO nano and microparticles decreased cell survival, increased ROS generation, damaged the mitochondrial membrane, and lowered the antioxidant content of these cells in a concentration- and time-dependent manner. The toxicity of crystalline SiO microparticles at concentrations ≤50 μg/mL was greater than for nanoparticles, which was the opposite at concentrations ≥100 μg/mL. Exposure time and concentration were crucial factors for the cytotoxicity of exposed A549 cells to crystalline SiO particles, which can affect the severity of the effect of particle size. Due to the limitation of exposure concentration and test durations in this study, further studies on the parameters of nanoparticle toxicity and underlying mechanisms could advance our knowledge.
空气中的结晶二氧化硅（SiO）颗粒是石材行业最常见的污染物之一。仅有有限的研究调查了结晶SiO纳米颗粒对健康的影响。因此，本研究的目的是研究纳米级和微米级SiO的细胞毒性。购买了粒径在0.2 - 0.8毫米范围内的石英矿样品。将这些颗粒研磨至约5微米和0.1微米。人类细胞系A549分别在浓度为10、50、100和250μg/ml的情况下暴露于微米级和纳米级颗粒中24小时和72小时。随后，通过测量细胞存活率、活性氧生成、线粒体通透性和细胞内谷胱甘肽含量来研究暴露细胞的细胞毒性。结果表明，结晶SiO纳米颗粒和微米颗粒均以浓度和时间依赖性方式降低细胞存活率、增加活性氧生成、损伤线粒体膜并降低这些细胞的抗氧化剂含量。浓度≤50μg/mL时，结晶SiO微米颗粒的毒性大于纳米颗粒，而浓度≥100μg/mL时情况则相反。暴露时间和浓度是暴露的A549细胞对结晶SiO颗粒细胞毒性的关键因素，这可能会影响粒径效应的严重程度。由于本研究中暴露浓度和测试持续时间的限制，对纳米颗粒毒性参数及其潜在机制的进一步研究可能会增进我们的认识。
