Graphene oxides possess unique physicochemical properties with important potential applications in electronics, pharmaceuticals, and medicine. However, the toxicity following inhalation exposure to graphene oxide has not yet been clarified. Therefore, this study conducted a short-term graphene oxide inhalation toxicity analysis using a nose-only inhalation exposure system and male Sprague–Dawley rats. A total of four groups (15 rats per group) were exposed: (1) control (fresh air), (2) low concentration (0.76 ± 0.16 mg/m³), (3) moderate concentration (2.60 ± 0.19 mg/m³), and (4) high concentration (9.78 ± 0.29 mg/m³). The rats were exposed to graphene oxide for 6 h/day for 5 days, followed by recovery for 1, 3, and 21 days. No significant body or organ weight changes were noted after the short-term exposure or during the recovery period. Similarly, no significant systemic effects of toxicological importance were noted in the hematological assays, bronchoalveolar lavage fluid (BAL) inflammatory markers, BAL fluid cytokines, or blood biochemical assays following the graphene oxide exposure or during the post-exposure observation period. Moreover, no significant differences were observed in the BAL cell differentials, such as lymphocytes, macrophages, or polymorphonuclear cells. Graphene oxide-ingested alveolar macrophages as a spontaneous clearance reaction were observed in the lungs of all the concentration groups from post 1 day to post 21 days. Histopathological examination of the liver and kidneys did not reveal any significant test-article-relevant histopathological lesions. Importantly, similar to previously reported graphene inhalation data, this short-term nose-only inhalation study found only minimal or unnoticeable graphene oxide toxicity in the lungs and other organs.

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氧化石墨烯纳米板的短期吸入研究

氧化石墨烯具有独特的理化性质，在电子，制药和医药领域具有重要的潜在应用。但是，吸入氧化石墨烯后的毒性尚未弄清。因此，本研究使用仅鼻吸入暴露系统和雄性Sprague-Dawley大鼠进行了短期氧化石墨烯的吸入毒性分析。总共暴露四组（每组15只大鼠）：( 1）对照（新鲜空气），（2）低浓度（0.76±0.16 mg / m ³），（3）中等浓度（2.60±0.19 mg / m ³）和（4）高浓度（9.78±0.29 mg / m ³）。将大鼠暴露于氧化石墨烯6小时/天，持续5天，然后恢复1、3​​和21天。短期接触后或恢复期间未发现明显的体重或器官重量变化。同样，在氧化石墨烯暴露后或暴露后观察期间，血液学测定，支气管肺泡灌洗液（BAL）炎性标志物，BAL液细胞因子或血液生化测定均未观察到毒理学意义的重大全身性影响。此外，未观察到BAL细胞差异的显着差异，例如淋巴细胞，巨噬细胞或多形核细胞。从1天后到21天后，在所有浓度组的肺中都观察到了自发清除反应的氧化石墨烯吞噬的肺泡巨噬细胞。肝脏和肾脏的组织病理学检查未发现任何与试验物品相关的显着组织病理学病变。重要的是，类似于先前报道的石墨烯吸入数据，这项短期的仅鼻子吸入研究发现，在肺和其他器官中氧化石墨烯的毒性只有极小或不明显。