Copper oxide (II) nanoparticles (CuO-NPs) have been increasingly used in products of human interest, such as coating for food packaging and wood protection. The main objective of this study was to evaluate in vivo acute toxicity of CuO-NPs after oral exposure and compare it with CuO microparticles (CuO-MPs). Female rats were orally exposed, through gavage procedure, to the analyzed materials. After 14 days of observation, hematological, biochemical, histopathological, and copper organ accumulation analyses were performed. CuO-NPs (25.17 ± 8 nm) and CuO-MPs (1.092 ± 0.52 μm) were characterized and compared regarding their acute oral toxicity. Animals treated with CuO-NPs at the dose of 2000 mg kg⁻¹ presented changes in feces and copper hepatic accumulation. Histopathological exam of livers demonstrated hepatocyte binucleation and megalocytosis. None of the animals tested with CuO-MPs showed any alterations. Oral exposure to CuO-NPs, at the dosage of 2000 mg kg⁻¹, may cause mild transitory liver damage, mainly resolved during a 14-day post-exposure period. Also, the nanoparticulated material showed to be more toxic than the microparticulated one.

中文翻译：

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口服暴露于氧化铜（II）纳米和微粒后14天的Wistar大鼠器官的急性毒性和铜积累的评估

氧化铜（II）纳米粒子（CuO-NPs）已越来越多地用于人类感兴趣的产品，例如食品包装涂料和木材保护。这项研究的主要目的是评估口服暴露后CuO-NP的体内急性毒性，并将其与CuO微粒（CuO-MPs）进行比较。通过管饲法将雌性大鼠口服暴露于所分析的材料。观察14天后，进行了血液学，生化，组织病理学和铜器官堆积分析。对CuO-NPs（25.17±8 nm）和CuO-MPs（1.092±0.52μm）进行表征并比较其急性口服毒性。用2000 mg kg ^-1剂量的CuO-NP治疗的动物表现出粪便和肝铜积累的变化。肝脏的组织病理学检查显示肝细胞双核化和巨细胞增多。用CuO-MPs测试的动物均未显示任何变化。口服暴露于2000 mg kg ^-1的CuO-NPs可能会引起轻度的暂时性肝损伤，主要在暴露后14天即可解决。而且，纳米微粒材料显示出比微粒微粒更大的毒性。