Cerium oxide (CeO2), one of many engineered nanomaterials (ENMs), is composed primarily of metal oxides, such as cerium oxide (CeO2). CeO2-containing materials are widely used as a polishing agent for glass mirrors, plate glass, television tubes, ophthalmic lenses, and precision optics. The widespread use of this nanomaterial (NM) resulted in increased environmental contamination levels and consequent human exposure. However, the influence of Ce on humans remains to be determined. The aim of this study was to expose female ICR mice to varying nanoparticle sizes of 35 nm, 300 nm as well as a mixture of 1-5 µM CeO2 particles through intranasal (i.n.) instillation at 40 mg/kg dose on day 1, 3 and 5, and the experiment terminated on day 7. Histopathology findings demonstrated that hydropic degeneration was prominently associated with hemorrhage in renal cortex and medulla in all CeO2-administered groups. In liver of CeO2-exposed mice, hydropic degeneration was also prominent. Serum chemistries also indicated signs of renal and hepatic lesion as evidenced by significantly decreased serum levels of total bilirubin (TBIL) and total phosphate (TP) and activity of alkaline phosphatase (ALP). ICP-MS analysis group demonstrated that Ce levels were not significantly higher in liver and kidneys of mice exposed to 35 nm CeO2. An increase in Ce content was observed in hepatic and renal tissues of mice exposed to 300 nm or 1-5 µM CeO2. The levels of Ce were similar in these two groups suggesting a threshold level of Ce was attained regardless of NP size. Data thus demonstrated that i.n. instillation of different-sized CeO2 particles translocated to liver and kidney and that size difference of CeO2 particles did not exert significant in the observed histopathology responses.

中文翻译：

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鼻内滴入不同大小的二氧化铈（CeO2）颗粒的易位性：对小鼠的潜在不良影响。

氧化铈（CeO2）是许多工程纳米材料（ENM）之一，主要由金属氧化物（例如氧化铈（CeO2））组成。含CeO2的材料被广泛用作玻璃镜，平板玻璃，电视管，眼镜片和精密光学器件的抛光剂。这种纳米材料（NM）的广泛使用导致环境污染水平提高，并因此导致人体暴露。然而，铈对人类的影响尚待确定。这项研究的目的是在第1、3天以40 mg / kg剂量通过鼻内滴入，将雌性ICR小鼠暴露于35 nm，300 nm的不同纳米颗粒以及1-5 µM CeO2颗粒的混合物中。和5，实验在第7天终止。组织病理学结果表明，在所有CeO2给药组中，水样变性与肾皮质和髓质出血明显相关。在暴露于CeO2的小鼠肝脏中，水样变性也很突出。血清化学成分还表明有肾脏和肝脏病变的迹象，血清总胆红素（TBIL）和总磷酸盐（TP）的水平明显降低，碱性磷酸酶（ALP）的活性明显降低。ICP-MS分析组证明，暴露于35 nm CeO2的小鼠的肝脏和肾脏中Ce含量没有明显升高。在暴露于300 nm或1-5 µM CeO2的小鼠的肝和肾组织中，Ce含量增加。两组中Ce的水平相似，这表明无论NP大小如何，都可以达到Ce的阈值水平。因此，数据表明