Abstract
Background Cerium oxide nanoparticles (CeO 2 NPs) are widely used in various commercial applications because of their characteristic properties. CeO 2 NPs can be easily exposed to humans in real life, but the safety assessment of CeO 2 NPs has not been fully investigated. Therefore, in this study, we conducted a combined repeated-dose and reproductive/developmental toxicity screening study to investigate the potential effects on general health hazards, including reproductive/developmental functions, after repeated CeO 2 NPs oral exposure. In addition, tissues from parental animals and their pups were collected to analyze the internal accumulation of cerium. CeO 2 NPs were orally administered to Sprague-Dawley rats at doses of 0, 100, 300 and 1000 mg/kg during their pre-mating, mating, gestation and early lactation periods. Results In the general systemic and reproductive/developmental examinations, no marked toxicities were observed in any of in-life and terminal observation parameters in this study. In the biodistribution analysis, cerium was not detected in either parental or pup tissues (blood, liver, lungs and kidneys). Conclusion Repeated oral exposure of CeO 2 NPs did not induce marked toxicities affecting general systemic and reproductive/developmental functions up to the dose level of 1000 mg/kg and the CeO 2 NPs were not systemically absorbed in parental animals or their pups. This result could be used to risk assessment for human, and additional toxicity studies with CeO 2 NPs will be necessary considering various physicochemical properties and exposure probabilities of this nanoparticles.
Intratracheal instillation of cerium oxide nanoparticles induces hepatic toxicity in male Sprague-Dawley rats