title: Nano-CeO2 exhibits adverse effects at environmental relevant concentrations.
abstract: Ceria nanoparticles (nano-CeO(2)), due to their widespread applications, have attracted a lot of concern about their toxic effects on both human health and the environment. The present work aimed to evaluate the in vivo effects of nano-CeO(2) (8.5 nm) on Caenorhabditis elegans (C. elegans) at environmental relevant concentrations (molar concentrations ranging from 1 nM to 100 nM). The results indicate that nano-CeO(2) could induce ROS accumulation and oxidative damage in C. elegans, and finally lead to a decreased lifespan. The most surprising thing is that the mean lifespan of nematodes was significantly decreased by 12% even at the exposure level of 1 nM (p < 0.01). In vitro tests suggest that the ability of nano-CeO(2) to catalyze ROS generation was involved in the mechanism for its toxicity to C. elegans. To our best knowledge, this is the first case in which nanoparticles exhibit adverse effects on organisms at such low concentrations (1nM-100 nM). So, our findings indicate the importance of nanotoxicological investigations at environmentally relevant concentrations and will attract more attentions on the risks of NPs exposure.
authors.affiliation: Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Key Laboratory of Nuclear Analytical Techniques, Institute of High Energy Physics, Chinese Academy of Sciences , Beijing 100049, China.
authors.forename: Haifeng
authors.initials: H
authors.lastname: Zhang
authors.forename: Xiao
authors.initials: X
authors.lastname: He
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Zhang
authors.forename: Peng
authors.initials: P
authors.lastname: Zhang
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Li
authors.forename: Yuhui
authors.initials: Y
authors.lastname: Ma
authors.forename: Yashu
authors.initials: Y
authors.lastname: Kuang
authors.forename: Yuliang
authors.initials: Y
authors.lastname: Zhao
authors.forename: Zhifang
authors.initials: Z
authors.lastname: Chai
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000187:drug effects* / Q000378:metabolism; D002563:Cerium / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D004785:Environmental Pollutants / Q000633:toxicity*; D053768:Metal Nanoparticles / Q000633:toxicity*; D018384:Oxidative Stress; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D004785:Environmental Pollutants; D017382:Reactive Oxygen Species; D002563:Cerium; C030583:ceric oxide