title: Effects of rare earth oxide nanoparticles on root elongation of plants.
abstract: The phytotoxicity of four rare earth oxide nanoparticles, nano-CeO(2), nano-La(2)O(3), nano-Gd(2)O(3) and nano-Yb(2)O(3) on seven higher plant species (radish, rape, tomato, lettuce, wheat, cabbage, and cucumber) were investigated in the present study by means of root elongation experiments. Their effects on root growth varied greatly between different nanoparticles and plant species. A suspension of 2000 mg L(-1) nano-CeO(2) had no effect on the root elongation of six plants, except lettuce. On the contrary, 2000 mg L(-1) suspensions of nano-La(2)O(3), nano-Gd(2)O(3) and nano-Yb(2)O(3) severely inhibited the root elongation of all the seven species. Inhibitory effects of nano-La(2)O(3), nano-Gd(2)O(3), and nano-Yb(2)O(3) also differed in the different growth process of plants. For wheat, the inhibition mainly took place during the seed incubation process, while lettuce and rape were inhibited on both seed soaking and incubation process. The fifty percent inhibitory concentrations (IC(50)) for rape were about 40 mg L(-1) of nano-La(2)O(3), 20mg L(-1) of nano-Gd(2)O(3), and 70 mg L(-1) of nano-Yb(2)O(3), respectively. In the concentration ranges used in this study, the RE(3+) ion released from the nanoparticles had negligible effects on the root elongation. These results are helpful in understanding phytotoxicity of rare earth oxide nanoparticles.
authors.affiliation: Key Laboratory for Bio-Environmental 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: Yuhui
authors.initials: Y
authors.lastname: Ma
authors.forename: Linglin
authors.initials: L
authors.lastname: Kuang
authors.forename: Xiao
authors.initials: X
authors.lastname: He
authors.forename: Wei
authors.initials: W
authors.lastname: Bai
authors.forename: Yayun
authors.initials: Y
authors.lastname: Ding
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Zhang
authors.forename: Yuliang
authors.initials: Y
authors.lastname: Zhao
authors.forename: Zhifang
authors.initials: Z
authors.lastname: Chai
mesh_terms: D029741:Brassica rapa / Q000187:drug effects / Q000254:growth & development; D004305:Dose-Response Relationship, Drug; D018545:Lactuca / Q000187:drug effects / Q000254:growth & development; D053768:Metal Nanoparticles / Q000633:toxicity* / Q000648:ultrastructure; D008674:Metals, Rare Earth / Q000633:toxicity*; D018517:Plant Roots / Q000187:drug effects* / Q000254:growth & development; D012989:Soil Pollutants / Q000633:toxicity*; D014908:Triticum / Q000187:drug effects / Q000254:growth & development
chemical_list: D008674:Metals, Rare Earth; D012989:Soil Pollutants