title: Species-specific toxicity of ceria nanoparticles to Lactuca plants.
abstract: Species-specific differences in the toxicity of manufactured nanoparticles (MNPs) have been reported, but the underlying mechanisms are unknown. We previously found that CeO2 NPs inhibited root elongation of head lettuce, whereas no toxic effect was observed on other plants (such as wheat, cucumber and radish). In this study, interactions between Lactuca plants and three types of CeO2 NPs (lab-synthesized 7 and 25 nm CeO2 NPs, and a commercial CeO2 NPs) were investigated. It was found that CeO2 NPs were toxic to three kinds of Lactuca genus plants and different CeO2 NPs showed different degrees of toxicity. The results of X-ray absorption near edge fine structure indicate that small parts of CeO2 NPs were transformed from Ce(IV) to Ce(III) in roots of the plants that were treated with CeO2 NPs during the seed germination stage. But the high sensitivity of Lactuca plants to the released Ce(3+) ions caused the species-specific phytotoxicity of CeO2 NPs. Differences in sizes and zeta potentials among three types of CeO2 NPs resulted in their different degrees of biotransformation which accounted for the discrepancy in the toxicity to Lactuca plants. This study is among the few, and may indeed the first, that addresses the relation between the physicochemical properties of nanoparticles and its species-specific phytotoxicity.
authors.affiliation: Key Laboratory of Nuclear Analytical Techniques, Key Laboratory for Biological Effects of Nanomaterials and Nanosafety , Beijing , China and.
authors.forename: Peng
authors.initials: P
authors.lastname: Zhang
authors.forename: Yuhui
authors.initials: Y
authors.lastname: Ma
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Zhang
authors.forename: Xiao
authors.initials: X
authors.lastname: He
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Li
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.forename: Lirong
authors.initials: L
authors.lastname: Zheng
authors.forename: Yuliang
authors.initials: Y
authors.lastname: Zhao
mesh_terms: D002563:Cerium / Q000737:chemistry / Q000493:pharmacokinetics / Q000633:toxicity*; D018545:Lactuca / Q000737:chemistry / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D053768:Metal Nanoparticles / Q000737:chemistry / Q000633:toxicity*; D053758:Nanoparticles / Q000737:chemistry / Q000633:toxicity*; D018384:Oxidative Stress / Q000187:drug effects; D018517:Plant Roots / Q000737:chemistry / Q000187:drug effects / Q000254:growth & development; D018520:Plant Shoots / Q000737:chemistry / Q000187:drug effects / Q000254:growth & development; D013045:Species Specificity
chemical_list: D002563:Cerium; C030583:ceric oxide
keywords: Biotransformation; CeO2; Lactuca plants; nanoparticles; phytotoxicity