Wang Guohua, Ma Yuhui, Zhang Peng, He Xiao, Zhang Zhaohui, Qu Meihua, Ding Yayun, Zhang Junzhe, Xie Changjian, Luo Wenhe, Zhang Jing, Chu Shengqi, Chai Zhifang, Zhang Zhiyong
Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.
School of Public Health, University of South China, Hunan, 421001, China.
Environ Pollut. 2017 May;224:392-399. doi: 10.1016/j.envpol.2017.02.019. Epub 2017 Feb 22.
Fate and toxicity of manufactured nanoparticles (NPs) in the living organisms and the environment are highly related to their transformation. In the present study, the effect of phosphate on the phytotoxicity and transformation of CeO NPs was investigated in an agar medium using head lettuce plants that are sensitive to Ce ions. Plants were treated by CeO NPs with or without phosphate for 10 days. Results suggest that the treatments of P deficiency (P(-)) and CeO NPs (P(+)&Ce) could separately induce significant inhibition on the growth of lettuce seedlings and cause oxidative stress, but the inhibition was the most serious when the two conditions were combined (P(-)&Ce). In the absence of phosphate, more CeO NPs were transformed to Ce(III) in the roots and more Ce ions were translocated to the shoots, which induced higher toxicity to head lettuce. Phosphates could alleviate the phytotoxic effect of CeO NPs through the precipitation of dissociated Ce ions. Considering the wide existence of phosphate in the environment, phosphate-related transformation may be a critical factor in evaluating the toxicity and fate of many other metal-based NPs.
人造纳米颗粒（NPs）在生物体和环境中的命运及毒性与其转化密切相关。在本研究中，使用对铈离子敏感的生菜植株，在琼脂培养基中研究了磷酸盐对CeO NPs植物毒性和转化的影响。将植株用含或不含磷酸盐的CeO NPs处理10天。结果表明，缺磷（P(-)）和CeO NPs处理（P(+)&Ce）分别可显著抑制生菜幼苗生长并引起氧化应激，但两种情况同时存在时（P(-)&Ce）抑制最为严重。在无磷酸盐的情况下，更多的CeO NPs在根部转化为Ce(III)，更多的铈离子转运到地上部分，从而对生菜产生更高的毒性。磷酸盐可通过解离的铈离子沉淀来减轻CeO NPs的植物毒性作用。鉴于环境中磷酸盐广泛存在，与磷酸盐相关的转化可能是评估许多其他金属基纳米颗粒毒性和命运的关键因素。
