Laboratory of Nuclear Instrumentation, Center of Nuclear Energy in Agriculture, University of São Paulo, Avenida Centenário, 303, Piracicaba, São Paulo, 13416000, Brazil.
School of Engineering, University of Guelph. Thornbrough Building, 50 Stone Rd E, Guelph, Ontario, N1G 2W1, Canada.
Chemosphere. 2021 Jun;273:128492. doi: 10.1016/j.chemosphere.2020.128492. Epub 2020 Oct 12.
This study evaluated the uptake and translocation of cerium nanoparticles (CeO NPs) and soluble Ce(NO) by soybean plants (Glycine max L. Merrill) under the whole plant life-cycle and relevant environmental concentrations, 0.062 and 0.933 mg kg, which represent maximal values for 2017 in agricultural soils and sludge treated soils, respectively. The experiments were carried out using a nutrient solution. Cerium was detected in the soybean roots epidermis and cortex, leaves, and grains, but it neither impaired plant development nor grain yield. The concentration of Ce in the shoot increased as a function of time for plants treated with Ce(NO), while it remained constant for plants treated with CeO NPs. It means that CeO NPs were absorbed in the same rate as biomass production, which suggests that they are taken up and transported by water mass flow. Single-particle inductively coupled plasma mass spectrometry revealed clusters of CeO NPs in leaves of plants treated with 25 nm CeO NPs (ca. 30-45 nm). The reprecipitation of soluble cerium from Ce(NO) within the plant was not confirmed. Finally, bioconcentration factors above one were found for the lowest concentrated treatments. Since soybean is a widespread source of protein for animals, we draw attention to the importance of evaluating the effects of Ce entrance in the food chain and its possible biomagnification.
本研究评估了全生命周期条件下，在与环境浓度相关的条件下，即分别代表 2017 年农业土壤和处理过的污泥中最大值的 0.062 和 0.933mg/kg，大豆植株（Glycine max L. Merrill）对铈纳米颗粒（CeO NPs）和可溶性铈（Ce(NO)）的吸收和转运。实验采用营养液进行。铈在大豆根表皮和皮层、叶片和籽粒中被检测到，但它既没有损害植物发育也没有降低籽粒产量。用 Ce(NO)处理的植株中，Ce 在地上部分的浓度随时间的增加而增加，而用 CeO NPs 处理的植株中 Ce 浓度保持不变。这意味着 CeO NPs 的吸收速度与生物质产量相同，这表明它们是通过水流被吸收和运输的。单颗粒电感耦合等离子体质谱显示，用 25nm CeO NPs 处理的植株叶片中存在 CeO NPs 簇（约 30-45nm）。没有确认 Ce(NO)中的可溶性铈在植物内重新沉淀。最后，在最低浓度处理中发现了生物浓缩因子大于 1。由于大豆是动物蛋白质的广泛来源，我们提请注意评估 Ce 进入食物链的影响及其可能的生物放大的重要性。
