Department of Chemistry and CESAM, University of Aveiro, 3810-193 Aveiro, Portugal; Department of Chemistry and CICECO, Aveiro Institute of Nanotechnology, University of Aveiro, 3810-193 Aveiro, Portugal.
Department of Chemistry and CESAM, University of Aveiro, 3810-193 Aveiro, Portugal.
Chemosphere. 2015 Oct;136:86-94. doi: 10.1016/j.chemosphere.2015.04.054. Epub 2015 May 15.
Release of engineered nanoparticles (ENPs) to soil is well documented but little is known on the subsequent soil-pore water distribution of ENPs once present in soil. In this study, the availability and mobility of silver (Ag) and gold (Au) ENPs added to agricultural soils were assessed in two separate pot experiments. Pore water samples collected from pots from day 1 to 45 using porous (<0.17 μm) membrane samplers suggest that both Ag and Au are retained almost completely within 24 h with less than 13% of the total added amount present in pore water on day 1. UV-Vis and TEM results showed that AuENPs in pore water were present as both homoaggregates and heteroaggregates until day 3 after which the concentration in pore water was too low to detect the presence of aggregates. A close relation between the concentration of Au and Fe in pore water suggests that the short term solubility of Au is partly controlled by natural soil colloids. Results suggest that under normal aerated soil conditions the actual availability of Ag and AuENPs is low which is relevant in view of risk assessment even though the impact of environmental conditions and soil properties on the reactivity of ENPs (and/or large ENPs aggregates) retained in the solid matrix need to be addressed further.
将工程纳米粒子（ENPs）释放到土壤中已有充分的记录，但对于一旦存在于土壤中，ENPs 随后在土壤-孔隙水中的分布情况知之甚少。在这项研究中，通过两个独立的盆栽实验评估了添加到农业土壤中的银（Ag）和金（Au）ENPs 的有效性和迁移性。使用多孔（<0.17μm）膜采样器从第 1 天到第 45 天从盆中采集的孔隙水样品表明，Ag 和 Au 在 24 小时内几乎完全被保留，第 1 天只有不到 13%的总添加量存在于孔隙水中。UV-Vis 和 TEM 结果表明，在第 3 天之前，AuENPs 在孔隙水中既存在同聚体也存在异聚体，之后在孔隙水中的浓度太低而无法检测到聚集体的存在。孔隙水中 Au 和 Fe 的浓度之间存在密切关系，表明 Au 的短期溶解度部分受天然土壤胶体控制。结果表明，在正常充气土壤条件下，Ag 和 AuENPs 的实际有效性很低，这与风险评估有关，尽管需要进一步研究环境条件和土壤特性对保留在固体基质中的 ENPs（和/或大的 ENPs 聚集体）的反应性的影响。
