Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot, 7610001, Israel.
Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot, 7610001, Israel.
Chemosphere. 2021 Jan;262:127854. doi: 10.1016/j.chemosphere.2020.127854. Epub 2020 Aug 6.
Plastic nanoparticles (PNPs) are considered contaminants of emerging concern, but little information is available on their transport behavior in the soil-water environment, as well as their behavior relative to metal and other carbon-based nanoparticles. Here we show that size and surface functional groups affect the transport of polystyrene nanoparticles (PS-NPs) through saturated soil. Unmodified 110 nm and 50 nm PS-NPs demonstrated similar transport patterns in soil. However, a maximum elution value of 90% from the soil was found for the 50 nm PS-NPs, compared to a maximum value of ∼45% for 110 nm PS-NPs. The breakthrough curve for 190 nm PS-NPs demonstrated a maximum elution value of 60% from the soil. PS-NPs with surface functional groups display different mobility profiles: carboxylated PS-NPs demonstrated a plateau of 40% elution from the soil, while aminated PS-NPs were eluted only in small amounts and showed a spike pattern of elution from the column. These findings are attributed to the effects of common soil constituents such as calcium cations and humic acids on the size and charge of the PS-NPs with surface functional groups. Overall, PS-NP mobility in soil can vary widely, depending on PNP properties such as size and surface chemistry, and on matrix properties, such as the type of porous medium and its composition. These findings suggest that knowledge of inherent characteristics (size, surface charge, surface functional groups) of PNPs are required to elucidate the behavior of such particles in soil-water environments, and predict the extent of contaminant spreading.
塑料纳米颗粒（PNPs）被认为是新兴关注的污染物，但关于它们在水土环境中的迁移行为，以及它们与金属和其他基于碳的纳米颗粒的行为关系的信息很少。在这里，我们表明，尺寸和表面官能团会影响聚苯乙烯纳米颗粒（PS-NPs）在饱和土壤中的传输。未经修饰的 110nm 和 50nm PS-NPs 在土壤中的传输模式相似。然而，50nm PS-NPs 的最大洗脱值为 90%，而 110nm PS-NPs 的最大洗脱值约为 45%。190nm PS-NPs 的穿透曲线显示，从土壤中最大洗脱值为 60%。带有表面官能团的 PS-NPs 表现出不同的迁移分布：羧基化 PS-NPs 显示出 40%的洗脱平台，而氨基化 PS-NPs 仅少量洗脱，并显示出从柱中洗脱的尖峰模式。这些发现归因于常见土壤成分（如钙离子和腐殖酸）对具有表面官能团的 PS-NPs 的尺寸和电荷的影响。总的来说，PS-NP 在土壤中的迁移性差异很大，这取决于 PNP 的特性，如尺寸和表面化学性质，以及基质特性，如多孔介质的类型及其组成。这些发现表明，需要了解 PNPs 的固有特性（尺寸、表面电荷、表面官能团），以阐明这些颗粒在水土环境中的行为，并预测污染物扩散的程度。
