Dror Ishai, Yaron Bruno, Berkowitz Brian
Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot 76100, Israel.
Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot 76100, Israel.
J Contam Hydrol. 2015 Oct;181:3-16. doi: 10.1016/j.jconhyd.2015.04.004. Epub 2015 Apr 17.
A large number of research papers on the fate of engineered nanomaterials (ENMs) in the soil-water system have appeared in recent years, focusing on ENM transport, persistence and toxicological impact. It is clear from these publications that soil is a major sink for ENMs, and that only a small portion degrades or is mobilized further into groundwater. However, to date, very few studies have examined the impact of ENMs on the natural soil-subsurface matrix and its properties. Moreover, it is now well accepted that chemical contaminants are capable of changing soil properties either by inducing direct chemical or physical changes, or through indirect changes by, e.g., influencing biological activity that in turn modifies soil properties. Here, we review studies on the deposition, retention, and accumulation of ENMs in soil, indicative of the extent to which soil acts as a major sink of ENMs. We then examine evidence of how these retained particles lead to modification of surface properties, which are manifested by changes in the sorption capacity of soil for other (organic and inorganic) solutes, and by surface charges and composition different than the natural surfaces. Finally, we demonstrate how this results in physical and hydrological changes to soil properties, including hydraulic conductivity, swelling capacity and wettability. The overall picture revealed in this critical review sheds light on a perspective that has received little attention thus far. These aspects of soil change, due to exposure and subsequent accumulation of ENMs, may ultimately prove to be one of the most important impacts of ENM releases to the environment.
近年来，出现了大量关于工程纳米材料（ENM）在土壤 - 水系统中归宿的研究论文，重点关注ENM的迁移、持久性和毒理学影响。从这些出版物中可以清楚地看出，土壤是ENM的主要汇，只有一小部分会降解或进一步迁移到地下水中。然而，迄今为止，很少有研究考察ENM对天然土壤 - 地下基质及其性质的影响。此外，现在人们已经普遍接受化学污染物能够通过引起直接的化学或物理变化，或通过间接变化（例如，影响生物活性进而改变土壤性质）来改变土壤性质。在此，我们综述了关于ENM在土壤中的沉积、滞留和积累的研究，这些研究表明了土壤作为ENM主要汇的程度。然后，我们考察了这些滞留颗粒如何导致表面性质改变的证据，这些改变表现为土壤对其他（有机和无机）溶质吸附能力的变化，以及表面电荷和组成与天然表面不同。最后，我们展示了这如何导致土壤性质在物理和水文方面的变化，包括水力传导率、膨胀能力和润湿性。这篇批判性综述揭示的总体情况为一个迄今为止很少受到关注的观点提供了启示。由于ENM的暴露和随后的积累而导致的土壤这些变化方面，最终可能被证明是ENM释放到环境中最重要的影响之一。
