Abiotic soil changes induced by engineered nanomaterials: A critical review

Area of Science:

• Environmental Science
• Soil Science
• Materials Science

Background:

• Engineered nanomaterials (ENMs) are increasingly studied for their fate in soil-water systems, focusing on transport, persistence, and toxicity.
• While soil is recognized as a primary sink for ENMs, research on their impact on soil matrix properties remains limited.
• Chemical contaminants are known to alter soil properties through direct or indirect mechanisms, influencing biological activity.

Purpose of the Study:

• To review the deposition, retention, and accumulation of ENMs in soil.
• To examine how retained ENMs modify soil surface properties, including sorption capacity, surface charge, and composition.
• To demonstrate the resulting physical and hydrological changes in soil properties due to ENM accumulation.

Main Methods:

• Literature review of studies on ENM fate and behavior in soil.
• Analysis of research on ENM-induced changes in soil sorption, surface characteristics, and physical properties.
• Synthesis of findings to assess the overall impact of ENMs on soil structure and function.

Main Results:

• Soil acts as a significant sink for ENMs, with limited degradation or mobilization.
• Accumulated ENMs alter soil surface properties, affecting sorption of other solutes and changing surface charges.
• Significant modifications in soil physical and hydrological properties, such as hydraulic conductivity, swelling, and wettability, are observed.

Conclusions:

• Engineered nanomaterials significantly alter soil properties, impacting its physical and hydrological functions.
• The accumulation of ENMs in soil represents a critical environmental impact that requires further investigation.
• Understanding ENM-induced soil changes is crucial for assessing the broader ecological consequences of nanomaterial release.