Mobility Study of TiO₂ Nanoparticles in Soil and Their Impact on Soil Nutrients

ABSTRACT

This mobility study aimed to determine the transport of TiO₂ NPs from topsoil to deeper zones. The saturated soil column method imitated TiO₂ NPs transport in real-world conditions and possible leaching scenarios. Three soils were studied: City soil (S_City), Agricultural (S_Agri), and Sand. This investigation used ICP-OES, EDX, SEM and DLS to determine TiO₂ NPs sizes, track the mobility patterns and quantify them in soil layers. The results have revealed that the mobility and retention of TiO₂ NPs were highly influenced by Clay, organic matter (OM), and CEC. The concentration of TiO₂ NPs in the deepest soil layers and the breakthrough water was low in S_City, in which Clay and OM were high. In contrast, TiO₂ NPs were relatively high in the lowest layers of S_Agri, where the Clay and OM content was insignificant. The columns packed with Sand showed the highest transported of TiO₂ NPs where Clay and OM were absent. The breakthrough water obtained from Sand columns showed the highest TiO₂ NPs concentration, followed by S_Agri and S_City. The columns packed with S_City had more TiO₂ NPs retention due to the presence of CEC in Clay and OM. This investigation showed that the transport of TiO₂ NPs in the soil at low concentrations is a fact. It depends on soil properties such as texture, OM content, pH, and CEC.

KEYWORDS:

• TiO₂ nanoparticles
• mobility
• soil column
• soil saturation

Acknowledgments

We express our gratitude to the Indian Council for Cultural and Relations (ICCR) for their financial assistance by awarding Djibril Sekou Keita a full scholarship for his doctoral research.

Disclosure statement

No potential conflict of interest was reported by the authors.