Effect of cerium oxide nanoparticles on asparagus lettuce cultured in an agar medium

Abstract

The increasing chances of manufactured nanoparticles (NPs) being released into the environment highlight the importance of understanding their interactions with plants, which are the basis of ecosystems. In this study, the phytotoxicity of CeO₂ NPs on asparagus lettuce was assessed. Lettuce seeds were treated with CeO₂ NPs in a plant agar medium at a wide range of concentrations (0–2000 mg L⁻¹) for 5 days. At high concentrations (≥500 mg L⁻¹), CeO₂ NPs altered the activity of superoxide dismutase (SOD), induced lipid peroxidation and cell membrane damage, and inhibited the root growth. The results of X-ray absorption near edge fine structure (XANES) indicate that part of the CeO₂ NPs were transformed from Ce(IV) to Ce(III) in the roots. The released Ce³⁺ may account for the phytotoxicity of CeO₂ NPs.