Oxidative technologies for olive grove soils: Impacts of electrogenerated H2O2 and O3 on pesticide degradation and ecosystem health

This work investigates the application of electrochemically generated green oxidants for in situ soil remediation, focusing on hydrogen peroxide (H 2 O 2 ) and ozone (O 3 ) produced on demand. Real olive grove soils contaminated with atrazine and glyphosate were treated under bench-scale conditions for up to 30 days. Removal efficiency was evaluated as a function of oxidant delivery and oxidant-to-contaminant ratio, together with an assessment of potential impacts on soil biological activity. Both oxidants promoted effective pesticide degradation, with atrazine removals exceeding 60% for H 2 O 2 and 40% for O 3 , while glyphosate degradation reached up to 25% and 21%, respectively. Results indicate that contaminant removal was primarily limited by oxidant transport rather than oxidant concentration. Biological analyses revealed a marked suppression of soil respiration and increased nematode mortality following H 2 O 2 treatment, whereas O 3 caused minimal disturbance to soil biological functioning. These findings demonstrate that electrochemically generated ozone is a promising, field-compatible remediation strategy, providing effective contaminant removal while preserving soil ecosystem functionality. • On-demand electrochemical H 2 O 2 and O 3 for in situ olive soil remediation. • Atrazine degradation >60% with H 2 O 2 and 40% with electro-generated O 3 . • Oxidant transport, not concentration, controls removal efficiency in olive soils. • Aqueous H 2 O 2 reduced soil respiration and increased nematode mortality. • Electro-generated O 3 removed contaminants with minimal impact on soil biota.