Evaluation of electrolysed water as an agent for reducing methamidophos and dimethoate concentrations in vegetables

Abstract

Summary In a model system, mixing strong acidic electrolysed oxidising (AC) water with either methamidophos or dimethoate reduced the initial concentrations by more than 99%. Using NaOH solution (pH 11.24) or strong alkaline electrolysed (AK) water resulted in a 98% of methamidophos in 10 min. In contrast, the alkaline solutions only reduced dimethoate concentrations by 35–40%. In food systems, vegetables were soaked in tested pesticide solutions and air‐dried. They were then shaken or ultrasonicated in deionised water, AC water and/or AK water for specified time periods. AK water reduced methamidophos and dimethoate concentrations in leafy cabbage by 33.8% and 31.6%, respectively, and in green pepper by 17.0% and 28.7%, respectively. Continuously changing electrolysed water further decreased the methamidophos and dimethoate concentrations in leafy cabbage by 79.3% and 89.3%, respectively. Electrolysed water was more effective in leafy vegetables than in fruit vegetables because of the pH and the oxidation effect as well as the continuous changing of test solutions.