Comparative Efficacy of Household and Bio-Based Washing Agents for Reducing Cypermethrin Residues on Tomatoes (Lycopersicon esculentum)

Abstract

Background: The extensive use of pesticides in intensive vegetable production poses serious food safety concerns, particularly in developing countries where postharvest handling practices are often inadequate. Cypermethrin is widely applied to tomatoes in Pakistan and may persist on produce surfaces at concentrations exceeding recommended safety limits, increasing potential health risks to consumers. Objective: This study aimed to compare the effectiveness of selected household washing agents and a natural bio-based washing agent in reducing cypermethrin residues on tomatoes (Lycopersicon esculentum). Methods: Tomatoes were artificially contaminated with a cypermethrin solution at a concentration of one milliliter per liter. The samples were washed for ten minutes using one percent and two percent solutions of sodium hydrogen carbonate, sodium carbonate, sodium chloride, acetic acid, citric acid, and an alfalfa seed extract rich in saponins. Residual cypermethrin levels were determined using spectrophotometric analysis following solvent extraction. Main Outcome: The primary outcome measure was the percentage reduction of cypermethrin residues on tomato surfaces after washing. Results: Alkaline washing solutions demonstrated the highest residue reduction efficiency. Sodium carbonate achieved the greatest removal, with a maximum reduction of seventy-six point thirty-one percent at the two percent concentration. Sodium hydrogen carbonate and sodium chloride showed moderate effectiveness. Acidic solutions resulted in comparatively lower residue removal, while the alfalfa seed extract exhibited minimal reduction. Conclusion: Alkaline household washing agents, particularly sodium carbonate, are highly effective in reducing cypermethrin residues on tomatoes. These findings support the use of simple, accessible washing practices as practical strategies to improve consumer food safety at the household level.