Organophosphate insecticide degradation by non-amended and cupric ion-amended Fenton's reagent in aqueous solution.

Improper treatment and disposal of pesticide-contaminated wastewaters raise concerns for soil and water contamination. Based on the pilot studies described here, chemical treatment via Fenton's reagent (ferrous ion plus hydrogen peroxide) of three organophosphorus insecticides in aqueous solution appears promising. Results show that the Fenton dark reaction degrades methyl parathion, malathion, and methamidophos, and in many cases their breakdown products as well. Addition of cupric ion greatly accelerates insecticide disappearance. To maximize degradation, further studies of the influence of 1) pesticide structure, 2) reagent ratios, and 3) breakdown product competition on reaction rates are necessary.