Removal of neurotoxic ethyl parathion pesticide by two-stage chemical/enzymatic treatment system using Fenton's reagent and organophosphorous hydrolase

Abstract

Organophosphate compounds, which are essential ingredients of pesticide, plasticizer, air fuel, and chemical warfare agents, are serious neurotoxic hazardous materials. Therefore, diverse physical-chemical treatments have been attempted to degrade organophosphate compounds. In the present work, we propose a two-stage chemical and enzymatic treatment system. As a first stage, pretreatment of oxidation and coagulation using Fenton's reagent utilizing iron and hydrogen peroxide was employed. Preferentially, 1 mM ethyl parathion (EP) pesticide was largely (similar to 80%) removed by Fenton's reagent reaction within 15 min. To remove residual EP, enzymatic treatment with organophosphorous hydrolase (OPH) from recombinant Escherichia coli was employed as a second stage. We successfully demonstrated that the proposed two-stage hybrid treatment process removed 1mM environmental toxic EP efficiently (similar to 98%) within 30 min.