Reduction of dichlorvos and omethoate residues by O2 plasma treatment.

A practical, inexpensive, and green chemical process is greatly needed for degrading pesticides in food and environmental water. In this work, the impact of O(2) plasma treatment on reduction of dichlorvos (DDVP) and omethoate in maize was determined by gas chromatography (GC). The main plasma-induced degradation mechanisms were investigated through identification of intermediates or products during O(2) plasma treatment for DDVP and omethoate on solid surfaces by gas chromatography/mass spectrometry (GC/MS). The results clearly demonstrate that O(2) plasma treatment is significantly effective in the degradation of original DDVP and omethoate, and the degradation efficiency mainly depends upon related operating parameters and chemical structures of pesticides. Moreover, GC/MS analyses show that DDVP and omethoate molecules are degraded into less-toxic compounds, and the plasma degradation mechanisms for pesticides can be dominated by a free-radical reaction. It is concluded that O(2) plasma has the potential to reduce pesticide residues in agricultural products.