Reduction of Dichlorvos and Omethoate Residues by O₂ Plasma Treatment

Abstract

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.

Kinetics and mechanism for omethoate degradation by catalytic ozonation with Fe(III)-loaded activated carbon in water

“…Compound 3 (C3) with retention time 16.8 min could correspond to N-methyl-2-sulfanylacetamide through comparing its mass spectrum with that reported in a previous study (Bai et al, 2009). C3 had a molecular ion at m/z 105, which lose HSA to yield m/z 72 or lose HSCH 3 A to yield m/z 58.…”

“…The fragment ions at m/z 141 and 125 could originate from the loss of CH 3 A and CH 3 OA from the molecular ion, respectively. It has been reported that photo-and thermal-degradation of dimethoate would produce STMP (Andreozzi et al, 1999;Bai et al, 2009).…”

Atmospheric cold plasma dissipation efficiency of agrochemicals on blueberries

“…Recently, an inductively coupled plasma (ICP) source was employed for the degradation of dichlorvos and omethoate sprayed onto maize (Bai, Chen, Mu, Zhang, & Li, 2009;Bai, Chen, Yang, Guo, & Zhang, 2010). Heo et al (2014) investigated the efficacy of a dielectric barrier discharge (DBD) plasma for the degradation of pesticides on apples.…”

In-package nonthermal plasma degradation of pesticides on fresh produce

“…Unlike microbiological decontamination, only a limited number of studies have demonstrated the successful degradation of pesticides by NTP. The degradation of Dichlorvos and Omethoate organophosphorus pesticides sprayed onto maize samples when treated with an inductively coupled radiofrequency NTP source operating in oxygen was studied by Bai, Chen, Mu, Zhang and Li [8]. Recently, Bai, Chen, Yang, Guo and Zhang [9] also demonstrated the successful degradation of dichlorvos pesticides coated on glass slides using the same inductively coupled plasma (ICP) source.…”