Treatment of omethoate on edible wolfberry by atmospheric pressure air surface dielectric barrier discharge

In this study, the effect of atmospheric-pressure air surface dielectric barrier discharge (SDBD) on the degradation of Omethoate smeared edible wolfberry was investigated by gas chromatography and mass spectrometry (GC-MS). The degradation efficiency of SDBD on Omethoate is shown to be strongly dependent on the discharge voltage and plasma treatment time. The plasma-induced degradation mechanisms were studied through identification of the intermediates or by-products generated during SDBD plasma treatment. The results show that the degradation efficiency may be higher than 99% under the optimum discharge conditions, i.e., at the applied voltage of 10 kV and the treatment time of 30 min. It is concluded that the atmospheric-pressure SDBD plasma may degrade pesticide residue into nontoxic species (such as PO₄^3-, H₂O, SO₄^2-, and CO₂) during the plasma treating process. In this study, atmospheric-pressure air surface dielectric barrier discharge (SDBD) plasma is generated by self-made device, and it is used to degrade Omethoate smeared in edible wolfberry. Decomposition products are investigated and analyzed by gas chromatography and mass spectrometry (GC-MS). High-energy electrons and reactive species provided by SDBD plasma will decompose Omethoate into less toxic molecules. Other oxidation substances may lead less toxic molecules into nontoxic species (such as PO₄^3-, H₂O, SO₄^2-, NO_3-, and CO₂).