Effects of ultrasound combined with ozone on the degradation of organophosphorus pesticide residues on lettuce

Abstract

Methamidophos (MDP) and dichlorvos (DDVP) are organophosphorous pesticides which are commonly used for pest control in agriculture to obtain better yields.

Chemical, Technological, and Sensory Properties of Wheat Grains (Triticum aestivum L) as Affected by Gaseous Ozonation

“…[16] The main reasons for applying O 3 in wheat grain are for pest and insect control, [17] elimination of fungi, [18] degradation of mycotoxin, [19,20] and degradation of pesticide residues. [21,22] As O 3 does not leave any residues in the treated food, there is no need for an aeration step after treatment, and also due to the excellent results of ozonation, it has been considered a "green alternative" to improve wheat quality. [23] Depending on the conditions used, O 3 may lead to positive changes in the grain or in the flour quality, such as, increase of bread and cake volume, increase of strength, and clarity of the flours.…”

Effective pretreatment technologies for fresh foods aimed for use in central kitchen processing

“…The combination of ultrasound, ozone, and ClO 2 could prolong the shelf life of strawberry. Similarly, Fan et al, 38 who employed ultrasound in combination with ozone to clean lettuce, found that the residues of organophosphorus pesticides, including methamidophos and dichlorvos, on the lettuce surface treated by ultrasound and ozone were significantly less than those observed when employing either of the two technologies alone. In addition, the quality of lettuce treated by the combined processes was not significantly compromised.…”

Sonochemical degradation of pesticides in aqueous solution: investigation on the influence of operating parameters and degradation pathway – a systematic review

“…In other words, at start, the content of pesticide molecules are relatively high, the utilization of ultrasound could sufficiently played roles in degradation, the reaction is accelerated, as prolonging the degradation time, pesticide molecules are degraded gradually, leading to a slower reaction. 70 The typical range of required degradation times using the ultrasonic process would be anywhere between 5 min to 1 h. It is important to characterize the degradation process in terms of kinetics and then optimum treatment time using sonication can be selected.…”

“…Hence, the enhancement of the mass transfer and dissociation processes of ozone coupled with high-localized temperatures and pressures upon the collapsing of cavities increase the generation of highly reactive hydroxyl radicals which results in a higher reaction rate. 70 The ultrasound/ozonation mechanism is proposed and illustrated in Fig. 7.…”

“…The formation of the large bubbles decreases the bubble-liquid interfacial region considerably, with a consequent reduction in the O 3 transfer rate from the gas phase to the liquid phase. 70,91 Wang et al 72 reported that the degradation efficiency of acephate by combined ultrasonic/ozonation method was 27% greater than the degradation efficiency when individual ozonation method was used aer 60 min.…”