Detoxification of Triazophos Pesticide Residues in Foxtail Millets (Setaria Italica) Using Mid-Infrared Rays

Abstract

Pesticide residues in agricultural products are currently inevitable and pose severe risks to human health and the environment. Present detoxification technologies for residues are less effective, not eco-friendly, reduce sensory attributes and nutrients of the agro products, and are uneconomical.  To overcome this challenge to a certain extent, we developed a 2-6 µm mid-infrared generating atomizer, the mid-infrared was tried in the detoxification of pesticide viz. Triazophos. MIRGA accommodates water-based imbalance ionic solution. MIRGA spraying was performed externally over packaged (polythene >50 microns) foxtail millet (Setaria italica) mixed with different concentrations (5 to 10,000 ppm - 13 batches) of the commonly used pesticide Triazophos. The foraging behavior of fire ants was used as an indicator to evaluate triazophos toxicity. The foraging property was more significant in MIRGA-irradiated millet samples containing 5, 10, 50, and 100 ppm needed with 1-3 sprayings, 500-1000 ppm needed 2-5 sprayings, 2000 ppm needed 3 sprayings, 3000 ppm needed 2-4 sprayings, and 6000 ppm needed 4 or 5 sprayings than in non-irradiated (control) samples. As a result, we demonstrated the efficacy of 2–6 µm mid-IR detoxification. The 2-6 µm mid-infrared radiation generated by MIRGA was able to pass through the packaging material and interacted with the interior of foxtail millet. It was noted that foxtail millets sprayed with MIRGA containing 5 to 3000 ppm and 6000 ppm triazophos were eagerly consumed by ants. However, samples with 4000-5000 ppm and 7000-10,000 ppm were refused by the ants, while the blank control samples were consumed. The process of detoxification was studied by a variety of instrumentations and analytical investigations. The appearance of small peaks in the chromatogram data indicated a change in the components of the sample, resulting in the creation of new molecules that attracted ants more effectively. Two specific compounds identified post-spraying were 9,12-octadecadienoic acid (Z, Z) and 1-nonadecene, which explains the increased attractiveness of ants. The mid-IR radiation emitted during spraying led to the breakdown of some carbohydrates, releasing simpler sugars that are sweeter and naturally appealing to ants. The sprayed sample showed a fivefold increase in oleic acid content compared to the control sample, which may account for the reduced preference by ants. Furthermore, spraying induced alterations in various components such as aliphatic protons, methyl groups, olefinic protons, and aromatic protons within the samples. The application of MIRGA on foxtail millet containing triazophos induced structural changes at the micron level, as evidenced by particle agglomeration and the disappearance of elongated structures. The MIRGA technology proves to be a safe, cost-efficient, and environmentally friendly method. This outcome also hints at the potential of MIRGA in detoxifying residues of other agricultural chemicals.