Green photosensitisers for the degradation of selected pesticides of high risk in most susceptible food: A safer approach

Abstract

Pesticides are the leading defence against pests, but their unsafe use reciprocates the pesticide residues in highly susceptible food and is becoming a serious risk for human health. In this study, mint extract and riboflavin were tested as photosensitisers in combination with light irradiation of different frequencies, employed for various time intervals to improve the photo-degradation of deltamethrin (DM) and lambda cyhalothrin (λ-CHT) in cauliflower. Different source of light was studied, either in ultraviolet range (UV-C, 254 nm or UV-A, 320–380 nm) or sunlight simulator (> 380–800 nm). The degradation of the pesticides varied depending on the type of photosensitiser and light source. Photo-degradation of the DM and λ-CHT was enhanced by applying the mint extracts and riboflavin and a more significant degradation was achieved with UV-C than with either UV-A or sunlight, reaching a maximum decrement of the concentration by 67–76%. The light treatments did not significantly affect the in-vitro antioxidant activity of the natural antioxidants in cauliflower. A calculated dietary risk assessment revealed that obvious dietary health hazards of DM and λ-CHT pesticides when sprayed on cauliflower for pest control. The use of green chemical photosensitisers (mint extract and riboflavin) in combination with UV light irradiation represents a novel, sustainable, and safe approach to pesticide reduction in produce.

A review on pesticides degradation by using ultraviolet light treatment in agricultural commodities

“…It is essential to recognize that most studies on pesticide residue degradation have been conducted on a small scale, such as in laboratory or pilot studies. UV treatment for pesticide degradation can impact the nutrient content of the foods depending on numerous factors such as exposure duration, light source, food type, specific pesticide involved and other relevant factors (Baig et al, 2021; Li & Bradley, 1969; Tabasum et al, 2020). For example, Li and Bradley (1969) studied the effectiveness of UV light exposure in removing organochlorine pesticides from the butter oil and milk.…”

“…Baig et al (2021) studied the mint extract and riboflavin as photosensitisers in conjunction with different wavelengths of light over varied intervals to actively promote the photodegradation of deltamethrin (DM) lambda‐cyhalothrin (λ‐CHT) in cauliflower. UV light spectrum (UV‐C, 254 nm or UV‐A, 320–380 nm) and solar simulator (>380–800 nm) investigated the degradation of insecticides.…”

“…Another study, in the presence of mint and riboflavin extracts as photosensitizers, UV‐C light proved to be more effective in degradation of DM and λ‐CHT compounds in cauliflower compared to UV‐A or sunlight, resulting in concentration reductions of 67%–76%. Notably, the nutrients and natural antioxidants present in cauliflower remained unaffected during the light treatments (Baig et al, 2021). Similarly, the quality parameters such as color, acidity and peroxide index had no significant difference after UV exposure for degradation of 24 different pesticides in Virgin olive oil (Nieto et al, 2009).…”