Minimization of Imidacloprid Residues in Cucumber and Bell Pepper Through Washing with Citric Acid and Acetic Acid Solutions and Their Dietary Intake Assessment

Abstract

In order to assess the extent and fate of imidacloprid residues, the present research project was designed. Vegetables (cucumber and bell pepper) were collected from a supervised farmer's field. Fresh vegetables were dipped in organic acid solutions such as acetic acid (1.5, 3.0, 6.0, and 9.0%), citric acid (1.5, 3.0, 6.0, and 9.0%), and their combination (50:50 each) for 5 min. Imidacloprid residue level was determined before and after dipping in organic acids through high-performance liquid chromatography. The pesticide residue level was in the range of 0.12 ± 0.04 to 1.92 ± 0.04 mg/kg and 0.52 ± 0.02 to 1.89 ± 0.06 mg/kg in cucumber and bell pepper, respectively. The highest reduction of imidacloprid residue level was found after washing with 9% citric acid solution (93.75%) followed by a mixture of citric acid and acetic acid (1.5% each) solution (91.14%), and the lowest value was found in the mixture of citric acid and acetic acid (0.75% each) solution (48.43%) in cucumber. Likewise, in bell pepper, maximum decrease in imidacloprid content was revealed with 9% citric acid (72.48%), followed by 9% acetic acid (68.78%), and the least was observed with the mixture of citric acid and acetic acid (0.75% each) solution (11.64%). Dietary intake assessment of the pesticide residue was estimated according to the maximum permissible intake of imidacloprid, which is 3.78 mg/person/day. Dipping significantly reduced the amount of maximum permissible intake and ranged from (1.01 to 8.40 and 10.34 to 33.23 mg/kg of body weight/day) in cucumber and bell pepper, respectively. Organic acids dipping significantly reduced the imidacloprid content up to 80% in cucumber and bell pepper.