Dynamics of the Dissipation of Acetamiprid, Azoxystrobin, and β-Cyfluthrin in Jalapeño Pepper (Capsicum annuum L.) Produced Under Greenhouse and Open-Field Conditions

Pepper is one of the most widely consumed foods around the world. China is the leading producer, while Mexico is the primary exporter. To support these roles, the responsible use of agrochemicals is essential. Additionally, investigating the factors influencing pesticide dissipation is critical to ensure that residue levels do not exceed established Maximum Residue Limits (MRLs) and to achieve the required pre-harvest interval (PHI). This is essential to prevent trade-related issues and mitigate potential health risks to consumers. Consequently, this study aims to evaluate the dissipation dynamics of acetamiprid, azoxystrobin, and β-cyfluthrin residues in jalapeño peppers cultivated under both greenhouse and open-field conditions. Three applications of a manufacturer's suggested dosage were evaluated, with 7-day intervals between each. The residual content was quantified after 1 h and 1, 3, 7, 14, and 21 days following each application. A QuEChERS method utilizing ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) and gas chromatography equipped with a micro electron capture detector (GC-µECD) to determine the pesticide residues was optimized and validated, obtaining suitable performance, with satisfactory linearity, detection and quantification limits, recovery rates, and accuracy. The dissipation curves were constructed from the residues and dissipation percentages of the pesticides over time, elucidating the initial residuality, accumulation, half-life, residence time, and total persistence of the active ingredient. In addition, an analysis was carried out, relating climatic conditions to the cumulative dissipation of pesticides. The results show an increase in the initial residues, half-life, and residence time of pesticides in the greenhouse. Otherwise, in the open field, the residues of the pesticides acetamiprid and azoxystrobin increased over the initial applications. Climatic conditions, mainly evapotranspiration during crop growing, involve the dissipation of pesticides in jalapeño pepper. The validation method demonstrated satisfactory parameters, aligning with the guidelines provided by the US EPA and SENASICA. All concentrations quantified in real samples were found to be below the MRLs, ensuring compliance with regulatory standards. Additionally, the dissipation kinetics played a critical role in elucidating key aspects such as residence times, latency periods, and marketing timelines for ensuring food safety. This kinetics provided essential insights into the behavior and persistence of the residues, contributing to a more comprehensive understanding of their dynamics in agricultural and commercial contexts. We believe these findings underscore the reliability and applicability of the method for monitoring pesticide residues in real-world scenarios.