Development of an analytical method for determining epoxiconazole fungicide in common beans

Common beans (Phaseolus vulgaris L.) have been the most widely cultivated legume in the world and play an important role in the traditional diet of many nations. This legume has been targeted by various pests and pathogens, mainly fungi, requiring the use of fungicides, such as epoxiconazole. This pesticide belongs to the triazole class, which has been associated with reprotoxicity, neurotoxicity, immunotoxicity, and cancer in humans. Due to its high global consumption, research on epoxiconazole in this matrix is important, as there is still no extraction method for this pesticide from beans. Therefore, this study aimed to optimize and validate solid-liquid extraction with low-temperature purification (SLE-LTP) to determine epoxiconazole in beans using gas chromatography coupled with mass spectrometry (GC-MS). The extraction phase and sorbents were optimized in this study to remove interfering substances from the matrix extracts. Optimal extraction conditions were obtained using acetonitrile and ethyl acetate (6.5 : 1.5) (v/v) as the extraction phase, followed by dispersive solid-phase extraction (d-SPE) using 25 mg of silica per milliliter of extract. Under these conditions, the technique achieved an average recovery rate of 101.23% and an RSD of ± 11.38 with intermediate precision between 5.44 and 13.58%. The limits of detection (LOD) and quantification (LOQ) achieved in this study were 3 and 10 µg kg^-1, respectively. Using this optimized and validated extraction technique, no epoxiconazole residues were detected in 18 commercial bean samples analyzed. The Analytical Eco-Scale metric assessment revealed that it reached 84 points, meaning this method is classified as an excellent green analysis technique.