MULTIRESIDUE AND MULTICLASS DETERMINATION OF CURRENT-USE PESTICIDES (CUPs) IN WATER SAMPLES BY SPE AND UHPLC-MS/MS

Given the extensive use of pesticides in modern times, residues are frequently detected in water samples. Therefore, this study developed and validated a method utilizing solid-phase extraction (SPE) with a polymeric sorbent for sample preparation in combination with ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). The aim was to determine a variety of current-use pesticides (CUPs) in different types of water. The preconcentration step, employing the polymeric sorbent Oasis HLB (60 mg), combined with the high selectivity and sensitivity of the UHPLC-MS/MS analysis, enabled the multiclass determination of pesticide residues in water samples at very low concentrations. The proposed method underwent validation, demonstrating satisfactory linearity, precision, and accuracy. The accuracy results, determined through recovery assays at varying spike levels (0.04-0.4 µg L-1), ranged from 71 to 117%, with precision expressed as relative standard deviations consistently below 19%. The practical limits of detection and quantification for most compounds were 0.01 and 0.04 µg L-1, respectively. This method was effectively employed to analyze drinking water, artesian well water, dam water, and river water, leading to the detection of various pesticides at concentrations of up to 2.24 µg L-1.