Validation and application of quick polar pesticide (QuPPe) extraction and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) to analyze perchlorate in vegetables from Mexico

Perchlorate is a contaminant and endocrine disruptor present in vegetables. To address the lack of information on this problem in Mexico, we developed an analytical method to quantify perchlorate in commonly consumed vegetables based on quick polar pesticide (QuPPe) extraction and ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS). The method was validated through the parameters of selectivity, accuracy, precision, linearity, limit of detection (LOD), and limit of quantification (LOQ) according to SANTE guidelines. The developed method exhibited a linear range of 0.005–0.100 mg/kg with LOD and LOQ values of 0.001 and 0.003 mg/kg, respectively. Recovery in a fortified tomato matrix was 96.85 ± 12.90% with a coefficient of variation (CV) of 11.55 ± 0.84%. The method was applied to analyze 31 vegetable samples collected from different regions in Mexico. Perchlorate concentrations ranged from not detected (ND) to 0.016 mg/kg, fresh weight. This method generates robust scientific evidence to implement and strengthen perchlorate monitoring programs for food matrices, supporting efforts to regulate this analyte in Mexico.