Extração sólido-líquido com purificação em baixa temperatura miniaturizada para determinação do nematicida fluopyram em batata e solo

Abstract

Potatoes are one of the most important vegetables in the world due to their high production and consumption. The crop is frequently attacked by fungi and nematodes that compromise production and generate significant losses. In 2019, fluopyram, a fungicide and nematicide, was approved for use in Brazil to control nematodes in potato crops. However, a study on monitoring pesticide residues in potato crops has not yet been reported in the literature. Thus, the objective of this study was to optimize and validate the solid-liquid extraction with miniaturized low-temperature purification of fluopyram in potatoes, study the dissipation of the compound in the soil, and assess the dietary risk using the final residue detected in potatoes. The fluopyram extraction method was optimized in terms of extractor phase and sorbent for d-SPE. After optimization, the method was validated in terms of selectivity, limit of quantification, linearity, matrix effect, accuracy and precision. The results indicated that the extraction reached the quantification limit of 2 µg kg-1, being selective, linear, accurate, precise, and with a matrix effect of 326 %. Fluopyram monitoring in these matrices revealed that after 80 days there was an 85 % reduction in the pesticide concentration in the soil, with a half-life of approximately 5 days, and the residual concentration of fluopyram in the potatoes ranged from 174.9 to 345.5 µg kg-1, which is higher than the maximum residue limit established by Brazilian legislation (100 µg kg-1). Despite this, the dietary risk analysis revealed that the consumption of these potatoes does not pose a risk to human health.