An analytical method, using ion chromatography coupled to high resolution mass spectrometry was developed and validated to quantify glyphosate, glufosinate, ethephon, fosetyl aluminium and their related metabolites. This method allows multiresidue analysis of 11 highly polar molecules in a single chromatographic run, without derivatization step, using acidified water with low level of acetonitrile as extraction solvent. Three different matrices that are representative of commodity group were studied and validated: one fruit (grapes), one cereal (wheat) and honey, according to the criteria established by SANTE/12682/2019 taking into account maximum residue limits indicated by Regulation (EC) No. 396/2005, confirming that the procedure was selective, repeatable and robust. Matrix effect was studied and linearity was evaluated comparing analytical response differences between solvent standard solutions and matrix-matched calibration curve. Due to the relevant matrix effect observed, the use of response factor (RF) approach to quantify analytical batch was evaluated, using isotopically labelled internal standardisation. The in-depth study, validation results and several proficiency tests, used to verify procedure performance, demonstrated that the method is fit for purpose to routine analysis in an official laboratory. Moreover, it allows surveillance activities in fruits and vegetables control, as indicated by European Community, furthermore monitoring presence of polar pesticides, at low level, in some particular food as honey that could become environmental pollution indicator. K E Y W O R D S glyphosate, high resolution mass spectrometry, ion chromatography, method validation, polar pesticides 1 | INTRODUCTION Glyphosate and other similar pesticides are used in agriculture to combat weeds that compete with crops. They are generally applied before sowing and as a preharvest drying treatment to optimize the ripening process. The discovery of the glyphosate molecule dates back to 1950, but its usefulness in the agriculture field was not immediately identified; only in 1970, a Monsanto chemist studied the herbicide activity and its applications. 1 The use of this molecule, in different formulation, from its discovery to today, has increased exponentially; however, resistance mechanisms have been developed by the
