Determination of the residues of 18 carbamate pesticides in chestnut and pine nut by GPC cleanup and UPLC-MS-MS.

A new method using gel permeation chromatography (GPC) cleanup followed by ultra-performance liquid chromatography combined with tandem mass spectrometry (UPLC-MS-MS) has been established for simultaneous determination of 18 carbamate pesticides in nuts (chestnut and pine nut). Recoveries obtained by fortifying nut (spiking at 0.02 mg/kg) range from 70.21% to 89.56%. The proposed method features good sensitivity. Its limits of quantification are low enough to allow pesticide residues to be determined at concentrations below the maximum residue levels legally accepted. The precision, expressed as relative standard deviation, ranges from 2.26% to 4.07%.