A multiclass analytical method for pesticides determination in water using DLLME and GC-MS

Abstract

This work aimed to develop and validate a method for the determination of trifluralin, metribuzin, metolachlor, endosulfan, λ-cyhalothrin, permethrin and malathion in water using dispersive liquid-liquid microextraction (DLLME). The mixture n-hexane/toluene (60:40 v/v) showed high extraction capacity and was used in the method validation. The method was applied to different surface water samples and a matrix effect was not observed. The DLLME provided recovery of 47-115 % with a RSD up to 16%. The detection limits ranged between 0.0063 and 0.046 μg L-1 whereas the method quantitation limit was 2.0 μg L-1 for all analytes. After validated, the method was applied to water samples collected in an agricultural region of Mato Grosso State, Brazil and only permethrin was detected. The proposed method can be an alternative for the simultaneous determination of multiclass pesticides in water, with the advantage of being fast and using a very small amount of solvent.