Multi-residue Determination Method Of Pesticides In Drinking Water By Solid-phase Extraction Followed By Gas Chromatography With Electron Capture Detector

Objective A multiresidue method based on solid-phase extraction andgas chromatography with electron capture detector was developed for thesimultaneous determination of 15 pesticides (Dichlorvos, Dimethoate,Parathion-methyl, Malathion, Parathion, Fenpropathrin, Lambda-cyhalothrin,Cypermethrin,Esfenvalerate,Deltamethfin,Quintozene,Dieldrin,Heptachlor,α-Endosulfan,β-Endosulfan) in drinking water.Method The extraction procedure was carried out in ENVI-C₁₈ columnspreconditioned with methanol and water. The subsequent elution of pesticideswas performed with a mixture of acetone- hexane (25:75, v/v) prior to thedetermination by gas chromatography with electron capture detector, therecoveries of pyrethroids were remarkably increased by rinsing the containercontaining the sample with 5mL elution.Result Average recoveries for all the pesticides studied were higher than70% and relative standard deviations were below 13 % in the concentrationrange of 0.05～1.0μg/mL for organophosphorous and pyrethroids, 0.01～0.2μg/mL for organochlorine, the method showed good linearity ranges for allpesticides with correlation coefficients greater than 0.996. the detection limitsachieved ranged from 0.0021～0.032μg/L. Conelusion This method was simple,rapid,sensitive,accurate and safefor determination multiresidue of pesticides in drinking water.