Determination of cereal herbicide residues in envi

ELSEVIERJournalofChromatographyA,754(1996)347-365JOURNALOFCHROMATOGRAPHYAReviewsDeterminationofcerealherbicideresiduesinenvironmentalsamplesbygaschromatographyJ.L.Tadeo*,C.Sanchez-Brunete,A.I.Garcfa-Valcarcel,L.Martfnez,R.A.P6rezAreadeProteccidnVegetal,CIT-INIA,Apdo8111,28080Madrid,SpainAbstractGaschromatographicanalysisofcerealherbicideresiduesinwater,soil,plantandairisreviewed.Herbicideswidelyusedinspringandwintercereals,i.e.,phenoxyacids,benzonitriles,ureas,triazines,dinitroanilines,chloroacetamidesandthiocarbamates,areconsidered.Themainproceduresusedintheresidueanalysis,extraction,clean-up,derivatizationandgaschromatographicdeterminationaresummarizedanddiscussed.Keywords:Reviews;Environmentalanalysis;Samplepreparation;Derivatization,GC;PesticidesContentsI.Introduction............................................................................................................................................................................3472.Extractionandclean-up...........................................................................................................................................................3492.1.Phenoxyacidsandbenzonitriles.........................................................................................................................................3492.2.Ureas..............................................................................................................................................................................3512.3.Triazines.........................................................................................................................................................................3522.4.Dinitroanilines.................................................................................................................................................................3532.5.Chloroacetamides.............................................................................................................................................................3532.6.Thiocarbamates................................................................................................................................................................3552.7.Multiresidue....................................................................................................................................................................3553.Derivatization.........................................................................................................................................................................3594.GCdetermination....................................................................................................................................................................36(}4.1.Columns..........................................................................................................................................................................3604.2.Detectors.........................................................................................................................................................................3605.Conclusions............................................................................................................................................................................361References..................................................................................................................................................................................361I.IntroductionCerealsareoneofthemostimportantcropscultivatedallovertheworldsincethebeginningof*Correspondingauthor.agriculture.Inthesecrops,herbicidesarewidelyusedatpresent,particularlyinthemoredevelopedcountries.Thiswidespreadusecontributestotheirpresenceintheenvironmentandthusherbicidesareoftenfoundinsurfaceandgroundwater[1]andinotherenvironmentalmatrices[2].0021-9673/96/$15.00©1996ElsevierScienceB.V.AllrightsreservedPIIS0021-9673(96)00279-8348J.L.Tadeoetal.IJ.Chromatogr.A754(1996)347-365Theherbicidesreviewedinthispaperaresumma-rizedinTable1andtheirmolecularstructureshowninFig.1.Thecropwheretheyarenormallyappliedandsomeimportantphysical-chemicalpropertiesoftheseherbicidesarealsopresentedinTable2[3].Residueanalysisofthesecompoundswasinitiallycarriedoutbycolorimetricmethods[4,5]orbythin-layerchromatography[6,7].Atpresent,gaschromatography(GC)isthetechniquemorecom-monlyusedintheresidueanalysisoftheseher-bicidesinenvironmentalsamples,duetothehighsensitivityobtainedwithnitrogen-phosphorous(NPD)andelectron-capture(ECD)detectionandtotheselectivityandidentificationofresiduesachievedbycouplingGCwithmassspectrometry(MS).Analternativetechniquewithgrowinguseinthede-terminationofpesticideresidues,particularlyinwatersamples,ishigh-performanceliquidchroma-tography(HPLC)[8,9].Variousreviewshavebeenpublishedonpesticideresidueanalysis[9-12].Inthisreviewwewillfocusonresidueanalysisofcerealherbicidesinenviron-mentalsamples,water,soil,plantandair,bygaschromatography