Liquid-phasemicroextraction–gaschromatography–massspectJournalofChromatographyA,1148(2021)145–151Liquid-phasemicroextraction–gaschromatography–massspectrometryforthedeterminationofbromate,iodate,bromideandiodideinhigh-chloridematrixKishanReddy-Noone,ArchanaJain,KrishnaK.VermaDepartmentofChemistry,RaniDurgavatiUniversity,Jabalpur482021,MadhyaPradesh,IndiaReceived24December2021;receivedinrevisedform5March2021;accepted7March2021Availableonline16March2021AbstractInthedeterminationofbromateandiodate,anyfreebromideandiodidepresentwasquantitativelyremovedbyanionexchangewithsilverchlorideexploitingthedifferencesinsilversaltssolubilityproduct,beingAgCl,1.81010,AgBr,5.01013,AgI,8.31017,AgBrO3,5.5105andAgIO3,3.1108.Theoxyhalideswerereducedwithascorbicacidtohalidesandconvertedto4-bromo-2,6-dimethylanilineand4-iodo-2,6-dimethylanilinebytheirreactionwith2-iodosobenzoateinthepresenceof2,6-dimethylanilineatpH6.4and2–3,respectively.Singledropmicroextraction(SDME)ofthehaloanilinesin2loftolueneandinjectionofthewholeextractintoGC–MS,orliquid-phasemicroextraction(LPME)into50loftolueneandinjectionof2lofextract,resultedinasensitivemethodforbromateandiodate.Thelattermethodofextractionhasbeenfoundmorerobust,sensitiveandtogivebetterextractioninshorterperiodthanSDME.Totalbromine/iodinewasdeterminedwithoutanytreatmentwithsilverchloride.Highconcentrationofchlorideinthematrixdidnotinterfere.Arectilinearcalibrationgraphwasobtainedfor0.05g–25mgl1ofbromate/bromideandiodate/iodide,thelimitofdetectionwere20ngl1ofbromate,15ngl1ofiodate,20ngl1ofbromideand10ngl1ofiodide(byLPMEin50loftoluene).Themethodhasbeenappliedtoseawaterandtablesalt.Fromthepooleddata,theaveragerecoveryofspikedoxyhalide/halidetorealsampleswasinrange96.7–105.7%withRSDinrange1.6–6.5%.2021PublishedbyElsevierB.V.Keywords:Bromate;Iodate;Iodide;Bromide;High-chloridematrix;Liquid-phasemicroextraction;Singledropmicroextraction;Gaschromatography–massspectrometry1.IntroductionOntheoccurrenceofhighamountsinenvironmentalsamples,bromiderepresentsahazardtopublichealth[1,2].Long-termelevateddietarylevelsofbromideexertchangesonthestatusofthethyroidgland,witheventualsubstitutionofiodidebybro-mideduringbiosynthesisofthyroidhormones[3,4].Brominatedandiodinatedcompoundsareproducedduringthedisinfectionofwaterbychlorineinthepresenceofbromideandiodide[5,6].Toxicologicalstudiessuggestthatbrominatedandiod-inatedcompoundsmaybemorecarcinogenicthanchlorinatedanalogues[7].Ozone,usedasanalternativedisinfectanttochlo-rine,generatesbromateasaby-productinwaterscontainingtheCorrespondingauthor.Tel.:+917612678103;fax:+917612403252.E-mailaddress:arichna@sancharnet.in(K.K.Verma).precursorbromide.Bromatehasbeenclassiedasagroup2Bprobablehumancarcinogen[8].In1993,theWHOsetalimitof25gl1forbromateindrinkingwater[9].Despitethehealthrisks,thisguidelinewasbasedonthelimitationsofthemeasure-menttechniquesforbromate.TheUSEnvironmentalProtectionAgency(EPA)setamaximumcontaminantlevelof10gl1bromateunderStage1Disinfectants/DisinfectionByproductsRulein1998[10].TheEUreducedtheirregulatoryvaluefrom50to10gl1bromateindrinkingwater[11]andtheWHOalsosetaguidelineof10gl1[12].Acancerriskof1in105hasbeenassessedat0.5gl1bromatebasedoningestionofdrinkingwater[13].Ionchromatographyhasbeentraditionallyusedfordeter-miningbromate,otheroxyhalidesandhalidesusingacarbonateeluentandsuppressedconduct...