关乎全球命运的持久性有机污染物POPS：当前和今后的研究方向

ReviewGlobalfateofPOPs:CurrentandfutureresearchdirectionsRainerLohmanna,*,KnutBreivikb,c,JordiDachsd,DerekMuireaGraduateSchoolofOceanography,UniversityofRhodeIsland,Narragansett,RI02882-1197,USAbNorwegianInstituteforAirResearch,POBox100,NO-2027Kjeller,NorwaycUniversityofOslo,DepartmentofChemistry,POBox1033,NO-0315Oslo,NorwaydDepartmentofEnvironmentalChemistry,InstituteofChemicalandEnvironmentalResearch(IIQAB-CSIC),JordiGirona18e26,Barcelona08034,SpaineAquaticEcosystemProtectionResearchDivision,EnvironmentCanada,867LakeshoreRoad,Burlington,ONL7R4A6,CanadaReceived30March2007;receivedinrevisedform5June2007;accepted8June2007FuturestudiesintotheglobalfateofPOPswillneedtopaymoreattentiontothevariousbiogeochemicalandanthropogeniccyclestobetterunderstandemissions,transportandsinks.AbstractForlegacyandemergingpersistentorganicpollutants(POPs),surprisinglylittleisstillknowninquantitativetermsabouttheirglobalsourcesandemissions.AtmospherictransporthasbeenidentifiedasthekeyglobaldispersalmechanismformostlegacyPOPs.Incontrast,transportbyoceancurrentsmayprovetobethemaintransportrouteformanypolar,emergingPOPs.ThisislinkedtothePOPs’intrinsicphysico-chemicalproperties,asexemplifiedbythedifferentfateofhexachlorocyclohexanesintheArctic.Similarly,ourcurrentunderstandingofPOPs’globaltransportandfateremainssketchy.TheimportanceoforganiccarbonandglobaltemperaturedifferenceshavebeenacceptedaskeydriversofPOPs’globaldistribution.However,futureresearchwillneedtounderstandthevariousbiogeochemicalandgeophysicalcyclesunderanthro-pogenicpressurestobeabletounderstandandpredicttheglobalfateofPOPsaccurately.2007ElsevierLtd.Allrightsreserved.Keywords:Persistentorganicpollutant;POP;Sources;Fate;trends1.IntroductionPersistentorganicpollutants(POPs)constituteadiversegroupoforganicsubstances,whicharetoxic,persistent,bio-accumulativeandpronetolong-rangetransport.Theyhavedifferentintrinsicphysical-chemicalproperties,whichdictatetheirenvironmentalbehavior(seeWania,2003,2006;Fig.1).Equallyimportant,theirsourcesandpathwaysforre-leaseintotheglobalenvironmentvaryaswell.POPscanbeclassifiedasflyers,multi-,singlehoppersandswimmers(Fig.1).ThisassignmentwasbasedonthemajormodesofchemicaltransportbehavioronaglobalscaleaccordingtotheirspecificpartitioningpropertycombinationsbyWania(2003).TheassessmentwasbasedontheresultsofArcticContaminationPotential(ACP)foremissionstoairovera10-yearperiodusingcalculationsforperfectlypersistentchemicals(Wania,2003).MostclassicalPOPs(e.g.,poly-chlorinatedbiphenyls(PCBs),DDT,chlorobenzenesandor-ganochlorinepesticides(OCPs)suchaschlordaneandtoxaphene)canbeclassifiedasmulti-hoppers(Wania,2003,2006)(seeFig.1A).Incontrasttothesemulti-mediachemi-cals,thehexachlorocyclohexanes(HCHs)areinthe‘‘swim-mers’’category.Fig.1BshowstheapproximatepositionsofarangeofchemicalsincommercebasedontheirpredictedormeasuredlogKAWandlogKOA.TheUNEPStockholmConvention(UNEP,2001)currentlyregulatestheso-called‘‘dirtydozen’’or‘legacy’POPs(seeTable1).Additionalsubstancesandsubstancegroupsare*Correspondingauthor:Tel.:þ14018746612;fax:þ14018746811.E-mailaddress:[e-mail](R.Lohmann).0269-7491/$-seefrontmatter2007ElsevierLtd.Allrightsreserved.doi:10.1016/j.envpol.2007.06.051EnvironmentalPollution150(2007)150e165(UNECE,1998)(seelowerpartofTable1).Itisconvenienttodiscriminatebetweenchemicalsthatarein-tentionallyproducedandchemicalsthatareformedasacci-dentalby-productsofvariouscombustionprocesses.Intheformergroup,thereisawiderangeofOCPsandsomeindus-trialchemicals,whilstthelattergroupcapturessubstanceslikepolychlorinateddibenzo-p-dioxinsanddibenzofurans(PCDD/Fs)andpolycyclicaromatichydrocarbons(PAHs).PAHsareonlyrecognizedasPOPsundertheAarhusProtocol(UNECE,1998).However,recentstudieshavehighlightedthatmanyin-dustriallyproducedcompoundsarealsoemittedduringcombustionprocesses.ThiswilllikelyreflectacombinationofdenovoformationofPOPssuchasPCBs,PCNaphthalenes,hexachlorobenzene(HCB)(e.g.,Bailey,2001;Leeetal.,2005)andthevolatilizationofintentionallyproducedcom-poundssuchaspolybrominateddiphenylethers(PBDEs)(Far-raretal.,2004).Bothinternationalagreementsmentionedearlierincludemechanismsforaddingnewsubstancesandsubstancegroupsifcertainspecifiedcriteriaaremet(UNECE,1998;UNEP,2001).Several‘‘new’’chemicalsofemergingenvironmentalconcernarecurrentlybeingscrutinizedforpossiblePOP-likebehavior.ThesepotentiallynewPOPs(‘‘emerging’’POPs)332104-567589101211-1-2-3-4logKOW=8“Classic”ArcticPOPsPBDE/HxBCDCyclicsiloxanesC10-C1chlorinatedparaffinsHaloalkylphosphatesTriarylphosphatesPolyfluoroalcoholsChlorinatedparaffins3210-1-2-3-4-5PerfluoroacidsPFOS,PFCAsHaloalkylphosphatesBromo-benzenes/cyclohexanesCyclicsiloxanesNEtFOSENMeFOSENEtFOSAPolyfluoroalcohols8:2FTOHBr-benz/cyclohexlogKOW=3logKOAlogKAW35678910121143210-1-2-3-4fliersmultiplehoppersswimmerssinglehoppersPCBschlorobenzenesDDTHCHsDDEPCBsCBzHCHsDDTsABPeBDEHxBCDTeBDEphosphatesFig.1.Majormodesoftransportofperfectlypersistent,hypotheticalchemical