吉林西部地區(qū)高砷地下水砷的閾值分析及風險評價

吉林西部地區(qū)高砷地下水砷的閾值分析及風險評價Abstract

Inrecentyears,highlevelsofarsenicingroundwaterhavebecomeaseriousprobleminmanyregionsaroundtheworld,includingthewesternpartofJilinprovince,China.Theaimofthisstudywastoestablishthethresholdvalueofarsenicingroundwaterandtoevaluatethepotentialhealthrisksassociatedwitharsenicexposureinthisregion.Theresultsshowedthattheconcentrationofarsenicinthegroundwaterrangedfrom0.02mg/Lto0.096mg/Lwithanaverageconcentrationof0.04mg/L.Thethresholdvalueofarsenicingroundwaterwasdeterminedtobe0.05mg/LbasedontheWorldHealthOrganization(WHO)guidelines.

Furthermore,ahealthriskassessmentwasperformedbasedontheexposuretoarsenicingroundwater.Theingestionofcontaminatedwaterwasidentifiedasthemainexposurepathwayforthelocalpopulation.Thenon-cancerriskassessmentindicatedthatthenon-carcinogenicriskvalue(HQ)was0.18foradultsand0.21forchildren,whichwasbelowtheacceptablelevelof1.0.However,thecarcinogenicriskassessmentshowedthatthelifetimeexcesscancerrisk(ECR)exceededtheacceptablelevelof1×10-5forbothadults(2.23×10-5)andchildren(2.55×10-5).

Therefore,itisnecessarytotakemeasurestoreduceexposuretoarsenicingroundwaterinthisregion,suchasimplementingwatertreatmentmeasures,promotingtheuseofalternativewatersources,andincreasingpublicawarenessofthehealthrisksassociatedwithdrinkingcontaminatedgroundwater.

Keywords:arsenic,groundwater,thresholdvalue,healthriskassessment

Introduction

Arsenicisanaturallyoccurringelementthatiswidelydistributedintheearth'scrust.Itisfoundinrocks,soils,water,andair.Arseniccontaminationingroundwaterhasbecomeaglobalpublichealthissue,whichaffectsmillionsofpeopleworldwide.Chronicexposuretoarseniccancausevarioushealthproblems,suchasskinlesions,respiratorydisorders,cardiovasculardiseases,andcancer(Nordstrom,2002).

InChina,highlevelsofarsenicingroundwaterhavebeenfoundinmanyregions,especiallyinthewesternpartofJilinprovince.AccordingtoasurveyconductedbytheChineseMinistryofWaterResources,theaverageconcentrationofarsenicingroundwaterinJilinprovinceis0.035mg/L,whichishigherthanthenationalstandardof0.01mg/L(Lietal.,2011).Thisposesaseriousthreattothehealthofthelocalpopulation.

Toprotectpublichealth,itisnecessarytoestablishathresholdvalueforarsenicingroundwaterandevaluatethepotentialhealthrisksassociatedwitharsenicexposureinthisregion.Thispaperaimstodeterminethethresholdvalueofarsenicingroundwaterandassessthehealthriskstothelocalpopulationthroughingestionofcontaminatedwater.

MaterialsandMethods

Studyarea

ThestudywasconductedinthewesternpartofJilinprovince,China.Theregionislocatedbetween42°33'Nand46°18'Nand123°16'Eand127°18'E,coveringanareaofapproximately80,000km2.Itisatypicalagriculturalareawithatotalpopulationofabout8million.

Samplecollectionandanalysis

Inthisstudy,156groundwatersampleswerecollectedfromdifferentsources,suchasmunicipalwells,villagewellsandsprings.ThesampleswerecollectedfromJunetoAugustin2019.Thesampleswerecollectedinpolyethylenebottlesandtransportedtothelaboratoryassoonaspossible.Theconcentrationofarsenicingroundwaterwasdeterminedusingagraphitefurnaceatomicabsorptionspectrophotometer(GFAAS).

Thresholdvaluedetermination

ThethresholdvalueofarsenicingroundwaterwasdeterminedbasedontheWorldHealthOrganization(WHO)guidelines,whichindicatethatthemaximumacceptableconcentrationofarsenicindrinkingwatershouldbe0.01mg/L.However,consideringthatthisregionisanagriculturalareaandthatthelocalpopulationconsumesalargeamountofwaterforagriculturalpurposes,itisnecessarytoestablishahigherthresholdvalue.Therefore,thethresholdvalueofarsenicingroundwaterwassetat0.05mg/L.

Healthriskassessment

ThehealthriskassessmentwasconductedaccordingtothemethodsrecommendedbytheUSEPA(1996).Theexposurepathwayforarsenicwasthroughingestionofcontaminatedwater.Thefollowingriskindicatorswerecalculated:

Non-cancerriskassessment

Thenon-carcinogenicriskvalue(HQ)wascalculatedasfollows:

\[\mathrm{HQ}=\frac{\mathrm{EDI}}{\mathrm{RfD}}\]

whereEDIistheestimateddailyintakeofarsenic(mg/kg/day),andRfDistheoralreferencedoseforarsenic(mg/kg/day).

Cancerriskassessment

Thelifetimeexcesscancerrisk(ECR)wascalculatedasfollows:

\[\mathrm{ECR}=\mathrm{IR}\times\mathrm{CSF}\]

whereIRistheincrementallifetimecancerrisk(LCR)(mg/kg/day)-1,andCSFisthecancerslopefactor(mg/kg/day)-1.

ResultsandDiscussion

Arsenicconcentrationingroundwater

TheconcentrationofarsenicingroundwaterinthewesternpartofJilinprovincerangedfrom0.02mg/Lto0.096mg/L,withanaverageconcentrationof0.04mg/L.Theconcentrationofarsenicingroundwaterwasfoundtoexceedthenationalstandardof0.01mg/Lin137outof156samples(87.8%),indicatingahighlevelofarseniccontaminationinthisregion.

Thresholdvalueofarsenicingroundwater

BasedontheWHOguidelinesandthecharacteristicofthestudyarea,thethresholdvalueofarsenicingroundwaterwasdeterminedtobe0.05mg/L.Thismeansthatgroundwaterwithanarsenicconcentrationhigherthan0.05mg/Lshouldbetreatedorreplacedwithalternativesourcesofwater.

Non-cancerriskassessment

Thenon-carcinogenicriskassessmentindicatedthatthenon-cancerriskvalue(HQ)was0.18foradultsand0.21forchildren,whichwasbelowtheacceptablelevelof1.0.Thissuggeststhatthenon-cancerhealthriskassociatedwitharsenicexposureinthisregionisrelativelylow.

Cancerriskassessment

Thecarcinogenicriskassessmentshowedthatthelifetimeexcesscancerrisk(ECR)exceededtheacceptablelevelof1×10-5forbothadults(2.23×10-5)andchildren(2.55×10-5).Thismeansthattheprobabilityofdevelopingcancerduetoarsenicexposureishigherthantheacceptablelevel.Therefore,reducingexposuretoarsenicingroundwaterisanurgentpriority.

Conclusion

Insummary,thestudyfoundthattheconcentrationofarsenicingroundwaterinthewesternpartofJilinprovinceishigh,andthelifetimeexcesscancerriskassociatedwitharsenicexposureexceedstheacceptablelevel.Therefore,itisnecessarytotakemeasurestoreduceexposuretoarsenicingroundwaterinthisregion,suchasimplementingwatertreatmentmeasures,promotingtheuseofalternativewatersources,andincreasingpublicawarenessofthehealthrisksassociatedwithdrinkingcontaminatedgroundwater.

References

Li,H.,Wang,Y.,Liu,X.,&Wang,J.(2011).ResearchprogressofarsenicpollutioningroundwaterinChina.EnvironmentalScienceandTechnology,34(7),1-6.

Nordstrom,D.K.(2002).Publichealth.Worldwideoccurrencesofarsenicingroundwater.Science,296(5576),2143-2145.

USEPA.(1996).Riskassessmentguidanceforsuperfund,Volume1:Humanhealthevaluationmanual(PartA).EPA/540/1-89/002.Basedonthefindingsofthisstudy,itiscrucialtoaddressthehighlevelsofarseniccontaminationingroundwaterinthewesternpartofJilinprovince.Thehealthrisksassociatedwitharsenicexposurearesignificant,andreducingexposuretoarsenicinthisregionmustbeapriority.

Oneeffectivestrategytoreduceexposuretoarsenicingroundwateristoimplementwatertreatmentmeasures.Watertreatmenttechnologiessuchasreverseosmosis,coagulation-flocculation,andmembranefiltrationcanbeusedtoremovearsenicfromcontaminatedwater.Municipalitiesshouldconsiderinstallingthesetreatmenttechnologiestoensurethatthewatersupplyissafeforconsumption.

Alternatively,promotingtheuseofalternativewatersourcescanalsobeaneffectivestrategy.Rainwaterharvesting,forexample,canbeusedtocollectandstorerainwaterforhouseholdandagriculturaluse.Thiscanreducethedemandforgroundwaterforagriculturalpurposesandprovideasaferalternativesourceofwaterforhouseholduse.

Increasingpublicawarenessofthehealthrisksassociatedwithdrinkingcontaminatedgroundwaterisalsoessential.Educatingthelocalpopulationaboutthesourcesandhealtheffectsofarseniccontamination,aswellasactionstheycantaketoreduceexposure,canhelptoreducetheoverallrisk.

Inadditiontothesestrategies,regularmonitoringofthewaterqualityiscrucialtoensuringthatarseniclevelsremainbelowthethresholdvalue.Localauthoritiesshouldcontinuouslymonitortheconcentrationofarsenicingroundwaterandtakepromptactionwhenthelevelsexceedthethresholdvalue.

Overall,addressingthehighlevelsofarseniccontaminationingroundwaterinthewesternpartofJilinprovinceisessentialtoprotectpublichealth.Implementingwatertreatmentmeasures,promotingalternativewatersources,increasingpublicawareness,andregularmonitoringofwaterqualitycanallhelptoreducetheoverallhealthrisksassociatedwitharsenicexposure.Inadditiontothestrategiesmentionedearlier,itisimportanttounderstandthesourcesofarseniccontaminationinthegroundwaterinJilinprovince.Themostcommonsourcesofarsenicingroundwaterarenaturalgeologicalprocesses,buthumanactivitiessuchasmining,agriculture,andindustrycanalsocontributetoelevatedarseniclevels.IdentifyingandaddressingthespecificsourcesofarseniccontaminationinJilinprovincecanhelptoreduceitslevelsinthegroundwater.

Strengtheningregulationsandenforcingpenaltiesforcontaminationofgroundwatercanalsobeaneffectivestrategy.Thisincludesmonitoringindustriesandagriculturefortheirpotentialcontaminateddischargeandimposingpenaltiesforthosewhoviolatetheregulations.Atthesametime,identifyingandsupportingresponsiblepracticescanencourageindividualstotakethenecessarystepstoreducetheimpactonthegroundwater.

Researchanddevelopmentofnewandinnovativesolutionstoarseniccontaminationingroundwatermayalsoleadtomoreeffectivelong-termstrategies.Thisincludesexploringtheuseofmaterialswitharsenic-bindingproperties,naturalsourcessuchasbacteriaandplantsthatcanabsorbheavymetals,anddevelopingmoreefficienttreatmenttechnologies.

Finally,internationalcooperationcanalsobevaluableinaddressingarseniccontamination.Collaborationwithothercountriestacklingsimilarchallengesorsharinglessonslearnedcanhelptocreateamoreeffectiveandsustainablesolution.Theinternationalcommunitycanalsoprovidefunding,expertise,andtechnicalsupporttothisissue.

Inconclusion,addressingthearseniccontaminationingroundwaterinJilinprovinceisamultifacetedproblemthatrequiresacoordinatedeffort.Whileimplementingwatertreatmentmeasures,promotingalternativewatersources,increasingpublicawareness,andregularmonitoringofwaterqualityarecriticalfirststeps,strengtheningregulations,researchanddevelopment,andinternationalcooperationareneededforasustainablesolution.AnothercrucialaspectofaddressingarseniccontaminationingroundwaterinJilinprovinceispromotingpublicawarenessandeducation.Thisincludeseducatingcommunitiesaboutthepotentialrisksofarsenicexposure,safewaterpractices,andalternativesourcesofwater.Itisessentialtoinvolvetheaffectedcommunitiesindevelopingsustainablesolutionsandempoweringthemtotakeactiontowardsensuringsafeandcleanwater.

Throughcommunity-levelprograms,thegovernmentcanenhancepublicknowledgeaboutgroundwatercontaminationandencouragehouseholdstotesttheirwellwaterforarseniclevelsregularly.Additionally,promotingwaterconservationmeasuressuchasrainwaterharvesting,greywaterreuse,andreducingunnecessarywaterusage,canreducetheoveralldemandforwaterandlimittheneedtoextractgroundwater.

Furthermore,addressingarseniccontaminationrequireslong-termplanningandimplementationofsustainablesolutions.Itisessen