AssociationofStateandTerritorialDentalDirectors
FactSheet
NaturalFluorideinDrinkingWater
ThisfactsheetwaspreparedforStateandTerritorialDentalDirectorstoassistinprovidinganswerstocommon
questionsaboutfluorideoccurringnaturallyinprivatewellsandgroundwater.
Howmuchfluorideisfoundnaturallyindrinkingwatersources?
Fluorideispresentinallwatersourcesatconcentrationsrangingfromminimallydetectibletogreaterthan10parts
permillion(ppm).Thefluoridelevelinriversandlakes(surfacewater)varies
widelyreflectingrainwatercontactwithwindblownsoilsandotherelements
Fluorideisthe
intheenvironment.Wellwater(groundwater)fluoridelevelsvarydepending
th
onthemineralsintherockandoresthatthewaterpassesthrough.Fluoride
13 mostabundant
inoceanwater(96.5percentofEarth’swater)istypicallyintherangeof1.2
elementintheearth’scrust.
to1.4ppm.
Partspermillion(ppm)is
equivalenttomilligramsperliter
(mg/L).Onepartpermillionis
comparabletooneinchin16
miles.
Watersourceswithhighfluoride
concentrationsaffectupto60
percentofpopulationsofPakistan,theAfricancontinent,Thailand,China,
andSriLanka.1,2IntheUnitedStates,lessthanone-halfofonepercentof
U.S.residentsoncommunitywatersystemshavedrinkingwaterthat
exceeds2ppmandlessthanone-tenthofonepercenthavewaterthat
exceeds4ppm.3WatersamplesfromColorado,analyzedwhenstudying
theassociationbetweenColoradochildrenwithyellow/brownstainsand
reducedtoothdecayintheearly1900s,foundhigherlevelsoffluoride
rangingfrom2to13.7ppmfluoride.4
Whoisresponsibleformonitoringfluoridefoundnaturallyinpublic/communitywatersystems?
TheSafeDrinkingWaterAct(SDWA)designatedtheEnvironmentalProtectionAgency(EPA)astheleadagency
responsibleforsafelevelsofsubstancesindrinkingwater.TheEPAisresponsibleforsettingregulatorystandardsfor
thequalityofpublic(community)drinkingwatersystemsdefinedaswatersystemswith15ormoreservice
connectionsservinganaverageof25personsdailyforatleast60daysinayear(forexample,parksandrecreational
areas).TheSDWAdefinesanyphysical,chemical,biologicalorradiologicalsubstancesormatterindrinkingwateras
“contaminants”regardlessoftheeffectorlevelofthesubstanceonhumanhealth.Drinkingwatercontainssmall
amountsofmanydifferentsubstancesbelowtheidentifiedregulatorysafelevel.EPAconsidersscientificliteratureon
healtheffectsofallregulatedsubstances,establishesamaximumlevelindrinkingwatertoprotectagainstadverse
healtheffects,andworkswithdesignatedregulatoryagenciesinstatestomonitorandenforcetheselevels.5
Whoisresponsibleformonitoringfluoridefoundnaturallyinprivatedrinkingwatersources?
FourteenpercentofU.S.residentsrelyonprivatewellsthatarenotregulatedbytheEPA.6Privategroundwaterwells
servingfewerthan15connectionsorfewerthan25personsfornomorethan60daysinayeararenotregulated.Itis
theresponsibilityofthewellownertoknowthequalityofthewaterandifitissuitableforhumanconsumption.The
EPArecommendswellsusedfordrinkingwaterbetestedonceeverythreeyearssincewaterqualitycanchangeover
time.TheU.S.GeologicalSurvey(USGS),thescienceagencyfortheU.S.DepartmentoftheInterior,foundthat23
percentofprivatewellsexceededtheidentifiedregulatorysafelevelforoneormorecontaminantsatalevel
indicatingapotentialhealthconcern.7Thesesubstanceswereprimarilyradon,arsenic,uranium,manganeseand
1
WorldHealthOrganization.FluorideinDrinking-water.pp:5-8.2006.
PetersenPE,LennonMA.Effectiveuseoffluoridesforthepreventionofdentalcariesinthe21stcentury:theWHOapproach.CommunityDentOral
Epidemiol.2004;32:319–21.
3
NationalAcademiesPress.FluorideinDrinkingWater:AScientificReviewofEPA’sStandards.2006;2:25.
4
Churchill,HV.OccurrenceofFluoridesinSomeWatersoftheUnitedStates.IndustrialandEngineeringChemistry.Sept1931.23(9)996-8.
5
EPA.DrinkingWaterRegulatoryInformation.https://www.epa.gov/dwreginfo/drinking-water-regulatory-information
6
U.S.CensusBureau.CurrentHousingReports,SeriesH150/07,AmericanHousingSurveyfortheUnitedStates:2007[PDF-642pages].U.S.Government
PrintingOffice,Washington,D.C.:20401,Printedin2008.
7
UnitedStatesGeologicalSurvey.USGSWaterScienceSchool.ContaminationinUSPrivateWells.2009.
2
nitrates.Thiscomparesto1percentwithexcessivefluoridelevels.Fewprivatewellownerstestforfluorideandare
likelyunawareofthepossibilityofhighfluoridecontent.TheAssociationofStateandTerritorialDentalDirectors
(ASTDD)recommendsthatprivatewellownerstesttheirwellsatregularintervalsfordrinkingwatercontaminantsof
significanthealthconcern.
Whataretherecommendedlevelsforfluorideindrinkingwatersources?
TheEPAhassetmaximumallowableconcentrationsoffluorideindrinkingwaterat2ppmtopreventenamel
fluorosisand4ppmtopreventskeletalfluorosis.8Fourppm,themaximumcontaminantlevel(MCL),isenforceable
bytheEPA,meaningthattheEPAconsidersitunusableasaroutinedrinkingwatersource.TheSDWArequirespublic
notificationwhenthelevelisgreaterthan2ppm,thesecondaryMCL.Inaddition,statesmaysettheirownstandard
forthelowerMCL.
TheU.S.PublicHealthService(USPHS)recommends0.7ppmastheoptimumleveloffluorideindrinkingwaterfor
reducingtheriskoftoothdecay,whileatthesametimeremaininglowenoughtoreducetheriskofenamelfluorosis,
astainingoftheteeth.AttheUSPHSrecommendedlevelof0.7ppm,therearenoadversehealtheffects.Morethan
117organizationsincludingtheUSPHS,CentersforDiseaseControlandPrevention(CDC),theAmericanDental
Association(ADA)andASTDDencouragetheadjustmentofthenaturallyoccurringfluorideleveltomeettheoptimal
concentrationforpreventingdentaldecay.
Ifthenaturallyoccurringleveloffluorideinasourceofdrinkingwaterisnotadequate,andthewatersupplycannot
befluoridated,fluoridesupplementsarerecommendedforchildrenatriskfortoothdecay.9Healthprofessionals
needtoknowwhenthefluoridelevelindrinkingwaterislessthantherecommendedleveltosafelyandeffectively
prescribefluoridesupplementsforchildren,thusmakingtestingofindividualprivatewellsnecessary.
Whatwaterfiltrationsystemsreduceorremoveexcessivefluoridefromdrinkingwater?
Removaloffluoridefromwaterisdifficultandexpensiveforcommunitywatersystemsorforprivatewells.Reverse
osmosisdevicesandwaterdistillationcaneffectivelyremovefluoride.NSFStandard58recommendsthat
defluoridationdevicesachieveatleastan80percentfluorideremovalratetobeconsideredadequate.10Activated
carbonfiltrationunitssoldforhomeusedonotremovefluoride.
RESOURCES
Aswithmanysubjects,therearescientificallyaccepted,evidence-basedfactsaswellassourcesoferroneousinformation
concerningfluorideindrinkingwater.Recognizedandreliablesourcesforscientificallyacceptedinformationinclude:
CentersforDiseaseControlandPreventionhttp://www.cdc.gov/oralhealth/
PrivateWellWaterandFluoride http://www.cdc.gov/fluoridation/faqs/wellwater.htm#q6
CommunityWaterFluoridation http://www.cdc.gov/fluoridation/
NationalAcademyofSciencesanditsNationalResearchCouncilathttp://www.cdc.gov/fluoridation/safety/nas.htm/
AmericanDentalAssociationwww.ada.org
FluoridationFacts
http://www.ada.org/en/public-programs/advocating-for-the-public/fluoride-and-fluoridation/fluoridation-facts
FluorideSupplements
http://www.ada.org/en/member-center/oral-health-topics/fluoride-supplements
WaterSystemsCouncil-WSCisanationalnonprofitorganizationdedicatedtopromotingthewideruseofwellsasmodern
andaffordablesafedrinkingwatersystemsandtoprotectinggroundwaterresourcesnationwide.Therearemorethan60
availablefactsheetsavailabletobedownloadedfree.(See:FluorideandWellWaterandWellWaterandFluoride)
https://www.watersystemscouncil.org/well-owners/wellcare-info-sheets/
Wellcarehotlineat1-888-395-1033orvisitwww.wellcarehotline.org
NationalGroundwaterAssociationathttp://www.ngwa.org/Pages/default.aspx
ConsumerFactSheetSample:AddressingSafetyConcerns,NewYorkCommunityWaterFluoridationat
https://www.health.ny.gov/prevention/dental/fluoridation/docs/safety.pdf
8
EnvironmentalProtectionAgency.QuestionsandAnswersonFluoride.(2011)https://www.epa.gov/sites/production/files/201510/documents/2011_fluoride_questionsanswers.pdf
9
ASTDD.FluorideSupplementPolicyStatement.http://www.astdd.org/docs/fluoride-supplement-policy-statement-january-28-2013.pdf
10
AcopyoftheNSF/ANSIStandard58canbeorderedfromthewebsite,http://www.nsf.org/regulatory/regulator-nsf-standardsFoundedin1944asthe
NationalSanitationFoundationandnowknownasNSFInternational,NSFfollowstheAmericanNationalStandardsInstitute(ANSI)standardsdevelopment
processtodevelopstandardsandtotestandcertifyproductsandsystemsthathelpprotecttheworld’sfood,water,consumerproductsandenvironment.