Cellphone Radiation May Alter Your Brain.docx

Cellphone Radiation May Alter Your Brain.docx

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CellphoneRadiationMayAlterYourBrain

CellphoneRadiationMayAlterYourBrain.Let’sTalk.

IllustrationbyTheNewYorkTimes

ByKATEMURPHY

Published:

March30,2011

Inaculturewherepeoplecradletheircellphonesnexttotheirheadswiththesameconstancyandaffectionthattoddlersholdtheirsecurityblankets,itwasunsettlinglastmonthwhenastudypublishedinTheJournaloftheAmericanMedicalAssociationindicatedthatdoingsocouldalterbrainactivity.

Thereportsaiditwasunclearwhetherthechangesinthebrain—anincreaseinglucosemetabolismafterusingthephoneforlessthananhour—hadanynegativehealthorbehavioraleffects.Butithasmanypeoplewonderingwhattheycandotoprotectthemselvesshortof（gasp）usingalandline.

“Cellphonesarefantasticandhavedonemuchtoincreaseproductivity,”saidDr.NoraVolkow,theleadinvestigatorofthestudyanddirectoroftheNationalInstituteofDrugAbuseattheNationalInstitutesofHealth.“I’dnevertellpeopletostopusingthementirely.”

Yet,inlightofherfindings,sheadvisesuserstokeepcellphonesatadistancebyputtingthemonspeakermodeorusingawiredheadsetwheneverpossible.ThenextbestoptionisawirelessBluetoothheadsetorearpiece,whichemitradiationatfarlowerlevels.Ifaheadsetisn’tfeasible,holdingyourphonejustslightlyawayfromyourearcanmakeabigdifference;theintensityofradiationdiminishessharplywithdistance.“Everymillimetercounts,”saidLouisSlesin,editorofMicrowaveNews,anonlinenewslettercoveringhealthandsafetyissuesrelatedtoexposuretoelectromagneticradiation.

Socrushingyourcellphoneintoyoureartohearbetterinacrowdedbarisprobablyabadidea.Gooutsideifyouhavetotakeormakeacall.Andyoumightnotwanttoputyourcellphoneinyourbreastorpantspocketeither,becausethatalsoputsitrightupagainstyourbody.Carryitinapurseorbriefcaseorgetanonmetallicbeltclipthatorientsitawayfromyourbody.

Somestudieshavesuggestedalinkbetweencellphoneuseandcancer,lowerbonedensityandinfertilityinmen.Butotherstudiesshownoeffectatall.Giventhemixedmessagesandcontinuingresearch,RobertKenny,aFederalCommunicationsCommissionspokesman,saidinane-mail,“Asalways,wewillcontinuetostudythisissueandcoordinatewithourfederalpartners.”

ThephoneusedinDr.Volkow’sstudywasaSamsungKnack,modelSCH-U310,aflipphonethatwasinwideusewhenshebeganplanningherexperimentstwoandhalfyearsago.Buttoday’subiquitoussmartphonesemitevenmoreradiationastheytransmitmore,andmorecomplex,data.

YoucangetanideaoftherelativeamountsofradiationvariouscellphonemodelsemitbylookingattheirSAR,orspecificabsorptionrate.Thisnumberindicateshowmuchradiationisabsorbedbythebodywhenusingthehandsetatmaximumpower.AcellphonecannotbesoldintheUnitedStatesunlessanF.C.C.-approvedlaboratorysaysitsSARisbelow1.6wattsperkilogram.InEurope,themaximumis2wattsperkilogram.

TheSARnumberisnotdisplayedwhenyoucomparecellphonesatyourlocalwirelessstore,andtryingtofinditinthefineprintofyourusermanualisanexerciseinfrustration.TheF.C.C.maintainsthatSARvalues“donotprovidesufficientinformation”toreliablycomparecellphoneradiationemissionsbecausecertainphonesmightrarelyoperateatmaximumpower.Still,theEnvironmentalWorkingGroup,anonprofitorganization,hasacomprehensivelistoftheSARvaluesformostcellphonesavailablefrommajorcarriersonitsWebsite.（Forinstance,theAppleiPhone4islistedat1.17wattsperkilogram,theMotorolaDroidat1.5andtheLGQuantumat0.35.）

Butmoreimportantthanlookingforalow-SARphoneishowyouuseit.Manycellphonesemitthemostradiationwhentheyinitiallyestablishcontactwiththecelltower,makingtheir“digitalhandshake.”Toreduceexposureit’sbesttowaituntilafteryourcallhasbeenconnectedtoputyourcellphonenexttoyourear.

Duringtheensuingconversation,it’sadvisabletotiltthephoneawayfromyourearwhenyouaretalkingandonlybringitinclosetoyourearwhenyouarelistening.Thatbitofteeter-totterworksbecausetheemissionofradiationis“significantlylesswhenacellphoneisreceivingsignalsthanwhenitistransmitting,”saidLinZhong,assistantprofessorofelectricalandcomputerengineeringatRiceUniversityinHouston.

Moreover,yourcellphoneemitslesswhenyouarestationarybecausewhenyouaremovingrapidly—say,inacarortrain—itmustrepeatedlyissuelittleburstsofradiationtomakedigitalhandshakeswithdifferenttowersasitmovesinandoutofrange.（Morecausetohangupwhenyoubuckleup.）

Wantanotherreasontocomplainaboutyourcarrier’spoorcoverage?

Anysituationwhereyourcellphonehasaweaksignalindicatesithastoworkharderandthuswillemitmoreradiation.“Fewerbarsmeansmoreradiation,”saidOmGandhi,professorofelectricalengineeringattheUniversityofUtahinSaltLakeCity.Insidebuildingsandelevators,inruralareas,theGrandCanyon—thesearenotgoodplacestomakeacallifyou’retryingtoreduceyourexposuretoradiation.

Ofcourse,parentsusingtheiriPhonestopacifycrankykidsmightwanttoreconsiderrattles.Children’sdevelopingbrainsandtissuesarethoughttobemostvulnerabletocellphoneradiation.HealthauthoritiesinBritain,France,GermanyandRussiahaveallissuedwarningsagainstallowingsmallchildrentousecellphonesforextendedperiods,ifatall.

Therearecellphoneattachmentsthatpurporttoshieldusersfromradiation,andmostare“hoaxes,”saidMr.Gandhi.Bewareofpendantsthatsellersclaimsnatchradiationfromtheair.PongResearchoffersacellphonecaseforiPhonesandBlackBerrysthatitsayshasbeenshownbyanF.C.C.-approvedtestinglabtoredirectradiationfromthephone’santennaawayfromthehead.

Whilethemanufacturersaysitreducesradiationmorethan60percent,someelectricalengineeringexpertsquestionwhetherthecasemayhavetheoppositeeffectatorientationswhereyourheadisinthewayofthecelltowerbecauseyourphonemayhavetoincreaseitstransmissionstrengthsomewhattocompensatefortheredirectedsignal.Thecompanydisputesthis.Nevertheless,theneteffectofusingthedevicethroughoutthecourseofthedaymaybeareductionintotalexposure.

Texting,insteadoftalking,mightbesafer.“Thewholetrendtowardtextinginsteadoftalkingoncellphonesisprobablyagoodthing,”saidMr.SlesinatMicrowaveNews.

Thatis,ifyoudon’trestyourcellphoneagainstyourbodywhiletypingoutyourmessage.

AversionofthisarticleappearedinprintonMarch31,2011,onpageB9oftheNewYorkedition.

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