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4. What are the results of the research
done already?
Theresearchdonethusfarhasproduced
conflictingresults,andmanystudies
havesufferedfromflawsintheirresearch
methods.
Animalexperimentsinvestigatingtheeffects
ofradiofrequencyenergy(RF)exposures
characteristicofwirelessphoneshave
yieldedconflictingresultsthatoftencannot
berepeatedinotherlaboratories.Afew
animalstudies,however,havesuggested
thatlowlevelsofRFcouldacceleratethe
developmentofcancerinlaboratoryanimals.
However,manyofthestudiesthatshowed
increasedtumordevelopmentusedanimals
thathadbeengeneticallyengineeredor
treatedwithcancer-causingchemicalsso
astobepre-disposedtodevelopcancer
intheabsenceofRFexposure.Other
studiesexposedtheanimalstoRFforup
to22hoursperday.Theseconditionsare
notsimilartotheconditionsunderwhich
peopleusewirelessphones,sowedon’t
knowwithcertaintywhattheresultsofsuch
studiesmeanforhumanhealth.Threelarge
epidemiologystudieshavebeenpublished
sinceDecember2000.Betweenthem,the
studiesinvestigatedanypossibleassociation
betweentheuseofwirelessphonesand
primarybraincancer,glioma,meningioma,
oracousticneuroma,tumorsofthebrainor
salivarygland,leukemia,orothercancers.
Noneofthestudiesdemonstratedthe
existenceofanyharmfulhealtheffectsfrom
wirelessphoneRFexposures.
However,noneofthestudiescananswer
questionsaboutlong-termexposures,since
theaverageperiodofphoneuseinthese
studieswasaroundthreeyears.
5. What research is needed to decide
whether RF exposure from wireless
phones poses a health risk?
Acombinationoflaboratorystudiesand
epidemiologicalstudiesofpeopleactually
usingwirelessphoneswouldprovidesome
ofthedatathatareneeded.Lifetimeanimal
exposurestudiescouldbecompletedina
fewyears.However,verylargenumbersof
animalswouldbeneededtoprovidereliable
proofofacancerpromotingeffectifone
exists.Epidemiologicalstudiescanprovide
datathatisdirectlyapplicabletohuman
populations,but10ormoreyearsfollow-up
maybeneededtoprovideanswersabout
somehealtheffects,suchascancer.This
isbecausetheintervalbetweenthetimeof
exposuretoacancer-causingagentandthe
timetumorsdevelop—iftheydo—may
bemany,manyyears.Theinterpretation
ofepidemiologicalstudiesishamperedby
difficultiesinmeasuringactualRFexposure
duringday-to-dayuseofwirelessphones.
Manyfactorsaffectthismeasurement,such