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1、PassageOneTheAffectofElectricityonCancerCanelectricitycausecancer?Inasocietythatliterallyrunsonelectricpower,theveryideaseemspreposterous.Butformorethanadecade,agrowingbandofscientistsandjournalistshaspointedtostudiesthatseemtolinkexposuretoelectromagneticfields
2、withincreasedriskofleukemiaandothermalignancies.Theimplicationsareunsettling,tosaytheleast,sinceeveryonecomesintocontactwithsuchfields,whicharegeneratedbyeverythingelectrical,frompowerlinesandantennastopersonalcomputersandmicro-waveovens.Becauseevidenceonthesubj
3、ectisinconclusiveandoftencontradictory,ithasbeenhardtodecidewhetherconcernaboutthehealtheffectsofelectricityislegitimate—ortheworstkindofparanoia.NowthealarmistshavegainedsomequalifiedsupportfromtheU.S.EnvironmentalProtectionAgency.Intheexecutivesummaryofanewsci
4、entificreview,releasedindraftformlatelastweek,theEPAhasputforwardwhatamountstothemostseriousgovernmentwarningtodate.Theagencytentativelyconcludesthatscientificevidence“suggestsacasuallink”betweenextremelylow-frequencyelectromagneticfields—thosehavingverylongwave
5、-lengths—andleukemia,lymphomaandbraincancer,WhilethereportfallsshortofclassifyingELFfieldsasprobablecarcinogens,itdoesidentifythecommon60-hertzmagneticfieldas“apossible,butnotproven,causeofcancerinhumans.”Thereportisnoreasontopanic—oreventolostsleep.Ifthereisaca
6、ncerrisk,itisasmallone.TheevidenceisstillsocontroversialthatthedraftstirredagreatdealofdebatewithintheBushAdministration,andtheEPAreleaseditoverstrongobjectionsfromthePentagonandtheWhitHouse.Butnownoonecandenythattheissuemustbetakenseriouslyandthatmuchmoreresear
7、chisneeded.Attheheartofthedebateisasimpleandwell-understoodphysicalphenomenon:Whenanelectriccurrentpassesthroughawire,titgeneratesanelectromagneticfieldthatexertsforcesonsurroundingobjects,Formanyyears,scientistsdismissedanysuggestionthatsuchforcesmightbeharmful
8、,primarilybecausethey30aresoextraordinarilyweak.TheELFmagneticfieldgeneratedbyavideoterminalmeasuresonlyafewmilligauss,oraboutone-hundredththestrengthoftheearth’sownm
