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ST9302-CS 940920Sept 20, 1994 !, '-, Ms. Jean Murph Citizens' Advocate -: Coppell. TX Dear Ms. Murph: I enloyed your last editorial on the powerline tssue. Thanks for sending it. As I mentioned on the phone, my husband and I recently sold our house in Arlington so we could move to Coppell. Unfortunately, our h~use was being built on Sandy Lake Road. We still want to move to the city, but we are now looking in other neighborhoods and remain very interested in this controversy involving Sandy Lake. I think it affects the whole town, and should be of great concern to anyone living there. In your column, you raised some good questions that people need to think about: 1 ) Should TU be the main source of information for what can/must be done with those lines? 2) Wouldn't it be better to scale back the roadway, if that would keep giant power poles out of the median7 If Sandy Lake were built with a narrower median, the poles could be left where they are. The city engineers office tells me that the roadway as planned would end up about two feet beyond where the poles are now. If that' s true, then a few feet taken out of the proposed wide median - six feet? eight feet7 - might be enough to leave the utility easement alone. If the city stayed with the status quo, with regard to those poles, then TU would have to ne,,otiate any. voltage increases apart from the road issue, and perhaps pay its own f;eight to relocate the lines, should it decide to increase the voltage. I'm told that there is a 90 to 100 feet easement across Sandy Lake, depending on where you are. That's enough easement for 138 KV line, according to the Public Utility Commission in Austin. But that 100 feet only works as the appropriate easement - with 50-feet on either side of the power lines - if TU*s poles are located in the middle of the road. Therefore, it follows that if the city refuses to shift TU's easement to the middle of the road, t.he utility would be forced, for now, to keep the lines as they are, at a lower, safer voltage. A 138 KV line simply doesn t "'ht'~ on the south side because there' s not enoup_,h clearance from buildings on that side of the ro.L?~If TU wanted to increase the power at that site, it would probably have to s~e~ special clearance and permits from the PUC, accordin~ to an engineer I svoke with. The public could protest that, and the would likely reject any variance from the normal 100-feet easement. The implications seem clear. If the city doesn't tinker with the present easement, TU is left to figure out its own future. This status quo approach would help all of Coppell by keeping unsightly power poles out of a key residential roadway. Yet, Sandy Lake could still be widened, albeit less grandly. Best of all, such a policy would serve the neighbors on both sides of Sandy Lake Road by protecting their health and property values. And it wouldn't hun TU, because the utility could remnt~ thase lines should it ever need to upgrade the power they carry. Rerouting, according to the PUC, is quite common. For those who might be concerned that a scaled back Sandy Lake would not be as aesthetically appealing as the original plan, it might be helpful to know that utilities in other pans of the country no longer encourage, and in fact, discourage, recreational uses under power lines. In other words, the idea of having bike paths and hiking trails is fast going out of fashion and may, in fact, soon be considered a public health hazard. The Bonneville Power Administration in the Northwest, which has done extensive research on electromagnetic fields, has banned all recreational uses of powerline easements and adopted the federal government' s advised ~prudent avoidance" policy, encouraging people to reduce their exposure to electromagnetic fields when they can be easily and inexpensively do so. The trend, in other words, is to err on the side of caution. It is a trend worth following for legal, as well as health, reasons. Keep up the good work. Barbara Kessler Irving, TX PS - The engineer with the PUC is Ed Ethridge - 512-458-0398 Bonneville Power puts out several free pamphlets on EMFs. 1-800-622-4519 // cc - Tom Morton:/Candy Sheehan, Lanny Mayo, James Witt '~; Should n the 1970s. Culorado epi- electromagnetic ~elds--EMFs. for changes in cellular activity. In some . demiologist Nancy Wer- short--surrounding almost any dec- cases. they've shown that exposing ,: yOU worry theimer set out to study trical conductor. whether it's a trans- animals to high-intensity fields can '~ '" abOUt thelTI ? childhood-cancer panems mission line. household wiring, an cause biological changes--for exam- . .~;~ ,n the Denver area. After several appliance, or an electric blanket. pie, promoting the growth of breast · Scientists false starts, she decided to test the While the hazards from these fields tumors in rodents. But it is far from still don't theory that exposure to the electro- may or may not be significant, the clear whether, or how, similar magnetic fields around power lines fear of them is. In state 'after sate, changes might occur in humans. X~.{, knOW for was somehow related to the develop- nervous citizens have delayed or Moreover, few of the studies have :!!q sure. VVe tell meat of childhood leukemia. even killed electric' utilities' plans to passed the most basic test of scien- The preferred procedure in epi- build or expand high-voltage trans- ti~c validity: being replicated in ~'~' yOU What demioloSy--studies of human dis- mission lines. Real-estate brokers somebody else's laboratory. !: studies have ease patterns--is to compare people report that houses next to power At this point, enough evidence . who have been exposed to a pn~ lines sell more slowly than others. suggests a possible health hazard to ShowR~and sumed risk with a 'control" group of and for lower prices. Parents with justify taking simple steps to reduce give prudent similar people who have not been ex- children in %hools near power lines your exposure to electromagnetic posed. Comparing smokers and non- are- demanding that either the fields. The larger dilemma is wheth- advice. smokers. for instance. br, mght to schools or the lines be moved. er the risks justify making major light the lung<ancer risk posed bv Meanwhile. lawsuils by cancer vic- changes in our huge. complex eleetric- tobacco. But since everyone uses tires against power companies m:e power system--changes that could electricity Wefthelmet didn't haw a making their way through the courts disrupt the reliable. relatively inex- group to use as a control. in many sates. Keith Horig. a pensive electric service Americans She and her cl~lleakme Ed l~eper. Washington. D.C., engineering pol- have come to take for granted. a physicist. fi>und a solution when icy analyst. estimates that this "dec- the>' realized that certain con~gura- trophobia" is already costing the U.S. JIll[ [llls~t.S tions of outdoor high-vulta~e power some .';1-billion a year in reduced The electric-field component of an lines produced hi~zher-than average phipetty values. hi~her electricity F. MF is shielded by building mateft- t4ectronta.~xnetic fields in nearby rates. and litigation expetlses. ats and has not been of much con- houses. Using titis inh~rnmuon. Wcr- Is the concern justified? Nut even tern. Questions have focu~d instead theliner and l-eel>er devisud a "~qre the best-informed experts ca say for on tile magnetic-field component. code" that led them to label house... sure. Neither the original study hy Magnetic fields pass easily through as high-fie c .r Iiwv-th.ld just by h.,k- \V~.rtheimer and [.ceper nor tht' epi- almost an>thing, including buildings ink m the size and ll,cati, ,. ,d' p.w~-r dtmi.h~;:.ica! studi,.s titat fi~llow~.d and file human body. lines in ttw area. They lilund that have added up t,, scientific certainly. TIle alternating electric cuffed children iMmZ in "hi~zh wit,. o>de" i;fi~, rat, 5' -tudies haven't been delivered by the American power }muses w,..re about twice as likHv tt, ven. helpfill tql}ter. though that's u~,t '%vstem goes through a complete dcv,.l,q~ leuk,.mij a> fi~l;se in "1-'~ knttlstla] ,qli-, ,';u'lv iu ih,- sin t~ of a cycle 60 tiules per ';econd. a rate wire c,,l],." !loll>e- '%'i,qjt-iI]c p'rk-I!,,men.,n. ~,, L,r. Jab known as liO hertz (Hx). The associ- :~dld s{, al~l,thcr l,'m ,.'.,is jli, i..] '.,, 'quill,.- ]~,','t. ;h,,'.'..'l fil-:it &',_tr,.na~-ated nlagnet]c I]eld changes ctirec- ,'.l'.~ !ist !, ',.n',in ,rml~lxt.;; ',~,,rrj,-: tt.~ln~[~c +i~.'.d- t':v/~ t)rl~dtl.cP nlt~:i-;urablc~i,;n b, vice even_' cycle. 354 CQNStjMER REPORTS MAY ' er in prolxwtion to lt~e strenglh of Savilz als- l,{~ked al ctnildhf~,d 2'Wv;~r i.,'!-i,,d ;unnn:: -. >!~{-"Z" the current. and their intensity falls canct-r cast..'. ill l),'nvcr bul u>cd i! hl;t],.' ,'h'ctl ic t:tilitv ~, .ri-.I.r~ in '. ,~ff quickly wilh distance from the better design: !w hired v,,rkt rs t,., :tdd culd f:rzm,,.. l'h,' source. assign wire co<h,s t{i huu~,,s blindly, oiHained adual ~orkIfiact. measurt. U.S. homes typically have a "back- and to ~neasure tbc indl>or ~d,ts in ments bv bavin~ svvcral tht~tl,salld ground" field level rm~ging from O. 1 most houses directly. 'I'he results {'s- . ............................ to 2 milligauss (raG), the standard ~n~ally c,,.~,~,~ed W**nh~'i,.er's POWER UIIES: 'lOOI {RI'I' BELOW?. unit of measurexnent for magnefic ~udings: Children IMng in high wire . . :"'- fields. Epidemiologic research on ex- co(h: houses w~lrc r,,ughly ~v.-ice as Because transmission lines havo posure to EMFs, then. has focused likely to get leuktqnia. Surprisingly, rod h3r [liblie eonllorrt, on~eldsmeasuringabove2or3mG. thougb, theactualnwasurenwnts,~f ~lorwayslo One source of household fields is indoor fields were not linked to nearby power lines and neighbor- leukemia, ~ some queslions about hood dislribulion lines. Although the study's meaning remained. Anothot is to I:mni tham. fields directly under large transmis- Similar results--showing aboul a ~ ITta{lntClie sion lines can be more than 50 mG. doubling of leukemia risk for chil- fan tic they diminish rapidly with distance dren living in houses with fields of tlmC~! IllOh other out. (see the box at righ0. One hundred 2 mG or more--were rel~wted in 1992 hibith~}' e. lcptmsi~e in nlanlf'lS~l$. ' yards away from even a big, 500- by Swedish researchers. Their study ~ ~ I!!~ I0 kilovolt line, the field might be only was considered an improvement lint¢ so Ihlir 1 raG. Neighborhood lines may look over earlier ones because it era- .builtl less threatening, but they pass much ployed a more accurate measure of ~/'OUnd.l!lali. ' .'.....: closer to houses and can sometimes magnetic-field exposure than the ,~e~ ,~" produce indoor fields of 2 mG or wire codes used in the Wefthelmet th~ Uii~'ifgk~'$ ~ more. Another source of fields is the and Savitz studies. Using their coun- grounding system that protects rest- try's unusually detailed utility rec- dents from lightning and electric ords. the Swedish scientists were shock delivered by a faulty appliance. able to calculate what the fields had ~ Other Most modern wiring adds little or been years be~re in houses near nothing to a household's background electric lrm~smission lines. · ".,' .'~'.:--. field level That's because the circuits Of the 11 childhood-cancer studies .~. consist of two wires carrying current that have been conducted. six--the , ~: ~ I l[i kilO¥Olts, 65 FEH HIGH in opposite directions, and when three studies just mentioned plus !"~} such wires are placed close to each three others done in Los Angeles. :" ~ · other, their fields tend to cancel each Denmark. and Finland--are consid- other out. A number of common ered by experts to be the most care- I: - appliances can generate relatively ful and thorough. Of tho~ six. five ~ 2:30 kilO¥OltS, 85 I:EH HIGH strong magnetic fields, but the fields' found some statistical association intensity generally diminishes to neg- between elevated magnetic fields and L,.~,.; .g' ligible levels a few feet away. childhood cancer. ':~.,... .... .{jr . For an overview of fields around A few other studies have tried to the house, see pages 356 and 357. determine whether adults who live ~:~ near power lines haw. an increased ~. Reseafdl Illui h~b cancer risk. Here, however, the re- ~ Because Wertheimer and Leeper suits have been inconsistenl. The '; liOO kilOVOltS, had very little money for their Den- studies may have been muddied by :.%, ver study, they couldn't afford the the fact that adults coukt haw been : %~ , . _. equipment or staff necessary to mea- exposed to magnetic fields at a pre- : ,' '-% - .~ sure actual magnetic fields inside the vious residence or on the job. houses. Nor could they afford to hire Many studies have looked al can- , an assistant to assign wire codes cers in adulls, such as utility and rail- "blinclly'--that is, without knowing road workers. wtm were presuniably - ...................... which houses had been home to chil- exlx~sed tu strong ma~.metic fietits on ' · < "%":" >~-~-'~-~";~'} dren with leukemia. Instead. they did lhe job. ()nee again. the resu Its bare possibility that subconscious bias led ins excesses of brain cancer and lea- [iOI..J move away horn hCh- them to assign high wire codes to kemia and others finding n,mv. But ne$. TI'~ lilies' rrla{]Fleti~ fields houses that they knew were linked lhnse studies based estimates .fex- stantiaily as elc:~'tric utilities va~:lhs ' to cancer cases. Because of these posure on job tith~.s. [lot on ilt'ltlill I>llOf current sent. According to tho methodological flaws. and because of the-job nulasuremi.nls. and ifflen POwer Administration, the msasurm'nantS the implausibility of their findings. lacked infornlaliun . ,rl hm~ hmt[ the above occur dudnO typical loads. Wertheimer and L¢~'per's study, pub- study ':ubjecls h:td hdd their jiib- CONSUMER REPORTS MAY 1994 workers wear magnetic-field record- fields can vary gready o~'er thne ae- . ing meters for an entire work week. Wnding on me ~wer loads in ne~by ~~~' ~ey ~so reconsNcted the subj~'ts' lines and neighboring houses. past exposure through detailed era- Skeptics. on ~e o~er hgd, ~e ~e study found no overall in- ne~c fields don't co~elate ~th di~ crease in cancer risk among those ease because ~ose fields reply don't fields. It did, however. find about a something else must explm me cor- ~ofold increase in the risk of devel- relation be~een ~re codes ~d c~- oping a ~ of adult leukemia called cer--some as-yet-un~own ~con- acute nonl~phoid leukemia gong rounding factor" ~at is related to ,~ % due to be published later ~is ye~. while ~e low-risk hours away from T~en toge~er, ~e octmpa~on~ ~wer lines were ~ newer, more ~ '~ ~ ~d residential studies done to date suburb~ neighborh~ds- ~e ~ner- suggest that exDsure to s~onger- ciW neighborhoods could have m~y ~. ~-average ma~e~c fields may o~er engomen~ h~ds besides s~gh~y increase ~e risk of develo~ s~ong ma~e~c fields, such ~ ~- ing some gs of leuke~a. ~e e~- dus~ emissions or hea~ ~c. dence for ~ association ~$ other But no one ~ows what cau~s - ~s of ~cer is f~ less cle~. childhood leukemia, which m~es ~e ~ch for a coNounding factor ~~ ~ ~ as much ~esswork as ~ence. Not ~ a g re~ ~at w~ dr~latM su~singly, ~e ~ch ~ ~ has but never o~ci~ly relea~d, ~e U.S. come up erupt. En~ronmen~ ~otec~on ~enq A ~cond problem ~ ~e epi- concluded in 1~ ~at ~Hz mag- de~olo~ is ma~ema~cM: C~ld- ~ ~ nefic fields were "a possible, but not hood c~cer is ge to ~n ~. proven, cau~ of ~cer in hum~s." ~e Swedish s~dy cme up ~ 39 ~ 1%2, re~e~ng ~e ve~ ge ~s of leuke~a, over a 2~ye~ This old house rese~ch, a p~el conven~ by ~e ~od, ~mng 127,3~ c~dren who The spa¢in~ ol gite House ~ience ad~r found had lived ~in 3~ mete~ of high- the wires in this old-fashion~ "no con~ncing e~dence" ~at ~e voltage ~smi~ion ~es. gen knob-and-tu~ fields ~d a he~ h~d. re~che~ ~e wor~g ~ such a Such ~ m~ ~e no doubt sm~ number of ~s, it ~ ~ ~- wirin~ can duce fields of puzzling to homeo~em wondering ~culL ma~emafi~Y, to ~te 7 mG or more a whe~er to be wowed. How could ch~ce v~afions from reM eff~ few l~t away. res~nsible ~ienfists reach such Finely, epide~olo~sts ~e not dffierent conclusions? even ce~n ~ey ~e s~d~g ~e Much of the unce~n~ cente~ appropriate as~ of el~Womg- on whe~er ~e smfisfic~ association nefic fields- Most have look~ at a be~n hou~hold ma~e~c fields ~r~n's average ex~sure to fields ~d childhood c~cer is me~in~l over time. But what ff ~e cfifi~ or a fluke. ~e findings of ~e ~E factor ~ms out to be ~casionM ex- presented a p~adox. Re~chers fields ~in a ce~ rage of inten- using ~re codes or other ind~ect si~? Bo~ of ~o~ ~ssibiHfies have ; ways of measuring ma~efic fields ~nsu~est~,but nei~er h~n have found a Bnk be~een ~ose studied indep~. measurements and childhood can- {1~ in ~ hb cer. But when rese~chers actually measure ~e ma~efic fields ~thin ~ough epide~olo~ c~ sug- houses direc~y, the link f~ls to gest a cau~ connection, only lab~ ap~. % f~, not a single study has rato~ ~d cU~cM re~ch c~ mined up a statistically si~cant &nch it ~ere have been m~y ments of household magnetic fields egects of ~temafing ma~efic fields gd any fo~ of cancer. --but no~ing approaching a con- Some scientists ar~e that ~re vincing demons~afion of how ~ey codes are actu~ly a better overidl might endanger he~. indicator of exposure to ma~efic On the face of it, ~Hz ma~e~c fields than real, indoor measur~ fields would seem unEkely to do ~y- ments are. In the indoor studies, thing at all inside the body. people's measuren~ents have been taken for ~ bodies ~e already ~ive wi~ elec~- 2 l h{ mrs at most. And magnetic cal ener~'; it makes our hea~s beat PLUG-IN ANALOG CLOCK HEATED WATER BED OR ELECTRIC BLANKET [] ~ I ELECTRIC BASEBOARD HEAT ~ BLOW DRYER , . - , ....,, t9 CURRENT EVENTS If currents entering and leaving a house are not exactly equal, the ~mbal- through the house the current returns to the panel. Normally. it trav- ance can create a magnetic field along the senrace drop. where electr~c~t,;' ~s els back out to the street But some current may ~nstead travel on the fed to the house. Hero's how that happens Electric sen/~ce b/pmalJy comes grounding ','v~re ~ attached to the hOdSOS water p~pes [:]. The d~verted to a neighborinood on an overhead dlstnbdtlon line ii A transformer [~] cdrrent then travels along an underground water poe [z] to the ne~ghbor's reduces voltage for transm~sswon to the senvice drop ~ Current passes house [] incon~!ng and outgoing currents are thus unbalanced along through the meter [] and fuse box or circuit-breaker panel [h.J for d:sm- the houses and the ~'erghbOr s service drops [] and [j]. producing bution to the house's outlets and fixtc, res [.'] After compiet ng ~ts route beids tea' both' drops of 5 mG o~ more {)I1C a~xli)thvr. Xl irrt)vcr. ~.tiz Iliad- ~V)lcI/cell< in a lab, ,uat,,O' arc nfitlcr<, and the actMb' of hllinulle- ndic fluids art' iar too f~'cl>h~ t,, dis vxp~ sr [o magnetic fidds. ttw fluids ~vstem calls. However. many of the rupi mtfiecular bonds. as X-rays and in~ ucc tiny r'lcctNc curt'cuts bchvccn lab experiments have been con- ~,ther radioactive e wr,k3' c~m. ,r cvd~ thc cells. Scxcl'aJ experiments havt' dueted with ~ekts dt~zcns of times heat tissues. as stmn~ micr{,waves shuwn thal "st nwth ng is gutrig on in stnmger than lhose tt) which hu- and radio waves can. those Iwtri dishes" under th~se con- roans Lwe ordinarily exposed. Because magmelic fields calfl ditkms. says Jack Adams. a rcse:~ch It's uncleg whether cellul~ break molecular bonds. scientists on fcllow in tht' Dependent of En- changes in a pe~ dish translate into all sides of the issue agree that the ginecring and Public Policy at Car- cellul~ charges ~ a 1Mng orgaism. fields probably do not directly cause ne~e Mellon University. Magme~c Europea studies tff rodents ~th cells to become cancerous. ~ther. fields can. for ins~ce. ~Dct the chemically induced breast cacer they may promote the development functioning of the cell membrane. ,have sho~ ~at ~e c~cers seem to . gow faster in ex~emely intense ma~efic fields. But o~er aim~ , IIG Ells It II studies have tended to show that ~y~~~w~velsy~ ~er ~l~'t u~ ~ ~ i::~':2~ Recenfiy, some resetchefs have ~ ~ ~ r~ e~. M~y g~ oI ~ ~s. ~7: ~' ' .... ~;~::~ suggested that ma~e~c fields may ~ ~ ~ fi~s ~ ~e~ ~ ~~- influence heal~ by me~s of a hor- n, ~ ~ ~ ~ ~ y~ u~ Mean ~ ~e ~ ~ ~e "~k ~s" ~:;~,~::~:' mone c~led melato~n. Melatonin is . ~ ~ h~ ~r ~ is ~ Ifs en~ ~~4:~"~ ~a-sized org~ ~side ~e b~n that ~ ~ ~ ~ ~o~ ~ Yn $, ~y, 7 ~ ~ ~:~~:(~ is exq~sitely ~nsi~ve to Ught ~d o~~~~ .~, ~d 1 mG ~ ~ ~s;[T~:~(~ d~k. It produces melatonin only in 'y~~a~~,a~ ~, it is ~ ~ ~ ~-~-~:~j d~ess. Daynght suppres~s mela- -~.~ ~ ~. G~ ~~~bb~~'~ toninproduc6on,~drecent~imj ' ~ ~ ~' ~~. :).:::<f~'~':.~.~:~ rese~ch has suggested ~at mag- ' ' ~i ~ a n~ But ~ ~ ~':~:~ 'T~ neUc fields c~ suppress it as well. ~ ~ ~ M~ a ~ s~ ~~"~ ]: ':~ In ~imJ ~d test-robe exFd- · To a tom ho__ to hap get ~d of fleera&c~s,sub : / ~ ~ yn Fm~~ --- ' - ~::": smces ~at c~ d~e ceBs ~d .... _% ~m ~, yo~ or have ~e ~n ~?'. ' i ':~::~ dise~s, ~cluding c~cer. ff mag- : h~ever~d ~ ~ ~ de~ ~ ~e~::~ ." ~;';'~ ne~c fields do suppress melato~, ~,. ~s not ~ c~ pr~e ~~ "~ they ~ght m~e it easier for c~cer- ' ~.~ --y~ ~ ~t rea~s, such as ~m ~'~ ~ ~ ous cells to gow unch~ked. ;' "' ' ~ ~ w~ p~e where el~ ~ ~h~,, ':: ~ere is only sketchy evidence "~d' ~e e~n~ ~d Me~ements shou~ ~ ~ ~:~e ~ that ma~efic fields ~ect melatonin -- ' ~ble. you s~nd khe m~t ~: ~ ~ ?' levels in people. Md ~e ~o studies We gha~ a r~ ~mhen. gm~, g hL~ ". that suggest this--neither of which ' has been replicated--also surest .... ~l~on d gau~gt~ where a ~ght is con~oB~ by m or ~ -: ." g ~ { 1~ $~ 8~, ~d s~es, ace ceg ~ a ~ that only ce~n ~dMdu~s ~e sus- C'-,~, , ~ ~ ~k~ ~ ~ ~o~ c~its ~ ~'~' ~S' '? cepfible to theproblem. ~:~: ~- g~ s~er ~ough~t a r~m.  How roefly to ~ ~em Wo~ng ~pJe ~ } ~ ~': L~ ~ risk ,. milligauss? out at a hou~ ~ek empby~ could ~ ~ ~ ~;-' ~g~e studies now ~der way , 4ncB~g a gf~on C~vemmnt- .~ Gaussmeters b~t by ~e office. ~e coger~ b~:,.~' ~ may be easy to El~ffic Power quen~ have ~m~ ~ ~ sponsored rese~ch i~fiafive~may hold, but we Re~ch h~ ~ms ~at c~ genem~ e~me~ gO~' eveninny resolve some of ~e uncer- found it hard to mm ~P~ h fields ne~y. h ad~fiom ~ ~g ~ rainties leg by earner research. In use the ones we ~nox, M~. c~ produce higher fidds ~ ~d~ the meafime, there are some level- tried in a way ~is model ~ng, $d ~me eq~pme~ ~ch ~ ~ headed ways of dealing with electro- h~ w~ de puter monitors ~d copiem ~ ~ s~- n~a~etic fields. that produced an '[~e first is to keep the risk in per- accurate reading. si~ed sg~- rounded by ~gh fields. c~y for r~ Since ~ienfists don't ya ~ow e~c~ spective. 'l~e re ~e about 2600 new se~chers to what s~en~ of mge~c field is a$~d cases of childhood leukemia s~dy ~e beha~or of residential m~efic ~ heath effecB, it's not ~bte to ~ ve~ in the U.S. q~e chance vf a fields. Un~e ~ ordin~ house, where a "sge' level. We do ~ow, however, ~at ~ ~ivcn child's developing leukemia in fields v~ over time, ~e fields at ~e EP~ ~rcent of U .S. houses have a ma~e~c field anv vt'ar is about one in 2~ ).l D0. with hou~ ~e s~bl~d thus were ideal for of 2.1 mG or less when readings from ~e th~ imlk uf cases occur~n.~ by our ~s. center of each room ~e averaged. age of five. Stow epidcm its have 5ugg,,stcd that musual!v CONSUMES REPORTS MA'( 1994 358 .......... --, COMPUTING, COOKING, COVERING, CALLING . SPECIAL RISKS IN DAILY LIFE? a child's risk, raisin~: it ~o om~ in 10.{X}0. But even in those studies, the vast majority of leukemia cases oc- Four fixtures of modern life~the computer, and his colleagues at the Uniw~rsity of North curred in houses calculated to have the microwave oven, the electric blanket, and Carolina rt;porled that children whose moth- low mag~wtic fields. the cellular phone--have come under suspi- ers slept under such blankets during preg~ In the end, parents must make a cion because of the electromagnetic fields they nancy had a 70 percent greater chance of personal decision about how much to create. Here's what research has shown. developing leukemia than did children whose worry--just as they routinely choose mothers used regular blankets. Like other to worry about or ignore other risks Computers such studies. this one should be interpreted in their lives and their children's In The early 1980s, research- cautiously because of the low numbers lives. ers found several ~clusters" of involved. It's sensible to focus on simple miscarriages among women Nevertheless, prudent avoidance would sug~ ways of reducing exposure to elec- who worked at video display ~est using a comforter or buying one of the tromagnefic fields rather than to terminals--also known as VI)Ts or computer low4~M F electric blankets now sold. Those make radical changes. M. Granger monitors. But while early, small-scale epi- blankets have heating elements that run in Morgan, a public-policy expert at demiologic studies seemed to show some con- closely spaced pairs, thereby reducing the Carnegie Mellon University. has pro- nection between VDT use and reproductive electromagnetic field (such blankets are la- posed a strategy he calls "prudent problems. larger and more careful studies beled as having reduced fields). In 1991. we avoidance," involving simple low-cost generally have not. Tested one low-field blanket. manufactured by or no-cost measures. Computer monitors do, however, produce Sunbeam-Home Comfort, and found that it Although prudent avoidance can intense magnetic fields of various low fre- did, indeed, produce a magnetic field one- be as easy as leaning back from a quencies. CIN sets produce comparable fields. twenlieth the strength of an old-style blanket's. computer screen. other methods of but viewers don't usually sit very close to a TV /' Cellular phones avoidin~ EMFs are more difficult-- set) The fields emanate from the two power- such as moving out of a house near a ful electromagnets that help produce images. After a Florida man went on power line. Whether such a move is The position of the magnets creates much national television in 1993 to prudent or paranoid depends largely stronger fields at the back and sides of a VDT blame his wife's fatal brain can- on one's own feelings about the than at the front. Although a monitor may cer on her cellular phone. nature of the risk. have a field of 60 mG at the side. most new manufacturers tried to quell public alarm by Some questions are too large to be models have a field of 2 mG or less an arm's insisting that ~thousands~ of research studies answered by individuals or families. length from the screen. Users can practice had proven the devices safe. Unfortunately, How much should a community "prudent avoidance~ by sittin~ at this distance. research has proven no such thing. spend to route transmission lines Offices can be designed to minimize workers' Cellular phones operate in the radio- away from a school? Should a high- exposure to the sides and backs of their neigh- frequency portion of the electromagnelic spec- voltage line be put on la]]er towers to bors' monitors. trum, between 800 and 900 megahertz-- minimize fields at ground level~ frequencies nearly lS million limes higher even though the expense will result Microwave ovels than the 60 hertz of household power. The in higher electricity rates? You might assume that elec- phones' antennas transmit to and receive from Such decisions belong in the polit- tromagnetic radiation from a network of antennas around the U.S. ical arena, since they involve either microwave ovens comes Intense radio-frequency radiation can heat the use of pub]ic funds or the control from the microwaves them- tissue: that's how microwave ovens work. But of electricity rates by state regulatory selves. Not so. As our own tests have repeat- the radio waves emitted by the phones are commissions. For example, the Ca]- edly demonstrated. microwave leakage from much weaker--about equivalent in energy to a ifomia Public Ulilities Commission ovens that are properly maintained and oper- flashlight bulb. The cellular carriers' antennas recently decided that, from now on, ated is minimal. operate at 100 watts, the same as a household ulilities can add as much as four per- Instead. the magnetic field surrounding an light bulb. Research on this type of radiation is cent to the cost of building a trans- oven comes from the electricity used to power scanty--even less definitive than research on mission line to reduce magnetic-field the appliance. The Electric Power Research household magnetic fields. exposure. In New Hampshire, the Institute measured 48,5 ovens and found that The worry about cellular phones has Souhe~an Valley School Board de- at a distance of not quite two feet, half of them cused on the portable type, which carries its cided to spend $100,000 to reduce generated a 60-Hz field of 10 mG or more. power supply and antenna in a single small fields from power fines passing by a Prudent avoidance simply involves not lin- handset. In such a phone, the radio waves new high school. ' gering near a microwave oven when it is in from the antenna are emitted from very near Once the debate is in the public operation, especially during long cooking the user's head. realm, there's a way for individuals times. At a distance of 46 inches, the median People who want to hedge their bets can or concerned groups to press their field of the tested ovens was down to 2.1 mG. simply choose not to use a portable cellular opinions. Residents along a propond phone, or they can limit the amount of time high-voltage transmission line might ~ Electric blankets spent using one. push for an extra-wide right-of-way or; ' Electric blankets bought Other options are a permanently installed for a slightly longer route that by- : more than about three car phone. with an antenna mounted outside passes populated areas. ' years ago expose users-- the car, or a semiportable model. A semi- - ~ff i2tili risk/:n~ikes you upset, fight 'all night, intermittently--to portable phone's antenna and power supply to change it,' advises Peter Sand- magnetic fields of 20 mG or more. Thafs are carried in a small tote bag; the handset man, a Boston-based psychologisl because an old blankefs heating elem ::t !s a emits no radio waves. V~naile operating the specializing in risk. "If you feel the large single loop of wire. phone, users can place the bag as far away utility is unresponsive, fight for a In a sludy published in 19911, David Savitz from them as the phone cord permits. more responsive one. · GONSUMEI~I~EPO~TS MAY 1994 359 MR. E. RTII. XV T!. R BY RUSSELL CLEMINGS fhe Iotest on whot to do obogt electromogneti¢ fields Elccrr,.ma~nctic lieIris so the debate conttnues- tEMFs) are everywhere--at "Most people who have your computer screen and looked at this body of evi- television, near your micro- deuce don't think it ~s con- wave, under your electric sistent. Not all studies show blanket. A by-product of an effect," says Leeka modern living, these invisi- Kheifets, epidemiologist for ble fields of weak radia- the utility indust~"s Electric lion--produced when elec- Power Research Institute. ~~ ~1~ ~ic~o~e, ~a~ge hood ~d lights all on, the meter read tricity flows through power Others are more cautious: ~ ~l~ 9.4. At work, I got a reading lines, wiring and appli- "~e utilities have been ve~' ances~have been a focus of fast to call things conflict- ~~ ~ of 1.6 at my desk. But a health concern since the [ate ing. I'm not sure I would be nearby copier produced 13.4 1970s. Yet after 15 years of so fast," says Louis Slesin, ~ f~ ~ milligauss, even in standby research, many questions editor of "Microwave News," mMe. remain about their health an authoritative newsletter. For lunch 1 went to my effects. More than 100 stud- ~at can we do? Should EMF exposure at low cost favorite Mexican restaurant. ies to date have found high we spend large amounts of (see the box below left). Out back were high-voltage rates of some cancers where money reducing our expo- Although opinions differ on lines atop huge steel towers. EMF exposures are believed sure, at the risk of wasting what constitutes a safe level On a table, the meter read to be heavy. And laborato%' our money? Or should we do of EMFs, many experts agree 1.6. But outside, by the lines, studies on human cells have nothing and hope for the that fields of 2 milligauss or it read 10.5. A few blocks found possibly harmful best? Some experts, includ- higher may be cause for con- away was a school where 16 chemical changes at some ing many in the utility cern. Still, EMFs are ~nvisi- employees had contracted exposure levels. So far, industry, suggest a middle hie. So how can you tell cancer. In his book The hi h? Great Power Line Ceverup, though, no one has been course, "prudent avoidance." where levels are g able to explain exactly how That means doing what Many suggest buying or Paul Brodeur blamed the such fields cause cancer, and you can to reduce your renting a gaussmeter, which schooi's cancers on EMFs can pinpoint high-exposure from the towering high-volt- sources in your environment. age lines. (in fact, Brodeur -*.~:5: ~.5~:~}~G '~~ g~{ Recently I borrowed a top- says that power lines are the of-the-line gaussmeter, the only EMF sources worth youcan easily reduce your exposure to EMFs from $2,000 Emdex II, and mea- worrying about--and that most household sources. The fields fade rapidl~ sured EMF levels in my warnings about EMFs from with distance, so step back from the microwave oven home, my neighborhood, my appliances are a utility when it is in use. Stay an arm's length from ~our corn- office and other places in my industry "smokescreen." puter screen, and switch off the monitor when ~ou city--with troubling results. "You don't hang out with don't need it. If you use an electric blanket, heat the Around the house, EMF lev- your hair drye( for eight ~d first, then turn off the blanket ~fore cmwl~g into els were generally low, less hours a day" he says. But bed. And try to spend as little time as possible near than 0.2 mllligauss--but in others aren't as sure.) major transmission and distribution line~the kind that front of my computer, the Retail prices for gau~me- hang from long, wine-bottle-size ins&tor~R.C. readin~ was 7.8. At the ters start at $100 and rental~ kitchen counter. with the C,~ngntted nnpdge 72 28 [,t ~N,,~FP',I'FY LX'F~E~ER