Electric Magnetic Fields in Environment

Electric and Magnetic fields in the Environment

Contents

Chief Executive Statement 3

How Electric and Magnetic Fields Work 4

EMF and your Health 9

The Findings of Scientific Review Bodies 16

ESB Policy 20

Glossary of Terms Used in this Booklet 21

Additional Suggested Reading 22

3

Electric and Magnetic �elds in the Environment

The possible health e�ects from electric andmagnetic �elds (EMF’s) associated with thetransmission, distribution and use ofelectricity have caused some level of publicconcern both in Ireland and internationally inrecent years. The main interest of mostpeople in this country has centred around the�elds produced by ESB power transmission lines, but questions have alsobeen asked about the �elds produced by other electrical sources such asappliances, distribution lines and substations.

ESB regards the protection of the health,safety and welfare of its sta�and the general public as a core company value.

In accordance with our desire to deal in an open manner with this issuewe are providing you with this information on the subject of electrical andmagnetic �elds. The quality of your living and working environment, alongwith the welfare of livestock and farm crops is of the utmost importance tous at all times.

All of the ESB networks comply with the most up to date internationalEMF guidelines and recommendations. Despite over 20 years of intensiveresearch into power frequency EMF’s, the international scienti�cconsensus is that there is no evidence to prove that these EMF’s cancause any harm.

We hope you �nd this booklet useful and informative and that it providesthe answers to the questions currently being asked on this issue, whichhas become a talking point during the 1990s.

To explain any technical terms used in the following pages, a glossary hasbeen included on page 21.

What is a field?

A field describes the influence ofan object on its surroundingspace. For example, atemperature field may existaround a hot object. Withinnature, a number of electric andmagnetic fields occur. The earthis itself an immense naturalmagnet with magnetic poles nearthe North and South Poles. (Fig.

1) This permitsthe use of acompass foraccurate directionfinding.Electricity is anaturalphenomenonwhich occurs aslightning and

within the human body as electricfields and currents which allowinformation to flow within cellsand tissues. Apart from thesenatural phenomena, electric andmagnetic fields are producedwherever electric power is in use.

In Ireland, electricity varies at apower frequency of 50Hz (i.e.alternating back and forth 50times each second) and producescharacteristic electric andmagnetic fields. At home andat work similar fields areproduced by wiring and byelectrical appliances ineveryday use.

What is an electric field?

An electric field is producedwithin the surrounding area whenvoltage is applied to a conductor(or wire). Just as the area arounda hot water pipe is affected by thetemperature of the pipe, the areasurrounding an electricalconductor is influenced by theconductor voltage. The strengthof an electric field at a givenlocation depends on two factors— the level of voltage applied tothe conductor and the distancefrom it.

The magnitude of an electric fieldis measured in volts (orthousands of volts – kilovolts) permetre. This is written as V/m orkV/m. (See calculation of electricfields, Figure 2).

The electric field to whichmembers of the public may beexposed from a power line isstrongest directly under the linewhere the conductors are nearestthe ground. This is usually nearthe middle of the span betweentwo adjacent support structures.By moving away from a powerline the strength of the electricalfield decreases rapidly.

4

How Electric and Magnetic Fields Work

Magnetic field around the earth

S

N

Fig. 1

The normal maximum electric fieldstrength at ground level 30m fromthe centre of the lines rangesfrom 0.08kV/m for a 110kV line to1.29kV/m for a 400kV line asshown in Table 1, Page 6.

For distribution lines (i.e. 38kVand below) field levels arecorrespondingly lower.

What is a magnetic field?

Magnetic fields are producedwhere electric current is present. The strength of a magnetic field ata given location depends on thelevel of current flowing in theconductor or wire and thedistance from it. Magnetic fieldsare normally expressed in termsof a quantity called the magneticflux density, expressed in terms oftesla (T). This relatively large unitis often expressed in submultiplessuch as microtesla (µT - onemillionth T). (See calculation ofmagnetic fields, Figure 3).

Magnetic fields produced bypower lines are strongest directlyunder the line where the

conductors are nearest theground.

Typical magnetic flux densities at30m from ESB transmission linesare shown in Table 1, Page 6 andrange from 0.2µT for a 110kV lineto 2.61µT for a 400kV line.

These levels are well below themagnetic field strength producedclose to many common electricalappliances, see page 10.

The difference between themagnetic fields produced bypower lines and electricalappliances is that the magnitudeof the fields produced byappliances falls off very rapidlywith distance. The fall off frompower lines is less rapid. Thefields from power lines tend to beconstant over time, while themagnetic fields produced byappliances only arise when theyare in use.

Electric and magnetic fields —photographs in this bookletshow typical values of electricand magnetic field strengthwhere electric power istransported or used.

5


r

I

Direction ofMagnetic Field

Magnetic Field in tesla = Constant (k) x Current (I)Distance (r)

Calculation of magnetic fields

E-+

Electric field (E) = Volts (V)metre (m)

V

m

Calculation of electric fields

Fig. 2

Fig. 3

6


These ‘profiles’ show the magnetic field near the ground for some typical overhead lines.

Mag

netic

Flu

x D

ensi

ty (

mic

ro T

esla

s)

Lateral Distance from Centre Line (metres)

12

10

8

6

4

2

0-50 0 50

400kV Single Circuit


220kV Double Circuit


110kV Double Circuit

38kV Single Circuit

Fig. 4

Type of line Electric Field Magnetic Strength Flux Density(kV/m) (µT)

38kV Single Circuit 0.012 0.13


110kV Double Circuit 0.043 0.1


220kV Double Circuit 0.219 0.41


ICNIRP Guideline 5 100(see page 19)

Table 1: Typical Electric Field Strength and Magnetic FluxDensity at 30 metres from ESB Overhead Lines.

ICNIRP Guideline 100µT

Fields within theelectromagnetic spectrum

There are many different sourcesof electric and magnetic fieldsand radiation. The Sun heats theEarth using electromagneticradiation, vision is possiblebecause of electromagneticradiation, watching television andlistening to radio are pastimesmade possible by moderntelecommunications and theingenious use of electromagneticfields. Not all these fields are thesame, they are distinguished bytheir frequency which ismeasured in cycles per second orHertz (Hz). (See electro-magneticspectrum page 8) At theextremely low frequency end ofthe electromagnetic spectrum wefind electric and magnetic fieldstypical of those associated withpower lines. Because these fieldsoperate at extremely lowfrequency, they contain very littleenergy and cannot directly breakapart molecules.

Because of the characteristics ofpower lines no electromagneticenergy radiates from the lines asa result of the surroundingelectric and magnetic fields.

Moving up the spectrum we passthrough radio, TV and microwavefrequencies into visible light.Further up, in the ultra-violetregion of the frequency spectrum,electromagnetic radiation

becomes ‘ionising radiation’.Ultra-violet light, X-rays andgamma rays are ionising radiationand have sufficient energy tobreak apart the molecules whichmake up genes. Excessiveexposure to these forms ofradiation is dangerous and canlead to cell mutations and cancer.

POWER lines used in Ireland

ESB uses high voltagetransmission and distribution linesto transmit electric power todemand centres throughout thecountry and low voltage lines toindividual houses. Overhead110kV lines have been used inIreland for almost 70 years, while220kV lines are in operation forabout 40 years. For the past 15years 400kV lines have also beenin use. Internationally, 220kVtransmission lines have beenwidely used since the 1920s.

7


Typical values directly underneath a 220kVtransmission line 4kV/m 8µT

8


Infra-Red

Very High Frequency

Very LowFrequency

Extremely Low

Frequency

Ultra-Violet

Visible Light

1022

1020

1018

1016

1014

1012

1010

108

106

104

100500

GammaRays

X - Rays

Cycles per secondHertz [Hz]

Electric Power

Ionising Radiation

Non -Ionising

Radiation

The Electromagnetic Spectrum

Investigations of EMF Effects

A debate about the possibleeffect on human and animal healthof electric and magnetic fields hascontinued since the 1970s. Sincethen, many thousands of studieshave been undertaken all over theworld to assess any potentiallyharmful effects from power lines,electrical appliances anddomestic wiring.

To date no conclusive evidencehas been found proving thatelectric and magnetic fields areharmful.

ESB is fully aware of thequestions currently being raisedand is actively supportingresearch programmes.

The following is a brief guide tothe body of research undertakenworldwide.

Human studies

Human volunteers haveassisted in internationalstudies. These detailedand thoroughprogrammes exposedvolunteers to electricand magnetic fieldsunder strictly controlledlaboratory conditions.The strengths employedwere much stronger

than people normally experiencein their day-to-day lives — rangingup to 20kV/m and 5,000µT, withexposures of several hours.These presented much greaterlevels of exposure than the levelsfrom ESB lines shown in Table 1,Page 6. Under these conditions, awide range of performance andblood tests were carried out.

No marked ill-effects of these veryhigh levels of exposure wereobserved. Small physiologicalchanges were seen, such aschanges in heart rate. But thesechanges were well within thenormal range of variation. Suchtemporary physiological changesare not regarded as adverse tohealth.

9

Electric and Magnetic Fields and Your Health

10


220kVTowerMeasured50m fromcentre line

ElectricblanketMeasuredas used

Hair dryerMeasuredat 30cm

TelevisionMeasuredat approx30cm

ElectricCookerMeasuredat 30cm

Electric fields aremeasured per metre (kV/m)

Magnetic fields aremeasured in microtesla (µT)

0 1 2

0.06kV/m

0.2 µT

2kV/m

3.3 µT

0.04kV/m

7 µT

0.01kV/m

4 µT

0 2 4 6 8 10

0.03kV/m

2 µT

Typical values of electric and magnetic fields in the environment

ELECTRIC FIELD

MAGNETIC FIELD

Epidemiological studies

Epidemiology is the study ofillness in large humanpopulations. It is used to obtainand test ideas about the origin ofillnesses as they relate to thecharacteristics and environmentof people.

Substantial epidemiologicalinvestigations relating to exposureor presumed exposure to power-frequency electric and magneticfields as a possible threat tohealth have been conducted andpublished in various parts of theworld. Such studies are statisticalin nature and require large samplepopulations. They have not beenundertaken in Ireland because ofthis country’s relatively smallpopulation.

Many external factors caninfluence an illness and it isgenerally not possible to makeallowance for all of these factors.Epidemiological study resultsattempt to indicate to what extentsome factor is statisticallyassociated with the occurrence ofan illness and can also indicatethe strength of this association.

Association does not, however,prove cause. To establish cause -particularly when the associationis relatively weak - scientistsgenerally require a consistency inresults between independently

conducted epidemiologicalstudies, a clear ‘dose/response’relationship (i.e. as the dose getsstronger the response getsbigger), supporting evidence fromanimal studies and preferably anunder-standing of the underlyingbiological mechanism.

Despite extensive scientificresearch none of theserequirements have been met inany substantive form to allow anydefinite conclusions be made inthe case of electric and magneticfields.

Most of the concern about powerlines and cancer stems fromearlier epidemiological studies ofpeople living near power lines.However, epidemiological studiescompleted in recent years showlittle evidence of a link betweenpower frequency fields andcancer.

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The US NATIONAL CANCERINSTITUTE STUDY

In 1997 the United StatesNational Cancer Institute (NCI)published one of the largestchildhood cancer epidemiologicalstudies to date. This studyexamined 638 children withchildhood leukaemia. Theconclusion of the study was “Ourresults provide little support forthe hypothesis that living inhomes with high time-weightedaverage magnetic field levels orin homes close to electricaltransmission or distribution linesis related to the risk of childhoodALL” (Acute LymphoblasticLeukaemia).

Animal studies

Through the use of animals incarefully monitored laboratoryconditions, it is possible toachieve good control of theexposure to electric and magneticfields. Such studies are veryvaluable in the investigation ofeffects on human health.However, difficulties remain indetermining the relevance ofthese studies to human exposure.Generally, animal studies haveconcentrated on the effects onthe nervous system. Again, theresults of such studies areinconsistent, showing widevariations. Some have reportedeffects, for example on behaviourand on the levels of certainhormones, such as melatonin(ahormone produced in the pinealgland of the brain), but withinconsistent results. No disease-causing effects have beenestablished.

Extensive studies have also beencarried out on farm animals inrelation to reproduction anddevelopment. No harmfulinfluences have been proven fromexposure to electric and magneticfields.

12


Typical values 0.3kV/m 60µT

CELL studies

Studies of cell and tissue culturesin the laboratory are oftendescribed as in-vitro (in glass),while the term in-vivo (in livestate) is applied to animal studies.In-vitro research studies onelectric and magnetic fields arenumerous and results have beenreported as producing bothpositive and negative results,making the overall picture bothcomplex and inconclusive. As anadded difficulty, it is not possibleto predict by merely observingcell cultures whether effects iffound will occur in animals orpeople. It is even more difficult toestablish whether effectsobserved at the cell level wouldhave any health implications. Thismatter is further complicated bythe presence in whole organismsof control and repair mechanismswhich are generally lacking in cellcultures and whose effect can notbe studied in individual cellstudies.

Certain reported effects appearto occur only within particularranges or ‘windows’ offrequency, time or field strength— although no specific windowshave yet been confirmed.However under these conditionshigher field exposures do notproduce a greater effect. It hasalso been shown that staticmagnetic fields comparable to the

earth’s have also been reportedto influence some cellexperiments.

Although individual scientificstudies mayappear to bevery convincing,it is important toremember thatsuch studiesonly become anaccepted partof science whenthey have beenreplicated inseverallaboratories andrelated tocurrent understanding.

Few of the many reported in-vitroeffects of extremely low-frequency fields have beenindependently replicated. There isagreement in the scientificcommunity that these fields donot cause cells to becomecancerous.

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A characteristic of agents such asionising radiation, which doinitiate cancer, is their ability toproduce changes in the geneticmaterial of the cell, either visibledamage to chromosomes orgenetic mutations.

Laboratory studies with electricand magnetic fields have notdemonstrated such health risks.

There has been some speculationthat electric or magnetic fieldsmight accelerate or promote thedevelopment of cancers in cellswhich are or have becomeotherwise predisposed to cancer.

Despite extensive scientificresearch this hypothesisedpromotion effect has not beenestablished.

Interaction mechanisms

Power-frequency electric andmagnetic fields are incapable ofdisrupting molecules by ionisationor of causing any significantheating in tissue.

The only established mechanismsof action by these fields is viainduced currents. Large inducedcurrents can, for example,stimulate nerve and muscle cells.The international guidelines inplace (see page 19) employ verylarge safety factors to ensure thatthese effects are not possible inindividuals exposed to EMF levelsat or significantly beyond theguideline levels.

Other research mainly centres onthe effects at the cell surface oron the transport of ions which canact as biochemical ‘messengers’across the cell membrane.

14


Typical everyday values 0.1kV/m 0.4µT

Several theoretical explanations ofmechanisms have been proposedand it seems that more than onemechanism may exist. But suchexplanations are speculative andno comprehensive theory hasbeen proposed which may beconfirmed by laboratoryexperiment.

One such theory which hasattracted widespread mediaattention is the HenshawHypothesis. In February 1996Professor Denis Henshaw, BristolUniversity published a paperproposing an attraction betweenradon gas and the electric fieldsurrounding high voltagetransmission lines. Thishypothesis was described asbeing “implausible” and “purelyspeculative” by the NRPB(National Radiological ProtectionInstitute, UK).

Scientific experiments todetermine the validity of thistheory by outdoor radon gasmeasurements under power lines,both in Ireland and the UK, foundno evidence to support thetheory.

15


Typical values 0.1kV/m 0.3µT

Independent international medicaland scientific bodies arecontinuing to review and monitorthe possibility of health effectsfrom exposure to extremely low-frequency electric and magneticfields. The findings of thesebodies carry considerable weight,as they reflect the judgments ofgroups of experts rather than theviews of individuals. This sectioncontains excerpts from theconclusions of two such bodies,along with some findings from anindependent national scientificreview by the Irish Government.

World Health Organisation(WHO) ‘Non-ionising RadiationProtection’

In 1989 the WHO published thesecond edition of its book ‘Non-ionising Radiation Protection’.The section on electric andmagnetic fields at extremely lowfrequencies concludes:

“Exposure to ELF electric andmagnetic fields does producebiological effects. However,except for fields strong enough toinduce current densities abovethe threshold for the stimulationof nerve tissues, there is noconsensus as to whether theseeffects constitute a hazard tohuman health. Human data fromepidemiological studies,including reported effects on

cancer promotion, congenitalmalformation, reproductiveperformance and general health,though somewhat suggestive ofadverse health effects, are notconclusive.”

In 1996 WHO began a five yearInternational EMF Project to re-examine all available literature andESB has made a financialcontribution towards this project.

US NATIONAL ACADEMY OFSCIENCES.

A major review of powerfrequency electric and magneticfield literature, and one of themost extensive to date waspublished in October 1996 by theUnited States National Academyof Sciences.

On its release Professor CharlesStevens, the chairman of theresearch committee, stated :

“Research has not shown anyconvincing way that EMF’scommon in homes can causehealth problems, and extensive

The Findings of Scientific Review Bodies

Typical values 0.3kV/m 1µT

16

laboratory tests have not shownthat EMF’s can damage the cellin a way that is harmful to humanhealth.”

The report concluded :

“No clear, convincing evidenceexists to show that residentialexposures to electric andmagnetic (EMF)are a threat tohuman health .....there is noconclusive evidence thatelectromagnetic fields play a rolein the development of cancer,reproductive and developmentabnormalities, or learning andbehavioural problems.”

DEPARTMENT OFENERGY(IRELAND)“Assessments of ScientificResearch on ElectromagneticFields’

Dr T. Mc Manus — ChiefTechnical Adviser, Department ofPublic Enterprises — hasprepared two extensiveassessments of scientificresearch on electromagneticfields. In his 1988 report to theMinister for Energy, he reportedamong his findings:

“An analysis of the situation leadsto the conclusion that there is nohealth risk on the basis ofpresent knowledge.”

In a 1992 report, Dr Mc Manussummarised the views of nationaland international organisations asfollows:

“Without exception these reportsand the position taken by theorganisations concerned do notsee enough evidence to be ableto indict electromagnetic fields asa hazard to health.”

US NATIONAL INSTITUTE OFENVIRONMENTAL HEALTHSCIENCES.

In June 1999, the NIEHSpublished their review of the EMFresearch conducted to date. ThisUS$60 million research andcommunication effort wasrequested by the United StatesCongress and was carried outover a six year period.

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The main conclusion of the reportwas that "The scientific evidencesuggesting that ELF-EMFexposures pose any health risk isweak." The report finds that someepidemiological studies haveshown a small increased risk butthat the mechanistic and animalstudies fail to demonstrate anyconsistent pattern.

"Epidemiological studies haveserious limitations in their abilityto demonstrate a cause andeffect relationship whereaslaboratory studies, by design, canclearly show that cause andeffect are possible. Virtually all ofthe laboratory evidence inanimals and humans and most ofthe mechanistic work done incells fail to support a causalrelationship between exposure toELF-EMF at environmental levelsand changes in biologicalfunction or disease status. Thelack of consistent, positivefindings in animal or mechanisticstudies weaken the belief thatthis association is actually due toELF-EMF, but it cannotcompletely discount theepidemiological findings."

SUMMARY OF STUDIES

The interpretation of the findingsof international and nationalreview bodies have one elementin common —no health risksfrom power-frequencyelectric andmagneticfields, at levelswhich peopleare exposed intheenvironmenthave beenestablished.

Epidemiological studiescompleted in recent years showlittle evidence of a link betweenpower frequency fields andcancer.

Laboratory studies have alsofailed to establish any mechanismwhereby low level electric and ormagnetic fields could cause anyform of ill health effect.

A connection between power lineEMF’s and cancer remainsbiophysically implausible.

ESB and national and overseasbodies are continuing to monitorand support researchdevelopments and to keep societyfully informed.


Typical values 0.1kV/m 0.3µT

18

International guidelines forExposure

Any guidelines for restricting theexposure of people to certainagents must rest on a solidscientific basis. The induction ofcurrents in the human body is theonly certain interaction of powerfrequency electric and magneticfields.

The World Health Organisation,in its 1987 Environmental HealthCriteria review of magnetic fields,stated that up to an inducedcurrent density of 10mA/m2 isacceptable. Naturally occurringcurrent densities within the body,caused for example by the actionof heart muscles, are also ofsimilar value.

International Commission onnon-ionising radiationprotection (icnirp)

In 1998 ICNIRP published itsmost recent guidelines forexposure to time varying electric,magnetic and electromagneticfields (up to 300GHz). Thecommission consists of aninternational panel of independenttop experts in electromagneticfields. The exposure guidelines inthe 1998 document were basedon avoiding known effects of highEMF levels on the body.

19


Typicalvalues0.1kV/m1.0µT

Typical values at 2 metres distance0.02kV/m 1µT

The following is a quotation fromthe 1998 guidelines:

“It is the view of the ICNIRP thatthe results from theepidemiological research on EMFexposure and cancer, includingchildhood leukaemia, is notstrong enough in the absence ofsupport from experimentalresearch to form a basis forsetting exposure guidelines.”

Based on the findings referred toabove, guidelines on exposurehave been prepared by theInternational Commission on Non-Ionising Radiation Protection. Forthe general public these are5kV/m and 100µT for electric andmagnetic fields respectively.

ESB’s commitment tosafeguard public health

ESB regards the protection of thehealth, safety and welfare of staffand the general public as a corecompany value.

Arising from concerns aboutpossible adverse health effectsresulting from exposure to electricand magnetic fields (EMF) fromelectrical equipment, such aspower lines and appliances, ESBhas decided to clearly state itspolicy in relation to this issue asfollows.

• Design and operate itsgeneration, transmission anddistribution networks inaccordance with the most up-to.date recommendations andguidelines of the various expertand independent internationalbodies.

• Closely monitor and supportengineering and scientificresearch in this area.

• Provide advice and informationto staff, customers and thegeneral public on this issue.

20


Typical values directly underneath a 10kVdistribution line 0.24kV/m 5µT

21

Glossary of Terms Used in this Booklet

Carcinogenic

Chromosomes

Current

Electric fields

Electricity

Epidemiology

Frequency

Induced current

Ionising radiation

Magnetic fields

Melatonin

Molecule

Power frequency

Radiation

Voltage

Causing cancer

The part of a cell involved with cell division and hereditarycharacteristics

The movement of an electrical charge analogous to therate of fluid flow in a pipeline

Invisible fields of force where voltage is present

A form of energy created by the flow of current or thepresence of voltage

A type of research that tries to find statistical linksbetween the occurrence of specific diseases andpeople’s exposure to possible causes

The number of repetitions of an electric wave per second

Current which flows in a body as a result of aninteraction with an electric or magnetic field

Radiation, such as X-rays, which has sufficient energy tobreak chemical and electrical bonds

Invisible fields of force found where electric current ispresent

A hormone produced in the pineal gland in the brain

The smallest particle of a substance that retains theproperties of that substance

The type of electric power that is used in Ireland, in 50Hertz (Hz)which current alternates back and forth 50times per second

Any of a variety of forms of energy propagated throughspace

The measure of potential strength of electricity. Voltagein a power line is analogous to pressure on a pipeline.

• World Health OrganisationEnvironmental health criteria 35. Extremely low frequency (ELF) fields. WHO 1984.

• World Health OrganisationEnvironmental health criteria 69. Magnetic fields. WHO 1987.

• World Health OrganisationFact Sheet WHO/205 November 1998Electromagnetic Fields and Public Health: Extremely low frequency (ELF)

• International Commission on Non-Ionising Radiation Protection,Guidelines for limiting exposure to time-varying electric, magnetic andelectromagnetic fields (up to 300GHz). Health Physics, Vol. 74, No. 4,April 1998.

• International Conference on Large High Voltage Electric Systems(CIGRE) Electric Power Transmission and the Environment: Fields, Noiseand Interference. Working Group 36.01 (Corona and Field Effects).

• Department of Energy Ireland. (Available from GovernmentPublications)- Electromagnetic Fields from High Voltage Transmission Lines, 1988.- Electromagnetic Fields, 1992.Author: Dr T. Mc Manus, Chief Technical Adviser.

• National Academy of Sciences, Possible health effects of exposure toresidential electric and magnetic fields,National Academy Press, 1996.

• National Cancer Institute, Residential exposure to magnetic fields andacute lymphoblastic leukaemia in children, Linet et al, The New England Journal of Medicine, Volume 337, Number 1, July 3 1997.

• National Radiological Protection Board (NRPB-UK) ElectromagneticFields and the Risk of Cancer.Vol. 3 No. 1 1992. Board Statement on Restrictions on Human Exposureto Static and Time-Varying Electromagnetic Fields and Radiation. Vol. 4No. 5 1993.

• Electromagnetic Fields and Human Health, Powerlines andCancer,Frequently Asked Questions,Dr.John E Moulder, Professor of Radiation Onocology,Medical College ofWisconsin.http://www.mcw.edu/gcrc/cop/powerlines-cancer-FAQ/toc.html

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Additional Suggested Reading

Electricity Supply Board,Lower Fitzwilliam Street, Dublin 2.Telephone: 01-676 5831 Fax: 01-661 5376 Telex: 93727 ESB EI

June 1999

The ESB hopes that this booklet has been informative and providesa greater understanding of the possible health risks associated withelectric and magnetic fields.

If you require further information please contact:

Printed on recycled paper

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Electric Magnetic Fields in Environment