health booklet 01.10:layout 1 · lead to tissue damage and possibly cancer. 3 the electromagnetic...

Health_booklet_01.10:Layout 1 6/10/08 14:44

ContentsWhat are radio signals?.......................................................... 3What are the biological effects and hazards? ...................... 4What do the experts say? ................................................... 4-5What are the international standards for exposure?........... 6How do mobile phones work?............................................... 6Illness Clusters ......................................................................... 7Mobile Phone Safety .............................................................. 8Handsfree kits and shields ..................................................... 9Children and radio signals ..................................................... 9FAQs and myths .................................................................... 10

Mobile phones and other wirelesstechnologies have become an integral partof everyday life. But does using a mobilephone regularly, or living near a base station,have any implications for our health?


What are radio signals?Radio signals are part of everyday life,emitted both by natural sources like thesun, the Earth and the ionosphere, andby artificial sources such as:

• mobile phone base stations

• broadcast towers

• radar facilities

• remote controls

• electrical and electronic equipment

Radio signals are a form of electromagneticenergy (or electromagnetic radiation - EMR),electric and magnetic fields movingtogether through space. Radio signals arenon-ionising, which means that they cannotdirectly impart enough energy to a moleculeto break or change chemical bonds. This isin contrast to ionising radiation, such as x-rays, which can strip electrons from atomsand molecules, producing changes that canlead to tissue damage and possibly cancer.

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The Electromagnetic Spectrum


What are thebiological effects andhealth hazards?A biological effect occurs when a changecan be measured in a biological system inresponse to a stimulus or change in theenvironment. However, a biological effectis not the same as a health hazard. Abiological effect only becomes a healthhazard when it damages the health of theindividual or of his or her children.

It has been known for many years thatexposure to sufficiently high levels ofradio signals can heat biological tissueand potentially cause tissue damage if thehuman body cannot cope with the extraheat. Studies have consistently shown thatthe radio signals routinely encountered bythe public are far below the levels neededto produce significant heating andincreased body temperature.

Much of the public concern relates to thepossibility of health hazards from long-term exposures at levels too low toproduce measurable heating. There havebeen studies reporting biological effectsbut not health hazards at low levels. Inmany cases, the studies have not beensubject to scientific peer review or theresults have not been independentlyconfirmed. The international consensus isthat current limits are based on all theavailable scientific evidence, incorporatelarge safety factors and are highlyprotective of health.

What do the experts say?

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“...the exposure to the generalpopulation that results fromtransmitters is very weak and onewould not expect such exposureto produce a health risk asdiscussed in the previous report.”Statens Strålskydd Institut (Sweden), 2008

“…there seems not to be a needto modify the present guidelinesto account for the risk of canceror other long-term adverseeffects not scientificallyestablished."International Commission on Non-Ionising

Radiation Protection (ICNIRP), 2007


ResearchOver the past 50 years, there has beenextensive research conducted into thepossible health effects of exposure tomany types of radio signals. As of July2008, there were over 1000 publicationson this topic in the World HealthOrganization (WHO) database.

Since 1995, more than 20 expert panelsand government agencies have examinedthe scientific evidence and their consensusis that there are no established healthhazards from exposures to radio signals atlevels below the 1998 guidelines of theInternational Commission on Non-IonisingRadiation Protection (ICNIRP). WHOrecommends adoption of the ICNIRPexposure guidelines.

However, the WHO has identified areasfor continuing research to support futurehealth risk assessments. Many researchprogrammes have been guided by theWHO research recommendations andthe WHO estimates that since 1997 overUS $200million of funding has beenallocated to such programmes.

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“...exposures to theradiofrequency energy producedby cellphones do not causehealth problems... Reviews ofall the research have not foundclear, consistent evidence ofany adverse effects."Ministry of Health, National Radiation Laboratory

(New Zealand), 2007

“The scientific evidence doesnot show a danger to users ofwireless phones, includingchildren and teenagers.”Food and Drug Administration, FDA (USA), 2003


What are theinternational exposurerecommendations?In 1998, the International Commission onNon-Ionizing Radiation Protection (ICNIRP),an independent scientific body recognisedfor its expertise by the WHO, issuedguidelines for radio signal exposure thatare applicable to mobile phones, basestations and other wireless devices.

The ICNIRP guidelines were developedfollowing reviews of the scientific literature,including thermal and non-thermal effects,and are designed to provide protectionagainst all established health hazards.The ICNIRP guidelines include substantialsafety factors. ICNIRP monitors newscientific findings to ensure that therecommendations are protective of health.

ICNIRP GuidelinesThe ICNIRP guidelines are recommendedby the WHO, the InternationalTelecommunications Union (ITU) and theEuropean Commission and have beenwidely adopted in Africa, Asia, Europeand the Middle East. Similar exposurestandards are used in the Americas. Due todifferences in scientific interpretation or inresponse to public concern some countriesapply more restrictive standards. Thesemeasures provide no additional healthprotection and may lead to increasedpublic concern.

How do mobilephones work?Mobile phone networks are divided intogeographic areas called cells, each of whichis served by a base station. To communicatewith each other, mobile phones and basestations exchange radio signals. The userconnects to the base station via the handsetand the system ensures that the connectionis maintained as the user moves from onecell to another.

When a mobile phone is switched on, itresponds to specific control signals fromnearby base stations. Once it has located asuitable base station the phone initiates anetwork connection. The phone remainsdormant, aside from occasional updates,until a call is made or received.

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What is a base station?What Transmitted power levels vary dependingon the geographical area of the cell,but the range is anything from less thana watt to 100 watts; lower for indoorbase stations.

At an outdoor site, one or more antennastransmit the radio signals. Each is typically15-30cm in width and 1-3 metres high,depending on the frequency of operation.The transmit pattern of the antennas isnarrow vertically, but broad horizontally,so that the radio signal level directlybeneath the antennas is very low. Typicallevels in publicly accessible areas are50 to 50,000 times below internationalsafety recommendations.

Illness ClustersThere has been speculation regardingalleged illness clusters (particularlycancer) near base stations. However,subsequent examinations by independenthealth authorities have not identified anytrue clusters linked with either proximityto the base stations or the low level radiosignals they transmit. Rare diseases areoften distributed randomly in thecommunity. Given the widespreadpresence of base stations there may bechance instances of apparent clusters asantenna sites need to be located wherepeople use phones.

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‘Considering the very low exposure levels and research results collected to date,there is no convincing scientific evidence that the weak RF signals from basestations and wireless networks cause adverse health effects.’WHO, May 2006

Base Stations: Beam shapes and directions


Mobile phonesCompliance of mobile phones is based onassessment of the Specific Absorption Rate(SAR), which is the unit of measurementfor the amount of RF energy absorbed bythe body. The SAR is determined at thehighest certified power level in laboratoryconditions, however, the actual SAR levelof the phone while operating can be wellbelow this value.

Mobile phones use adaptive power controlto reduce the transmitted power to theminimum possible whilst maintaining goodcall quality. This prolongs talk time andminimises interference to other callers. Forexample, during a voice call the averagepower output of a phone can vary from0.001 watt up to the maximum level whichis less than 1 watt. When coverage isgood, such as close to a base station, theoutput level may be similar to that of ahome cordless phone.

The view of the WHO is that theinternational exposure recommendationsare protective of all persons and that nospecial precautions are needed for mobilephone use. If individuals are concerned,they might choose to limit their exposureby limiting the length of calls, or using‘hands-free’ devices to keep mobilephones away from the head and body.Bluetooth earpieces use very low radiopowers and will also reduce exposure.

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Mobile phone shields Various products are being marketed thatclaim to increase the safety of mobilephone use. These products generally takethe form of shielded cases, earpiecepads/shields, antenna clips/caps, specialbatteries and absorbing buttons.

A mobile phone automatically operates onthe lowest power necessary to maintaincall quality. If an add-on device adverselyaffects the phone's antenna, the phonewill attempt to transmit more power up toits specified maximum.

Scientific evidence does not indicate anyneed for shields on mobile phones. Theycannot be justified on health groundsand the effectiveness of many suchdevices in reducing exposure is unproven.If individuals are concerned, personal"hands-free" devices have been shownto reduce exposures by at least a factor of10 by allowing the phone to be used awayfrom the head and body.

Children and radio signalsSome parents are concerned aboutwhether there are health risks for childrenusing mobile phones or where basestations are sited close to schools,day care centres or homes.

National authorities in some Europeancountries have recommendedprecautionary restrictions on phone use byyounger children due to concern aboutpossible greater vulnerability and to limitlonger lifetime exposures if there is anunrecognised health risk.

Health authorities in other countries, suchas Australia, the Netherlands, the USA andthe WHO have concluded that currentscientific evidence does not justify specificmeasures and that international safetyguidelines are protective of all persons,including children and pregnant women.

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FAQs & mythsI've read that mobile phones can causecancer. Is this true?There is no convincing scientific evidence that theuse of mobile phones can cause brain tumours orother cancers in humans. It is the consensus ofthe world wide scientific community that the lowpowered radio signals produced by a mobilephone do not have sufficient intrinsic energy toaffect genetic material.

What about other health risks?Independent scientific institutions around theworld review relevant research as it is published.The consensus of these expert groups is thatthere is no demonstrable evidence of a risk tohuman health from mobile phone radio signals.

How can we be sure that this research is accurate?Sophisticated and sensitive research methodsusing well-tried models for assessing health risksfrom other agents have been applied toinvestigate the safety of mobile phones. Manyresearch institutions and the guidelinesaccording to which such research is conducted,are controlled by government and independentbodies around the world. Research results arecontinually reviewed at an international level byorganisations such as the InternationalCommission on Non-Ionizing RadiationProtection (ICNIRP) and the World HealthOrganization (WHO).

I live close to a base station. Am I at risk?The consensus scientific view is that there areno health risks from living near a base station.Mobile phone base stations use low power radiotransmitters to reduce interference to nearbysites. Recent measurement surveys show thatexposures to base station radio signals rangefrom 0.002% to 2% of the levels ofinternational exposure guidelines, dependingon a variety of factors such as the proximity tothe antenna and the surrounding environment.This is lower or comparable to RF exposuresfrom radio or television broadcast transmitters.It is only in areas close to the antennas that therecommended limits may be exceeded and thenetwork operator prevents public access to theseareas by placing the antennas near the top ofthe mast or high on a building.

Why are there so many restrictions on usingmobile phones in hospitals?At short range, the radio signal from a mobilephone may cause interference with electronicmedical devices. At distances greater than 1-2m,the possibility is substantially reduced. It ispossible for mobile phones to be used indesignated areas of hospitals.

Why can't I use my mobile phone when I fly?It is standard practice on aircraft to turn off alltypes of radio transmitters and certain otherelectrical devices unless they have beendemonstrated not to cause interference toaircraft systems. There have been recentsuccessful trials of mobile phone use on aircraftin Europe and the USA, and plans forcommercial operations have been announced.


I've heard reports of mobile phones causingexplosions at petrol stations, is this true?There is no evidence of any established linkbetween radio signals from mobile phones orbase stations and petrol station fires. In fact, a2005 report for the Australian Transport SafetyBureau concluded that of 243 reported incidentsaround the world none was associated withtelecommunication equipment; instead, many ofthe fires were ignited by the discharge of staticelectricity from the human body.

How do we know that 3G and the othernew radio technologies are safe? There is a large body of existing scientificresearch at frequencies above and below thosefor 3G services, and a growing body of scienceusing these particular signals. Expert groups havenot established any signal specific effects, so thescientific consensus is that compliance withcurrent safety standards provides protectionagainst all known health effects.

Are some people more sensitive to radio signals?The WHO concluded in Fact Sheet No. 296 ofDecember 2005 that while self-reportedheadaches and other symptoms were real, therewas no scientific basis to link the symptoms toexposure to radio signals. Furthermore, the WHOsays that treatment should focus on medicalmanagement of the health symptoms and noton reducing exposure to radio signals.

I've read stories claiming that mobilephones can affect male fertility and spermquality, is this true? Some preliminary scientific studies have reporteda link, however, these studies have generally notproperly accounted for lifestyle factors, forexample, diet, smoking, etc. The consensus viewof expert public health bodies, including theWHO, is that there are no adverse health effectsassociated with the radio signals used by mobilephones or base stations.

Should I be concerned about the wirelessnetwork in my office or at my child'sschool?The UK Health Protection Agency advises that onthe basis of current scientific information Wi-Fiequipment satisfies international guidelines and,therefore, there is no reason why schools andothers should not use Wi-Fi equipment. Inaddition, the WHO concluded in May 2006 that'...there is no convincing scientific evidence thatthe weak RF signals from base stations andwireless networks cause adverse health effects.'

Are the stories that mobile phones can cookeggs or make popcorn pop really myths?They are both myths. There is simply not enoughpower from a mobile phone to produce eithereffect. A mobile phone has a maximum averagepower of about 0.25 watts, compared to 900watts or more from a microwave oven.

Does a lower SAR mean that a phone is safer?No. Variations in SAR do not mean that thereare variations in safety. While there may bedifferences in SAR levels among phone models,all mobile phones must meet RF exposureguidelines.

Where can I get the SAR value for my phone?SAR information for many phones is nowincluded with the instructions as well as beingpublished on the company website.

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Key reference sites for mobile phones and healthWorld Health Organization (WHO)www.who.int/emf

European Commission Health-EU Portalec.europa.eu/health-eu

U.S Food and Drug Administration andFederal Communications Commission CellPhone Factswww.fda.gov/cellphones/

U.K. Health Protection Agencywww.hpa.org.uk/radiation/

International Commission on Non-IonizingRadiation Protectionwww.icnirp.de/

Produced by the GSM Association October 2008www.gsmworld.com/health


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