Upload
others
View
6
Download
0
Embed Size (px)
Citation preview
MacDonald, Cecilia BCUC:EX
From: Daria Zovi [[email protected]]
Sent: Friday, June 03, 2005 3:22 PM
To: Commission Secretary BCUC:EX
Subject: 2005 TSCP application information request #2
Page 1 of 1
6/6/2005
Hello Mr. Pellatt, Please accept IRAHVOL information request #2 for British Columbia Transmission Corporation - 2005 Transmission System Capital Plan (document IRAHVOLIR#20304.pdf) and 7 attachments. Thank you Daria Zovi Daria Zovi IRAHVOL Steering Committee 164 Norton Rd. Salt Spring BC V8K 2P5 CANADA ph/fax (250) 537-1429 e-mail:[email protected]
C2-3
BCTC – 2005 Transmission system Capital Plan F2006 to F2015
IRAHVOL Information request #2, June 3, 2005 1. Evaluation of HVDC Light Alternative Transgrid Solutions evaluation of HVDC Light assumes that the maximum HVDC Light rating available is 330 MW, hence two complete systems would be required to reach the desired capacity per stage of 600 MW. Although 330 MW is the highest capacity installed to date, ABB information provided to IRAHVOL on May 18th, 2005 (It is time to connect, attached) describes ratings of 550MW with 150kV modules M6, and ratings of 720MW and 1100MW with 300kV modules M8 and M9. 1.1 Please provide an evaluation of HVDC Light technology based on these
ratings and project requirements for both phase 1 and phase 2, including the possibility of advancing phase 2 to supply 1100MW using 300kV Modules M9 in phase 1.
1.2 Please describe technical differences between 330MW ratings installed to
date and 550MW, 720MW and 1100MW ratings. 1.3 Please describe ABB guarantee for turn-key installations at above ratings. 1.4 Please describe services and products supplied by ABB. HVDC Light appears to be able to provide power control for normal optimal dispatch to optimize the loading on parallel paths and avoid overload of the cables following contingencies. We assume BCTC plans to do this with AC cables by using series connected phase angle regulators. 1.5 Please provide an evaluation of HVDC Light alternative versus AC alternative in this respect. For network security BCTC may not allow local generation to go off-line, and pay a premium for VI generation for reliability purposes. It appears that HVDC Light technology may be able to achieve secure operation without the need for sub-optimal generation dispatch. While it is true that AC cables would strengthen the AC network as well, something might need to be done to regulate the voltage on the south end of the island due to the excess charging current from the AC cables. This appears not to be a problem with HVDC Light since it can regulate the voltage.
HVDC Light appears to be able to provide voltage support on the Mainland and Vancouver Island. Reactive power support from the converter terminals, within the MVA rating of the converters, can increase overall transfer capability when remote from generation (or during periods when local generation is off-line). Dr. Rashwan attempts to discount this advantage on two fronts. First, he states that the capability is limited to within the MVA rating of the converter. This is just like the voltage support available from a generator. If the DC power is backed off by 10 - 20 % with the balance flowing on the 500 kV AC cables the reactive power available from the converters for dynamic voltage support is significant and useful. Second, he states that the AC system is strong at both ends therefore the reactive power available from the terminal is insignificant since the voltage is well-regulated presumably from generation. On the one hand he says the voltage support capability of the DC is relatively insignificant, while on the other hand he states that shunt compensation and synchronous condensers are used for voltage support.
1.6 Please provide an evaluation of the HVDC Light alternative versus AC alternative including capital, operating, and environmental costs of voltage support measures proposed and/or already existing on the Mainland and Vancouver Island. 2. Criteria for evaluation 2.1 Since HVDC Light technology appears to have many advantages over the AC alternative in terms of environmental, aesthetic, and social and economic impacts, please provide a multiple account evaluation to compare not only the initial costs but also all other costs, including environmental and socio-economic costs of HVDC Light and AC alternatives. In particular, provide a qualitative and, wherever possible, quantitative evaluation of the two technologies on the basis of: 2.2 types and levels of electromagnetic fields (EMF) generated 2.3 visual impacts of the land portions of the installations 2.4 safety of the land portions of the installations (fire risk, injuries, inductive currents) 2.5 environmental impacts of sea cables (fluid leakage, footprint, EMF)
2.5.1 Please provide the schedule and amount of insulating alkylbenzene fluid added to existing 138kV AC cables since installation for operational purposes and due to leakage. 2.6 economic impacts due to public perception of EMF generated (property devaluation, loss of business –daycares, campgrounds) 2.7 possible increase of the cost of the project due to public opposition and/or legal action based on the potential and/or perceived health risk associated with EMF generated. 2.7.1. Please state the estimated cost penalty to be added to the capital cost of the project as a result of BCTC’s decision to not recommend constructions of overhead lines on the existing right of way in Tsawwassen. 3 Clarifications of TSCP Application IR#1 Question 1 1.1. refers to the attached World Health Organization fact sheet 263. The same definition of ICNIRP exposure guidelines appears in the ICNIRP statement, Use of Guidelines (excerpt attached). Canada currently does not have guidelines for long-term exposure to EMF, however Switzerland and Sweden amongst other countries and states have guidelines in regards to new installations that are aimed at minimizing human long-term EMF exposure on the basis of potential health risks (attached). In Canada the Federal-Provincial-Territorial Radiation Protection Committee issued a statement on the issue of Power-Frequency Magnetic Fields and Childhood Leukemia (attached) in which it states “The outcome of a recently conducted pooled analysis of several epidemiological studies shows a two-fold increase in the risk of leukemia in children living in homes, where the average magnetic field levels are greater than 0.4 microtesla (4 milligauss). However it continues, “epidemiological evidence to date is not strong enough to justify a conclusion that EMFs in Canadian homes, regardless of locations from power lines, cause leukemia in children”. The findings do not put an end to doubt or question. 3.1 Do you know that long-term exposure to extremely low frequency EMF above 2 milligauss is safe? 3.2.If we do not know whether or not EMF cause childhood leukemia or other diseases do you think that with cost effective alternatives the option which eliminates risk should be chosen?
3.3 Please provide spot measurements of EMF levels on Salt Spring under the existing 138kV Ac overhead lines and at different distances nearby. 3.4 Please provide spot measurements of EMF levels in proximity to existing installations in British Columbia of double circuits 138kV running at capacity and 230kV transmission lines. 3.4 Please provide a history of the power carried along the existing 138kV circuits through Salt Spring Island for the last 10 years. 4. Routing alternatives The objectives of the project as described on page iv of the Project Description (prepared by BC Hydro Engineering, Jan 2005) are: 1. to provide system reliability on VI 2. to meet current and future electricity demand on VI 3. to reduce on going operating and maintenance costs 4. to reduce environmental impacts resulting from cable failures and
maintenance activities 5. to decrease exposure to system failures due to seismic events These objectives as well as the needs of the stakeholder groups and the objectives of the regulatory agencies involved do not appear to be all satisfactorily addressed with the current proposal. Alternative solutions may be: A.Generation on Vancouver Island based on the use of renewable resources B. Use of HVDC Light technology for a transmission link along the existing right of way between Arnott and VIT terminals C. Use of AC or HVDC Light technology for a transmission link along an alternative route between Arnott and VIT D. Use of AC or HVDC Light technology for a transmission link along alternative route between a terminal on Vancouver Island and a terminal elsewhere 4.1 Please provide digital bathimetric data of the existing right of way between Arnott and VIT terminals. 4.2 Please provide digital bathimetric data of possible alternative route from Arnott to VIT via Porlier Pass and Samson Narrows along an all submarine route through the Gulf Islands and landing at Crofton substation.
4.3 Please provide digital bathimetric data of possible alternative route from Arnott to VIT via new land right of way across Galiano Island below Porlier Pass, south of Secretary Island, North of Salt Spring Island, through Houston Passage landing at Crofton substation. 4.4 Please provide digital bathimetric data of possible alternative route from Arnott to Pike terminals along an all submarine route through the Gulf Islands. 4.5 Please provide digital bathimetric data of possible alternative route from Cypress to VIT terminals via new land right of way across Galiano Island below Porlier Pass, south of Secretary Island, North of Salt Spring Island, through Houston Passage landing at Crofton substation. 4.6 Please provide an evaluation of how the objectives of VITRP may be addressed by an HVDC Light transmission link between CCB and DMR terminals. 4.7 Please provide an evaluation of how the objectives of VITRP may be addressed by an HVDC Light transmission link between VI and the Olympic Peninsula. 4.8 Would BCTC be able to export and/or import power to and from the US via the proposed VITRP and the proposed Juan de Fuca interconnector? 4.9 For the portion of the project relative to power supply to Southern Gulf Islands, please provide a multiple account evaluation to compare not only the initial capital costs but also all other maintenance and operation, environmental and socio-economic costs of alternative supply from Vancouver Island versus proposed 230KV AC system. 5. Public participation In its public planning informational material (copy attached) BCTC states “it is committed to an open and transparent process that ensures stakeholders are informed and actively involved in discussions about major transmission initiatives in British Columbia”. 5.1 Please provide the date of the commencement of planning activities for the increased supply to Vancouver Island via a new transmission link. 5.2 Please provide the date of BCTC notification of the Vancouver Island Transmission Reinforcement Project to Gulf Island residents and local governments.
5.3 Please provide copies of requests for meetings from IRAHVOL and Gulf Islands local governments and a list of public meetings held since initial notification. 5.4. Please provide a schedule for public planning for VITRP from notification to Gulf Island residents to submission of CPCN application.
Event list
SLD for a typical HVDC Light station
WHO | Electromagnetic fields and public health: extremely low frequency fields and cancer
All WHO
This site only
Home
About WHO
Countries
Health topics
Publications
Research tools
WHO sites
Media centre
News
Events
Fact sheets
Multimedia
Contacts
Media centre
WHO > WHO sites > Media centre > Fact sheets
printable version
Fact sheet N°263October 2001
Electromagnetic fields and public health: extremely low frequency fields and cancer
Electromagnetic fields and public health: extremely low frequencyFull text
In 1996, the World Health Organization (WHO) established the International Electromagnetic Fields (EMF) Project to address the health issues associated with exposure to EMF. The EMF Project is currently reviewing research results and conducting risk assessments of exposure to static and extremely low frequency (ELF) electric and magnetic fields. WHO plans to conduct an evaluation of all health effects from ELF field exposure in 2002-3.
Whenever electricity is conducted through transmission lines, distribution lines or is used in appliances, both electric and magnetic fields exist close to the lines or appliances. The power frequency used is 50 or 60 Hz. Use of electric power has become part of everyday life. However, questions have been raised as to whether these and other ELF fields are carcinogenic.
The International Agency for Research on Cancer (IARC) -- a specialized cancer research agency of WHO -- has recently concluded the first step in WHO's health risk assessment process by classifying ELF fields with respect to the strength-of-the-evidence that they could cause cancer in humans.
This Fact Sheet updates findings of recent reviews on the health effects of static and ELF electric and magnetic fields conducted by IARC (June 2001), by the Health Council of the Netherlands (May 2001), and by an expert Advisory Group of the National Radiological Protection Board in the United Kingdom (AGNIR) (March 2001).
IARC evaluation
In June 2001, an expert scientific working group of IARC reviewed studies related to the carcinogenicity of static and ELF electric and magnetic fields. Using the standard IARC classification that weighs human, animal and laboratory evidence, ELF magnetic fields were classified as possibly carcinogenic to humans based on epidemiological studies of childhood leukaemia. Evidence for all other cancers in children and adults, as well as other types of exposures (i.e. static fields and ELF electric fields) was considered not classifiable either due to insufficient or inconsistent scientific information.
"Possibly carcinogenic to humans" is a classification used to denote an agent for which there is limited evidence of carcinogenicity in humans and less than sufficient evidence for carcinogenicity in experimental animals.
http://www.who.int/mediacentre/factsheets/fs263/en/ (1 of 4) [27.May.05 10:01:19 AM]
WHO | Electromagnetic fields and public health: extremely low frequency fields and cancer
This classification is the weakest of three categories ("is carcinogenic to humans", "probably carcinogenic to humans" and "possibly carcinogenic to humans") used by IARC to classify potential carcinogens based on published scientific evidence. Some examples of well-known agents that have been classified by IARC are listed below:
Classification Examples of agents
Carcinogenic to humans Asbestos
(usually based on strong evidence of carcinogenicity in humans) Mustard gas
Tobacco (smoked and smokeless)
Gamma radiation
Probably carcinogenic to humans Diesel engine exhaust
(usually based on strong evidence of carcinogenicity in animals) Sun lamps
UV radiation
Formaldehyde
Possibly carcinogenic to humans Coffee
(usually based on evidence in humans which is considered credible, but for which other explanations could not be ruled out)
Styrene
Gasoline engine exhaust
Welding fumes
ELF magnetic fields
Do ELF fields cause cancer?
ELF fields are known to interact with tissues by inducing electric fields and currents in them. This is the only established mechanism of action of these fields. However, the electric currents induced by ELF fields commonly found in our environment are normally much lower than the strongest electric currents naturally occurring in the body such as those that control the beating of the heart.
Since 1979 when epidemiological studies first raised a concern about exposures to power line frequency magnetic fields and childhood cancer, a large number of studies have been conducted to determine if measured ELF exposure can influence cancer development, especially leukaemia in children.
There is no consistent evidence that exposure to ELF fields experienced in our living environment causes direct damage to biological molecules, including DNA. Since it seems unlikely that ELF fields could initiate cancer, a large number of investigations have been conducted to determine if ELF exposure can influence cancer promotion or co-promotion. Results from animal studies conducted so far suggest that ELF fields do not initiate or promote cancer.
However, two recent pooled analyses of epidemiological studies provide insight into the epidemiological evidence that played a pivotal role in the IARC evaluation. These studies suggest that, in a population exposed to average magnetic fields in excess of 0.3 to 0.4 •T, twice as many children might develop leukaemia compared to a population with lower exposures. In spite of the large number data base, some uncertainty remains as to whether magnetic field exposure or some other factor(s) might have accounted for the increased leukaemia incidence.
Childhood leukaemia is a rare disease with 4 out of 100,000 children between the age of 0 to 14
http://www.who.int/mediacentre/factsheets/fs263/en/ (2 of 4) [27.May.05 10:01:19 AM]
WHO | Electromagnetic fields and public health: extremely low frequency fields and cancer
diagnosed every year. Also average magnetic field exposures above 0.3 or 0.4 •T in residences are rare. It can be estimated from the epidemiological study results that less than 1% of populations using 240 volt power supplies are exposed to these levels, although this may be higher in countries using 120 volt supplies.
The IARC review addresses the issue of whether it is feasible that ELF-EMF pose a cancer risk. The next step in the process is to estimate the likelihood of cancers in the general population from the usual exposures and to evaluate evidence for other (non-cancer) diseases. This part of the risk assessment should be finished by WHO in the next 18 months.
International guidelines
International guidelines on exposure limits for all EMF have been developed by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) - a non-governmental organization (NGO) in official relations with WHO and a partner in WHO's International EMF Project. While the ICNIRP guidelines for EMF exposure are based on comprehensive reviews of all the science, the limits are intended to prevent health effects related to short-term acute exposure. This is because ICNIRP considers the scientific information on potential carcinogenicity of ELF fields insufficient for establishing quantitative limits on exposure.
Some national responses
Regulatory policies for agents classified as possible carcinogens vary by country and by particular agent. The carcinogenic evaluation and classification of an agent by IARC does not automatically trigger a national regulatory response. While gasoline exhaust and coffee have been classified as possible human carcinogens, there has been a significant response by government to reduce gasoline engine exhausts, but there has not been any effort to limit intake of coffee.
In response to increasing public concern over health effects from EMF exposure, several countries have established their own scientific reviews prior to the IARC evaluation. Already in 1998, a working group examining the issue for the US National Institute of Environmental Health Sciences (NIEHS) classified ELF magnetic fields as possibly carcinogenic to humans. The US government agency has since recommended "passive regulatory action", described as continued information and education of the public and encouraging power utilities to voluntarily reduce exposure to people where possible.
In the United Kingdom, an Advisory Group on Non-Ionising Radiation recently reported to the National Radiological Protection Board (NRPB) on the topic of power frequency EMF and the risk of cancer (AGNIR, 2001). It concluded that while the evidence is currently not strong enough to justify a firm conclusion that EMF fields cause leukaemia in children, the possibility remains that intense and prolonged exposures to magnetic fields can increase the risk of leukaemia in children. Further, they provided research recommendations. The Health Council of the Netherlands, a major scientific advisory body of the Netherlands government, reached similar conclusions.
WHO's response
While the classification of ELF magnetic fields as possibly carcinogenic to humans has been made, it remains possible that there are other explanations for the observed association between exposure to ELF magnetic fields and childhood leukaemia. In particular, issues of selection bias in the epidemiological studies and exposure to other field types deserve to be rigorously examined and will likely require new studies. WHO therefore recommends a follow-up, focused research programme to provide more definitive information. Some of these studies are currently being undertaken and results are expected over the next 2-3 years.
WHO's EMF Project aims to help national authorities balance the benefits of electrical technology against possible health risks, and to help them decide what protective measures may be needed. It is especially difficult to suggest protective measures for ELF fields because we do not know what field characteristic might be involved in the development of childhood leukaemia and therefore need to be reduced, or even if it is the ELF magnetic fields that are responsible for this effect. One approach is to have voluntary policies that aim to cost-effectively reduce exposure to ELF fields. This has been discussed in the WHO Backgrounder issued March 2000.
Some precautionary measures are outlined below:
Further reading
http://www.who.int/mediacentre/factsheets/fs263/en/ (3 of 4) [27.May.05 10:01:19 AM]
WHO | Electromagnetic fields and public health: extremely low frequency fields and cancer
● Government and industry: These entities should be cognisant of the latest scientific developments and should provide the public with balanced, clear and comprehensive information on potential EMF risks, as well as suggestions for safe and low cost ways to reduce exposures. They should also promote research that will lead to better information from which assessments of health risk can be made.
● Individuals: Members of the general public might choose to reduce their EMF exposure by minimizing the use of certain electrical appliances or by increasing distance to the sources that can produce relatively high fields.
● Consultation with local authorities, industry and the public when siting new power lines: Obviously power lines must be sited to provide power to consumers. Siting decisions are often required to take into account aesthetics and public sensibilities. However, siting decisions should also consider ways to reduce peoples' exposure.
● An effective system of health information and communication among scientists, governments, industry and the public is needed to help raise general awareness of programmes to deal with exposure to ELF fields and reduce any mistrust and fears.
● AGNIR (2001) Advisory Group on Non-Ionising Radiation, Power Frequency Electromagnetic Fields and the Risk of Cancer. National Radiological Protection Board (UK) 2001.
● Health Council of the Netherlands (2001). Electromagnetic fields: Annual Update 2001.● ICNIRP (1998) International Commission on Non-Ionizing Radiation Protection Guidelines for
limiting exposure to time varying electric, magnetic and electromagnetic fields (up to 300 GHz). Health Physics 74(4), 494-522.
● Portier CJ and Wolfe MS (eds.), National Institute of Environmental Health Sciences of the National Institute of Health. Assessment of health effects from exposure to power-line frequency electric and magnetic fields. NIEHS Working Group Report, Research Triangle Park, NC, USA, NIH Publication No. 98-3981, 1998.
● Repacholi M and Greenebaum B (eds.), Interaction of static and extremely low frequency electric and magnetic fields with living systems: health effects and research needs. Bioelectromagnetics 1999; 20: 133-160.
● WHO Backgrounder on Cautionary Policies, March 2000
RELATED LINKS
- The International Electromagnetic Fields Project
- Electromagnetic fields
For more information contact:
WHO Media centre Telephone: +41 22 791 2222 E-mail: [email protected]
Employment | Other UN Sites | Search | Suggestions | RSS | Privacy
© World Health Organization 2005. All rights reserved
http://www.who.int/mediacentre/factsheets/fs263/en/ (4 of 4) [27.May.05 10:01:19 AM]
Federal-Provincial-Territorial Radiation Protection Committee – Canada
Response Statement to the Issue of Power-Frequency Magnetic Fields and
Childhood Leukemia – Issued on January 20, 2005
The Federal-Provincial-Territorial Radiation Protection Committee (FPTRPC) is
aware of concerns about possible health risks from exposure to power frequency
electric and magnetic fields (EMFs). In response, the FPTRPC developed a
Position Statement to address the issue*. Of particular interest is the risk of cancer
from living near power lines and other sources of EMFs. These concerns appear to
arise as a result of the controversial and contradictory findings in scientific
research, especially from epidemiological studies.
The outcome of a recently conducted pooled analysis of several epidemiological
studies shows a two-fold increase in the risk of leukemia in children living in
homes, where the average magnetic field levels are greater than 0.4 microtesla (4
milligauss)†. The explanation for this elevated risk estimate is unknown, but the
authors of the pooled analysis suggest that it may be accounted for, in part, by
selection bias of cases and controls in the original studies used for the pooled
analysis. However, the number of subjects in the greater-than-4-milligauss group
is very small, and thus the significance of the finding is questionable. More refined
statistical and epidemiological methods will be needed to clarify this finding.
Further, no mechanism has been identified in the research literature that supports
the suggestion that these fields can cause or promote the development of cancer.
It is the opinion of FPTRPC that the epidemiological evidence to date is not strong
enough to justify a conclusion that EMFs in Canadian homes, regardless of
locations from power lines, cause leukemia in children.
* Position Statement for the General Public on the Health Effects of Power-
frequency (60 Hz) Electric and Magnetic Fields; issued by the Federal Provincial
Territorial Radiation Protection Committee – January 20, 2005
†Ahlbom A, Day N, Feychting M, Roman E, Skinner J, Dockerty J, Linet M,
McBride M, Michaelis J, Olsen JH, Tynes T and Verkasalo PK. A pooled analysis
of magnetic fields and childhood leukaemia. Br J Cancer. 2000;83(5):692-698.
Magnetic fields... A NEW GUIDE POR DECISIONS ON LOW-PREQUENCY ELECTRIC AND MAGNETIC
PIELDS HASED ON UNCERTAIN HEALTH EHECTS
CONTENTS 2/1996
NEW PRESIDENT OP NSRP
Asker Aarkrog has been appointed new president
of the Nordic Society for Radiation Protection.
PROTECTING THE ENVIRONMENT
Radiation protection of nature - impressions
from an international symposium in Stockholm.
8
The Swedish Radiation Protection Institute, the National Board of Occupational Safety
and Health, the National Board of Housing, Building and Planning, the National
Electrical Safety Board, and the National Board of Health and Welfare, have jointly
published a booklet on their common policies and recommendations on low-frequency
electric and magnetic fields. The booklet is based on available scientific findings and
presents technical and economic aspects of possible countermeasures in the light of
limited community resources. The national authorities recommend a precautionary
principle primarily based on non-discountable cancer risks. No limit values ate specified.
The publication is intended for use as support in decision-making where different aspects
must be weighted in each individual case, balancing possible hazards against technical
and economic considerations.
5
HEMANGIOMA INPANTS
New research on the hemangioma infants
is published and discussed by Lundell, Holm
ami Lindell. Thyroid cancer has been
observed but no excess leukemia risk.
Uncertain Results from Epidemiological Studies
A large number of epidemiological studies are being performed in order to
establish whether there may be a connection between exposure to electric or
magnetic fields and an elevated risk of cancer. Where exposures in the
working environment are concerned, the main focus of attention has been on
the risks of certain forms of leukemia and brain tumour. For exposure in the
dwelling environment, the main concern has been with leukemia risks to
children. The results contain many points of uncertainty. For example,
different scientific reports indicate excess risks for completely different kinds
of cancer. Furthermore, there are no convincing and acceptable connections
between dose and the magnitude of risk. Experimental studies have so
10
THE CASE OP LINEARITY
The debate goes on with a letter from
Dr Rossi and Dr Webster and a
response from Bo Lindell.
13
continued on page z
far not yielded any results that clearly corroborate the epidemiological findings.
Several groups of experts have all come to the conclusion that exposure to low-
frequency magnetic fields cannot be convincingly shown to entail elevated risks of
cancer but that certain epidemiological studies provide some cause for suspecting
that there may be a connection with particular forms of cancer e.g. childhood
leukaemia.
The Precautionary Principle in Perspective
The debate regarding the health effects of work with computer displays (VDTs)
escalated during the first part of the 1980s and culminated in 1986-88. Despite
identified ergonomic problems, tbe discussion focused heavily on electric and
magnetic fields. SSI took the position that although mandatory regulations were
impossible, voluntary actions based on some principles of caution were highly
desirable. SSI laboratories took a leading position in the development of
instruments, test methods and standards. The response from both users and
manufacturers was immediate and overwhelmingly positive. The VDTs of today,
about ten years afterwards, have electric and magnetic field emissions which are
10-100 times lower than those of the 1980s without the regulating authorities
having issued any regulations and without any substantial increase in cost.
In the USA, researchers at Carnegie Mellon University, Pittsburg, have
formulated an approach to magnetic field problems which they have termed
"prudent avoidance". They argue that, as long as our knowledge of the connection
between health hazards and exposure remains incomplete, society cannot resort to
expensive, peremptory measures. On the other hand, given the reasonably strong
suspicion of detrimental effects to health, one should still take steps which do not
in themselves entail heavy expenditure or any other inconvenience. A similar
approach has been advocated, for example, in the preparatory work to the
Radiation Protection Act and the Health Protection Act. Already in 1993, the
Swedish Radiation Protection Institute published a policy document (I) on
magnetic fields along these lines. This was followed by an information brochure
intended for the public as a first result of an inter-authority collaboration.
Lars-Erik Paulsson,
Principal Scientist at the
Division of Non-ionising
Radiation at SS/.
published by:
SWEDISH RADIATION
PROTECTION INSTITUTE.
address:
SWEDISH RADI ATION
PROTECTION INSTITUTE (SSI)
S-Ill l6 STOCKHOLM
SWEDEN
TELEPHONE: +468 7297lOO.
TELEFAX: +468 7297I08.
editorial board:
LARS-ERIK HOLM, DIRECTOR-GENERAL
JOOST IlAYARDS, HEAD OF INFORMATION OFFICE AND
RESPONSIHLE IN ACCORDANCE WITH SWEDISH LAW.
LARS PERSSON, EDITOR [[email protected]]
IIJORN HOLM, EDITOR [[email protected]]
art director.
Criteria Group
There is a long tradition in Sweden of issuing mandatory regulations for identified
risk factors with regard to the occupational environment. The basis for these
regulations is developed by "Criteria Groups" established by the National Institute
of Working Life (formerly National Institute of Work, Environment and Health).
SSI has actively taken part in the group for physical risk factors. In 1995, a
working group presented a comprehensive report (2) on an evaluation of all the
epidemiological and experimental studies on cancer and low frequency fields. On
the basis of that report and supplemeiltary information, the Criteria Group issued a
new criteria document (3) in October 1995. The essence of the new document was
the conclusion that although the scientific database was insufficient for developing
limits of exposures this might not exclude other steps to reduce exposure, for
example some form of "strategy of caution".
After the release of the Criteria Group statement, the government authorities
declared that they would not issue mandatory regulations, but that they supported
the principles of a strategy of caution. In this situation, it is necessary that those
who must make decisions regarding planning, buildings and the installation of
equipment should be guided with regard to caution strategies. The five
aforementioned authorities have for that purpose agreed upon the present
document.MATERIAL IN THE SSI NEWS MAY
copyri!1U:
IIJORN HOLM, INFORMATION OFFICE.
BE USED FREELY WITH AN APPROPRIATE
National Authorities Recommend Caution
The national authorities have agreed to recommend the following precautionary
principle:
ACKNOWLEDGEMENT.
ISSN qoo-8 SI 3
2 SSI news No2, 1996
If measures to generally reduce exposure can be taken
at reasonable expense and with reasonable consequences in all
other respects, an effort should be made to
reduce fields radically deviating from that which can
be considered to be normal in the environment concerned.
Where new electrical installations and
buildings are concerned, efforts should be made, already at the
planning stage, to design and position
them in such a way that exposure is limited. The overriding purpose
of the precautionary principle is eventually to reduce exposure to
magnetic fields in our surroundings, so as to reduce the risk of
injury to human beings."
What Is a Normal Magnetic Field Level?
"The magnetic field level in the environment concerned" refers to
the magnetic field level in areas where human beings can he
expected to be repeatedly present for a considerable length of time,
for example, housing, schools, day nurseries and workplaces. The
"normal magnetic field level" refers to the average obtained, after
calculation or several measurements, for the magnetic field in the
surroundings concerned and in conditions which can be
representative for the field level over a long period. The median
value for homes and day nurseries in major towns or cities is
approximately 0.1 ~T (microtesla). The values in smaller towns and
rural areas are approximately half of this (4). Close to power lines
and transformer stations, the magnetic fields are higher. Right
underneath a power line, the figure can be about 10 ~T. It is
estimated that some 0.5 per cent of the housing stock has a
magnetic field exceeding 0.2 ~T, owing to the proximity of electric
installations of different kinds. In the working environment the
levels are higher and tend to fluctuate more. A median value of 0.2
~T was found for a large number of occupational categories in a
Swedish study. Levels of hundreds of ~T can occur briefly for
certain individuals or working situations with a daily average of
one or two ~T, for example, for welders.
SEK 7 million (Swedish road administration), cancer from ionizing
radiation SEK 12 million (the Nordic radiation protection
authorities), and lung cancer from radon in dwellings SEK 2
million (National Board of Health and Welfare). Similar figures
from the United States amount to between SEK 5 million and 50
million, with the nuclear power industry accounting for the highest
figures and the traffic sector accounting for the lowest ones. In
some of the areas mentioned above, the causal relationships have
been made clear, the risks are well known and the effects of
funding inputs are calculable or quantifiable. It is, however, quite
easy to imagine an "imprudent - prudent avoidance" way of acting.
Examples of Cost Estimates
On average in Sweden and in most other industrialized countries,
one child in 25,000 per annum develops leukemia. Although the
hypothesis of the connection between the occurrence of child
leukemia and exposure to magnetic fields cannot be deemed to be
scientifically established, the observed risks can be used when
estimating an upper boundary for the cost to eliminate exposure. In
one of the Swedish epidemiological studies, it was observed that
children living close to power transmission lines ran a 2.7 higher
risk of developing leukemia than those living far away from such
transmission lines. This figure has also been applied to transformer
stations and stray currents in the following examples, for lack of
other risk estimates. We also assume a technical/economic lifetime
of 40 years for the measure taken and an interest rate of 4 per cent.
On these assumptions, it can be shown that the cost per statistical
case avoided will be R=735 K/N [SEK/case), where K is the cost
of the measure taken and N the number of individuals whose
exposure the measure eliminates.
It has to be noted that our examples ate only intended to
illustrate a calculation model fot arriving at a comparison between
different costs. Depending on the circumstances of the individual
case, there may be other solutions or bases for economic
calculation which are more appropriate. The calculation model
only deals with statistical cases, and many people will have to
derive benefit from a measure in order for public health to be
influenced.
What Is "Reasonable Expense"?
Human life cannot be valued in terms of money, but even so, it will
be readily understood that there are many situations where the
possibility for society or individuals to save lives or avert serious
illnesses is limited by the lack of
resources. Constraints on
resources are an inescapable
fact and do not reflect any
desire to put a price tag on
people's lives.
The amount which society is
ready to pay in order to save a
"statistical life" varies a great
deal from one sector of
society to another and from
one risk factor to another.
Some
benchmarks for expenditure
per fatality/casualty avoided
can be found in other areas, for
example death from road
accidents
Examples
,. Power Line Near to Multi-family Dwellings
An existing 220 kV power transmission line crosses a multifamily
housing area with 3°0 children living within a distance of the line
where the risk of child leukemia is presumed to increase through
proximity to the power line. The cost of replacing the power line
with another solution - a cable along an existing road - is SEK 60
million. If this measure is taken, the cost per case avoided, assuming
the estimated risk to he true, will be about SEK 15° million.
Calculations by local authorities may involve other aspects on
which a value can be placed, e.g. the fact of land being released for
alternative use.
SS! news No2, 1996 3
A transformer station in a school building causes elevated magnetic fields in three
classrooms. One possible means of reducing the magnetic fields is to line the area
with sheet metal. A measure of this kind costs about SEK 1,000/m2, materials and
labour included, which can mean a total cost of about SEK 200,000. Assuming
that the measure will reduce the exposure for 75 children, the cost per case
avoided will be less than SEK 2 million.
2. Transformer Station in a School Building The Development
of New Ideas in Physics
Dr Nils Ryde, Professor Emeritus, Department of
Physics, Chalmers University of Technology,
Gothenburg, Sweden has written a book which is
of interest to radiation protection specialists with
a background in physics, Professor Ryde has
played an important role in the development of
several areas of experimental physics. Professor
Ryde and his research team have studied, among
other things, the fission process and non-des-
tructive methods to measure the degree of burnup
of spent nuclear fuel. This work was supported
by the IAEA.
The new book (196 pages) is entitled
"Development of Ideas in Physics" and is
published by Almqvist and Wiksell International,
Stockholm, Sweden. The content covers atoms,
optical spectroscopy, X-ray spectroscopy,
quantum mechanics, neutron physics, atomic
models, neutrino physics, spinning particles,
fission as well as the origin of elements and anti-
matter. I warmly recommend this book for
reference collections in physics.
3. Stray Currents in Single-family Dwellings
A single-family dwelling has elevated magnetic fields which are caused by stray
currents in water pipes and electrical lines in the house. The cost to eliminate
these currents will be SEK 5,000. Assuming that there will be, on average, one
child living in the home over a period of 40 years, the cost per statistical case
avoided would be about SEK 4 million.
A 400 k V power transmission line is planned in a rural area. An effort has been
made at the planning stage to locate the line as favourably as possible, fo
4. Power Line in Rural Area
r
example from the viewpoint of persons living close by. It is intended to use a
power line structure, a T-pole, which is more advantageous from the viewpoint of
the magnetic field than the traditional transmission line strucrure. These measures
can be taken without any appreciable added expense or other consequences.
Even so, for 80 kilometres of its length, the line will pass within such a distance
of 71 scattered properties that the magnetic fields in the properties can be
considered to be increased. With a view to reducing the fields locally on each
property, the possibility is being investigated of using tuned screened circuits.
Every such circuit costs an estimated SEK 0.5 million. Assuming that, on
average, there is one child living on each property and there are no other
economic aspects to be taken into consideration, the cost per case avoided will be
about SEK 370 million. The cost per case will be the same if it is decided to
purchase the properties for an average of SEK 0.5 million each.
LARS PERSSON
Information Office
Irradiated Spices for
Sale in Sweden?
Conclusions
The precautionary principle recommends that measures should be considered
when the fields deviate strongly from what can be considered to be normal in the
environment concerned. The examples show that exposure reduction measures
can cost from a couple of million to several hundred million Swedish kronor per
statistical case of child leukemia avoided, provided that the risk estimates are
valid. It is obvious that the higher figures largely exceed what has normally been
spent for the reduction of similar risks in other areas. In the light of the large
uncertainties involved in this case, only the lower figures will probably be
considered realistic. The introduction of economic concepts will hopefully
provide a better basis for optimized political decisions.
In the 1997 budget proposal published recently,
the Swedish government declares that the
irradiation of spices and the import of already
irradiated spices should be permitted in Sweden
in the future. If this proposal is accepted by the
Swedish parliament, the absolute ban on all
irradiation of foodstuffs which currently exists
will be relaxed.
The European Community has banned the use
of ethylene oxide to kill pathogenic bacteria in
spices. Irradiation is currently the only
reasonable alternative to ethylene oxide.
However the irradiation of foodsruffs is a very
controversial political issue in Sweden. The fact
that the opponents of irradiation are not in favour
of the use of chemicals either makes the situation
even more bizarre. The opponents assert that the
only acceptable alternative is to promote more
hygienic handling and storage conditions in the
spice-producing countries.
JjONAS
KARLBERG X -rays and Radioactive
Substances
LARS-ERIK PAULSSON
Principal Scientist; Division of Non-ionising Radiation
This paper Includes several edited citations from the original booklet. Readers
interested in the full text can obtain a copy from 551. see page 15.
References
I. Kivisakk E.. Moberg l. "551 policy: Health risks from electromagnetic fields".
551 News No 2. February, 1993.
2. Hardel! L.. Holmberg B.. Malker H., Paulsson L-E.: "Exposure to extremely low frequency
electromagnetic fields and the risk of malignant diseases - an evaluation of epidemiological
and experimental findings", European J Cancer Prev, vol 4 (supplement I): 3-107 (1995).
3. The Criteria Group for Physical Risk Factors. Magnetic fields and cancer
- a criteria document. Arbete och Hatsa 1995: 13, pp 1-10. (in Swedish with English abstract)
4. Nissen J., Paulsson L-E.: "Magnetic fields in Swedish residences and day nurseries." in Supplement
from EMC-Zurich Electromagnetic Compatibility 1995, 11th International Zurich Symposium and
Technical Exhibition on Electromagnetic Compatibility 7-9 March, 1995, Zurich, p 139-143.
4 SSI news N02, 1996
103E L E C T R O P O L L U T I O NENVIRONMENT UNDER PRESSURE
Some people lay metal mats under their beds to neutralize the effects of electromagnetic fields
(EMFs), while others put their faith in glass pyramids. There are even people who sleep in a different
place every night – all for fear of “electropollution” (or “electrosmog”, as it is commonly known in
Switzerland). The reason for this concern is the unprecedented increase that has occurred in recent
years in the number and variety of EMF sources, whether from personal appliance use or from
commercial and industrial applications.
SLEEPLESS IN A SEA OF RADIATION?
There can be no doubting the fact that we are today surrounded by electromagnetic radiation.The culprits are mobile-telephone transmitters(known as “base stations”) and the mobile phonesthemselves, cordless telephones, radio and tele-vision transmitters, power lines, computers, radar,microwave ovens and equipment used in industryand medicine. Electropollution – or non-ionizingradiation (NIR), to give this phenomenon its cor-rect name – includes all forms of radiation which(in contrast to ionizing, radioactive radiation) donot have sufficient energy to modify atoms andmolecules. NIR occurs as an unwanted by-productaround electrical installations such as power linesand transformers and around electrical equipmentfor the home and office. In the case of transmit-ters and mobile phones, on the other hand, the
104SA
EFL
– EN
VIRO
NMEN
T S
WIT
ZERL
AND
2002
1 Hz 1 MHz1 kHz 1 GHz
HIGH FREQUENCYLOW FREQUENCY
Source: SAEFL
radiation actually provides the vehiclefor the transmission of information andis therefore technically unavoidable.
But it is precisely the erection of mo-bile telephone antennas in residentialareas that is arousing public anxietiesand protests. The opposition is mo-tivated both by a desire to protect thelandscape and by medical concerns.While on the one hand antennas can bea major blot on the landscape, there arealso growing fears among the popu-lation that the explosive growth inmultimedia communication and theattendant increase in electromagneticradiation could cause serious damageto health. It is unclear, however, quitehow many people blame mobile tele-phone antennas for physical ailments.What we do know is that over half ofthe population of Switzerland use mo-bile phones – and thousands of newsubscribers are joining them every day.
The same applies to projects involv-ing high-voltage power lines – only here the situation is aggravated by thefact that once such installations havebeen built, they will generally occupythe same corridor for decades to come.Electropollution is therefore a socio-political issue that is provoking pro-found controversy.
This is by no means an easy topic todeal with – probably because the scien-tific basis for this environmental phe-nomenon is not immediately apparent.
The Swiss “Ordinance relating to Protection from Non-Ionizing Radiation” (ONIR) con-
tains two types of limit values: exposure limit values and precautionary limit values.
Exposure limit valuesExposure limit values afford protection against scientifically established adverse health
effects. They take into account the total radiation that is present at a particular loca-
tion. They must be complied with in any location to which individuals might possibly
have access (even for short periods). Exposure limit values are internationally agreed
and compliance will not usually pose any problems in Switzerland.
Precautionary (installation) limit valuesThe precautionary principle, as enshrined in the Environmental Protection Law, dic-
tates that exposure must be low – in fact, it must be as low as is technically and oper-
ationally possible and economically acceptable. Installation limit values are substantially
lower than the exposure limit values. They apply to the radiation from a single instal-
lation and must be observed in locations where individuals spend prolonged periods
(e.g. homes, schools, hospitals). The installation limit value is fixed in accordance with
the technical possibilities afforded by the type of installation in question.
Exposure limit values for the frequency ranges of selected installations:Instal lat ion Exposure l imit value
Railways 16 2/3 Hz 300 µT; 10 000 V/m
High-voltage power lines 50 Hz 100 µT; 5 000 V/m
Radio broadcasting
transmitters 10-400 MHz 28 V/m
Mobile telephone 900 MHz 41 V/m
base stations 1800 MHz 58 V/m
UMTS base stations 2100 MHz 61 V/m
Installation limit values within the frequency ranges of selected installations:Instal lat ion Instal lat ion l imit value
Railways 1µT (24 hr mean)
High-voltage power lines 1 µT
Radio broadcasting transmitters 3 V/m
Mobile telephone 900 MHz 4 V/m
base stations 1800 MHz 6 V/m
UMTS base stations 2100 MHz 6 V/m
ONIR: Two l imit values – two terms
105E L E C T R O P O L L U T I O N
ENVIRONMENT UNDER PRESSURE
DIFFERENT APPROACHES TO LIMIT SETTINGThe setting of protection limits is based both on the published scientific studies and on
general experience of the biological effects of electropollution. However, one cannot
simply translate these findings directly into limit values without first subjecting them to a
process of evaluation. For example, it is necessary to decide whether a study has been
carried out in accordance with recognized scientific principles and is thus reliable, and
furthermore whether any identified effect is significant with respect to human health. This
evaluation is undertaken by specialists in the fields of biology, medicine and toxicology.
The conclusions reached by these review bodies and the exposure limits that are set
will vary according to the criteria applied and what degree of protection they are seeking
to achieve. Outlined below are two different ways of tackling this evaluation process.
Finally, a third approach is presented which is based not on biological effects, but on
the technical possibilities that exist for reducing electropollution.
The ICNIRP hazard reference levels. The International Commission on Non-Ionizing
Radiation Protection (ICNIRP) is a private, non-governmental organization which in 1998
published Guidelines on Limiting Exposure to EMFs. In formulating these guidelines, it
took into account only the biological effects which had repeatedly and reproducibly
been demonstrated in experimental research and which clearly pose a human health
hazard. In the view of the ICNIRP, the following are the only health effects that satisfy
this criterion:
• in the low-frequency range (electricity supply, railways): involuntary contraction of
muscles and disrupted nerve cell firing patterns; and
• in the high-frequency range (transmitter installations): excessive increases in body
temperature.
These are considered to be acute effects. Other effects for which a risk to health is not
clearly discernible, single observations and non-reproducible results were not taken into ac-
count when the ICNIRP limit values were set, nor were epidemiological studies considered.
Although the Commission did incorporate a safety factor when deriving its limit
values, this applies only to those particular effects that featured in its deliberations. The
ICNIRP limits are therefore limit values for protection against known hazards and not
precautionary limit values. As far as mobile telecommunications is concerned, they
relate exclusively to thermal effects.
Compliance with the ICNIRP exposure limits will certainly protect human beings
against the acute effects specified above. Given the limited nature of the data that were
used in deriving the ICNIRP limits and in view of experimental and epidemiological re-
search findings suggestive of athermal effects, it is questionable, however, whether pro-
tection is also afforded against other effects, and in particular against long-term effects.
The “Salzburg Resolution”. A different approach to the establishment of exposure
limits is followed by the so-called “Salzburg Resolution”. At an international conference
held in Salzburg in June 2000, critical scientists and representatives of the public
health authorities were afforded their first opportunity to meet at international level.
They discussed the current state of knowledge regarding exposure and the health
effects of high-frequency electromagnetic fields, addressing these topics both from a
public health standpoint and in the light of the precautionary principle. In assessing the
problems involved, they also took into account scientific findings that tend to suggest
a risk to health, but do not as yet furnish any definitive evidence. High priority was
accorded to epidemiological studies, since investigations of this kind focus on actual,
everyday situations involving human exposure.
The upshot of these deliberations is the “Salzburg Resolution on Mobile Telecommu-
nication Base Stations”. The signatories to the Resolution conclude that there is cur-
rently evidence to suggest that even extremely low levels of radiation could have adversecontinued on p. 106
Radiation is, after all, something thatwe can neither hear, feel nor smell.While we may perhaps feel its effects,we would need to explore some highlycomplex areas of physics and medicinein order to investigate the underlyingcauses.
Moreover, there is still great uncer-tainty in the scientific community overthe possible effects of non-ionizingradiation on health. In the case of ex-posure to high levels of radiation, theharmful effects are both proven andacknowledged. As regards low-level ex-posure, however, the picture is lessclear. Although biological effects havebeen demonstrated in the laboratory,the scientists are still arguing overwhether or not these are harmful. Stat-istical comparisons have been madebetween population groups subjectedto high and low levels of exposure. Thefindings of such studies are contradic-tory. In some cases, an increased risk ofdiseases such as leukaemia or sleep disorders is discovered, whereas otherstudies show nothing untoward. Whatknowledge we do have can be likenedto a jigsaw puzzle for which all but afew pieces are missing and no coherentexplanation has been advanced.
The fact that even the scientists can-not agree over the significance of theirfindings merely fuels the disputes thatare raging between operators and criti-
continued on p. 107
106SA
EFL
– EN
VIRO
NMEN
T S
WIT
ZERL
AND
2002
An illustration of electromagnetic radiation in the vicinity of a high-power mobile-telephone base station mounted on a flat-roofed building. The antenna “focuses” theradiation in a similar way to a car headlamp and steers it in the required directions. In the area shaded black, the exposure limit value is exceeded. Entry to this area isprohibited – even for short periods. Inside the area shaded pink, the installation limit value is exceeded. No facilities classified in the ONIR as “places of sensitive use”(homes, schools, hospitals, offices, children's playgrounds, etc.) may be sited within this area. In the blue and white area, the installation limit value is complied with – andthe same applies inside the building, since the concrete roof attenuates the level of radiation. The additional lines indicating levels of twice and half the installation limitvalue serve to illustrate how radiation diminishes as the distance and deviation from the direction of maximum radiation increase. The intensity of radiation in the white areaamounts to less than one eighth of the installation limit value.
Radiat ion near a mobi le-telephone base stat ion
–10 0 10 20 30 40 50 60 70 80 90 100
60
50
40
30
20
10
0
effects on health and therefore that a zero-effect threshold does not
exist. Recommendations of specific limit values are therefore prone
to considerable uncertainties – they contend – and should be con-
sidered preliminary. Despite this difficulty, the Resolution does
recommend a precautionary limit value for radiation from mobile
telecommunications equipment. This is around 100 times lower
than the ICNIRP's “thermal” exposure limit. The Salzburg limit
value is a biologically based precautionary limit value founded on
the rationale that biological effects do exist in the presence of low-
level radiation. While it is uncertain whether these effects are,
indeed, harmful, the fact remains that they could very well be. As
a precaution, therefore, exposure to radiation should remain below
these “suspected effect” thresholds.
Avoidable exposures are to be avoided. The third approach is
based not on biological effect thresholds, but on the technical pos-
sibilities that exist for reducing radiation. In the Swiss Environmen-
tal Protection Law, for example, it is stipulated that radiation must,
as a precautionary measure, be limited to the maximum extent
that is both technically and operationally possible, and economic-
ally acceptable. Experience tells us that exposure to electropollution
can, in most cases, be kept far below the ICNIRP hazard reference
levels at an affordable cost, especially in places where individuals
spend prolonged periods. This experience can likewise be trans-
lated into limit values, which in this particular case will be precau-
tionary limit values based on technical and economic consider-
ations.
The decision as to which approach is to be followed in setting
exposure limits is based not on science but on political consider-
ations. Essentially, it hinges on what degree of protection is being
sought. Above all, the politicians will have to answer the question
of how they propose to deal with those risks that are classified as
being either “uncertain” or “questionable”. This question assumes
particular importance in such areas as mobile telecommunica-
tions, where virtually the entire population is exposed to this form
of radiation.
In the Ordinance relating to Protection from Non-Ionizing Radi-
ation, the Federal Council has opted for the following approach:
• To afford protection against proven damage, it has adopted the
ICNIRP's hazard reference levels.
• As far as potentially harmful effects are concerned, it has taken
the precautionary step of setting installation limit values based
on technical and economical considerations.
Metres
Metres
D i r e c t i o n o f m a x i m u m r a d i a t i o n
Instal lat ion l imit value
0.5x the instal lat ion l imit value
Exposure l imit value
2x the instal lat ionl imit value
107E L E C T R O P O L L U T I O N
ENVIRONMENT UNDER PRESSURE
cal pressure groups. The industry isdemanding proof of harmful effects be-fore it will take steps to limit exposure.Environmental organizations, certainmedical practitioners and members ofthe public, on the other hand, object tothe public being used as guinea pigs.They are demanding that a new techno-logy should be proven not to be harm-ful before it is introduced.
Uncertainty is no excuse for inactivity. Inspite of all the uncertainty, limits needto be imposed without delay. Becauseone thing is absolutely clear: exposureto radiation will continue to increase. Itis now a matter of establishing what ex-posures are acceptable and what arenot. The Federal Council has alreadyresponded by issuing exposure limitsfor proven damage and precautionaryvalues for potentially harmful effects.In doing so it fulfilled its mandateunder the Environmental ProtectionLaw (USG), which stipulates that elec-tropollution must, as a precautionarymeasure, be limited to the maximumextent that is technically and economic-ally feasible, but at least to such an ex-tent that it is neither harmful nor cons-titutes a nuisance to human beings.
The “Ordinance relating to Protec-tion from Non-Ionizing Radiation(ONIR)” came into force on 1 February2000 and is considered to be among themost stringent regulations of its kind inEurope.
The ONIR contains two types oflimit values. The first are the so-calledinstallation limit values, which aim toplace a precautionary ceiling on radi-ation emissions from a particular instal-lation. Secondly there are the exposurelimit values, which are based on in-ternationally recognized, scientificallyverified recommendations.
However, the Ordinance does notonly contain regulations governing in-stallations that produce electropollution,but also provisions relating to spatialplanning. In future, new building zonesmay only be designated in locationswhere the installation limit value is notexceeded.
Government supports product labelling.Mobile phones are neither covered bythe Environmental Protection Law norby the ONIR. The limitation of radi-ation from mobile phones and otherelectrical appliances requires inter-national technical regulations, whichSwitzerland cannot issue unilaterally.One effective way of motivating pro-ducers to develop low-emission appli-ances and to inform consumers aboutthe degree of exposure from theirmobile phones is for them to declareemissions. The federal government sup-ports the efforts of the consumer organ-izations to bring about the introductionof such product labelling.
OUTLOOKExposure to non-ionizing radiation willcontinue to increase – as will the var-iety of EMF sources – owing to the
Mobile telephones emit electromagnetic waves at frequencies of 900 or 1800 MHz. The radiation there-fore lies in the microwave range, which can cause heating of body tissue. The internationally recom-mended exposure limits for mobile phones are basedon this thermal effect. Even if the thermal exposure limits are complied with, so-called athermal effectscan occur inside the head of the mobile phone user.Intensive research is currently underway to establish whether these phenomena have a detrimental effecton health. The key question is whether radiation frommobile phones promotes the development of brain tumours.
countless new technologies that are setto arrive on the market over the nextfew years.
The principle to be adopted in devel-oping new technologies must thereforebe that radiation should be kept to aminimum. Ideally, health risks will infuture be identified before new appli-cations are introduced. This requires athorough understanding of the possibleeffects of NIR on the human body.Such knowledge will, of course, taketime to accumulate.
Even if our level of knowledge doesimprove, there is no such thing as zerorisk – nor has there ever been through-out the entire history of industrial-ization. Because we shall thereforealways be left with a “residual risk”,new technologies must be monitoredafter their introduction by means of ap-propriate research programmes. ■
Radiat ion threat to mobi le phone users?
Use
ICNIRP Statement
USE OF THE ICNIRP EMF GUIDELINES
(March 31, 1999)
Introduction and purpose
Since the publication of the ICNIRP guidelines for limiting EMF exposure up to 300 GHz1) several institutions have criticized the guidelines as lacking clear interpretation on exposure safety or direct application to equipment in existence. Concerns have also been expressed about the use of safety factors, precautionary aspects and long term exposure as well as points not included in the ICNIRP guidelines. This STATEMENT from the International Commission on Non-Ionizing Radiation Protection (ICNIRP) addresses these concerns and clarifies points such as the criteria used for evaluating scientific studies, the development and practical application of the guidelines, the need for special technical advice, how to consider social and economic aspects and how to handle current research. This statement clarifies the way in which the guidelines should be used in a regulatory and legislative context. Some questions have already been addressed by publications in Health Physics.2)
Quality criteria for evaluating scientific studiesDevelopment of guidelines on exposure limits requires a critical, in-depth evaluation of the established scientific literature using internationally accepted quality criteria. Experimental results can only be accepted for health risk assessment if a complete description of the experimental technique and dosimetry are provided, all data are fully analyzed and completely objective, results show a high level of statistical significance, are quantifiable and susceptible to independent confirmation, and the same effects can be reproduced by independent laboratories.3) When evaluating epidemiological studies, quality criteria are based on the need to evaluate, reduce or adjust for the influence of chance, bias and confounding. Cases of disease should be identified independent of exposure, and exposure should be assessed in a way not related to disease status. The influence of other variables should be handled in the design or in the analysis of the study. Any data on which the conclusions are based should be reported.4) The final overall evaluation of the evidence should include the assessment of the strength and consistency of the association between EMF exposure and biological effects from both epidemiological and experimental studies, as well as the plausibility that biological systems exposed to EMF fields could likely manifest biological effects. It is also necessary to identify which EMF-induced biological effects are to be considered a hazard to the human health.
The role of ICNIRPInternational recommendations of health-based guidance to limit exposure require an assessment of possible adverse health effects using established scientific and medical knowledge. This must be based mainly on the science and should be free of vested interest. ICNIRP, as an independent scientific body comprising all essential scientific disciplines, is qualified to carry out the task of assessing possible adverse health effects, together with WHO. ICNIRP is the formally recognized non-governmental
http://www.icnirp.de/documents/Use.htm (1 of 5) [03.Jun.05 8:58:11 AM]
Use
organization in NIR protection for the WHO, the International Labour Organization (ILO), and the European Union (EU) and maintains a close liaison and working relationship with these international bodies as well as IEC and CIE for the optical region and with other bodies engaged in NIR protection. ICNIRP's review process includes Standing Committees and additional experts. The consultation process is extensive and includes IRPA national bodies and other independent scientists and organizations worldwide. ICNIRP works in conjunction with the WHO to assess health effects of exposure to NIR, which are published in the WHO Environmental Health Criteria monographs, and uses the results of this assessment to draft health-based exposure guidelines.
Developing of exposure guidelinesRecently the ICNIRP adopted guidelines on limits of EMF exposure for frequencies up to 300 GHz.1)
While all the scientific literature was reviewed, the only adverse effects on humans that were fully verified by a stringent evaluation were short term, immediate health consequences such as stimulation of peripheral nerves and muscles, functional changes in the nervous system and other tissues, shocks and burns caused by touching conducting objects, and changes in behavior caused by elevated tissue temperatures. There are also data for chronic low level exposure that indicate that there may also be other health effects. It is, however, ICNIRP's view that in the absence of support from laboratory studies the epidemiological data are insufficient to allow an exposure guideline to be established. Limiting values are given as basic restrictions and reference levels. Basic restrictions directly relate to established health effects. Appropriate safety factors are included. Reference levels are derived from the basic restrictions for worst-case exposure situations and are in quantities that can be easily measured. They provide levels that can be used to determine compliance with the basic restrictions. By using the system of basic restrictions and derived reference levels, the new ICNIRP guidelines offer flexibility for many exposure situations.
The use of safety factorsIt is ICNIRP's view that safety factors in the ICNIRP EMF guidelines should relate to the precision of science, reflecting the amount of established information on biological and health effects of EMF exposure. Numerically uncertain relationships between established effects and exposure levels result in higher safety factors and vice versa. As with the assessment of adverse health effects, setting safety factors should be free from vested interests. There is no rigorous basis for determining precise safety factors. Safety factors are based on a conservative value judgment by experts. In the new ICNIRP guidelines the safety factors vary from approximately 2 to > 10 (see next section) depending upon the extent of uncertainty in knowledge of thresholds for health effects for direct and indirect field interaction at various frequencies. For the purpose of defining guidelines for protection, a simplified and conservative approximation of the frequency dependence of biological effects was chosen. In general, threshold field levels for indirect effects (e.g., response to contact currents) are better defined than for direct effects, and hence, less conservative safety factors are required.Public guidelines include additional safety factors of 2 to 5 relative to occupational guidelines (depending upon the frequency and the relevant dosimetric parameters). Occupational health standards are aimed at protecting healthy adults exposed as a necessary part of their work, who are aware of the occupational risk and who are likely to be subject to medical surveillance. General population guidelines must be based on broader considerations, including health status, special sensitivities, possible effects on the
http://www.icnirp.de/documents/Use.htm (2 of 5) [03.Jun.05 8:58:11 AM]
BCTC – 2005 Transmission system Capital Plan F2006 to F2015
IRAHVOL Information request #2, June 3, 2005 1. Evaluation of HVDC Light Alternative Transgrid Solutions evaluation of HVDC Light assumes that the maximum HVDC Light rating available is 330 MW, hence two complete systems would be required to reach the desired capacity per stage of 600 MW. Although 330 MW is the highest capacity installed to date, ABB information provided to IRAHVOL on May 18th, 2005 (It is time to connect, attached) describes ratings of 550MW with 150kV modules M6, and ratings of 720MW and 1100MW with 300kV modules M8 and M9. 1.1 Please provide an evaluation of HVDC Light technology based on these
ratings and project requirements for both phase 1 and phase 2, including the possibility of advancing phase 2 to supply 1100MW using 300kV Modules M9 in phase 1.
1.2 Please describe technical differences between 330MW ratings installed to
date and 550MW, 720MW and 1100MW ratings. 1.3 Please describe ABB guarantee for turn-key installations at above ratings. 1.4 Please describe services and products supplied by ABB. HVDC Light appears to be able to provide power control for normal optimal dispatch to optimize the loading on parallel paths and avoid overload of the cables following contingencies. We assume BCTC plans to do this with AC cables by using series connected phase angle regulators. 1.5 Please provide an evaluation of HVDC Light alternative versus AC alternative in this respect. For network security BCTC may not allow local generation to go off-line, and pay a premium for VI generation for reliability purposes. It appears that HVDC Light technology may be able to achieve secure operation without the need for sub-optimal generation dispatch. While it is true that AC cables would strengthen the AC network as well, something might need to be done to regulate the voltage on the south end of the island due to the excess charging current from the AC cables. This appears not to be a problem with HVDC Light since it can regulate the voltage.
HVDC Light appears to be able to provide voltage support on the Mainland and Vancouver Island. Reactive power support from the converter terminals, within the MVA rating of the converters, can increase overall transfer capability when remote from generation (or during periods when local generation is off-line). Dr. Rashwan attempts to discount this advantage on two fronts. First, he states that the capability is limited to within the MVA rating of the converter. This is just like the voltage support available from a generator. If the DC power is backed off by 10 - 20 % with the balance flowing on the 500 kV AC cables the reactive power available from the converters for dynamic voltage support is significant and useful. Second, he states that the AC system is strong at both ends therefore the reactive power available from the terminal is insignificant since the voltage is well-regulated presumably from generation. On the one hand he says the voltage support capability of the DC is relatively insignificant, while on the other hand he states that shunt compensation and synchronous condensers are used for voltage support.
1.6 Please provide an evaluation of the HVDC Light alternative versus AC alternative including capital, operating, and environmental costs of voltage support measures proposed and/or already existing on the Mainland and Vancouver Island. 2. Criteria for evaluation 2.1 Since HVDC Light technology appears to have many advantages over the AC alternative in terms of environmental, aesthetic, and social and economic impacts, please provide a multiple account evaluation to compare not only the initial costs but also all other costs, including environmental and socio-economic costs of HVDC Light and AC alternatives. In particular, provide a qualitative and, wherever possible, quantitative evaluation of the two technologies on the basis of: 2.2 types and levels of electromagnetic fields (EMF) generated 2.3 visual impacts of the land portions of the installations 2.4 safety of the land portions of the installations (fire risk, injuries, inductive currents) 2.5 environmental impacts of sea cables (fluid leakage, footprint, EMF)
2.5.1 Please provide the schedule and amount of insulating alkylbenzene fluid added to existing 138kV AC cables since installation for operational purposes and due to leakage. 2.6 economic impacts due to public perception of EMF generated (property devaluation, loss of business –daycares, campgrounds) 2.7 possible increase of the cost of the project due to public opposition and/or legal action based on the potential and/or perceived health risk associated with EMF generated. 2.7.1. Please state the estimated cost penalty to be added to the capital cost of the project as a result of BCTC’s decision to not recommend constructions of overhead lines on the existing right of way in Tsawwassen. 3 Clarifications of TSCP Application IR#1 Question 1 1.1. refers to the attached World Health Organization fact sheet 263. The same definition of ICNIRP exposure guidelines appears in the ICNIRP statement, Use of Guidelines (excerpt attached). Canada currently does not have guidelines for long-term exposure to EMF, however Switzerland and Sweden amongst other countries and states have guidelines in regards to new installations that are aimed at minimizing human long-term EMF exposure on the basis of potential health risks (attached). In Canada the Federal-Provincial-Territorial Radiation Protection Committee issued a statement on the issue of Power-Frequency Magnetic Fields and Childhood Leukemia (attached) in which it states “The outcome of a recently conducted pooled analysis of several epidemiological studies shows a two-fold increase in the risk of leukemia in children living in homes, where the average magnetic field levels are greater than 0.4 microtesla (4 milligauss). However it continues, “epidemiological evidence to date is not strong enough to justify a conclusion that EMFs in Canadian homes, regardless of locations from power lines, cause leukemia in children”. The findings do not put an end to doubt or question. 3.1 Do you know that long-term exposure to extremely low frequency EMF above 2 milligauss is safe? 3.2.If we do not know whether or not EMF cause childhood leukemia or other diseases do you think that with cost effective alternatives the option which eliminates risk should be chosen?
3.3 Please provide spot measurements of EMF levels on Salt Spring under the existing 138kV Ac overhead lines and at different distances nearby. 3.4 Please provide spot measurements of EMF levels in proximity to existing installations in British Columbia of double circuits 138kV running at capacity and 230kV transmission lines. 3.4 Please provide a history of the power carried along the existing 138kV circuits through Salt Spring Island for the last 10 years. 4. Routing alternatives The objectives of the project as described on page iv of the Project Description (prepared by BC Hydro Engineering, Jan 2005) are: 1. to provide system reliability on VI 2. to meet current and future electricity demand on VI 3. to reduce on going operating and maintenance costs 4. to reduce environmental impacts resulting from cable failures and
maintenance activities 5. to decrease exposure to system failures due to seismic events These objectives as well as the needs of the stakeholder groups and the objectives of the regulatory agencies involved do not appear to be all satisfactorily addressed with the current proposal. Alternative solutions may be: A.Generation on Vancouver Island based on the use of renewable resources B. Use of HVDC Light technology for a transmission link along the existing right of way between Arnott and VIT terminals C. Use of AC or HVDC Light technology for a transmission link along an alternative route between Arnott and VIT D. Use of AC or HVDC Light technology for a transmission link along alternative route between a terminal on Vancouver Island and a terminal elsewhere 4.1 Please provide digital bathimetric data of the existing right of way between Arnott and VIT terminals. 4.2 Please provide digital bathimetric data of possible alternative route from Arnott to VIT via Porlier Pass and Samson Narrows along an all submarine route through the Gulf Islands and landing at Crofton substation.
4.3 Please provide digital bathimetric data of possible alternative route from Arnott to VIT via new land right of way across Galiano Island below Porlier Pass, south of Secretary Island, North of Salt Spring Island, through Houston Passage landing at Crofton substation. 4.4 Please provide digital bathimetric data of possible alternative route from Arnott to Pike terminals along an all submarine route through the Gulf Islands. 4.5 Please provide digital bathimetric data of possible alternative route from Cypress to VIT terminals via new land right of way across Galiano Island below Porlier Pass, south of Secretary Island, North of Salt Spring Island, through Houston Passage landing at Crofton substation. 4.6 Please provide an evaluation of how the objectives of VITRP may be addressed by an HVDC Light transmission link between CCB and DMR terminals. 4.7 Please provide an evaluation of how the objectives of VITRP may be addressed by an HVDC Light transmission link between VI and the Olympic Peninsula. 4.8 Would BCTC be able to export and/or import power to and from the US via the proposed VITRP and the proposed Juan de Fuca interconnector? 4.9 For the portion of the project relative to power supply to Southern Gulf Islands, please provide a multiple account evaluation to compare not only the initial capital costs but also all other maintenance and operation, environmental and socio-economic costs of alternative supply from Vancouver Island versus proposed 230KV AC system. 5. Public participation In its public planning informational material (copy attached) BCTC states “it is committed to an open and transparent process that ensures stakeholders are informed and actively involved in discussions about major transmission initiatives in British Columbia”. 5.1 Please provide the date of the commencement of planning activities for the increased supply to Vancouver Island via a new transmission link. 5.2 Please provide the date of BCTC notification of the Vancouver Island Transmission Reinforcement Project to Gulf Island residents and local governments.
5.3 Please provide copies of requests for meetings from IRAHVOL and Gulf Islands local governments and a list of public meetings held since initial notification. 5.4. Please provide a schedule for public planning for VITRP from notification to Gulf Island residents to submission of CPCN application.
Event list
SLD for a typical HVDC Light station
WHO | Electromagnetic fields and public health: extremely low frequency fields and cancer
All WHO
This site only
Home
About WHO
Countries
Health topics
Publications
Research tools
WHO sites
Media centre
News
Events
Fact sheets
Multimedia
Contacts
Media centre
WHO > WHO sites > Media centre > Fact sheets
printable version
Fact sheet N°263October 2001
Electromagnetic fields and public health: extremely low frequency fields and cancer
Electromagnetic fields and public health: extremely low frequencyFull text
In 1996, the World Health Organization (WHO) established the International Electromagnetic Fields (EMF) Project to address the health issues associated with exposure to EMF. The EMF Project is currently reviewing research results and conducting risk assessments of exposure to static and extremely low frequency (ELF) electric and magnetic fields. WHO plans to conduct an evaluation of all health effects from ELF field exposure in 2002-3.
Whenever electricity is conducted through transmission lines, distribution lines or is used in appliances, both electric and magnetic fields exist close to the lines or appliances. The power frequency used is 50 or 60 Hz. Use of electric power has become part of everyday life. However, questions have been raised as to whether these and other ELF fields are carcinogenic.
The International Agency for Research on Cancer (IARC) -- a specialized cancer research agency of WHO -- has recently concluded the first step in WHO's health risk assessment process by classifying ELF fields with respect to the strength-of-the-evidence that they could cause cancer in humans.
This Fact Sheet updates findings of recent reviews on the health effects of static and ELF electric and magnetic fields conducted by IARC (June 2001), by the Health Council of the Netherlands (May 2001), and by an expert Advisory Group of the National Radiological Protection Board in the United Kingdom (AGNIR) (March 2001).
IARC evaluation
In June 2001, an expert scientific working group of IARC reviewed studies related to the carcinogenicity of static and ELF electric and magnetic fields. Using the standard IARC classification that weighs human, animal and laboratory evidence, ELF magnetic fields were classified as possibly carcinogenic to humans based on epidemiological studies of childhood leukaemia. Evidence for all other cancers in children and adults, as well as other types of exposures (i.e. static fields and ELF electric fields) was considered not classifiable either due to insufficient or inconsistent scientific information.
"Possibly carcinogenic to humans" is a classification used to denote an agent for which there is limited evidence of carcinogenicity in humans and less than sufficient evidence for carcinogenicity in experimental animals.
http://www.who.int/mediacentre/factsheets/fs263/en/ (1 of 4) [27.May.05 10:01:19 AM]
WHO | Electromagnetic fields and public health: extremely low frequency fields and cancer
This classification is the weakest of three categories ("is carcinogenic to humans", "probably carcinogenic to humans" and "possibly carcinogenic to humans") used by IARC to classify potential carcinogens based on published scientific evidence. Some examples of well-known agents that have been classified by IARC are listed below:
Classification Examples of agents
Carcinogenic to humans Asbestos
(usually based on strong evidence of carcinogenicity in humans) Mustard gas
Tobacco (smoked and smokeless)
Gamma radiation
Probably carcinogenic to humans Diesel engine exhaust
(usually based on strong evidence of carcinogenicity in animals) Sun lamps
UV radiation
Formaldehyde
Possibly carcinogenic to humans Coffee
(usually based on evidence in humans which is considered credible, but for which other explanations could not be ruled out)
Styrene
Gasoline engine exhaust
Welding fumes
ELF magnetic fields
Do ELF fields cause cancer?
ELF fields are known to interact with tissues by inducing electric fields and currents in them. This is the only established mechanism of action of these fields. However, the electric currents induced by ELF fields commonly found in our environment are normally much lower than the strongest electric currents naturally occurring in the body such as those that control the beating of the heart.
Since 1979 when epidemiological studies first raised a concern about exposures to power line frequency magnetic fields and childhood cancer, a large number of studies have been conducted to determine if measured ELF exposure can influence cancer development, especially leukaemia in children.
There is no consistent evidence that exposure to ELF fields experienced in our living environment causes direct damage to biological molecules, including DNA. Since it seems unlikely that ELF fields could initiate cancer, a large number of investigations have been conducted to determine if ELF exposure can influence cancer promotion or co-promotion. Results from animal studies conducted so far suggest that ELF fields do not initiate or promote cancer.
However, two recent pooled analyses of epidemiological studies provide insight into the epidemiological evidence that played a pivotal role in the IARC evaluation. These studies suggest that, in a population exposed to average magnetic fields in excess of 0.3 to 0.4 •T, twice as many children might develop leukaemia compared to a population with lower exposures. In spite of the large number data base, some uncertainty remains as to whether magnetic field exposure or some other factor(s) might have accounted for the increased leukaemia incidence.
Childhood leukaemia is a rare disease with 4 out of 100,000 children between the age of 0 to 14
http://www.who.int/mediacentre/factsheets/fs263/en/ (2 of 4) [27.May.05 10:01:19 AM]
WHO | Electromagnetic fields and public health: extremely low frequency fields and cancer
diagnosed every year. Also average magnetic field exposures above 0.3 or 0.4 •T in residences are rare. It can be estimated from the epidemiological study results that less than 1% of populations using 240 volt power supplies are exposed to these levels, although this may be higher in countries using 120 volt supplies.
The IARC review addresses the issue of whether it is feasible that ELF-EMF pose a cancer risk. The next step in the process is to estimate the likelihood of cancers in the general population from the usual exposures and to evaluate evidence for other (non-cancer) diseases. This part of the risk assessment should be finished by WHO in the next 18 months.
International guidelines
International guidelines on exposure limits for all EMF have been developed by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) - a non-governmental organization (NGO) in official relations with WHO and a partner in WHO's International EMF Project. While the ICNIRP guidelines for EMF exposure are based on comprehensive reviews of all the science, the limits are intended to prevent health effects related to short-term acute exposure. This is because ICNIRP considers the scientific information on potential carcinogenicity of ELF fields insufficient for establishing quantitative limits on exposure.
Some national responses
Regulatory policies for agents classified as possible carcinogens vary by country and by particular agent. The carcinogenic evaluation and classification of an agent by IARC does not automatically trigger a national regulatory response. While gasoline exhaust and coffee have been classified as possible human carcinogens, there has been a significant response by government to reduce gasoline engine exhausts, but there has not been any effort to limit intake of coffee.
In response to increasing public concern over health effects from EMF exposure, several countries have established their own scientific reviews prior to the IARC evaluation. Already in 1998, a working group examining the issue for the US National Institute of Environmental Health Sciences (NIEHS) classified ELF magnetic fields as possibly carcinogenic to humans. The US government agency has since recommended "passive regulatory action", described as continued information and education of the public and encouraging power utilities to voluntarily reduce exposure to people where possible.
In the United Kingdom, an Advisory Group on Non-Ionising Radiation recently reported to the National Radiological Protection Board (NRPB) on the topic of power frequency EMF and the risk of cancer (AGNIR, 2001). It concluded that while the evidence is currently not strong enough to justify a firm conclusion that EMF fields cause leukaemia in children, the possibility remains that intense and prolonged exposures to magnetic fields can increase the risk of leukaemia in children. Further, they provided research recommendations. The Health Council of the Netherlands, a major scientific advisory body of the Netherlands government, reached similar conclusions.
WHO's response
While the classification of ELF magnetic fields as possibly carcinogenic to humans has been made, it remains possible that there are other explanations for the observed association between exposure to ELF magnetic fields and childhood leukaemia. In particular, issues of selection bias in the epidemiological studies and exposure to other field types deserve to be rigorously examined and will likely require new studies. WHO therefore recommends a follow-up, focused research programme to provide more definitive information. Some of these studies are currently being undertaken and results are expected over the next 2-3 years.
WHO's EMF Project aims to help national authorities balance the benefits of electrical technology against possible health risks, and to help them decide what protective measures may be needed. It is especially difficult to suggest protective measures for ELF fields because we do not know what field characteristic might be involved in the development of childhood leukaemia and therefore need to be reduced, or even if it is the ELF magnetic fields that are responsible for this effect. One approach is to have voluntary policies that aim to cost-effectively reduce exposure to ELF fields. This has been discussed in the WHO Backgrounder issued March 2000.
Some precautionary measures are outlined below:
Further reading
http://www.who.int/mediacentre/factsheets/fs263/en/ (3 of 4) [27.May.05 10:01:19 AM]
WHO | Electromagnetic fields and public health: extremely low frequency fields and cancer
● Government and industry: These entities should be cognisant of the latest scientific developments and should provide the public with balanced, clear and comprehensive information on potential EMF risks, as well as suggestions for safe and low cost ways to reduce exposures. They should also promote research that will lead to better information from which assessments of health risk can be made.
● Individuals: Members of the general public might choose to reduce their EMF exposure by minimizing the use of certain electrical appliances or by increasing distance to the sources that can produce relatively high fields.
● Consultation with local authorities, industry and the public when siting new power lines: Obviously power lines must be sited to provide power to consumers. Siting decisions are often required to take into account aesthetics and public sensibilities. However, siting decisions should also consider ways to reduce peoples' exposure.
● An effective system of health information and communication among scientists, governments, industry and the public is needed to help raise general awareness of programmes to deal with exposure to ELF fields and reduce any mistrust and fears.
● AGNIR (2001) Advisory Group on Non-Ionising Radiation, Power Frequency Electromagnetic Fields and the Risk of Cancer. National Radiological Protection Board (UK) 2001.
● Health Council of the Netherlands (2001). Electromagnetic fields: Annual Update 2001.● ICNIRP (1998) International Commission on Non-Ionizing Radiation Protection Guidelines for
limiting exposure to time varying electric, magnetic and electromagnetic fields (up to 300 GHz). Health Physics 74(4), 494-522.
● Portier CJ and Wolfe MS (eds.), National Institute of Environmental Health Sciences of the National Institute of Health. Assessment of health effects from exposure to power-line frequency electric and magnetic fields. NIEHS Working Group Report, Research Triangle Park, NC, USA, NIH Publication No. 98-3981, 1998.
● Repacholi M and Greenebaum B (eds.), Interaction of static and extremely low frequency electric and magnetic fields with living systems: health effects and research needs. Bioelectromagnetics 1999; 20: 133-160.
● WHO Backgrounder on Cautionary Policies, March 2000
RELATED LINKS
- The International Electromagnetic Fields Project
- Electromagnetic fields
For more information contact:
WHO Media centre Telephone: +41 22 791 2222 E-mail: [email protected]
Employment | Other UN Sites | Search | Suggestions | RSS | Privacy
© World Health Organization 2005. All rights reserved
http://www.who.int/mediacentre/factsheets/fs263/en/ (4 of 4) [27.May.05 10:01:19 AM]
Federal-Provincial-Territorial Radiation Protection Committee – Canada
Response Statement to the Issue of Power-Frequency Magnetic Fields and
Childhood Leukemia – Issued on January 20, 2005
The Federal-Provincial-Territorial Radiation Protection Committee (FPTRPC) is
aware of concerns about possible health risks from exposure to power frequency
electric and magnetic fields (EMFs). In response, the FPTRPC developed a
Position Statement to address the issue*. Of particular interest is the risk of cancer
from living near power lines and other sources of EMFs. These concerns appear to
arise as a result of the controversial and contradictory findings in scientific
research, especially from epidemiological studies.
The outcome of a recently conducted pooled analysis of several epidemiological
studies shows a two-fold increase in the risk of leukemia in children living in
homes, where the average magnetic field levels are greater than 0.4 microtesla (4
milligauss)†. The explanation for this elevated risk estimate is unknown, but the
authors of the pooled analysis suggest that it may be accounted for, in part, by
selection bias of cases and controls in the original studies used for the pooled
analysis. However, the number of subjects in the greater-than-4-milligauss group
is very small, and thus the significance of the finding is questionable. More refined
statistical and epidemiological methods will be needed to clarify this finding.
Further, no mechanism has been identified in the research literature that supports
the suggestion that these fields can cause or promote the development of cancer.
It is the opinion of FPTRPC that the epidemiological evidence to date is not strong
enough to justify a conclusion that EMFs in Canadian homes, regardless of
locations from power lines, cause leukemia in children.
* Position Statement for the General Public on the Health Effects of Power-
frequency (60 Hz) Electric and Magnetic Fields; issued by the Federal Provincial
Territorial Radiation Protection Committee – January 20, 2005
†Ahlbom A, Day N, Feychting M, Roman E, Skinner J, Dockerty J, Linet M,
McBride M, Michaelis J, Olsen JH, Tynes T and Verkasalo PK. A pooled analysis
of magnetic fields and childhood leukaemia. Br J Cancer. 2000;83(5):692-698.
Magnetic fields... A NEW GUIDE POR DECISIONS ON LOW-PREQUENCY ELECTRIC AND MAGNETIC
PIELDS HASED ON UNCERTAIN HEALTH EHECTS
CONTENTS 2/1996
NEW PRESIDENT OP NSRP
Asker Aarkrog has been appointed new president
of the Nordic Society for Radiation Protection.
PROTECTING THE ENVIRONMENT
Radiation protection of nature - impressions
from an international symposium in Stockholm.
8
The Swedish Radiation Protection Institute, the National Board of Occupational Safety
and Health, the National Board of Housing, Building and Planning, the National
Electrical Safety Board, and the National Board of Health and Welfare, have jointly
published a booklet on their common policies and recommendations on low-frequency
electric and magnetic fields. The booklet is based on available scientific findings and
presents technical and economic aspects of possible countermeasures in the light of
limited community resources. The national authorities recommend a precautionary
principle primarily based on non-discountable cancer risks. No limit values ate specified.
The publication is intended for use as support in decision-making where different aspects
must be weighted in each individual case, balancing possible hazards against technical
and economic considerations.
5
HEMANGIOMA INPANTS
New research on the hemangioma infants
is published and discussed by Lundell, Holm
ami Lindell. Thyroid cancer has been
observed but no excess leukemia risk.
Uncertain Results from Epidemiological Studies
A large number of epidemiological studies are being performed in order to
establish whether there may be a connection between exposure to electric or
magnetic fields and an elevated risk of cancer. Where exposures in the
working environment are concerned, the main focus of attention has been on
the risks of certain forms of leukemia and brain tumour. For exposure in the
dwelling environment, the main concern has been with leukemia risks to
children. The results contain many points of uncertainty. For example,
different scientific reports indicate excess risks for completely different kinds
of cancer. Furthermore, there are no convincing and acceptable connections
between dose and the magnitude of risk. Experimental studies have so
10
THE CASE OP LINEARITY
The debate goes on with a letter from
Dr Rossi and Dr Webster and a
response from Bo Lindell.
13
continued on page z
far not yielded any results that clearly corroborate the epidemiological findings.
Several groups of experts have all come to the conclusion that exposure to low-
frequency magnetic fields cannot be convincingly shown to entail elevated risks of
cancer but that certain epidemiological studies provide some cause for suspecting
that there may be a connection with particular forms of cancer e.g. childhood
leukaemia.
The Precautionary Principle in Perspective
The debate regarding the health effects of work with computer displays (VDTs)
escalated during the first part of the 1980s and culminated in 1986-88. Despite
identified ergonomic problems, tbe discussion focused heavily on electric and
magnetic fields. SSI took the position that although mandatory regulations were
impossible, voluntary actions based on some principles of caution were highly
desirable. SSI laboratories took a leading position in the development of
instruments, test methods and standards. The response from both users and
manufacturers was immediate and overwhelmingly positive. The VDTs of today,
about ten years afterwards, have electric and magnetic field emissions which are
10-100 times lower than those of the 1980s without the regulating authorities
having issued any regulations and without any substantial increase in cost.
In the USA, researchers at Carnegie Mellon University, Pittsburg, have
formulated an approach to magnetic field problems which they have termed
"prudent avoidance". They argue that, as long as our knowledge of the connection
between health hazards and exposure remains incomplete, society cannot resort to
expensive, peremptory measures. On the other hand, given the reasonably strong
suspicion of detrimental effects to health, one should still take steps which do not
in themselves entail heavy expenditure or any other inconvenience. A similar
approach has been advocated, for example, in the preparatory work to the
Radiation Protection Act and the Health Protection Act. Already in 1993, the
Swedish Radiation Protection Institute published a policy document (I) on
magnetic fields along these lines. This was followed by an information brochure
intended for the public as a first result of an inter-authority collaboration.
Lars-Erik Paulsson,
Principal Scientist at the
Division of Non-ionising
Radiation at SS/.
published by:
SWEDISH RADIATION
PROTECTION INSTITUTE.
address:
SWEDISH RADI ATION
PROTECTION INSTITUTE (SSI)
S-Ill l6 STOCKHOLM
SWEDEN
TELEPHONE: +468 7297lOO.
TELEFAX: +468 7297I08.
editorial board:
LARS-ERIK HOLM, DIRECTOR-GENERAL
JOOST IlAYARDS, HEAD OF INFORMATION OFFICE AND
RESPONSIHLE IN ACCORDANCE WITH SWEDISH LAW.
LARS PERSSON, EDITOR [[email protected]]
IIJORN HOLM, EDITOR [[email protected]]
art director.
Criteria Group
There is a long tradition in Sweden of issuing mandatory regulations for identified
risk factors with regard to the occupational environment. The basis for these
regulations is developed by "Criteria Groups" established by the National Institute
of Working Life (formerly National Institute of Work, Environment and Health).
SSI has actively taken part in the group for physical risk factors. In 1995, a
working group presented a comprehensive report (2) on an evaluation of all the
epidemiological and experimental studies on cancer and low frequency fields. On
the basis of that report and supplemeiltary information, the Criteria Group issued a
new criteria document (3) in October 1995. The essence of the new document was
the conclusion that although the scientific database was insufficient for developing
limits of exposures this might not exclude other steps to reduce exposure, for
example some form of "strategy of caution".
After the release of the Criteria Group statement, the government authorities
declared that they would not issue mandatory regulations, but that they supported
the principles of a strategy of caution. In this situation, it is necessary that those
who must make decisions regarding planning, buildings and the installation of
equipment should be guided with regard to caution strategies. The five
aforementioned authorities have for that purpose agreed upon the present
document.MATERIAL IN THE SSI NEWS MAY
copyri!1U:
IIJORN HOLM, INFORMATION OFFICE.
BE USED FREELY WITH AN APPROPRIATE
National Authorities Recommend Caution
The national authorities have agreed to recommend the following precautionary
principle:
ACKNOWLEDGEMENT.
ISSN qoo-8 SI 3
2 SSI news No2, 1996
If measures to generally reduce exposure can be taken
at reasonable expense and with reasonable consequences in all
other respects, an effort should be made to
reduce fields radically deviating from that which can
be considered to be normal in the environment concerned.
Where new electrical installations and
buildings are concerned, efforts should be made, already at the
planning stage, to design and position
them in such a way that exposure is limited. The overriding purpose
of the precautionary principle is eventually to reduce exposure to
magnetic fields in our surroundings, so as to reduce the risk of
injury to human beings."
What Is a Normal Magnetic Field Level?
"The magnetic field level in the environment concerned" refers to
the magnetic field level in areas where human beings can he
expected to be repeatedly present for a considerable length of time,
for example, housing, schools, day nurseries and workplaces. The
"normal magnetic field level" refers to the average obtained, after
calculation or several measurements, for the magnetic field in the
surroundings concerned and in conditions which can be
representative for the field level over a long period. The median
value for homes and day nurseries in major towns or cities is
approximately 0.1 ~T (microtesla). The values in smaller towns and
rural areas are approximately half of this (4). Close to power lines
and transformer stations, the magnetic fields are higher. Right
underneath a power line, the figure can be about 10 ~T. It is
estimated that some 0.5 per cent of the housing stock has a
magnetic field exceeding 0.2 ~T, owing to the proximity of electric
installations of different kinds. In the working environment the
levels are higher and tend to fluctuate more. A median value of 0.2
~T was found for a large number of occupational categories in a
Swedish study. Levels of hundreds of ~T can occur briefly for
certain individuals or working situations with a daily average of
one or two ~T, for example, for welders.
SEK 7 million (Swedish road administration), cancer from ionizing
radiation SEK 12 million (the Nordic radiation protection
authorities), and lung cancer from radon in dwellings SEK 2
million (National Board of Health and Welfare). Similar figures
from the United States amount to between SEK 5 million and 50
million, with the nuclear power industry accounting for the highest
figures and the traffic sector accounting for the lowest ones. In
some of the areas mentioned above, the causal relationships have
been made clear, the risks are well known and the effects of
funding inputs are calculable or quantifiable. It is, however, quite
easy to imagine an "imprudent - prudent avoidance" way of acting.
Examples of Cost Estimates
On average in Sweden and in most other industrialized countries,
one child in 25,000 per annum develops leukemia. Although the
hypothesis of the connection between the occurrence of child
leukemia and exposure to magnetic fields cannot be deemed to be
scientifically established, the observed risks can be used when
estimating an upper boundary for the cost to eliminate exposure. In
one of the Swedish epidemiological studies, it was observed that
children living close to power transmission lines ran a 2.7 higher
risk of developing leukemia than those living far away from such
transmission lines. This figure has also been applied to transformer
stations and stray currents in the following examples, for lack of
other risk estimates. We also assume a technical/economic lifetime
of 40 years for the measure taken and an interest rate of 4 per cent.
On these assumptions, it can be shown that the cost per statistical
case avoided will be R=735 K/N [SEK/case), where K is the cost
of the measure taken and N the number of individuals whose
exposure the measure eliminates.
It has to be noted that our examples ate only intended to
illustrate a calculation model fot arriving at a comparison between
different costs. Depending on the circumstances of the individual
case, there may be other solutions or bases for economic
calculation which are more appropriate. The calculation model
only deals with statistical cases, and many people will have to
derive benefit from a measure in order for public health to be
influenced.
What Is "Reasonable Expense"?
Human life cannot be valued in terms of money, but even so, it will
be readily understood that there are many situations where the
possibility for society or individuals to save lives or avert serious
illnesses is limited by the lack of
resources. Constraints on
resources are an inescapable
fact and do not reflect any
desire to put a price tag on
people's lives.
The amount which society is
ready to pay in order to save a
"statistical life" varies a great
deal from one sector of
society to another and from
one risk factor to another.
Some
benchmarks for expenditure
per fatality/casualty avoided
can be found in other areas, for
example death from road
accidents
Examples
,. Power Line Near to Multi-family Dwellings
An existing 220 kV power transmission line crosses a multifamily
housing area with 3°0 children living within a distance of the line
where the risk of child leukemia is presumed to increase through
proximity to the power line. The cost of replacing the power line
with another solution - a cable along an existing road - is SEK 60
million. If this measure is taken, the cost per case avoided, assuming
the estimated risk to he true, will be about SEK 15° million.
Calculations by local authorities may involve other aspects on
which a value can be placed, e.g. the fact of land being released for
alternative use.
SS! news No2, 1996 3
A transformer station in a school building causes elevated magnetic fields in three
classrooms. One possible means of reducing the magnetic fields is to line the area
with sheet metal. A measure of this kind costs about SEK 1,000/m2, materials and
labour included, which can mean a total cost of about SEK 200,000. Assuming
that the measure will reduce the exposure for 75 children, the cost per case
avoided will be less than SEK 2 million.
2. Transformer Station in a School Building The Development
of New Ideas in Physics
Dr Nils Ryde, Professor Emeritus, Department of
Physics, Chalmers University of Technology,
Gothenburg, Sweden has written a book which is
of interest to radiation protection specialists with
a background in physics, Professor Ryde has
played an important role in the development of
several areas of experimental physics. Professor
Ryde and his research team have studied, among
other things, the fission process and non-des-
tructive methods to measure the degree of burnup
of spent nuclear fuel. This work was supported
by the IAEA.
The new book (196 pages) is entitled
"Development of Ideas in Physics" and is
published by Almqvist and Wiksell International,
Stockholm, Sweden. The content covers atoms,
optical spectroscopy, X-ray spectroscopy,
quantum mechanics, neutron physics, atomic
models, neutrino physics, spinning particles,
fission as well as the origin of elements and anti-
matter. I warmly recommend this book for
reference collections in physics.
3. Stray Currents in Single-family Dwellings
A single-family dwelling has elevated magnetic fields which are caused by stray
currents in water pipes and electrical lines in the house. The cost to eliminate
these currents will be SEK 5,000. Assuming that there will be, on average, one
child living in the home over a period of 40 years, the cost per statistical case
avoided would be about SEK 4 million.
A 400 k V power transmission line is planned in a rural area. An effort has been
made at the planning stage to locate the line as favourably as possible, fo
4. Power Line in Rural Area
r
example from the viewpoint of persons living close by. It is intended to use a
power line structure, a T-pole, which is more advantageous from the viewpoint of
the magnetic field than the traditional transmission line strucrure. These measures
can be taken without any appreciable added expense or other consequences.
Even so, for 80 kilometres of its length, the line will pass within such a distance
of 71 scattered properties that the magnetic fields in the properties can be
considered to be increased. With a view to reducing the fields locally on each
property, the possibility is being investigated of using tuned screened circuits.
Every such circuit costs an estimated SEK 0.5 million. Assuming that, on
average, there is one child living on each property and there are no other
economic aspects to be taken into consideration, the cost per case avoided will be
about SEK 370 million. The cost per case will be the same if it is decided to
purchase the properties for an average of SEK 0.5 million each.
LARS PERSSON
Information Office
Irradiated Spices for
Sale in Sweden?
Conclusions
The precautionary principle recommends that measures should be considered
when the fields deviate strongly from what can be considered to be normal in the
environment concerned. The examples show that exposure reduction measures
can cost from a couple of million to several hundred million Swedish kronor per
statistical case of child leukemia avoided, provided that the risk estimates are
valid. It is obvious that the higher figures largely exceed what has normally been
spent for the reduction of similar risks in other areas. In the light of the large
uncertainties involved in this case, only the lower figures will probably be
considered realistic. The introduction of economic concepts will hopefully
provide a better basis for optimized political decisions.
In the 1997 budget proposal published recently,
the Swedish government declares that the
irradiation of spices and the import of already
irradiated spices should be permitted in Sweden
in the future. If this proposal is accepted by the
Swedish parliament, the absolute ban on all
irradiation of foodstuffs which currently exists
will be relaxed.
The European Community has banned the use
of ethylene oxide to kill pathogenic bacteria in
spices. Irradiation is currently the only
reasonable alternative to ethylene oxide.
However the irradiation of foodsruffs is a very
controversial political issue in Sweden. The fact
that the opponents of irradiation are not in favour
of the use of chemicals either makes the situation
even more bizarre. The opponents assert that the
only acceptable alternative is to promote more
hygienic handling and storage conditions in the
spice-producing countries.
JjONAS
KARLBERG X -rays and Radioactive
Substances
LARS-ERIK PAULSSON
Principal Scientist; Division of Non-ionising Radiation
This paper Includes several edited citations from the original booklet. Readers
interested in the full text can obtain a copy from 551. see page 15.
References
I. Kivisakk E.. Moberg l. "551 policy: Health risks from electromagnetic fields".
551 News No 2. February, 1993.
2. Hardel! L.. Holmberg B.. Malker H., Paulsson L-E.: "Exposure to extremely low frequency
electromagnetic fields and the risk of malignant diseases - an evaluation of epidemiological
and experimental findings", European J Cancer Prev, vol 4 (supplement I): 3-107 (1995).
3. The Criteria Group for Physical Risk Factors. Magnetic fields and cancer
- a criteria document. Arbete och Hatsa 1995: 13, pp 1-10. (in Swedish with English abstract)
4. Nissen J., Paulsson L-E.: "Magnetic fields in Swedish residences and day nurseries." in Supplement
from EMC-Zurich Electromagnetic Compatibility 1995, 11th International Zurich Symposium and
Technical Exhibition on Electromagnetic Compatibility 7-9 March, 1995, Zurich, p 139-143.
4 SSI news N02, 1996
103E L E C T R O P O L L U T I O NENVIRONMENT UNDER PRESSURE
Some people lay metal mats under their beds to neutralize the effects of electromagnetic fields
(EMFs), while others put their faith in glass pyramids. There are even people who sleep in a different
place every night – all for fear of “electropollution” (or “electrosmog”, as it is commonly known in
Switzerland). The reason for this concern is the unprecedented increase that has occurred in recent
years in the number and variety of EMF sources, whether from personal appliance use or from
commercial and industrial applications.
SLEEPLESS IN A SEA OF RADIATION?
There can be no doubting the fact that we are today surrounded by electromagnetic radiation.The culprits are mobile-telephone transmitters(known as “base stations”) and the mobile phonesthemselves, cordless telephones, radio and tele-vision transmitters, power lines, computers, radar,microwave ovens and equipment used in industryand medicine. Electropollution – or non-ionizingradiation (NIR), to give this phenomenon its cor-rect name – includes all forms of radiation which(in contrast to ionizing, radioactive radiation) donot have sufficient energy to modify atoms andmolecules. NIR occurs as an unwanted by-productaround electrical installations such as power linesand transformers and around electrical equipmentfor the home and office. In the case of transmit-ters and mobile phones, on the other hand, the
104SA
EFL
– EN
VIRO
NMEN
T S
WIT
ZERL
AND
2002
1 Hz 1 MHz1 kHz 1 GHz
HIGH FREQUENCYLOW FREQUENCY
Source: SAEFL
radiation actually provides the vehiclefor the transmission of information andis therefore technically unavoidable.
But it is precisely the erection of mo-bile telephone antennas in residentialareas that is arousing public anxietiesand protests. The opposition is mo-tivated both by a desire to protect thelandscape and by medical concerns.While on the one hand antennas can bea major blot on the landscape, there arealso growing fears among the popu-lation that the explosive growth inmultimedia communication and theattendant increase in electromagneticradiation could cause serious damageto health. It is unclear, however, quitehow many people blame mobile tele-phone antennas for physical ailments.What we do know is that over half ofthe population of Switzerland use mo-bile phones – and thousands of newsubscribers are joining them every day.
The same applies to projects involv-ing high-voltage power lines – only here the situation is aggravated by thefact that once such installations havebeen built, they will generally occupythe same corridor for decades to come.Electropollution is therefore a socio-political issue that is provoking pro-found controversy.
This is by no means an easy topic todeal with – probably because the scien-tific basis for this environmental phe-nomenon is not immediately apparent.
The Swiss “Ordinance relating to Protection from Non-Ionizing Radiation” (ONIR) con-
tains two types of limit values: exposure limit values and precautionary limit values.
Exposure limit valuesExposure limit values afford protection against scientifically established adverse health
effects. They take into account the total radiation that is present at a particular loca-
tion. They must be complied with in any location to which individuals might possibly
have access (even for short periods). Exposure limit values are internationally agreed
and compliance will not usually pose any problems in Switzerland.
Precautionary (installation) limit valuesThe precautionary principle, as enshrined in the Environmental Protection Law, dic-
tates that exposure must be low – in fact, it must be as low as is technically and oper-
ationally possible and economically acceptable. Installation limit values are substantially
lower than the exposure limit values. They apply to the radiation from a single instal-
lation and must be observed in locations where individuals spend prolonged periods
(e.g. homes, schools, hospitals). The installation limit value is fixed in accordance with
the technical possibilities afforded by the type of installation in question.
Exposure limit values for the frequency ranges of selected installations:Instal lat ion Exposure l imit value
Railways 16 2/3 Hz 300 µT; 10 000 V/m
High-voltage power lines 50 Hz 100 µT; 5 000 V/m
Radio broadcasting
transmitters 10-400 MHz 28 V/m
Mobile telephone 900 MHz 41 V/m
base stations 1800 MHz 58 V/m
UMTS base stations 2100 MHz 61 V/m
Installation limit values within the frequency ranges of selected installations:Instal lat ion Instal lat ion l imit value
Railways 1µT (24 hr mean)
High-voltage power lines 1 µT
Radio broadcasting transmitters 3 V/m
Mobile telephone 900 MHz 4 V/m
base stations 1800 MHz 6 V/m
UMTS base stations 2100 MHz 6 V/m
ONIR: Two l imit values – two terms
105E L E C T R O P O L L U T I O N
ENVIRONMENT UNDER PRESSURE
DIFFERENT APPROACHES TO LIMIT SETTINGThe setting of protection limits is based both on the published scientific studies and on
general experience of the biological effects of electropollution. However, one cannot
simply translate these findings directly into limit values without first subjecting them to a
process of evaluation. For example, it is necessary to decide whether a study has been
carried out in accordance with recognized scientific principles and is thus reliable, and
furthermore whether any identified effect is significant with respect to human health. This
evaluation is undertaken by specialists in the fields of biology, medicine and toxicology.
The conclusions reached by these review bodies and the exposure limits that are set
will vary according to the criteria applied and what degree of protection they are seeking
to achieve. Outlined below are two different ways of tackling this evaluation process.
Finally, a third approach is presented which is based not on biological effects, but on
the technical possibilities that exist for reducing electropollution.
The ICNIRP hazard reference levels. The International Commission on Non-Ionizing
Radiation Protection (ICNIRP) is a private, non-governmental organization which in 1998
published Guidelines on Limiting Exposure to EMFs. In formulating these guidelines, it
took into account only the biological effects which had repeatedly and reproducibly
been demonstrated in experimental research and which clearly pose a human health
hazard. In the view of the ICNIRP, the following are the only health effects that satisfy
this criterion:
• in the low-frequency range (electricity supply, railways): involuntary contraction of
muscles and disrupted nerve cell firing patterns; and
• in the high-frequency range (transmitter installations): excessive increases in body
temperature.
These are considered to be acute effects. Other effects for which a risk to health is not
clearly discernible, single observations and non-reproducible results were not taken into ac-
count when the ICNIRP limit values were set, nor were epidemiological studies considered.
Although the Commission did incorporate a safety factor when deriving its limit
values, this applies only to those particular effects that featured in its deliberations. The
ICNIRP limits are therefore limit values for protection against known hazards and not
precautionary limit values. As far as mobile telecommunications is concerned, they
relate exclusively to thermal effects.
Compliance with the ICNIRP exposure limits will certainly protect human beings
against the acute effects specified above. Given the limited nature of the data that were
used in deriving the ICNIRP limits and in view of experimental and epidemiological re-
search findings suggestive of athermal effects, it is questionable, however, whether pro-
tection is also afforded against other effects, and in particular against long-term effects.
The “Salzburg Resolution”. A different approach to the establishment of exposure
limits is followed by the so-called “Salzburg Resolution”. At an international conference
held in Salzburg in June 2000, critical scientists and representatives of the public
health authorities were afforded their first opportunity to meet at international level.
They discussed the current state of knowledge regarding exposure and the health
effects of high-frequency electromagnetic fields, addressing these topics both from a
public health standpoint and in the light of the precautionary principle. In assessing the
problems involved, they also took into account scientific findings that tend to suggest
a risk to health, but do not as yet furnish any definitive evidence. High priority was
accorded to epidemiological studies, since investigations of this kind focus on actual,
everyday situations involving human exposure.
The upshot of these deliberations is the “Salzburg Resolution on Mobile Telecommu-
nication Base Stations”. The signatories to the Resolution conclude that there is cur-
rently evidence to suggest that even extremely low levels of radiation could have adversecontinued on p. 106
Radiation is, after all, something thatwe can neither hear, feel nor smell.While we may perhaps feel its effects,we would need to explore some highlycomplex areas of physics and medicinein order to investigate the underlyingcauses.
Moreover, there is still great uncer-tainty in the scientific community overthe possible effects of non-ionizingradiation on health. In the case of ex-posure to high levels of radiation, theharmful effects are both proven andacknowledged. As regards low-level ex-posure, however, the picture is lessclear. Although biological effects havebeen demonstrated in the laboratory,the scientists are still arguing overwhether or not these are harmful. Stat-istical comparisons have been madebetween population groups subjectedto high and low levels of exposure. Thefindings of such studies are contradic-tory. In some cases, an increased risk ofdiseases such as leukaemia or sleep disorders is discovered, whereas otherstudies show nothing untoward. Whatknowledge we do have can be likenedto a jigsaw puzzle for which all but afew pieces are missing and no coherentexplanation has been advanced.
The fact that even the scientists can-not agree over the significance of theirfindings merely fuels the disputes thatare raging between operators and criti-
continued on p. 107
106SA
EFL
– EN
VIRO
NMEN
T S
WIT
ZERL
AND
2002
An illustration of electromagnetic radiation in the vicinity of a high-power mobile-telephone base station mounted on a flat-roofed building. The antenna “focuses” theradiation in a similar way to a car headlamp and steers it in the required directions. In the area shaded black, the exposure limit value is exceeded. Entry to this area isprohibited – even for short periods. Inside the area shaded pink, the installation limit value is exceeded. No facilities classified in the ONIR as “places of sensitive use”(homes, schools, hospitals, offices, children's playgrounds, etc.) may be sited within this area. In the blue and white area, the installation limit value is complied with – andthe same applies inside the building, since the concrete roof attenuates the level of radiation. The additional lines indicating levels of twice and half the installation limitvalue serve to illustrate how radiation diminishes as the distance and deviation from the direction of maximum radiation increase. The intensity of radiation in the white areaamounts to less than one eighth of the installation limit value.
Radiat ion near a mobi le-telephone base stat ion
–10 0 10 20 30 40 50 60 70 80 90 100
60
50
40
30
20
10
0
effects on health and therefore that a zero-effect threshold does not
exist. Recommendations of specific limit values are therefore prone
to considerable uncertainties – they contend – and should be con-
sidered preliminary. Despite this difficulty, the Resolution does
recommend a precautionary limit value for radiation from mobile
telecommunications equipment. This is around 100 times lower
than the ICNIRP's “thermal” exposure limit. The Salzburg limit
value is a biologically based precautionary limit value founded on
the rationale that biological effects do exist in the presence of low-
level radiation. While it is uncertain whether these effects are,
indeed, harmful, the fact remains that they could very well be. As
a precaution, therefore, exposure to radiation should remain below
these “suspected effect” thresholds.
Avoidable exposures are to be avoided. The third approach is
based not on biological effect thresholds, but on the technical pos-
sibilities that exist for reducing radiation. In the Swiss Environmen-
tal Protection Law, for example, it is stipulated that radiation must,
as a precautionary measure, be limited to the maximum extent
that is both technically and operationally possible, and economic-
ally acceptable. Experience tells us that exposure to electropollution
can, in most cases, be kept far below the ICNIRP hazard reference
levels at an affordable cost, especially in places where individuals
spend prolonged periods. This experience can likewise be trans-
lated into limit values, which in this particular case will be precau-
tionary limit values based on technical and economic consider-
ations.
The decision as to which approach is to be followed in setting
exposure limits is based not on science but on political consider-
ations. Essentially, it hinges on what degree of protection is being
sought. Above all, the politicians will have to answer the question
of how they propose to deal with those risks that are classified as
being either “uncertain” or “questionable”. This question assumes
particular importance in such areas as mobile telecommunica-
tions, where virtually the entire population is exposed to this form
of radiation.
In the Ordinance relating to Protection from Non-Ionizing Radi-
ation, the Federal Council has opted for the following approach:
• To afford protection against proven damage, it has adopted the
ICNIRP's hazard reference levels.
• As far as potentially harmful effects are concerned, it has taken
the precautionary step of setting installation limit values based
on technical and economical considerations.
Metres
Metres
D i r e c t i o n o f m a x i m u m r a d i a t i o n
Instal lat ion l imit value
0.5x the instal lat ion l imit value
Exposure l imit value
2x the instal lat ionl imit value
107E L E C T R O P O L L U T I O N
ENVIRONMENT UNDER PRESSURE
cal pressure groups. The industry isdemanding proof of harmful effects be-fore it will take steps to limit exposure.Environmental organizations, certainmedical practitioners and members ofthe public, on the other hand, object tothe public being used as guinea pigs.They are demanding that a new techno-logy should be proven not to be harm-ful before it is introduced.
Uncertainty is no excuse for inactivity. Inspite of all the uncertainty, limits needto be imposed without delay. Becauseone thing is absolutely clear: exposureto radiation will continue to increase. Itis now a matter of establishing what ex-posures are acceptable and what arenot. The Federal Council has alreadyresponded by issuing exposure limitsfor proven damage and precautionaryvalues for potentially harmful effects.In doing so it fulfilled its mandateunder the Environmental ProtectionLaw (USG), which stipulates that elec-tropollution must, as a precautionarymeasure, be limited to the maximumextent that is technically and economic-ally feasible, but at least to such an ex-tent that it is neither harmful nor cons-titutes a nuisance to human beings.
The “Ordinance relating to Protec-tion from Non-Ionizing Radiation(ONIR)” came into force on 1 February2000 and is considered to be among themost stringent regulations of its kind inEurope.
The ONIR contains two types oflimit values. The first are the so-calledinstallation limit values, which aim toplace a precautionary ceiling on radi-ation emissions from a particular instal-lation. Secondly there are the exposurelimit values, which are based on in-ternationally recognized, scientificallyverified recommendations.
However, the Ordinance does notonly contain regulations governing in-stallations that produce electropollution,but also provisions relating to spatialplanning. In future, new building zonesmay only be designated in locationswhere the installation limit value is notexceeded.
Government supports product labelling.Mobile phones are neither covered bythe Environmental Protection Law norby the ONIR. The limitation of radi-ation from mobile phones and otherelectrical appliances requires inter-national technical regulations, whichSwitzerland cannot issue unilaterally.One effective way of motivating pro-ducers to develop low-emission appli-ances and to inform consumers aboutthe degree of exposure from theirmobile phones is for them to declareemissions. The federal government sup-ports the efforts of the consumer organ-izations to bring about the introductionof such product labelling.
OUTLOOKExposure to non-ionizing radiation willcontinue to increase – as will the var-iety of EMF sources – owing to the
Mobile telephones emit electromagnetic waves at frequencies of 900 or 1800 MHz. The radiation there-fore lies in the microwave range, which can cause heating of body tissue. The internationally recom-mended exposure limits for mobile phones are basedon this thermal effect. Even if the thermal exposure limits are complied with, so-called athermal effectscan occur inside the head of the mobile phone user.Intensive research is currently underway to establish whether these phenomena have a detrimental effecton health. The key question is whether radiation frommobile phones promotes the development of brain tumours.
countless new technologies that are setto arrive on the market over the nextfew years.
The principle to be adopted in devel-oping new technologies must thereforebe that radiation should be kept to aminimum. Ideally, health risks will infuture be identified before new appli-cations are introduced. This requires athorough understanding of the possibleeffects of NIR on the human body.Such knowledge will, of course, taketime to accumulate.
Even if our level of knowledge doesimprove, there is no such thing as zerorisk – nor has there ever been through-out the entire history of industrial-ization. Because we shall thereforealways be left with a “residual risk”,new technologies must be monitoredafter their introduction by means of ap-propriate research programmes. ■
Radiat ion threat to mobi le phone users?
Use
ICNIRP Statement
USE OF THE ICNIRP EMF GUIDELINES
(March 31, 1999)
Introduction and purpose
Since the publication of the ICNIRP guidelines for limiting EMF exposure up to 300 GHz1) several institutions have criticized the guidelines as lacking clear interpretation on exposure safety or direct application to equipment in existence. Concerns have also been expressed about the use of safety factors, precautionary aspects and long term exposure as well as points not included in the ICNIRP guidelines. This STATEMENT from the International Commission on Non-Ionizing Radiation Protection (ICNIRP) addresses these concerns and clarifies points such as the criteria used for evaluating scientific studies, the development and practical application of the guidelines, the need for special technical advice, how to consider social and economic aspects and how to handle current research. This statement clarifies the way in which the guidelines should be used in a regulatory and legislative context. Some questions have already been addressed by publications in Health Physics.2)
Quality criteria for evaluating scientific studiesDevelopment of guidelines on exposure limits requires a critical, in-depth evaluation of the established scientific literature using internationally accepted quality criteria. Experimental results can only be accepted for health risk assessment if a complete description of the experimental technique and dosimetry are provided, all data are fully analyzed and completely objective, results show a high level of statistical significance, are quantifiable and susceptible to independent confirmation, and the same effects can be reproduced by independent laboratories.3) When evaluating epidemiological studies, quality criteria are based on the need to evaluate, reduce or adjust for the influence of chance, bias and confounding. Cases of disease should be identified independent of exposure, and exposure should be assessed in a way not related to disease status. The influence of other variables should be handled in the design or in the analysis of the study. Any data on which the conclusions are based should be reported.4) The final overall evaluation of the evidence should include the assessment of the strength and consistency of the association between EMF exposure and biological effects from both epidemiological and experimental studies, as well as the plausibility that biological systems exposed to EMF fields could likely manifest biological effects. It is also necessary to identify which EMF-induced biological effects are to be considered a hazard to the human health.
The role of ICNIRPInternational recommendations of health-based guidance to limit exposure require an assessment of possible adverse health effects using established scientific and medical knowledge. This must be based mainly on the science and should be free of vested interest. ICNIRP, as an independent scientific body comprising all essential scientific disciplines, is qualified to carry out the task of assessing possible adverse health effects, together with WHO. ICNIRP is the formally recognized non-governmental
http://www.icnirp.de/documents/Use.htm (1 of 5) [03.Jun.05 8:58:11 AM]
Use
organization in NIR protection for the WHO, the International Labour Organization (ILO), and the European Union (EU) and maintains a close liaison and working relationship with these international bodies as well as IEC and CIE for the optical region and with other bodies engaged in NIR protection. ICNIRP's review process includes Standing Committees and additional experts. The consultation process is extensive and includes IRPA national bodies and other independent scientists and organizations worldwide. ICNIRP works in conjunction with the WHO to assess health effects of exposure to NIR, which are published in the WHO Environmental Health Criteria monographs, and uses the results of this assessment to draft health-based exposure guidelines.
Developing of exposure guidelinesRecently the ICNIRP adopted guidelines on limits of EMF exposure for frequencies up to 300 GHz.1)
While all the scientific literature was reviewed, the only adverse effects on humans that were fully verified by a stringent evaluation were short term, immediate health consequences such as stimulation of peripheral nerves and muscles, functional changes in the nervous system and other tissues, shocks and burns caused by touching conducting objects, and changes in behavior caused by elevated tissue temperatures. There are also data for chronic low level exposure that indicate that there may also be other health effects. It is, however, ICNIRP's view that in the absence of support from laboratory studies the epidemiological data are insufficient to allow an exposure guideline to be established. Limiting values are given as basic restrictions and reference levels. Basic restrictions directly relate to established health effects. Appropriate safety factors are included. Reference levels are derived from the basic restrictions for worst-case exposure situations and are in quantities that can be easily measured. They provide levels that can be used to determine compliance with the basic restrictions. By using the system of basic restrictions and derived reference levels, the new ICNIRP guidelines offer flexibility for many exposure situations.
The use of safety factorsIt is ICNIRP's view that safety factors in the ICNIRP EMF guidelines should relate to the precision of science, reflecting the amount of established information on biological and health effects of EMF exposure. Numerically uncertain relationships between established effects and exposure levels result in higher safety factors and vice versa. As with the assessment of adverse health effects, setting safety factors should be free from vested interests. There is no rigorous basis for determining precise safety factors. Safety factors are based on a conservative value judgment by experts. In the new ICNIRP guidelines the safety factors vary from approximately 2 to > 10 (see next section) depending upon the extent of uncertainty in knowledge of thresholds for health effects for direct and indirect field interaction at various frequencies. For the purpose of defining guidelines for protection, a simplified and conservative approximation of the frequency dependence of biological effects was chosen. In general, threshold field levels for indirect effects (e.g., response to contact currents) are better defined than for direct effects, and hence, less conservative safety factors are required.Public guidelines include additional safety factors of 2 to 5 relative to occupational guidelines (depending upon the frequency and the relevant dosimetric parameters). Occupational health standards are aimed at protecting healthy adults exposed as a necessary part of their work, who are aware of the occupational risk and who are likely to be subject to medical surveillance. General population guidelines must be based on broader considerations, including health status, special sensitivities, possible effects on the
http://www.icnirp.de/documents/Use.htm (2 of 5) [03.Jun.05 8:58:11 AM]