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Electric and Magnetic Fields FAQs

Where does EMF come from?

Power frequency (also referred to as extremely low frequency or ELF) electric and magnetic fields are present everywhere that electricity flows. All electrical wires and the lighting, appliances and other electrical devices they supply are sources of electric and magnetic fields. Although they are often referred to together as EMF, electric fields and magnetic fields are actually distinct components of electricity.

Most of the interest regarding possible health effects is related to magnetic fields. So usually, when the term EMF level is used, it is the magnetic field strength that is being referred to or measured.

How much EMF does a power line give off?

All overhead and underground power lines produce electric and magnetic fields. EMF is dependent upon line voltage, loads and current in a power line. The fields are highest directly under/over the power line and quickly become weaker as one moves away from the centreline. The field levels are dependent on a number of factors, so if it is difficult to give one typical level. If you would like information about a specific power line, please contact your local electrical utility.

How concerned should people be about living around power lines?

Health Canada’s It’s Your Health fact sheet on EMF states, “Health Canada does not consider guidelines [on EMF exposure levels] necessary because scientific evidence is not strong enough to conclude that exposures cause health problems for the public.”

Health Canada goes on to state, “You do not need to take action regarding daily exposures to electric and magnetic fields at extremely low frequencies.”

Further information can be found here:
Health Canada Link

Are there regulated EMF exposure guidelines?

In Canada, there are no guidelines or standards on acceptable levels of residential EMF exposure. Health Canada’s It’s Your Health fact sheet on EMF states, “Health Canada does not consider guidelines [on EMF exposure levels] necessary because scientific evidence is not strong enough to conclude that exposures cause health problems for the public.”

Please go to:
Health Canada Link

What is Health Canada’s position on EMF exposure?

Health Canada, along with the World Health Organization, reviews scientific research on EMFs and human health as part of its mission to help Canadians maintain and improve their health. At present, there are no Canadian government guidelines for exposure to EMFs at low frequencies.

Health Canada’s It’s Your Health fact sheet on EMF states, “Health Canada does not consider guidelines [on EMF exposure levels] necessary because scientific evidence is not strong enough to conclude that exposures cause health problems for the public.” Health Canada goes on to state, “You do not need to take action regarding daily exposures to electric and magnetic fields at extremely low frequencies.”

Please go to:
Health Canada Link

What does WHO have to say about EMF?

In 2007 The World Health Organization (WHO) published Environmental Health Criteria 238 (2007): Extremely Low Frequency (ELF) Fields.

Publications Link

An excerpt from the document follows (see Section 1.1.12 from Summary and Recommendations). Please note that WHO separately addresses “acute” effects and “chronic” effects by definition acute effects have no adverse health implications.

“It is essential that exposure limits be implemented in order to protect against the established adverse effects of exposure to ELF electric and magnetic fields. These exposure limits should be based on a thorough examination of all the relevant scientific evidence. Only the acute effects have been established and there are two international exposure limit guidelines (ICNIRP, 1998a; IEEE, 2002) designed to protect against these effects. As well as these established acute effects, there are uncertainties about the existence of chronic effects, because of the limited evidence for a link between exposure to ELF magnetic fields and childhood leukaemia. Therefore the use of precautionary approaches is warranted. However, it is not recommended that the limit values in exposure guidelines be reduced to some arbitrary level in the name of precaution. Such practice undermines the scientific foundation on which the limits are based and is likely to be an expensive and not necessarily effective way of providing protection.”

Is EMF the same as radiation?

When radiation is used in a health context, generally they are referring to ionizing radiation or to RF radiation and not EMF. X-rays, visible light, radio waves, microwaves and power frequency EMF are all forms of electromagnetic energy making up an electromagnetic spectrum. One property that distinguishes different forms of electromagnetic energy is the frequency, measured in hertz (Hz). Power frequency EMF has a frequency of 60 Hz. It is near the lowest end of the spectrum and well below the microwave or RF (radio frequency) radiation emitted by cellular phones and radio broadcast transmitters (up to 1900 MHz). Unlike x-rays and gamma rays (1016 Hz), power frequency EMF has little energy and no ionizing or thermal effects on the body. (Note: 1 MHz = 1 million Hz)

What does the latest research say about the link between EMF exposure and childhood cancers?

A number of EMF research reports are issued every year. Individual reports may point in different directions, however there are national and international agencies that review and analyze the current studies to arrive at an overall conclusion regarding the science evidence.

In 2007 The World Health Organization (WHO) published Environmental Health Criteria 238 (2007): Extremely Low Frequency (ELF) Fields. Please see the separate FAQ on the WHO. In Canada, as well as Health Canada, the Federal Provincial Territorial Radiation Protection Committee (FPTRPC), a grouping of health agencies from across the country, monitors research and publishes summary opinions.

Their most recent Response Statement was published on November 8, 2008.

Link:
Health Canada Response Statement


The National Institute for Environmental Health Science has made similar statements: For the NIEHS documents, see: National Institute Link

In 2002, after an evaluation of the scientific data, the International Agency for Research on Cancer (IARC) classified ELF magnetic fields as “possibly carcinogenic” to humans based on studies of childhood cancer.

Link: Monographs

The basis for the IARC classification is the continuing unexplained association between magnetic field exposures and childhood leukemia. No evidence was found between other types of childhood cancers or adult cancers. That is why the classification is “possible” and not the more definitive “probable”. More studies are needed to draw firm conclusions.

Also the WHO EMF project has a fact sheet on cancer where the IARC classification is explained:
Fact Sheets Link

What kind of research is being done in Canada to determine the effects of overhead lines and EMF on our health?

While Canadian health organizations and utilities have in the past been involved in significant research projects regarding EMF and human health, there are no major projects taking place at this time. However Health Canada continues to monitor scientific research on EMF and human health as part of its mission to help Canadians maintain and improve their health.

Is there a safe level of EMF?

Health Canada’s It’s Your Health fact sheet on EMF states, "At present, there are no Canadian government guidelines for exposure to EMFs at ELF. Health Canada does not consider guidelines for the Canadian public necessary because the scientific evidence is not strong enough to conclude that exposures cause health problems for the public". Health Canada goes on to state, “You do not need to take action regarding daily exposures to electric and magnetic fields at extremely low frequencies.”
 
For further information:
Health Canada Link

Does the earth produce EMF?

Yes, electric fields are produced by atmospheric conditions including air turbulence and thunderstorms. Magnetic fields of strengths up to 500 mG are probably the result of electric currents within the earth's molten core. However, since these are DC or static fields, their potential interaction with the human body would be different.

Guidelines have been developed for occupational exposure to EMF. Health Canada’s Its Your Health fact sheet notes that “These guidelines are not based on a consideration of risks related to cancer.

Rather the point of these guidelines is to make certain that exposures to EMF do not cause electric currents or fields in the body that are stronger than the ones produced naturally by the brain, nerves and heart.” Guidelines have also been developed for implanted medical devices.

Typical public exposures fall well below these levels.

What is the EMF from power lines like when compared to the EMF from household appliances?

The EMF from power and transmission lines fall in the same category as the EMF we are exposed to from household wiring, fluorescent lighting, hair dryers and computers. They all fall in the category of extremely low frequencies.

Link to Household EMF

How strong is the EMF from electric power substations?

Beyond the substation fence, the EMF produced by the equipment within the station are typically indistinguishable from background levels. Generally, the strongest EMF around the outside of a substation come from the power lines entering and leaving the station. The strength of the EMF from transformers decreases rapidly with increasing distance.

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