EMF and Health

“EMF” is an abbreviation for “electric and magnetic fields” and “electromagnetic fields”

Current evidence does not confirm the existence of any health consequences from exposure to low level electromagnetic fields.

What is EMF?

“EMF” is an abbreviation for “electric and magnetic fields” and “electromagnetic fields.” Power lines, appliances, and home wiring all produce electric and magnetic fields. “EMF” is also often used by people as shorthand for just “magnetic fields,” which some people are concerned about, so that is what “EMF” refers to here. Download the PPL EMF Fact Sheet.

What are the EMF levels from common sources?

Examples of EMF Sources*
(in milligauss)
Coffee makers 7
Distribution line upper level of typical average 20
Dishwashers 20
500 kV transmission line typical average at edge of right-of-way 30
Distribution line typical maximum above underground 40
Florescent lights 40
Distribution line typical maximum under overhead line 70
Blenders 70
500 kV transmission line typical average under the line 87
Toasters 100
Hair dryers 300
Can openers 600

*People typically change activities and locations during a day, so we are exposed to a variety of sources of EMF and a wide range of field levels. In the table above, field levels are taken from the U.S. National Institute of Environmental Health Sciences (NIEHS) EMF Questions & Answers, pages 33-35 (median level at 6 inches from appliances), page 36 (distribution lines), and page 37 (transmission lines). As noted by NIEHS, field levels of transmission lines can approximately double during peak loads, which occur about 1% of the time.

Is EMF "radiation" like medical X-rays or ultraviolet sunlight?

No. Radiation from medical X-rays and from the ultraviolet part of sunlight is strong enough to damage DNA, but EMF from power lines, appliances, and home wiring is not. (See page 3 for more information.)

What does the World Health Organization say about whether EMF causes health effects?

The World Health Organization says on its website: Based on a recent in-depth review of the scientific literature, the WHO concluded that current evidence does not confirm the existence of any health consequences from exposure to low level electromagnetic fields.

(http://www.who.int/peh-emf/about/WhatisEMF/en/index1.html, section 2, “Conclusions from scientific research.”)

Are there any EMF exposure guidelines?

Yes. Two international expert groups have issued exposure guidelines based on avoiding very high levels of exposure that can produce short-term biological responses, such as the perception of a faint flickering of light or a tingling on the skin. The international expert groups are the Institute of Electrical and Electronics Engineers (IEEE) and the International Commission on Non-Ionizing Radiation Protection (ICNIRP).

Both groups of experts have concluded that no adverse health effects occur at EMF levels below their exposure guidelines.

EMF levels under a typical 500 kV high voltage transmission line are 95% below the strictest guideline.

Typical EMF Levels from Power Lines* compared to EMF Exposure Guidelines (in milligauss)
IEEE exposure guideline for general public 9,000
ICNIRP exposure guideline for general public 2,000
500 kV transmission line typical average under the line 87
Distribution line typical maximum under overhead line 70
Distribution line typical maximum above underground line 40
500 kV transmission line typical average at edge of right-of-way 30
Distribution line upper level of typical average 20

*All power line levels above are taken from U.S. National Institute of Environmental Health Sciences (NIEHS) EMF Questions & Answers, pages 36 and 37. As noted by NIEHS, field levels of transmission lines can approximately double during peak loads which occur about 1% of the time.

How much research has been done on EMF and health?

Typical EMF Levels from Power Lines* compared to EMF Exposure Guidelines (in milligauss)
44 years 2,900 studies $490 million spent

* Repacholi M, “Concern that ‘EMF’ magnetic fields from power lines cause cancer.” Sci Total Environ (2012), doi:10.1016/j.scitotenv. 2012.03.030, page 3. [citing PubMed]

How does EMF from power lines compare to “radiation” from sources such as medical X-rays and ultraviolet sunlight?

EMF can be confused with radiation like medical X-rays and ultraviolet sunlight because the term “radiation” is often used to refer to two very different things.

“Radiation” is a scientific term that simply describes how energy travels from a source. A rock tossed into a pond is a source of energy where it lands and causes ripples that “radiate” out in circles - that is “radiation.” TV and radio broadcast towers, power lines, appliances, and home wiring all have fields that radiate out from the source.

The term “radiation,” however, is also used to refer to very different fields, such as those from medical X-rays or the ultraviolet part of sunlight. Exposure to fields from those sources can damage the DNA in cells, which can lead to cancer. A good example is overexposure to sunlight, which can lead to skin cancer. The damage occurs by a process called ionization, so those fields are categorized by science as “ionizing” radiation.

EMF from power lines, electrical appliances, and home wiring, however, is not strong enough to damage DNA, so it is not the same as radiation from medical X-rays or the ultraviolet part of sunlight. EMF, therefore, is categorized as “non-ionizing.” The capability to damage DNA is determined by the “frequency” of the source. Frequency is measured in Hertz. For a source to produce enough energy to damage DNA, it must be at a frequency of approximately ten thousand billion Hertz. EMF from the use of electricity is at a frequency of only 60 Hertz in Canada and the U.S.

Comparison of Field Frequencies
Source of Field Lowest Frequency Field of Source (Hertz)
Ionizing Radiation
 xray
 
Medical X-rays 1,000,000,000,000,000,000
 sun
 
Most ultraviolet sunlight 10,000,000,000,000,000
Non-ionizing Radiation
 eye
 
Visible light 100,000,000,000,000
 radio
 
Radio broadcast at a low frequency 10,000
 lightbulb
 
Electricity 60

What conclusions have government health authorities reached about whether EMF causes health effects?

Here are some examples taken from current websites (see links in the next section):

U.S. National Institute of Environmental Health Sciences:

“Over the past 25 years, research has addressed the question of whether exposure to power-frequency EMF might adversely affect human health. For most health outcomes, there is no evidence that EMF exposures have adverse effects. There is some evidence from epidemiology studies that exposure to power-frequency EMF is associated with an increased risk for childhood leukemia. This association is difficult to interpret in the absence of reproducible laboratory evidence or a scientific explanation that links magnetic fields with childhood leukemia.”

Health Canada:

“[T]he vast majority of scientific research to date does not support a link between ELF [extremely low frequency] magnetic field exposure and human cancers.”

Australian Radiation Protection and Nuclear Safety Agency:

“The scientific evidence does not firmly establish that exposure to 50 Hz electric and magnetic fields found around the home, the office or near power lines is a hazard to human health.”

Where else can I find information about EMF and health? Here are some good places to start: