Electromagnetic Fields (EMFs)
Electric & Magnetic Fields
Electric and magnetic fields (EMFs) are invisible lines of force associated with the production, transmission, and use of electric power such as those associated with high-voltage transmission lines, secondary power lines, and home wiring and lighting. Electric and magnetic fields also arise from the motors and heating coils found in electronic equipment and appliances.
Because the use of electric power is so widespread, humans are constantly exposed to electric and magnetic fields. Studies conducted in the 1980s showed a link between magnetic field strength and the risk of childhood leukemia. After reviewing more than two decades of research in this area, NIEHS scientists have concluded that the overall pattern of results suggests a weak association between increasing exposure to EMFs and an increased risk of childhood leukemia. The few studies that have been conducted on adult exposures show no evidence of a link between residential EMF exposure and adult cancers, including leukemia, brain cancer, and breast cancer. Based on these reviews, the NIEHS recommends continued education on practical ways of reducing exposures to EMFs.
Winnipeg Regional Health Authority's PDF on EMFs
based on “Questions and Answers About EMF Associated with the use of Electric Power.” November 2001 NIEHS and US Department of Energy (Jan 1995) and World Health Organization Fact Sheets No 205 (Nov 1998) and No 263 (October 2001).
Health and safety
The potential health effects of the very low frequency EMFs surrounding power lines and electrical devices are the subject of on-going research and a significant amount of public debate. In workplace environments, where EMF exposures can be up to 10,000 times greater than the average, the US National Institute for Occupational Safety and Health (NIOSH) has issued some cautionary advisories but stresses that the data is currently too limited to draw good conclusions.
The potential effects of electromagnetic fields on human health vary widely depending on the frequency and intensity of the fields. For more information on the health effects due to specific parts of the electromagnetic spectrum, see the following articles with details of possible dangers (MRI) and some currently unfounded fears (mobile phones):
- Static electric fields: see Electric shock
- Static magnetic fields: see MRI/Safety for one of the few applications in which magnetic fields are strong enough to have safety implications
- Extremely low frequency (ELF): see Power lines/health concerns
- Radio frequency (RF): see Electromagnetic radiation and health
- Light: see Laser safety
- Ultraviolet (UV): see Sunburn
- Gamma rays: see Gamma ray
- Mobile telephony: see Mobile phone radiation and health
What can you do to limit EMF exposure?
- Increase the distance between yourself and the EMF source – sit at arm’s length from your computer terminal; stand back from an appliance when it is in use.
- Correct any household wiring problems
- Avoid unnecessary proximity to high EMF sources – don’t let children play directly under power lines or on top of power transformers for underground lines
- Reduce time spent in the magnetic field – turn off your computer monitor and other electrical appliances when you are not using them.
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