What the health experts are saying
The question of whether exposure to electric and magnetic fields (EMF), in particular magnetic fields, cause adverse health effects has been the subject of numerous scientific studies over the last 40 years.
The extensive health research and scientific knowledge surrounding EMF includes both epidemiological studies and experimental studies in animals, tissues and cells.
Health Canada and the World Health Organization (WHO) position that EMF isn't linked to adverse health effects hasn't changed, despite ongoing research on the topic. Scientific knowledge in this area is now more extensive than for most chemicals. We continue to monitor research and findings by these organizations to ensure we're providing the most up-to-date information.
See the latest research on EMF and read more about their findings around magnetic and electric fields:
In epidemiological studies, researchers try to establish if there’s a statistical association between the exposure of certain groups of people and diseases that they experience. Some epidemiological studies have suggested a weak association between exposure to magnetic fields and childhood leukemia. It’s unclear, however, whether exposure to magnetic fields actually caused the disease.
Some studies don’t include magnetic field measurements when trying to determine an association. No epidemiological study has provided direct evidence that would permit drawing the conclusion that EMF is a cause of cancer or other adverse health effects.
Experimental studies involve exposing cells, tissues and animals to magnetic fields under controlled conditions. These studies allow researchers to closely control magnetic field exposure and provide information about any small scale biological changes that magnetic fields may cause. Experimental studies haven’t provided a basis to conclude that magnetic fields are the cause of any disease.
Many reputable health authorities such as the World Health Organization and Health Canada have conducted thorough reviews of all the different types of studies and research on EMF and health. These health authorities have examined the scientific weight-of-evidence and have determined that when all of the epidemiological and experimental studies are considered together, the consensus is that there is no cause-effect relationship between exposure to magnetic fields and human health.
We continue to monitor the scientific developments related to EMF.
Health Canada has reviewed the current scientific findings regarding exposure to electric and magnetic fields (EMF) and concluded:
There have been many studies on the possible health effects from exposure to EMFs at extremely low frequencies (the category power lines belong to). While it’s known that EMFs can cause weak electric currents to flow through the human body, the intensity of these currents is too low to cause any known health effects. Some studies have suggested a possible link between exposure to power line magnetic fields and certain types of childhood cancer, but at present this association is not established.
As a result:
- Health Canada does not consider that any precautionary measures are needed regarding daily exposures to EMFs at extremely low frequencies.
- There is no conclusive evidence of any harm caused by exposures at levels found in Canadian homes and schools, including those located just outside the boundaries of power line corridors.
The World Health Organization (WHO) has also looked at questions around EMF:
- In 2007, WHO released a comprehensive report on possible health effects of exposure to extremely low frequency electric and magnetic fields. In this report, WHO stated that the evidence related to childhood leukemia is not strong enough to be considered causal.
- WHO has endorsed and adopted the guidelines developed by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). ICNIRP is a Germany-based non-profit scientific organization made up of independent experts that are responsible for providing guidance and advice on non-ionizing radiation protection for people and the environment. In its 2010 guidelines, ICNIRP recommends a residential magnetic field exposure limit of 2,000 milligauss (mG) and an occupational exposure limit of 10,000 mG.
Most of the interest in possible health effects is related to magnetic fields and not electric fields, however, you may notice the presence of electric fields when you’re near power lines.
Conductive objects, like a vehicle, fence line or even the ground can attract an electrical charge when they’re near electric fields. When you touch that object you might experience a startle shock. Startle shocks can feel similar to the small shock that you might feel in your house after shuffling your feet on the carpet and touching a door handle.
Startle shocks aren’t harmful, but understanding how and when they happen can help to reduce surprise if you experience one.
In June 2007, the World Health Organization concluded that there are no substantive health concerns related to electric fields at levels generally encountered by the public (WHO, Fact Sheet No. 322 Electromagnetic fields and public health, June 2007).