What Is EMF?

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Electric and magnetic fields (EMFs)—also referred to as "radiation"—are invisible areas of energy that are produced by electricity. Common sources include power lines, cell phones, and microwaves. In the 1990s, there was concern about a potential link between EMFs and childhood cancers, there hasn't been strong research evidence to back that up.

Cellular tower. Equipment for relaying cellular and mobile signal

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What Is EMF?

Many of the most common electronic devices today produce EMFs, meaning that we're surrounded by this type of radiation all day, every day. And while there has been extensive research looking into the potential harms of EMFs, so far there haven't been any conclusive links. But that also doesn't mean scientists know for certain that they are completely safe.

Currently, there is no consensus on whether to treat EMFs as a potential threat to human health. For example, the World Health Organization’s International Agency for Research on Cancer (IARC) has said that EMFs are "possibly carcinogenic to humans," but there hasn't been an equivalent at the American federal level.

Types of EMF

There are two types of EMFs:

  • Non-ionizing EMFs: These are low-level radiation, which, based on current research, are thought to be harmless to humans.
  • Ionizing EMFs: These are high-level radiation, which has the potential to cause cellular and DNA damage. Here's what to know about each type.

Non-Ionizing EMFs

Non-ionizing EMFs consist of low-to-mid-frequency radiation, both natural and manmade. For example, the earth’s magnetic field (i.e. the reason the needle on a compass points North) is one example of a naturally occurring non-ionizing EMF. Non-ionizing EMFs are not especially potent, and as a result, aren't thought to be a threat to human health. Forms of non-ionizing radiation include:

  • Extremely Low Frequency (ELF)
  • Radio Frequency (RF)
  • Microwaves
  • Visual Light
  • Static fields (electric or magnetic fields that do not vary with time)
  • Infrared radiation

Sources of non-ionizing EMFs include:

  • Microwave ovens
  • Computers
  • House energy smart meters
  • Wireless (wifi) networks
  • Cell Phones
  • Bluetooth devices
  • Power lines
  • MRIs
  • Shavers
  • Hairdryers
  • Electric blankets
  • Radios
  • Televisions
  • Millimeter-wave machines (used in airport security screening)
  • Metal detectors (used in airport security screening)

Ionizing EMFs

Ionizing EMFs consist of mid-to-high-frequency radiation which can, under certain circumstances, lead to cellular and or DNA damage with prolonged exposure. Forms of ionizing radiation include:

Sources of ionizing EMFs include:

  • Sunlight
  • X-Rays
  • Some Gamma Rays
  • Backscatter passenger scanners at airports
  • Cabinet X-ray machines used to scan luggage at airports

The Health Risks of EMF

When there is talk of the potential health risks of EMFs, most of the time, it's referring to non-ionic manmade EMFs—like the ones given off by electronic devices like computers, phones, and televisions—rather than the natural radiation given off in the form of ultraviolet (UV) light from the sun. At this stage, the science behind how UV radiation is harmful to human health is well-understood. This includes the knowledge that UV rays can cause sunburns, skin cancer, skin aging, snow blindness (a sunburn to your cornea that causes a temporary loss of vision), and can lower your body’s ability to fight illness.

Research into whether EMFs from power lines could cause cancer goes back at least as far as the 1970s. Specifically, a 1979 study pointed to the possible association between living near power lines and childhood leukemia. But, more recent research, including studies from the 1990s and into the 2010s, had mixed findings. Most found no association between power lines and childhood leukemia and the studies that did found one only for children who lived in homes with very high levels of magnetic fields, which are not common in residences.

Numerous other studies have looked into other forms of technology that emits EMFs—including WiFi and various household electrical appliances—but none found evidence of an association between the use of technology and childhood cancer risks.

Research conducted on adults has found no evidence of increased cancer risk from living near power lines. There is also no conclusive evidence that cell phone use could be harmful to human health, though scientists acknowledge that more research in this area is needed, as well as into the potential health risks of wireless routers.

EMF Safety

Though there is no scientific consensus on the health risks of manmade EMFs, some people may choose to avoid the radiation given off by electronic devices as much as possible out of an abundance of caution. Here are a few examples of how to do that:

  • Limit use of your cell phone and other devices. This means using them less frequently and for shorter amounts of time.
  • Text instead of calling. It uses a much smaller signal than a voice call, resulting in less exposure to EMFs.
  • Use a headset or speakerphone when making calls. The idea is to keep your phone at a greater distance away from your body.
  • Make sure your cell phone reception is as strong as possible. If you have poor reception, some phones will boost their signal to try to make a better connection, which increases the amount of EMF exposure.
  • Request a pat-down at airport security. Those concerned about X-ray or millimeter wave screening, are not required to walk through these machines at the airport and may opt for a pat-down search instead.
  • Take the usual protections during periods of sun exposure. This includes wearing sunscreen and protective clothing, as well as staying out of the sun between 10 a.m. and 4 p.m. and seeking shade whenever possible. Sunlight is a source of EMFs and can cause skin cancer and other damage.
  • Request an EMF reading from your local power company. If you are worried about EMFs emitted by a power line or substation in your area, your local power company can do an on-site reading.

A Word From Verywell

Research into potential health risks from EMFs is still very much ongoing. This includes shorter studies, as well as those that assess the impact of EMFs over much longer periods of time. Like so much of our newer technology, scientists don't yet know the longer-term effects non-ionizing EMFs might have on the human body.

For now, the best we can do is work with the information we have, and for the most part, that indicates that non-ionizing EMFs don't cause cancer in children or adults. And if taking extra precautions with devices that emit EMFs makes you feel as though you're more in control over your health, strategies like reducing cell phone usage or requesting an EMF reading in your local area won't cause you any harm.

8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. National Cancer Institute. Electromagnetic fields and cancer.

  2. International Agency for Research on Cancer. Agents classified by the IARC monographs, volumes 1–128.

  3. National Institute of Environmental Health Sciences. Electric & magnetic fields.

  4. Environmental Protection Agency. Radiation and airport security scanning.

  5. Environmental Protection Agency. Ultraviolet (UV) radiation and sun exposure.

  6. Kaune WT. Assessing human exposure to power-frequency electric and magnetic fields. Environmental health perspectives. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1519693/. Published December 1979. doi:10.1289%2Fehp.93101s4121

  7. Kheifets L, Ahlbom A, Crespi CM, et al. Pooled analysis of recent studies on magnetic fields and childhood leukemiaBr J Cancer. 2010;103(7):1128-1135. doi:10.1038/sj.bjc.6605838

  8. Environmental Protection Agency. Non-ionizing radiation from wireless technology.

By Elizabeth Yuko, PhD
Elizabeth Yuko, PhD, is a bioethicist and journalist, as well as an adjunct professor of ethics at Dublin City University. She has written for publications including The New York Times, The Washington Post, The Atlantic, Rolling Stone, and more.