With the rise in the use of telecommunication devices such as cell phones and WiFi comes a growing concern for health risks which may be associated with radiation exposure. Most parents in our generation did not grow up with cell phones or WiFi, so education about these technologies was not readily available. Many do not understand what radio waves are, how they work, or how we are exposed to them in our environment. This has caused some very understandable concern over how newer technologies may be affecting us and our children.
Misunderstandings surrounding radiation have led to a very large, predatory market of scam products designed to make money from fear and a general lack of education on the subject. With frightening and false claims regarding radiation and elec- tromagnetic fields posted on blogs and sales websites for products that claim they can protect the buyer from radiation, it can be very difficult for readers to determine what is true.
As children, we heard the word “radiation” when discussing things like atom bombs and nuclear power plants. Because of limits in education, times of threatened nuclear war, and comical children’s television programming, most grew up to associate the word “radiation” with danger.
Most types of radiation, however, are completely harmless. By definition, “radiation” is the process by which energy is emitted as particles or waves. Sound, visible light, and heat are also all types of radiation. A few types such as x-ray, gamma ray, and ultraviolet radiation are harmful.
Cell phones and WiFi send signals via an extremely weak form of light known as radio. Radio waves are at the weakest end of what is known as the electromagnetic spectrum. This is a range of light listed from strongest to weakest based on the wavelength of light. This wavelength is also called the electromagnetic frequency. (5)
All forms of light on the electromagnetic spectrum are made of photons (or quanta). A photon is basically a tiny packet (quantum) of light energy. All photons move at the speed of light. All electromagnetic radiation is made of the same photons. The difference comes in how much energy the photon carries. The amount of energy carried by a photon can be measured in its wavelength. (4)
Photons behave both as a particle and as an energy wave. When there is more energy behind the photon it increases the vibration of the photon. The more energy it carries, the faster it vibrates. How much energy the wave carries and how fast it vibrates determines how powerful, damaging, or harmful it is. So how do we know if a light wave is safe or dangerous? Essentially, it depends on how fast it is vibrating. (3)(6)
Everything emits electromagnetic (photon) radiation. There is nothing that does not, it is not limited to WiFi or cell phones. The electromagnetic spectrum is grouped into types of light based on its power or wave-length. From weakest to strongest, they are listed as radio waves, microwaves, infrared, visible light, ultraviolet, x-rays, and gamma rays. (6)(11)
The strongest end of the spectrum is comprised of what we call ionizing radiation. Ionizing radiation is extremely high frequency meaning it vibrates extremely quickly and has a very small wavelength. Ionizing radiation contains enough energy to cause damage at the atomic level. It is powerful enough to damage molecules and DNA and cause cancer. (3)(7)
The wavelengths of ionizing light include gamma rays, x-rays, and ultra-violet rays. Just lower on the scale is visible light which is the range of light that humans can see. Visible light and anything weaker than itself are not powerful enough to damage molecules or DNA. Their wavelength is too long and not small enough to affect anything at the nuclear level. The photons do not carry enough energy. We call this type of weaker radiation non-ionizing.
Visible light, the most powerful type of non-ionizing radiation, is followed by the next most powerful: infrared. The human body generates very large amounts of infrared radiation. For creatures that can see infrared light such as mosquitoes, we glow. Humans cannot see infrared light, but it is powerful enough that we can easily feel it as heat. Ovens and stovetops cook food using infrared radiation.
Just below infrared is microwave radiation. Microwaves are generally harmless, but extremely large amounts can be focused in one area to heat food such as in microwave ovens. Microwaves are very low frequency and only radio waves are weaker than microwaves. Radio waves have the lowest power of all types of light.
A simplified way to imagine how photons affect humans, is to imagine one as a marble. All light is made up of photons which are, essentially, identical. Imagine that the photon is a glass marble. It is harmless and non-toxic, but its danger does not come from what it is. The danger comes from how much force is behind that marble –the amount of energy that it carries with it.
Image Source: NASA
The marble by itself is harmless, but if you were to put it into a gun and shoot it at someone like a bullet, it would harm or possibly kill them. This would be similar to ionizing forms of radiation. They are very high-powered because of the force with which they are emitted from their source.
If you were to toss the marble to someone, that would be more like visible or infrared light. They would feel it but it will not damage the person. This is non-ionizing light. The very weakest form of light, radio waves, would be like very gently rolling the marble across the floor toward someone so that they do not even feel it when it taps them.
Wireless devices use radio frequency. Short, fast flashes of radio are released which are then picked up by receiving devices and the pattern of the signal is then interpreted by the receiving device. Many radio waves are able to travel long distances because they are not blocked by Earth’s atmosphere.(5)
We are continuously enveloped in radio waves every moment of our lives. A tiny amount is produced by electronic devices but the majority of radio waves we are exposed to come from the Earth itself and from space, especially our sun. (1)(8)
A few human sources of radio waves include computers, printers, WiFi, cell phones, televisions, remote controllers, garage door openers, baby monitors, wireless electronics, cordless phones, appliances, RC cars and drones, radio stations, television stations, security surveillance systems, invisible pet fences, telecommunications towers, satellites, aircraft, watercraft, GPS devices, two-way radios such as walkie-talkies, and broadcast antennae.
But human sources of radio waves are small in comparison to the massive amounts of radio waves we are exposed to naturally. Lightning is a large, natural source of radio waves which travel around the earth constantly. (1) The Earth, itself, produces radio waves which is typical of many large objects in space. All stars produce large amounts of radio waves, including our sun. These powerful radio waves are even strong enough to disrupt communication systems on Earth. (1)(8)(9)
We are also exposed to radio waves from the many billions of stars and other bodies in space. Earth’s atmosphere does not block most radio waves, so astronomers are able to see faraway stars and galaxies using radio telescopes.(10)
Most radio waves do not affect human tissue. The wavelength of most radio waves is so long that it passes around us or straight through us in a sort of ghost effect, as though we were not there at all, much the same way that visible light from a lightbulb passes through glass without affecting the glass. So, in general, humans do not absorb most radio frequency. An immeasurable amount of radio waves may be absorbed by the body in the form of heat. (3)
When an electromagnetic wave passes through something, nothing happens. It retains its path and its energy and continues on. But when it hits something that it cannot pass through such as a light hitting a wall, the radiation is stopped and absorbed. When the radiation is absorbed, its energy is transferred and becomes heat. (3)(6)
Lower frequency energy sources carry much less energy and under normal circumstances, they are not capable of warming human tissues. You typically need a much higher frequency. Humans produce very large amounts of higher frequency infrared radiation. This is why we are so warm. (11)(12)
Large amounts of radio waves can cause a small amount of heating such as if you were to stand against a very large radio transmitter. However, the amount of radio waves a human is typically exposed to cannot cause any heating. All human sources of radio waves are strictly controlled by the FCC to ensure that no one is exposed to enough radio waves to cause tissue heating ef- fects. (2) Some people, when made aware of wireless devices, claim that they can feel the effects of low-level radiation. However, in controlled studies, the same people are not able to tell whether or not they have been exposed. (14)(15)
Studies continue on how different types of radiation may affect human health. Despite mountains of research, no scientific studies have ever shown any danger or correlation between everyday levels of radio frequency and human health. Just to be on the safe side, however, the FCC very closely monitors and regulates the use of telecommunication and consumer devices which produce and use radio and microwave frequency until further research can rule out all possibility of cancer. (13)(18)
Even if radio frequency were found to be harmful, it is nearly impossible to prevent exposure. Living in a rural area without cell service and avoiding owning electronics or cell phones would still only reduce one’s exposure by a minuscule amount. And while this does not mean that science will never find a way in which radio waves are harmful, for now, no evidence shows that exposure from radio frequency at current normal levels affects humans.
References and Further Reading:
- Earth Songs, NASA Science Beta. NASA 2016. https://science.nasa.gov/sci- ence-news/science-at-nasa/2001/ast19jan_1/
- RF Safety Solutions: FCC Regulation. http://rfsafetysolutions.com/RF%20Radia- tion%20Pages/FCC_Regulations.html
- The Interaction of Radiation with Matter; Copyright 2016, Department of Physics and Astronomy, Georgia State University. http://hyperphysics.phy-astr.gsu.edu/hbase/mod3.html
- What is a Photon? Definition and Properties. About Education. August 2, 2016. http://physics.about.com/od/lightoptics/f/photon.htm
- Radio Waves to Gamma Rays. Astro 801: Planets, Stars, Galaxies, and the Universe. Penn State University, 2016. https://www.e-education.psu.edu/astro801/content/html
- Types of Radio Waves, Introduction: Light Waves and the Electromagnetic Spec- trum. National Radio Astronomy Observatory, 2016. https://public.nrao.edu/types-of- radio-waves
- Ionizing Radiation and Humans – The Basics. By H. M. Doss, Physics Central, The American Physics Society, 2016. http://www.physicscentral.com/explore/action/ra-cfm
- Radio Waves. NASA, Mission: Science, 2016. http://missionscience.nasa.gov/ ems/05_radiowaves.html
- Solar Flares and Disturbances for Radio Propagation. Electronics Notes, 2016. https://www.electronics-nocom/articles/antennas-propagation/ionospheric/so- lar-flares.php
- Observatories Across the Electromagnetic NASA: Imagine the Universe!, NASA 2016. http://imagine.gsfc.nasa.gov/science/toolbox/emspectrum_observato- ries1.html
- Radiation Emitted by the Human Body by Olivia LEE Shuk-ming, Hong Kong Obser- vatory Educational Resources, 2010. http://www.hko.gov.hk/education/edu02rga/radiation/radiation_02-e.htm
- Infrared Waves: Infrared Energy. NASA, Mission: Science, 2016. http://mission-nasa.gov/ems/07_infraredwaves.html
- Electromagnetic Fields and Public Health: Mobile Phones – Fact sheet N°193. World Health Organization. Reviewed October 2014. http://www.who.int/mediacentre/ factsheets/fs193/en/
- Electromagnetic hypersensitivity: a systematic review of provocation studies. by Rubin GJ, Das Munshi J, Wessely S, 2005. Psychosom Med. 67 (2): 224–232. https:// ncbi.nlm.nih.gov/pubmed/15784787
- Radiofrequency electromagnetic field exposure and non-specific symptoms of ill health: a systematic review. by Röösli M, 2008. Environ. Res. 107 (2): 277–287. https:// ncbi.nlm.nih.gov/pubmed/18359015
- Introduction to the Electromagnetic Spectrum. NASA, Mission: Science, NASA 2016. http://missionscience.nasa.gov/ems/01_intro.html
- What Is the Electromagnetic Spectrum? NASA, NASA 2016. http://hub- blesite.org/reference_desk/faq/answer.php.id=70&cat=light
- Microwaves, Radio Waves, and Other Types of Radiofrequency Radiation: What is Radiofrequency (RF) Radiation? The American Cancer Society. Last revised 05/31/2016.http://www.cancer.org/cancer/cancercauses/radiationexposureand-cancer/radiofrequency-radiation