The Science of 5G Technology and Your Health
My first cell phone, back in the early 2000’s, was a Nokia 1100. The extent of its capabilities were basic calling, basic text messaging, and surviving high velocity impacts into hard surfaces. Despite 3G networks being commercially available two years before the Nokia 1100’s release in 2003, the phone operated solely within the 2G network. But what do these 2G, 3G, 5G networks mean, anyway? Do we just add a new digit every couple of years when the networks get better? Why are people worried about the dawn of 5G in ways that we weren’t for 3G or 4G?
What is 5G?
The cell phone service provider Verizon defines 5G as, “the fifth generation of wireless technology” [1]. Each generation of wireless technology has been marked by specific improvements in capabilities.
The first generation, 1G, was introduced in 1979 and offered the ability to make phone calls from a wireless device on an analog network.
The second generation of wireless technology, 2G, became commercially available in 1991 and transitioned us into the digital age while introducing text messaging and voicemail systems.
3G launched in 2001, adding data features to mobile phones such as sending picture messages, streaming music, web browsing, and social media. This effectively was the dawn of smartphones.
4G networks rolled out around 2009 which increased data speeds substantially, allowing for faster internet browsing, video calls, and online mobile gaming.
Cellular networks have already begun testing 5G networks in major cities. The immediate advantage of 5G is data speed up to five times faster than 4G, and over time the speed could increase to twenty times faster than 4G. Along with increased data speed, 5G offers increased device connectivity for smart machines, such as Google smart speakers, and lower latency [2,3]. Note, 5G cellular is also not to be confused with 5 Gigahertz (GHz) Wi-Fi which is a local wireless network operating with specifically a 5GHz frequency.
How does it Work?
The technology behind 5G is called “5G New Radio” or “5G NR”. A combination of advanced processors in mobile devices and improved radio tower technology which enables the increased data and connectivity of 5G networks. This means that older phones will not be capable of accessing the entirety of the 5G network, which will be composed of upgraded 4G technology operating under 6GHz frequency as well as new technology operating above 6GHz [4].
Operating on different frequencies offers a variety of benefits. The lower the frequency, the greater the range and building penetration, while higher frequencies offer greater data speeds and lower latency. The frequency range from 30GHz to 300GHz falls into what’s called the millimeter wave spectrum and is the most controversial spectrum in 5G. We can derive why this is within the millimeter wave band using a simple relationship between wavelength and frequency:
Wavelength = Speed of light ÷ Frequency
The speed of light is 300,000,000 meters per second. Gigahertz refers to units of a billion, so 30GHz is equivalent to 30,000,000,000 hertz. Plugging the speed of light and 30GHz into the above equation results in 0.01 meters or 10 millimeters and 300GHz gives 1 millimeter. The reason this frequency range is controversial is that as frequency increases the penetration of the light through objects decreases. In other words, the chance of the photon interacting with matter increases at larger frequencies, which raises concerns about potential damage to the body from radiation. In addition, as the frequency of the light increases, so too does the energy of the light by following the formula:
Energy = Planck's Constant x Frequency
The higher the energy, intuitively, the more damage a photon can do when it interacts with our bodies. You may be wondering why it is that visible light, sandwiched between Ultraviolet light and Microwaves, has no harmful effect on us. The simple answer is that because the sun primarily produces visible light and infrared light, our bodies evolved natural protections from their harmful effects. While other types of radiation are naturally occurring, they occur so infrequently that we did not need to evolve protection against them.
Risks
When thinking about radiation, most people would probably immediately think of harmful forms of radiation such as X-rays, Gamma Rays, and possibly Ultraviolet radiation. In reality, radiation comes in many forms and for the most part is harmless. Visible light is a form of radiation; as radiation simply means the emission of energy as an electromagnetic wave or particle. The dangers of radiation fall into two categories: ionizing radiation and non-ionizing radiation. Ionizing radiation includes Gamma, X-rays, and some of the Ultraviolet spectrum. These frequencies of light have enough energy to strip electrons from atoms. This process releases energy, which damages the surrounding tissue and can lead to carcinogenic mutations.
Non-ionizing radiation does not have enough energy to remove electrons from atoms. It does, however, produce thermal effects [5]. For example, a microwave oven heats food but does not change the physical properties of the food. A piece of chicken cooked in a microwave will still be a piece of chicken after cooking. Further, even visible light can cause thermal effects such as a blue laser being used to pop balloons. For the case of cell phones, it is important to note that they emit non-ionizing radiation.
In 2015 a number of scientists wrote a letter to the United Nations and World Health Organization expressing concerns over the non-ionizing radiation emitted from cellular devices. In their letter they wrote:
“Numerous recent scientific publications have shown that Electromagnetic Fields affect living organisms at levels well below most international and national guidelines. Effects include increased cancer risk, cellular stress, increase in harmful free radicals, genetic damages, structural and functional changes of the reproductive system, learning and memory deficits, neurological disorders, and negative impacts on general well-being in humans. Damage goes well beyond the human race, as there is growing evidence of harmful effects to both plant and animal life.”
Note, the specific scientific publications being referenced are not specified in the letter [6]. In response, the Scientific Committee on Emerging and Newly Identified Health Risks released an extensive opinion regarding the health risks of various types of non-ionizing radiation exposure. The opinion, unlike a published peer-reviewed paper, is a collection of perspectives from various scientists within the European Commision. It does not reflect a scientific consensus, but acts as a counterbalance to scientists with opposing views. The purpose not being to say that those with opposing views are incorrect, but merely to give additional input on the topic. In the opinion it is stated,
“It is clear from the INTERPHONE study (Cardis et al., 2011) that cumulative specific absorption for the early analogue systems were manifold higher than for the next generations of handsets.”
What is being stated is that the total amount of radiation that the body is exposed to from cellular devices has decreased as the technology has improved. When it comes specifically to 5G technology the opinion does say that observation for adverse effects will be important as these technologies are implemented but also states,
“These applications will operate with low power and, due to the small penetration depth of the radiation, expose only superficial tissues” [7].
In other words, at this time, there is no reason to panic over 5G technology increasing harmful radiation exposure. This makes sense when we think back on why using various frequencies is beneficial. Remember, at higher frequencies data can be transmitted faster, but range and penetration through objects is reduced. Since millimeter waves are high frequency, one would expect the depth that they could penetrate the human body to be reduced, which means that the damage that could occur should be mostly superficial. That is, tissues towards the surface, primarily the skin, would be more vulnerable than internal organs.
While the opinion does not reflect a scientific consensus, it does provide many citations for the claims being made giving it more credibility.
Conclusion
To reiterate; at present there is no reason to be overly concerned about the health risks of 5G technology. That said, there are steps you can take to help minimize your exposure to cellular radiation. These include using hands-free headsets, which operate with lower power than a phone, and utilizing speaker phone so that you do not have your cell phone against your head. It is important to consider that the data we currently have does not show a definitive connection between cellular radiation and health risks. Everything else being equal and given how invaluable cell phones are to our modern way of life, it appears as though avoidance at this point would be doing society a disservice. That being said, the scientific community should continue to investigate cell phone technologies and remain vigilant for any injurious health effects moving forward.
References
[2] Mike Freeman. The Race for 5G and What You Need to Know. The Seattle Times. 09/02/2019
[3] Sascha Segan. What is 5G? PCMag. 01/02/2020
[4] Lindsay Notwell. 5g- A Few Frequency Facts. CIO.
[5] CDC. Radiation Studies. 12/07/2015