Those using mobile phones are 96% of American adults. With such widespread use and the need for faster speeds and more data, the latest generation of mobile phone technology, 5G, seems to be on everyone’s radar.
Environmental Factor spoke with Dr. Michael Wide, a toxicologist at the National Toxicology Program (NTP), to learn more about 5G and mobile phone radio frequency emissions (RFR) research at NTP.
Wide works in the Toxicology Division of the NTP Division. (Photo provided by Steve McCaw)EF: What exactly is 5G technology?
MW: 5G is the fifth generation of mobile phone technology that promises higher data transfer speeds, lower network latency, and increased network capacity compared to previous generations.
2G and 3G cellular networks, primarily used for voice calls and text messages, operate on specific frequencies between 800 and 1,900 megahertz (MHz). 4G and 4G-LTE networks, which include additional frequencies from 700 to 2,500 MHz, were developed to support growing data needs such as streaming video, Internet access, and file downloads.
Today’s mobile phones use multiple antennas and work across 2G, 3G, and 4G platforms to provide maximum geographic coverage, connectivity, and speed. 5G technology uses the same frequencies as older technology, but also features higher RFR frequencies known as millimeter waves.
Reaching up to 60,000 MHz, these higher frequencies can quickly transmit vast amounts of data with increased network capacity. Therefore, it is expected that wireless users will be exposed to a wider range of her RFR frequencies as we move forward.
EF: Will 5G increase radiation levels in mobile phones?
MW: It’s difficult to compare 5G to previous generations of wireless networks, given some of the issues I mentioned earlier. NTP scientists continue to work to understand the effects of RFR exposure on living tissues, regardless of generation.
Millimeter waves, such as those used in 5G, are known to not travel as far or penetrate as deeply into the body as the low-frequency RFR used in current 2G, 3G, and 4G networks. Much of the absorption at high frequencies occurs in the skin.
At lower frequencies, RFR has been shown to penetrate at least 3 to 4 inches of the human body. In our studies in rats, exposure to 900 MHz RFR induced tumors in the heart, brain, and adrenal glands. However, 5G mmWave frequency RFR does not penetrate deep enough to reach these tissues.
Additionally, the higher frequencies of 5G networks reach shorter distances and do not pass through physical barriers, requiring significantly more transmitters and antennas to provide coverage to consumers. Therefore, humans may be closer to the antenna, potentially increasing radiation exposure.
5G networks may require more transmitters and antennas, which may increase the exposure of mobile phones to RFR.However, due to the increased number of antennas, 5G RFR power levels are likely to be lower than those currently used in 2G, 3G, and 4G. At this time, it is unclear exactly how exposure to her RFR varies in humans. What we do know is that while wireless consumers will continue to be exposed to current frequencies, they will also be exposed to higher frequencies.
EF: How does NTP plan to study the health effects of 5G?
MW: NTP is evaluating the existing literature on radiofrequency for use in 5G networks and is working to better understand the biological basis of cancer findings reported in 5G networks. Previous research on RFR using 2G and 3G technologies.
Additionally, work is underway to develop smaller RFR exposure chambers for short-term rodent studies that would take weeks or months rather than years to complete. New exposure systems can also evaluate new technologies in the telecommunications industry.
NTP also aims to repeat DNA damage studies in smaller RFR exposure chambers and identify biomarkers of damage from RFR exposure. Biomarkers are measurable physical changes, such as molecular changes, that can be observed over a shorter period of time than it takes for cancer to develop and may be predictive of disease.
The more scientists can understand the biological changes in animals, the better they will know what to look for in humans.
(Dr. Sheena Scruggs is the Digital Outreach Coordinator in the NIEHS Office of Communications and Public Liaison.)
