Generally speaking, the near-field refers to the RF field close to the antenna and the far-field is the RF field further away from the antenna. Often times when you use your cell phone, your body is often located in the near-field (one wavelength or less) of the cell phone antenna. It is especially concerning when you hold your phone next to your head or wear it on your body as you can be exposed to very intense near-field radiation from the phone.
While the Federal Communication Commission limits how much radiofrequency radiation can come out of your cellphone, the Food and Drug Administration can have a say about whether those limits are safe. So the FDA asked the National Toxicology Program (NTP), a division within the National Institutes of Health, to investigate. Based on the NTP’s results, as well as hundreds of other studies, the FDA is still confident that the current limits on cellphone radiation are safe, according to a statement from Jeffrey Shuren, the director of the FDA’s Center for Devices and Radiological Health.
Most cellphone shielding products are designed to reduce radiation to the user while still allowing the phone to function. This means that some radiation can still get to the phone… and some radiation can still get out of the phone! But sometimes you need to completely kill the signal. The RF Kill Box is a full-metal shielding jacket with very high shielding performance.

“The evidence so far doesn’t prove that cell phones cause cancer, and we definitely need more and better research,” says Michael Hansen, Ph.D., a senior scientist at Consumer Reports. “But we feel that the research does raise enough questions that taking some common-sense precautions when using your cell phone can make sense.” Specifically, CR recommends these steps:

The ultra thin (1mm) RadiCushion by Cellsafe slips into the cell phone case and redirects radiation away from the face of the phone. It's available in black or white but not recommended for use with aluminum or metallic cell phone cases. Test results show a SAR reduction of 96%. A slightly thicker (2mm) RadiCushion is available for iPad and iPad mini; it adheres to the back of the device and also provides SAR reductions of 96%. Visit their website for more information or watch this independent test which shows an 80% reduction and also compares it to the BlocSock:
"For example," Johnson said, "what does a fractal like pattern have to do with a hologram? The answer is, of course, nothing that is apparent. Then there is a truly convoluted assertion that cell phones can be instrumental in ‘psychoemotional' effects on humans because of their lower-frequency outputs. This too, is gibberish. In short, this is technobabble that will potentially snow someone who has no science background."
George Carlo, PhD, JD, is an epidemiologist and medical scientist who, from 1993 to 1999, headed the first telecommunications industry-backed studies into the dangers of cell phone use. That program remains the largest in the history of the issue. But he ran afoul of the very industry that hired him when his work revealed preventable health hazards associated with cell phone use.
Just why Schwann and glial cells appear to be targets of cell phone radiation is not clear. David Carpenter, a physician who directs the Institute for Health and the Environment at the University at Albany, S.U.N.Y., explained the purpose of these cells is to insulate nerve fibers throughout the body. These are electrical systems, so that may be some sort of factor, he wrote in an e-mail. “But this is only speculation.”

Cables can act as an antenna, especially if they pass close to a strong source of radiofrequency radiation. One study has suggested that if the cable of a hands free mic passes near the phone's antenna, it can pick up some radiation and transmit it to your ear. Our ferrite snap bead is designed to reduce RF radiation in the cable. Made in 2 halves, you simply press it around the hands free wire at any convenient location near the earpiece end. Couldn't be simpler. It is small and lightweight enough to be almost unnoticable, yet powerful enough (50 ohm impedence minimum) to control nasty radiation. These are brand new, top quality and will accommodate wires up to 5 mm (3/16 inch) in diameter. About 1 inch long, grey color. If you are concerned about radiation from your hands free ear mic, this is the answer. Useful from 200-1000 MHz.

“The evidence so far doesn’t prove that cell phones cause cancer, and we definitely need more and better research,” says Michael Hansen, Ph.D., a senior scientist at Consumer Reports. “But we feel that the research does raise enough questions that taking some common-sense precautions when using your cell phone can make sense.” Specifically, CR recommends these steps:
Some scientists have reported that the RF waves from cell phones produce effects in human cells (in lab dishes) that might possibly help tumors grow. However, several studies in rats and mice have looked at whether RF energy might promote the development of tumors caused by other known carcinogens (cancer-causing agents). These studies did not find evidence of tumor promotion.
That mystery probably stokes fears about cellphone radiation instead of soothing them, though — in part because of how we in the media cover the rare and frightening. We’ve seen the same thing with fear over nuclear power plants, according to a paper published in Science in the 1980s by psychologist Paul Slovic. “Because nuclear risks are perceived as unknown and potentially catastrophic, even small accidents will be highly publicized and may produce large ripple effects,” Slovic wrote.
California officials issued the new report in response to increasing smartphone use in the United States, especially among children. About 95% of Americans own a cell phone, according to a press release from the California Department of Public Health, and the average age for a first cell phone is now 10 years old. About 12% of people use their smartphones for daily Internet access.
Yes, cell phones emit Electromagnetic Fields (EMF) and direct exposure to these emissions can be a health risk. There are two types of EMF radiation emitted from cell phones: Extremely Low Frequency (ELF) radiation and Radio Frequency (RF) radiation (which includes cellular signals, WiFi and Bluetooth). More and more, particularly in recent years, scientific studies have confirmed that these EMF exposure can adversely modify the biological operations of the body. In more serious cases, exposure to EMFs can lead to tumors, reduce sperm count and other serious health concerns.
First, you must have a proper meter. To check for magnetic field emissions, an AC Gaussmeter will work. Most AC gaussmeters will have an internal probe. Simply position the gaussmeter on the phone. Note carefully where the meter is positioned. Make a call and watch the readings. Notice the highest and lowest readings, and make a mental note of the "average" reading. Now, insert the magnetic shield, and repeat.
Taken together, the findings “confirm that RF radiation exposure has biological effects” in rats, some of them “relevant to carcinogenesis,” says Jon Samet, a professor of preventive medicine and dean of the Colorado School of Public Health, who did not participate in either study. Samet, however, cautioned the jury is still out as to whether wireless technology is similarly risky to people. Indeed, heart schwannomas are exceedingly rare in humans; only a handful of cases have ever been documented in the medical literature.

Dr Davis holds a B.S. in physiological psychology and an M.A. in sociology from the University of Pittsburgh, 1967. She completed a PhD in science studies at the University of Chicago as a Danforth Foundation Graduate Fellow, 1972 and a M.P.H. in epidemiology at the Johns Hopkins University as a Senior National Cancer Institute Post-­Doctoral Fellow, 1982. She has authored more than 200 publications and has been published in Lancet and Journal of the American Medical Association as well as the Scientific American and the New York Times.
The effect of mobile phone radiation on human health is a subject of interest and study worldwide, as a result of the enormous increase in mobile phone usage throughout the world. As of 2015, there were 7.4 billion subscriptions worldwide, though the actual number of users is lower as many users own more than one mobile phone.[1] Mobile phones use electromagnetic radiation in the microwave range (450–3800 MHz and 24-80GHz in 5G mobile). Other digital wireless systems, such as data communication networks, produce similar radiation.
Though some findings were reassuring, others do raise concerns. Specifically, three of the studies—one from Sweden, another from France, and a third that combined data from 13 countries—suggest a connection between heavy cell-phone use and gliomas, tumors that are usually cancerous and often deadly. One of those studies also hinted at a link between cell phones and acoustic neuromas (noncancerous tumors), and two studies hinted at meningiomas, a relatively common but usually not deadly brain tumor.
We also spoke to experts and searched government reports to try to find any other high-quality evidence that may not have been published in an academic database. We included the National Toxicology Program’s animal studies, since they are considered some of the most important animal research that was funded by the government to help answer the question of whether cellphones cause cancer. We also included research on the fertility effects of cellphone radiation, since that was a concern many researchers in the field had.

The Specific Absorption Rate that the FCC, with input from many other government institutions, decided on, is defined using an average of a 30-minute phone call with the cell phone held directly to the ear. Since modern cell phones are used in all sorts of manners, ie speakerphone, scrolling through social media, browsing the web, etc, a base had to be set.
Researchers have carried out several types of epidemiologic studies in humans to investigate the possibility of a relationship between cell phone use and the risk of malignant (cancerous) brain tumors, such as gliomas, as well as benign (noncancerous) tumors, such as acoustic neuroma (tumors in the cells of the nerve responsible for hearing that are also known as vestibular schwannomas), meningiomas (usually benign tumors in the membranes that cover and protect the brain and spinal cord), and parotid gland tumors (tumors in the salivary glands) (3).