According to the WHO, the "precautionary principle" is "a risk management policy applied in circumstances with a high degree of scientific uncertainty, reflecting the need to take action for a potentially serious risk without awaiting the results of scientific research." Other less stringent recommended approaches are prudent avoidance principle and as low as reasonably practicable. Although all of these are problematic in application, due to the widespread use and economic importance of wireless telecommunication systems in modern civilization, there is an increased popularity of such measures in the general public, though also evidence that such approaches may increase concern.[35] They involve recommendations such as the minimization of cellphone usage, the limitation of use by at-risk population (such as children), the adoption of cellphones and microcells with as low as reasonably practicable levels of radiation, the wider use of hands-free and earphone technologies such as Bluetooth headsets, the adoption of maximal standards of exposure, RF field intensity and distance of base stations antennas from human habitations, and so forth.[citation needed] Overall, public information remains a challenge as various health consequences are evoked in the literature and by the media, putting populations under chronic exposure to potentially worrying information.[36]
The papers found that, in male rats, there was “clear evidence” that exposure to cell phone radiation increased risk for a rare type of malignant tumor called schwannoma in the connective tissues that surround nerves in the heart (they found “equivocal” evidence for the same thing in female rats). They also found “some evidence” that the radiation caused malignant glioma—a type of brain cancer affecting glial cells—in the male rats.
That brings us back to the main question here: Do cellphones cause tumors? We chose to focus this story on cancer risk, since it seems like the most common health concern people have about cellphones. But before we get to the answers, we need to take another (brief) detour to explain how this science has been done with human subjects. To do that, we need to zoom in on a nerdy subject: research methods.
“Epidemiological studies are targets for fixing the outcome because they’re observational in nature instead of experimental,” Dr. Carlo explains. “It’s possible to design studies with pre-determined outcomesthat still fall within the range of acceptable science. Thus, even highly flawed epidemiological studies can be published in peer-reviewed journals because they’re judged against a pragmatic set of standards that assume the highest integrity among the investigators.”
These cases work by redirecting the electromagnetic radiation (EMR) that is produced by phones, away from the user. All phones produce EMR when connected to the mobile network, and the effect of this energy is measured as a Specific Absorption Rate, or SAR: a measurement describing the radiation absorbed by kilogram of tissue. Government regulations in Australia dictate that all phones in Australia must emit a SAR less than 2 W/kg under the worst case scenario, and while all phones comply, most modern phones emit, at most, only half of this safe level, or approximately 1 W/kg.
Third, most of the studies published so far have focused on adults, rather than children. (One case-control study looking at children and teens did not find a significant link to brain tumors, but the small size of the study limited its power to detect modest risks.) Cell phone use is now widespread even among younger children. It is possible that if there are health effects, they might be more pronounced in children because their bodies might be more sensitive to RF energy. Another concern is that children’s lifetime exposure to the energy from cell phones will be greater than adults’, who started using them at a later age.

Remember: The cancer incidence data in humans, at least to date, suggests no avalanche of head and neck tumors. Since so many people are exposed to cellphones, if there were a big risk, we’d probably see it turn up. “If cellphones caused brain tumors at the rate that cigarettes caused lung cancer,” said Otis Brawley of the American Cancer Society, “we would have figured it out by now.”
The following is an excerpt of a typical conclusion published in a scientific journal about the links between EMFs, cell phones and health: "Epidemiologic research shows a low degree of association, inconsistency and missing dose-effect relations. A biologic mechanism of action is still debatable. No harm to human health has been shown. Conclusion: There is no scientific basis as to the harmful effects of EMFs on human health."
The guidelines created a measure of the rate that body tissue absorbs radiation during cell phone use called the specific absorption rate (SAR). The SAR for cell phone radiation was set at a maximum of 1.6 watts of energy absorbed per kilogram of body weight. The limit was set due to the thermal effects of cell phone radiation (all RF radiation can heat human body tissue at high enough levels) - it was not set to mitigate other biological effects cell phone radiation might have such as DNA damage or cancer.
The studies are notable for their sizes. Researchers at the National Toxicology Program, a federal interagency group under the National Institutes of Health, tested 3,000 rats and mice of both sexes for two years—the largest investigation of RF radiation and cancer in rodents ever undertaken in the U.S. European investigators at the Ramazzini Institute in Italy were similarly ambitious; in their recent study they investigated RF effects in nearly 2,500 rats from the fetal stage until death.

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.
But the results of these two rat studies align with those of the biggest cell phone-radiation human study to date, INTERPHONE. The INTERPHONE study, published in 2011, was a coordinated effort by researchers at 16 institutions across 13 countries, and found that the heaviest mobile phone users were more likely to develop glioma—the same type of brain cancer the NTP study found in the male rats. “So there’s a concordance between the animal and human data,” Melnick says.
Thanks for reading the fine print. About the Wiki: We don't accept sponsorships, free goods, samples, promotional products, or other benefits from any of the product brands featured on this page, except in cases where those brands are manufactured by the retailer to which we are linking. For our full ranking methodology, please read about us, linked below. The Wiki is a participant in associate programs from Amazon, Walmart, Ebay, Target, and others, and may earn advertising fees when you use our links to these websites. These fees will not increase your purchase price, which will be the same as any direct visitor to the merchant’s website. If you believe that your product should be included in this review, you may contact us, but we cannot guarantee a response, even if you send us flowers.
Remember: The cancer incidence data in humans, at least to date, suggests no avalanche of head and neck tumors. Since so many people are exposed to cellphones, if there were a big risk, we’d probably see it turn up. “If cellphones caused brain tumors at the rate that cigarettes caused lung cancer,” said Otis Brawley of the American Cancer Society, “we would have figured it out by now.”
As a result, stories about a single nuclear meltdown or possible link between cellphone radiation and cancer will be amplified much more than news about the nine people who probably died today in the US from distracted driving. “This possible health effect from radiation is pretty esoteric at this point. If there is anything there, it seems to me like it’s going to be very, very small,” says Kenneth R. Foster, a bioengineering professor at the University of Pennsylvania who has been investigating whether there are biological effects from radio waves since the 1970s. “Driving and texting, people get killed doing that — but it’s not a very exciting risk to worry about.”
5. Use an EMF shielding device. A variety of holsters and other cell phone holders and shields are available that claim to block radiation. If you buy such a product, look to see if it has an SAR (specific absorption rate) value. You want a shielding device that blocks the majority of EMFs. (SAR is a measure of the rate at which energy is absorbed by a body exposed to EMFs.) 
“It’s quite informative that the NTP data found evidence of an increased tumor risk in the male rats for glial cells and in the [heart] Schwann cells,” said Joel Moskowitz, director of the Center for Family and Community Health at the Berkeley School of Public Health (who writes about electromagnetic radiation here). “That’s compelling evidence that what we’re seeing in humans — even though the signal is not clear — is highly suggestive, and that there is indeed something real going on with regard to tumor risk in humans.”
These expert committees determined that there are indeed gaps in the knowledge concerning the implications of exposure to this radiation, and therefore they called for further studies on the subjects and recommended to adopt the “precautionary principle". This principle adopts simple and relatively cheap means to reduce exposure to the minimum radiation levels possible with existing technology.
It’s true that cellphones do emit radiation. And radiation is a scary word for a lot of people, thanks in part to the horrific aftermath of nuclear accidents and photographs of victims of the nuclear bombs the US dropped on Japan in World War II. People hear radiation and they associate it with nuclear radiation and the bomb, says Geoffrey Kabat, a cancer epidemiologist at the Albert Einstein College of Medicine and author of the book Getting Risk Right. “There are all these associations and those are deeply ingrained in people. But it doesn’t apply here.”

Leibovich was very careful to point out in our interview that Cellsafe is not claiming that the radiation absorbed by the body during phone use leads to health issues like brain tumours, male infertility or damage to unborn babies. But the Cellsafe website strongly suggests these links. Its homepage (image below) leads with the phrase "You should be concerned!" in an eye-catching red, and there is as much screen real estate on the site dedicated to information about the dangers of radiation, as there is for descriptions of the Cellsafe products. This information refers to "high levels of RF radiation" in several places, but it doesn't say whether this describes radiation from phone use.
But there is also some ambiguity about cellphone radiation’s health effects. As Dr. John Bucher, a senior scientist at the National Institute of Environmental Health Sciences and a co-author of the NIH studies, told me, “[Our results] go against the notion that non-ionizing radiation is completely harmless.” In other words, he’s found that the type of radiation cellphones give off could cause biological changes, like promoting tumors, at least in animals.
There’s no question that portable phones and computers offer many conveniences and have made our lives easier in countless ways. For many people this convenience outweighs the worry of EMFs. My hope is that by becoming aware of the sources and dangers of cell phone radiation and EMFs, you’ll take steps to minimize exposure for both you and your family.
As far as which of those match your device, that really depends on your carrier. AT&T, Verizon, Sprint, and T-Mobile all have different frequencies. To further complicate things, in one geographic region of the country they may use one frequency, while another is used elsewhere. It all depends on which FCC licenses they have the rights to in each region.
This 2017 systematic review and meta-analysis, published in PLOS One, looked at mobile phone use in case-control studies and the risk of glioma. “Our results suggest that long-term mobile phone use may be associated with an increased risk of glioma,” they wrote. The researchers found an association between mobile phone use and low-grade glioma in the people who used cellphones regularly or for 10 years or more. “However, current evidence is of poor quality and limited quantity,” they added, and called for prospective studies to confirm the results.

The authors of these studies noted that the results were preliminary and that possible health outcomes from changes in glucose metabolism in humans were unknown. Such inconsistent findings are not uncommon in experimental studies of the biological effects of radiofrequency electromagnetic radiation in people (4). Some factors that can contribute to inconsistencies across such studies include assumptions used to estimate doses, failure to consider temperature effects, and lack of blinding of investigators to exposure status.