An important part of the Food and Drug Administration’s (FDA) mission is to ensure the safety of electronic products that emit radiation, like televisions, microwave ovens, and cell phones.
These types of products are part of Americans’ daily life and we take our duty to protect consumers with the utmost gravity.
With cell phones, we have relied extensively on a myriad of scientific evidence developed over many years to help inform our regulatory thinking.
Although the Federal Communications Commission (FCC) sets the standard for radiofrequency energy exposure limits from cell phones, the FCC relies on the FDA and other health agencies for scientific expertise and input regarding those standards.
We respect the recently released research conducted by our colleagues at the National Toxicology Program (NTP), which is part of the National Institute of Environmental Health Sciences (NIEHS), within the National Institutes of Health (NIH), on radiofrequency energy exposure.
When we nominated this topic for study in 1999, there were limited epidemiological and long-term animal studies investigating the effects of radiofrequency energy exposure from cellular phones.
Fortunately, since then, there have been hundreds of studies from which to draw a wealth of information about these technologies which have come to play an important role in our everyday lives.
Taken together, all of this research provides a more complete picture regarding radiofrequency energy exposure that has informed the FDA’s assessment of this important public health issue, and given us the confidence that the current safety limits for cell phone radiation remain acceptable for protecting the public health.
(Learn More. Cell phones aren’t medical devices, but because they give off low levels of radio frequency or RF energy, they’re regulated by the FDA. While research by FDA and other organizations has not linked cell phones with any health hazards, FDA’s concern regarding cell phones is that they could interfere with some medical devices. Courtesy of the FDA and YouTube)
In this latest study, the NTP looked at the effects of high exposure to radiofrequency energy in rodents.
It’s important to understand that – as is commonly done in these types of risk assessment studies – the study was designed to test levels of radiofrequency energy exposures considerably above the current safety limits for cell phones to help contribute to what we already understand about the effects of radiofrequency energy on animal tissue.
In fact, the current safety limits are set to include a 50-fold safety margin from observed effects of radiofrequency energy exposure.
From the FDA’s understanding of the NTP results, male rats that showed carcinogenic activity were exposed to a radiofrequency energy exposure rate that is much higher than the current safety standard.
As our colleagues at NTP note in a statement issued earlier today, “the levels and duration of exposure to radiofrequency radiation were much greater than what people experience with even the highest level of cell phone use, and exposed the rodents’ whole bodies. So, these findings should not be directly extrapolated to human cell phone usage.”
Looking at the results in animals, the conclusions still require careful discussion, as our preliminary understanding of the NTP results is that the study found mostly equivocal, or ambiguous, evidence that whole body radiofrequency energy exposures given to rats or mice in the study actually caused cancer in these animals.
There are additional unusual findings from the study, such as the exposed rats living longer than the control group rats, that we are assessing to understand how that may be relevant to the results.
The FDA looks forward to participating in the peer review of this study in March, which is an important and crucial step in scientific research to assure the integrity and quality of the data and the conclusions that can be drawn from it.
Public comment is welcome during this period and can be provided through the NTP’s Federal Register notice.
As part of our work to assess this important public health and consumer safety issue, the FDA has reviewed many sources of scientific and medical evidence related to the possibility of adverse health effects from radiofrequency energy exposure in both humans and animals and will continue to do so as new scientific data are published.
We have reviewed the 2016 interim NTP results and are currently reviewing the full set of data from the NTP draft final report.
The FDA will work quickly to thoroughly review the data and consider any impact of this work within the context of the full body of scientific evidence on this exposure.
In the meantime, I want to underscore that based on our ongoing evaluation of this issue and taking into account all available scientific evidence we have received, we have not found sufficient evidence that there are adverse health effects in humans caused by exposures at or under the current radiofrequency energy exposure limits.
Even with frequent daily use by the vast majority of adults, we have not seen an increase in events like brain tumors.
Based on this current information, we believe the current safety limits for cell phones are acceptable for protecting the public health.
The FDA, an agency within the U.S. Department of Health and Human Services, protects the public health by assuring the safety, effectiveness, and security of human and veterinary drugs, vaccines and other biological products for human use, and medical devices.
The agency also is responsible for the safety and security of our nation’s food supply, cosmetics, dietary supplements, products that give off electronic radiation, and for regulating tobacco products.
Statement from Jeffrey Shuren, M.D., J.D., director of the FDA’s Center for Devices and Radiological Health
High exposure to radiofrequency radiation linked to tumor activity in male rats
High exposure to radiofrequency radiation (RFR) in rodents resulted in tumors in tissues surrounding nerves in the hearts of male rats, but not female rats or any mice, according to draft studies from the National Toxicology Program (NTP).
The exposure levels used in the studies were equal to and higher than the highest level permitted for local tissue exposure in cell phone emissions today.
Cell phones typically emit lower levels of RFR than the maximum level allowed.
NTP’s draft conclusions were released on Friday, February 2, 2018 as two technical reports, one for rat studies and one for mouse studies.
NTP will hold an external expert review of its complete findings from these rodent studies March 26-28.
The incidence of tumors, called malignant schwannomas, that were observed in the heart increased in male rats as they were exposed to increasing levels of RFR beyond the allowable cell phone emissions.
Researchers also noted increases in an unusual pattern of cardiomyopathy, or damage to heart tissue, in exposed male and female rats.
Overall, there was little indication of health problems in mice related to RFR.
The reports also point out statistically significant increases in the number of rats and mice with tumors found in other organs at one or more of the exposure levels studied, including the brain, prostate gland, pituitary gland, adrenal gland, liver, and pancreas.
However, the researchers determined that these were equivocal findings, meaning it was unclear if any of these tumor increases were related to RFR.
“The levels and duration of exposure to RFR were much greater than what people experience with even the highest level of cell phone use, and exposed the rodents’ whole bodies,” said John Bucher, Ph.D., NTP senior scientist.
“So, these findings should not be directly extrapolated to human cell phone usage.”
“We note, however, that the tumors we saw in these studies are similar to tumors previously reported in some studies of frequent cell phone users.”
- To conduct the studies, NTP built special chambers that exposed rats and mice to different levels of RFR for up to two years.
- Exposure levels ranged from 1.5 to 6 watts per kilogram (W/kg) in rats, and 2.5 to 10 W/kg in mice.
- The low power level for rats was equal to the highest level permitted for local tissue exposures to cell phone emissions today.
- The animals were exposed for 10-minute on, 10-minute off increments, totaling just over 9 hours each day.
- The studies used 2G and 3G frequencies and modulations still used in voice calls and texting in the United States.
- More recent 4G, 4G-LTE, and 5G networks for streaming video and downloading attachments use different cell phone signal frequencies and modulations than NTP used in these studies.
The NTP studies also looked for a range of noncancer health effects in rats and mice, including changes in body weight, evidence of tissue damage from RFR-generated heating, and genetic damage.
Researchers saw lower body weights among newborn rats and their mothers, especially when exposed to high levels of RFR during pregnancy and lactation.
Yet, these animals grew to normal size.
“These studies were complex and technically challenging, but they provide the most comprehensive assessment, to date, of health effects in rats and mice from exposure to RFR,” said Bucher.
“Cell phone technologies are constantly changing, and these findings provide valuable information to help guide future studies of cell phone safety.”
The U.S. Food and Drug Administration nominated cell phone radiofrequency radiation for study by NTP because of widespread use of cell phones. FDA and the Federal Communications Commission are jointly responsible for regulating wireless communication devices.
The National Toxicology Program (NTP), is a federal, interagency program headquartered at NIEHS, whose goal is to safeguard the public by identifying substances in the environment that may affect human health.
The National Institute of Environmental Health Sciences (NIEHS), supports research to understand the effects of the environment on human health and is part of NIH.
The National Institutes of Health (NIH), the nation’s medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services.
NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases.
If there is a risk from being exposed to radiofrequency energy (RF) from cell phones–and at this point we do not know that there is–it is probably very small.
But if you are concerned about avoiding even potential risks, you can take a few simple steps to minimize your RF exposure.
- Reduce the amount of time spent using your cell phone
- Use speaker mode or a headset to place more distance between your head and the cell phone.
- Hand-free kits may include audio or Bluetooth headsets and various types of body-worn accessories such as belt-clips and holsters.
- Combinations of these can be used to reduce RF energy absorption from cell phone.
- Headsets can substantially reduce exposure since the phone is held away from the head in the user’s hand or in approved body-worn accessories.
- Cell phones marketed in the U.S. are required to meet RF exposure compliance requirements when used against the head and against the body.
- Since there are no known risks from exposure to RF emissions from cell phones, there is no reason to believe that hands-free kits reduce risks.
- Hands-free kits can be used for convenience and comfort.
- They are also required by law in many states if you want to use your phone while driving.
Cell phone accessories that claim to shield the head from RF radiation
- Since there are no known risks from exposure to RF emissions from cell phones, there is no reason to believe that accessories that claim to shield the head from those emissions reduce risks.
- Some products that claim to shield the user from RF absorption use special phone cases, while others involve nothing more than a metallic accessory attached to the phone.
- Studies have shown that these products generally do not work as advertised.
- Unlike “hand-free” kits, these so-called “shields” may interfere with proper operation of the phone.
- The phone may be forced to boost its power to compensate, leading to an increase in RF absorption.