In 2011, researchers at the National Institutes of Health showed that low-level radiation from an activated cell phone held close to a human head could change the way certain brain cells functioned, even without raising body temperature. The study did not prove that the effect on brain cells was dangerous, only that radiation from cell phones could have a direct effect on human tissue.
A phone's specific absorption rate (SAR) reveals the maximum amount of radiation the human body absorbs from the phone while it's transmitting. SAR testing ensures that the devices sold in the U.S. comply with the Federal Communications Commission (FCC) SAR exposure limit, but the single, worst-case value obtained from this SAR testing is not necessarily representative of the absorption during actual use, and therefore it is not recommended for comparisons among phones. In short, selecting a lower SAR phone will not reliably ensure lower radiation absorption during use. The FCC has more information at Specific Absorption Rate (SAR) For Cell Phones: What It Means For You.

The BlocSock is a small, 3”x5½”, lightweight case that's only designed for cell phones, not tablets or laptops. One side is a normal fabric to ensure reception. The other side has a rectangular, metallic mesh to shield RF radiation. It's recommended that you keep the side with the shielding material between the phone and your body. When making or receiving calls, keep the shielding between your head and the phone. It can also be moved into a smaller “kangaroo style” pouch during calls. It's effective, and tests show that it reduces RF exposure 96%. For more information, check out the SAR research test or watch this video.
Want to let people know that cellphones cannot be used in certain areas without an embarrassing confrontation? These decals are suitable for putting up in schools, restaurants, theaters, stores, taxicabs, busses, trains, hospitals, offices, homes or any other place that's appropriate for a cellphone-free zone. High quality decals measure 3½" by 3½". Nice strong adhesive, simply peel and stick.
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.
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.”

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 exposures used in the studies cannot be compared directly to the exposure that humans experience when using a cell phone,” John Bucher, a senior scientist at the NTP, a government program within the department of Health and Human Services, says in a press release. “In our studies, rats and mice received radio frequency radiation across their whole bodies. By contrast, people are mostly exposed in specific local tissues close to where they hold the phone. In addition, the exposure levels and durations in our studies were greater than what people experience.”

It’s easy to call any case a product designed to block smartphone radiation.  What you need to look for is credible, quantifiable claims that highlight a case’s ability to reduce your exposure to the harmful radiation. Look for relevant  certifications from credible organizations (such as FCC accredited laboratories) that will vouch for product claims, and read product reviews online.
“The exposures used in the studies cannot be compared directly to the exposure that humans experience when using a cell phone,” John Bucher, a senior scientist at the NTP, a government program within the department of Health and Human Services, says in a press release. “In our studies, rats and mice received radio frequency radiation across their whole bodies. By contrast, people are mostly exposed in specific local tissues close to where they hold the phone. In addition, the exposure levels and durations in our studies were greater than what people experience.”
“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:
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.
Specific Absorption Rate is an indicator of how much EMF radiation body tissue absorbs when you’re using a cell phone and is one way to measure and compare the harm of different devices. In this article, I wanted to provide a resource to compare and contrast the SAR levels of many popular phones and talk a bit about what Specific Absorption Rate is, and how we can use it.

As to increases in brain tumors tied to cell phone use, it’s too early to tell due to a lack of hard data, says Dr. Carlo. “We’re never going to see that in time to have it matter. Here in the US, we’re six years behind in getting the brain tumor database completed, and currently the best data are from 1999. By the time you see any data showing an increase, the ticking time bomb is set.”
But there’s a huge public health crisis looming from one particular threat: EMR from cellular phones—both the radiation from the handsets and from the tower-based antennas carrying the signals—which studies have linked to development of brain tumors, genetic damage, and other exposure-related conditions.1-9 Yet the government and a well-funded cell phone industry media machine continue to mislead the unwary public about the dangers of a product used by billions of people. Most recently, a Danish epidemiological study announced to great fanfare the inaccurate conclusion that cell phone use is completely safe.10
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.

Jump up ^ Repacholi MH, Lerchl A, Röösli M, Sienkiewicz Z, Auvinen A, Breckenkamp J, d'Inzeo G, Elliott P, Frei P, Heinrich S, Lagroye I, Lahkola A, McCormick DL, Thomas S, Vecchia P (2012). "Systematic review of wireless phone use and brain cancer and other head tumors". Bioelectromagnetics (Systematic review). 33 (3): 187–206. doi:10.1002/bem.20716. PMID 22021071.
The phone is placed in various positions on the head and body, including held to both ears, and all measurements are taken and reported to the FCC when the manufacturer is seeking approval. However, it should be noted that only the very highest SAR values for each type of radiation are included in final consideration for compliance with the FCC’s guidelines.

Unfortunately, however, we’ll probably never have an RCT on cellphones and cancer in humans. It’d be too difficult and too expensive to randomly assign particular levels of cellphone use to thousands of people and have them stick with those plans for enough time (we’re talking at least five years) to figure out whether certain types of phones or phone use patterns cause cancer to develop. That’s not to mention the fact it’d be nearly impossible to find a group of people willing to not use cellphones and then make sure they actually stick to their promise.
The researchers found other strange effects that muddied the interpretation of the studies: The rats exposed to cellphones seemed to outlive the rats in the control group, for example. There was no clear linear relationship between higher levels of cellphone exposure and more cancer at some tissue sites, and the cancer rate in the control group was lower than it should have been at other tissue sites.
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.

How many times do you put your cell phone in your back pocket when dashing to work or to a meeting? Maintaining a close proximity of cell phones to reproductive organs may not be the wisest idea when it comes to protecting reproductive health. SYB (Shield Your Body) Pocket Patch is a thin, white, and extremely lightweight patch that can be easily ironed on to the inside of pockets, effectively reducing up to 99% of cell phone radiation. Despite the powerful radiation-blocking effects of the hypoallergenic patch, it doesn't interfere with your phone's battery life or its normal behavior. It can be easily ironed on to any fabric, and tests show that the SYB maintains its potency even after 30 washes. Each patch is 5.5" tall and 3.75" wide, perfect for basic pockets in most pants, sweaters, and jackets.

We began by getting a baseline of ambient RF in the room at the location of our testing. We then recorded a baseline of the cellphone RF while on an active call with no case. And finally, we measured the reduction in that baseline (still on the active call) using a variety of different cases and RF reducing products – all at the same set distance from the phone.
So of course now that we understand that the cases are not tested and just the material--it makes sense! We measured power density levels all around the case-the shielding material most likely isn't used "all over" because then the phone couldn't receive signal and wouldn't be able to engage in a call.  That's why we did not see even close to a 99% reduction when some cases were on the phone.  In fact, watch the video and you'll see some readings are more than 20% higher with a case on vs the naked phone.
The NTP studied radiofrequency radiation (2G and 3G frequencies) in rats and mice (33, 34). This large project was conducted in highly specialized labs that specified and controlled sources of radiation and measured their effects. The rodents experienced whole-body exposures of 3, 6, or 9 watts per kilogram of body weight for 5 or 7 days per week for 18 hours per day in cycles of 10 minutes on, 10 minutes off. A research overview of the rodent studies, with links to the peer-review summary, is available on NTP website. The primary outcomes observed were a small number of cancers of Schwann cells in the heart and non-cancerous changes (hyperplasia) in the same tissues for male rats, but not female rats, nor in mice overall.