Still, despite the odds, these fears could be around for a while — because it’s hard to prove that cellphone radiation doesn’t cause harm. There are just too many combinations of genes, environmental exposures, patterns of cellphone use, plus a healthy helping of random chance to consider. It’s why we’re still having the conversation about whether coffee, for example, is good or bad for us. So while the bulk of evidence points to no health effects from cellphone radiation, the scientific literature is still somewhat mixed, Foster says. “Someone who wants to worry can pick and choose and find a lot of evidence that would support their theories.”

Most of these early studies did not find an increase in the risk for developing tumors among mobile phone users. The main problem characterizing these studies stems from the fact that the development of cancer (in particular brain tumors) takes a very long time (at least 10-20 years and up to 40 years or more), while mobile phone technology is relatively new (as aforesaid, popular use began only in the mid-90s). Hence, these studies could not demonstrate risk even if such existed.
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.
“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.”

The device comes in a variety of forms ranging from the $39 Aries Shield ("a silicon based micro processor that ... decomposes oscillations of electromagnetic fields") to the $249 Aires Defender Utility (which "has two next generation 9 core silicon based micro processor (sic) that provide universal protection from electromagnetic smog of the broadband frequencies").

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.”
“One thing all these conditions have in common is a disruption, to varying degrees, of intercellular communication. When we were growing up, TV antennas were on top of our houses and such waves were up in the sky. Cell phones and Wi-Fi have brought those things down to the street, integrated them into the environment, and that’s absolutely new. The recognition mechanism, where protein vibration sensors on the cell membrane pick up a signal and interpret it as an invader, only works because the body recognizes something it’s never seen before.”
Our homemade demonstration of all the cases uses a working phone. Not the shielding material by itself, but the actual "shielding" SafeSleeve, Pong, Reach,  Vest, ShieldMe, and Defender Shield cases. First we get RF power density measurements from a phone that's on a call and then, in the same location, within minutes of the first reading, we place the same phone as it's engaged in a call into each case and we take additional reading with the meter.
I love this case. However, I don't understand what happens to the radiation that must collect under the case; isn't there a burst of radiation when the case is opened? I posted this question but the answers were from people who hadn't thought of that issue; they didn't have the answer, except for one who theorized that the radiation is slowly leaking out the top, bottom, and sides. I assume the case keeps radiation off the hand that holds the case with the phone in it, which is great, but I do wonder about the stored radiation when, for example, I'm listening to a podcast with the case closed, then open it later.
Dr. Carlo and his team developed new exposure systems that could mimic head-only exposure to EMR in people, as those were the only systems that could approximate what really happened with cell phone exposure. Those exposure systems were then used for both in vitro (laboratory) and in vivo (animal) studies. The in vitro studies used human blood and lymph tissue in test tubes and petri dishes that were exposed to EMR. These studies identified the micronuclei in human blood, for example, associated with cell phone near-field radiation. The in vivo studies used head only exposure systems and laboratory rats. These studies identified DNA damage and other genetic markers.
Homeopathic remedies, credit cards and passports with chips, and electronic equipment can all be compromised by exposure to electromagnetic fields. The EMP Can™ is a great air-tight way to store these items and protect them from outside EMF influences including low grade EMP. Shields both radiofrequency and magnetic fields by 95% or more. All metal construction, nice wide mouth and quick-close latch keep contents secure.

We used a few measuring devices to test and see if this product actually blocks radiation and RFID, including a very sophisticated EMF reader. I am glad to say that this is actually a very effective way to reduce radiation. It is most effective on the front side, and when you have it closed and latched, there is very little exposure - only along the top, side and bottom opening.

I liked the way Blocsock implemented this protection and the quality of the product construction, combined with the validated test results, so I recently ordered ones for the rest of my family. I think Blocsock is the BMW-class of what I could find for products that protect against cell phone radiation. My wife has a larger Droid phone and it fits in the case (just barely though)! I hope the makers consider making a larger model for all the new, larger smartphones that recently came out with the larger screen sizes. Again, check to make sure your phone fits, which a friendly message to the company will answer if you are not sure.

The government’s policies must change. Cell phone users should make their voices heard to prompt the FCC and manufacturers of cell phones and cases to ensure that these accessories never increase and, to the extent possible, decrease, users’ radiation exposure. At minimum, the FCC must take cell phone cases into consideration when it updates its standards to ensure that the use of a case will not expose people to more radiation than its legal SAR limit.  
The base station is equipped with antennas for reception and transmission. In order to communicate, the mobile phones and the antennas at the base station emit radiowave radiation (see below). The mobile phone instrument transmits a lower amount of radiation than the one transmitted by the transmission center (cell site), but because the instrument is near the body, the body directly absorbs the energy from the instrument’s antenna.
As a rule, modern medical equipment is well protected against exposure to radiowave radiation. Therefore, there is generally no need for concern regarding the effects of mobile phones on the normal function of the equipment. Nevertheless, the Ministry of Health recommends not to have a mobile phone in the immediate proximity (a distance of 30-50 cm from the portable medical equipment or from medical equipment implanted in the patient's body).
Most of these early studies did not find an increase in the risk for developing tumors among mobile phone users. The main problem characterizing these studies stems from the fact that the development of cancer (in particular brain tumors) takes a very long time (at least 10-20 years and up to 40 years or more), while mobile phone technology is relatively new (as aforesaid, popular use began only in the mid-90s). Hence, these studies could not demonstrate risk even if such existed.

Unfortunately, regulatory boards do not require third-party phone accessory manufacturers to consider how their product will work in tandem with the smartphone. Neither do governments require smartphone manufacturers to conduct extensive research on whether their SAR will still meet the FCC’s allowable radiation exposure limits when their devices are using a phone case or other 3rd party accessories.
When it comes to ionizing radiation — which we’re exposed to in X-rays, in CT scans, and during air travel — we know it’s powerful enough to damage the DNA, and that repeated DNA damage over time can cause cancer. That’s why, for example, you’re not supposed to get too many X-rays in your lifetime. (In case you were wondering, there’s no precise number on how many X-rays are too many — but the Food and Drug Administration suggests keeping track and avoiding any that seem unnecessary.)

In 2011, two small studies were published that examined brain glucose metabolism in people after they had used cell phones. The results were inconsistent; whereas one study showed increased glucose metabolism in the region of the brain close to the antenna compared with tissues on the opposite side of the brain (26), the other study (27) found reduced glucose metabolism on the side of the brain where the phone was used.