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.
But according to the FCC, comparing SAR values between phones can be misleading. The listed SAR value is based only on the phone operating at its highest power, not on what users would typically be exposed to with normal phone use. The actual SAR value during use varies based on a number of factors, so it’s possible that a phone with a lower listed SAR value might actually expose a person to more RF energy than one with a higher listed SAR value in some cases.
The 13-country INTERPHONE study, the largest case-control study done to date, looked at cell phone use among more than 5,000 people who developed brain tumors (gliomas or meningiomas) and a similar group of people without tumors. Overall, the study found no link between brain tumor risk and the frequency of calls, longer call time, or cell phone use for 10 or more years. There was a suggestion of a possible increased risk of glioma, and a smaller suggestion of an increased risk of meningioma, in the 10% of people who used their cell phones the most. But this finding was hard to interpret because some people in the study reported implausibly high cell phone use, as well as other issues. The researchers noted that the shortcomings of the study prevented them from drawing any firm conclusions, and that more research was needed.
Searching PubMed for studies published in the past 10 years, we found 102 studies that ultimately resulted in 12 relevant systematic reviews. To limit bias in our assessment of the literature, we used a validated critical appraisal tool called AMSTAR to determine the quality of each review. Eight of the reviews were critically low quality, two were low quality, and two were moderate quality.
Regular battery-powered watches (and all other battery-powered tech, for that matter) also produce some level of EMFs, but that level is far lower than the amount emitted by tech devices that are plugged in, or that receive and transmit information wirelessly. The same rule applies however; if you can turn it off and keep it away from your body, then do so whenever possible.
However, there have been some studies that have shown that rats can develop a specific type of brain tumor, called a schwannoma, if they're subjected to prolonged radiofrequency radiation. These studies examined thousands of rats and mice, and exposed them to a variety of radiations — everything from "near-field" (which is what you get holding a phone to your ear) to "far-field" (which is what you get walking through everyone's Wi-Fi signals at Starbucks).
A 2010 review stated that "The balance of experimental evidence does not support an effect of 'non-thermal' radiofrequency fields" on the permeability of the blood-brain barrier, but noted that research on low frequency effects and effects in humans was sparse. A 2012 study of low-frequency radiation on humans found "no evidence for acute effects of short-term mobile phone radiation on cerebral blood flow".
Read the “fine print” from the manufacturer’s instruction manual which tells users to put a distance between the phone and your head and body. These fine print warnings range from a few millimeters to almost an inch. The fine print warnings on other wireless devices (such as Wi-Fi routers, wireless printers, home cordless phone base stations and baby monitors) generally state the distance should be at least 20 cm, or about 8 inches. If people are closer than the manufacturer stated separation distance, then they can be exposed to RF levels that violate the US government FCC limits for this radiation.
In the US, a small number of personal injury lawsuits have been filed by individuals against cellphone manufacturers (including Motorola, NEC, Siemens, and Nokia) on the basis of allegations of causation of brain cancer and death. In US federal courts, expert testimony relating to science must be first evaluated by a judge, in a Daubert hearing, to be relevant and valid before it is admissible as evidence. In a 2002 case against Motorola, the plaintiffs alleged that the use of wireless handheld telephones could cause brain cancer and that the use of Motorola phones caused one plaintiff's cancer. The judge ruled that no sufficiently reliable and relevant scientific evidence in support of either general or specific causation was proffered by the plaintiffs, accepted a motion to exclude the testimony of the plaintiffs' experts, and denied a motion to exclude the testimony of the defendants' experts.
The reason we’re talking about cellphones and cancer — why there’s a concern here — is because they emit radiation, the invisible waves of electric and magnetic energy, of varying power, organized on the electromagnetic spectrum. You can see in the graphic below that less powerful (or lower-frequency) types of radiation are on the left, moving to the more powerful (or higher-frequency) types of radiation on the right.
I purchased two different color cases and I was surprised when I received it because the inner case was different than described in some of the reviews. But when I looked at the Amazon listing, I didn’t realize that the case has been updated and I’m pleasantly surprised. The inner case is a soft, flexible plastic that doesn’t seem like it would break at all. I borrowed an EMF reader from a friend and the case works as described. I’m very happy with the cases and I’m glad that I purchased one for my boyfriend too! I definitely recommend this case!
What the study showed: Self-reported cell phone use was not associated with an increased risk of glioma, meningioma, or non-central nervous system tumors. Although the original published findings reported an association with an increased risk of acoustic neuroma (14), this association disappeared after additional years of follow-up of the cohort (15).