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.
"For example," Johnson said, "what does a fractal like pattern have to do with a hologram? The answer is, of course, nothing that is apparent. Then there is a truly convoluted assertion that cell phones can be instrumental in ‘psychoemotional' effects on humans because of their lower-frequency outputs. This too, is gibberish. In short, this is technobabble that will potentially snow someone who has no science background."
One of the studies reports that male rats exposed to very high levels of radiofrequency radiation grew tumors around their hearts. Female rats exposed to the radiation didn’t, and neither male nor female mice showed obvious health problems in a second study. Neither study turned up clear evidence that radiofrequency radiation causes brain tumors, although the researchers are continuing to investigate. The studies are drafts that haven’t yet been reviewed by outside scientists.
These experimental findings raise new questions as to the potential for radiofrequency radiation to result in cellular changes and offer potential avenues for further laboratory studies. Cancers in the heart are extremely rare in humans, where the primary outcomes of potential concern with respect to radiofrequency radiation exposure from cell phones are tumors in the brain and central nervous system. Schwann cells of the heart in rodents are similar to the kind of cells in humans that give rise to acoustic neuromas (also known as vestibular schwannomas), which some studies have suggested are increased in people who reported the heaviest use of cell phones. The NTP has stated that they will continue to study this exposure in animal models to further advance our understanding of the biological underpinnings of the effects reported above.
Most cellphone shielding products are designed to reduce radiation to the user while still allowing the phone to function. This means that some radiation can still get to the phone… and some radiation can still get out of the phone! But sometimes you need to completely kill the signal. The RF Kill Box is a full-metal shielding jacket with very high shielding performance.
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.
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.
There are theoretical considerations as to why the possible risk should be investigated separately in children. Their nervous systems are still developing and, therefore, more vulnerable to factors that may cause cancer. Their heads are smaller than those of adults and consequently have a greater proportional exposure to the field of radiofrequency radiation that is emitted by cell phones. And, children have the potential of accumulating more years of cell phone exposure than adults do.

The Specific Absorption Rate test uses sophisticated instruments to measure the amount of radiation absorbed into the body, usually the head. At present, the generally recognized limit for absorbed electromagnetic energy is 1.6 watts per kilogram. All cell phones sold must be tested and have their compliance with this standard certified by their manufacturer. The electromagnetic fields from a cell phone depend upon the design of the cell phone and its antenna,how it operates, as well as how it is held and used. Tests conducted by the ABC show 20/20 has found that some of the country’s most popular cell phones can – depending on how they’re held – exceed the radiation limit. A cell phone’s antenna radiates in all directions. The health concern is about the radiation actually absorbed into the head, which is where cell phones are usually held. SAR tests conducted on the SAR Shield show that the product reduces SAR radiation by as much as 89%.
What the study showed: Most published analyses from this study have shown no statistically significant increases in brain or central nervous system cancers related to higher amounts of cell phone use. One analysis showed a statistically significant, although modest, increase in the risk of glioma among the small proportion of study participants who spent the most total time on cell phone calls. However, the researchers considered this finding inconclusive because they felt that the amount of use reported by some respondents was unlikely and because the participants who reported lower levels of use appeared to have a slightly reduced risk of brain cancer compared with people who did not use cell phones regularly (4–6).
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