In March, however, a peer-review panel of 11 experts from industry and academia voted to advise the agency that it should raise the confidence level from “equivocal evidence” to “some evidence” of a link between cellphone radiation and brain tumors in male rats. (The female rats did not show evidence of a link between the radiation and such tumors.) Two panel members, Lydia Andrews-Jones of Allergan and Susan Felter of Procter & Gamble, proposed the risk upgrade.

There are few if any references to actual studies in published, peer-reviewed journals that support the claim that Aires, or any other, cell phone shield actually works. The "Researches" page contains a superficially impressive list of sciencey-sounding titles and findings supposedly demonstrating the importance of using cell phone shields, all of them in Russia for some reason.

Since speaking with Samet, further details came out from a large study that beamed high levels of phone radiation at rats and mice. While there remain quirks in the findings, the latest evidence still doesn’t find a link between phone radiation and cancer. In response, the FDA said, “Taken together, all of this research ... [has] given us the confidence that the current safety limits for cell phone radiation remain acceptable for protecting the public health.”

But scientists disagree on how real—or how serious—these risks really are, and studies have not established any definitive links between health problems and radiofrequency (RF) energy, the type of radiation emitted by cell phones. “This document is intended to provide guidance for people who want to reduce their own and their families’ exposure to RF energy from cell phones,” the guidelines state, “despite this uncertainty.”

The frequency of radiofrequency electromagnetic radiation ranges from 30 kilohertz (30 kHz, or 30,000 Hz) to 300 gigahertz (300 GHz, or 300 billion Hz). Electromagnetic fields in the radiofrequency range are used for telecommunications applications, including cell phones, televisions, and radio transmissions. The human body absorbs energy from devices that emit radiofrequency electromagnetic radiation. The dose of the absorbed energy is estimated using a measure called the specific absorption rate (SAR), which is expressed in watts per kilogram of body weight.