iPhone city San Francisco is first in U.S. to demand radioactivity warnings on mobiles

The home city of the iPhone has passed a law requiring warning radioactivity warning labels on new mobiles.

San Francisco retailers will soon have to provide information on the specific absorption rate (SAR) of all handsets stocked.

Repeat with me: “Radiation” and “radioactive” are not the same thing.
The specific absorption rate in question is of radiofrequency radiation, which is non-ionizing, and in no way implies that the source is radioactive (i.e. comes from a spontaneous nuclear reaction), because it doesn’t.

On the other hand, it’s the Daily Mail. They apparently handle science no better than Robert Green handles weak shots-on-goal by Americans. (Bang!)

As far as the legislation goes, I think it’s antiscience being sold as informing consumers. But what information is being provided? I think specific absorption rate is being abused here, because it’s not being explained. If I have a mass of 100 kg, does a phone with an SAR of 1.6W/kg mean it is emitting 160 Watts? And for a user who has a mass of 70 kg, the power magically drops to 112 Watts? No. SAR is measured using a calibration standard of one gram of tissue (in the US; in Europe it’s 10 grams) meaning the gram of tissue absorbs 1.6 milliwatts of radiation from the source, under some geometry. The actual power emitted by a cellphone is of order a Watt. But even that information is almost useless without context; the human body radiates somewhere around 800-900 Watts in a more-or-less blackbody spectrum. Is that a cause for concern?