Could your cell phone be killing you? A lot of people seem to think so. Some activists say that talking on your phone for 30 minutes a day over several years can cause brain tumors. They say governments need to address the problem with regulations. The alternative? “[D]o nothing and wait for the body count,” according to the University of Albany’s  David Carpenter.

Regulations are starting to pass. San Francisco just passed a law requiring cell phone retailers to disclose how much radiation their products emit. The city already has a warning label regulation. Maine passed its own warning label mandate last year.

Now Rep. Dennis Kucinich (D-OH) is introducing federal labeling legislation, so that “cell phone users can decide for themselves the level of risk that they will accept.”

Fortunately, when it comes to cell phones and cancer, that risk is zero. It is physically impossible for cell phones to cause cancer. Literally. Most phones only emit about one watt of energy. The legal limit is 1.6 watts. This is not nearly enough to cause the tissue damages that cause many kinds of cancer.

How little energy is one watt? The human body generates about a hundred times that much energy during normal, everyday activity. During exercise, our bodies can pump out more than 1,100 watts of energy – enough to power a whole row of light bulbs. Adding a single watt to that baseline does nothing to contribute to the DNA damage that can lead to tumor growth.

So if scare-mongerers are right that one-watt cell phones can cause brain tumors, they should be at least a thousand times more worried about working out. But they aren’t. Suspicious.

There’s more. Not only are cell phones too weak to cause tissue damage, they don’t even operate at the right frequency to do so. Some frequencies are dangerous to living tissue. Others aren’t. The sun’s visible light is harmless to humans. But its higher-energy UV rays have caused countless cases of skin cancer among the sun-bathing set.

The physicist Bernard Leikind found that cell phone photons are so weak, they fall short of DNA-damaging energy levels by about a factor of 500,000.

So you might have something to worry about if you strapped half a million cell phones to your body. But it wouldn’t be cancer – it would be getting crushed to death. So talk on your phone all you want. Unless you’re driving while you’re gabbing, you are safe.

The cell phone cancer scare probably says more about the people promoting it than anything else. Activists promoting the scare only ever mention brain tumors. And brain tumors are frightening. But you hold your cell phone in your hand. You hold it next to your ear and your jaw. Why no mention of those cancers?

They should be just as worried about skin and bone cancers in the hand. They should also be worried about the ears and the jaws. Not to mention the scalp and skull that take in every bit as much cell phone radiation as the brain. This strangely selective choice of scare-mongering is reason to be suspicious of the phone-cancer connection. Some people just like to be scared. And other people can get massive amounts of funding by catering to those people.

So don’t buy into the hype. David Carpenter and Dennis Kucinich can live in bed-wetting fear of their phones if they like. But you don’t have to.

Ryan Young is the Warren T. Brookes Journalism Fellow at the Competitive Enterprise Institute in Washington, D.C.