New research could affect the 90-million Americans that use cell phones. Do the phones really pose a health risk?

The new research is funded by the cell phone industry but conducted by FDA scientists. They want conclusive evidence about whether cell phones affect human health.

You see them just about everywhere. But can what you don't see hurt you?

Low-level radiation emitted from cell phones, just inches from the brain. So far, industry studies have raised questions about potential effects on human cells.

Jo-Anne Basile/Cellular Telecommunications Industry Association: "What they saw was a change in the cell based on an exposure to radio frequencies."

But no evidence of actual harm. Another finding: A potential link between mobile phone use and a particular type of brain cancer. Still, nothing conclusive.

There are the hands-free sets, keeping radio frequencies far from the head. But some industry analysts say current research offers all cell phone users reason to feel safe.

Herschel Shostech/Industry Analyst: "It is very clear that there is far more, far more of these radio emissions in the environment today than there were 50 years ago. But at the same time, people are living longer than they were 50 years ago."

The research will try to conclude whether the same devices that have freed millions of Americans from phone cords have a signal that causes detectable damage.