CTIA, the wireless industry lobbying association, disagrees. In a statement it noted that "scientific evidence has overwhelmingly indicated that wireless devices do not pose" a health hazard.

That's why the American Cancer Society, World Health Organization and Food and Drug Administration, among others, "all have concurred that wireless devices are not a public health risk," the CTIA statement says.

Houlihan acknowledges that "the verdict is still out" on whether cellphones can be linked directly to cancer.

"But there's enough concern that the governments of six countries" — including France, Germany and Israel — "have issued limits of usage of cellphones, particularly for children."

Houlihan says her group is "advising people to choose a phone that falls on the lower end of the (radiation) spectrum" to minimize potential health problems. The Samsung Impression has the lowest: 0.35 watts per kilogram, a measure of how much radiation is absorbed into the brain when the phone is held to the ear.

The highest: T-Mobile's MyTouch 3G, Motorola Moto VU204 and Kyocera Jax S1300, all at 1.55 W/kg.

The Apple iPhone, sold exclusively by AT&T in the USA, is in the middle of the pack at 1.19 W/kg.

The Federal Communications Commission, which sets standards for cellphone radiation, requires that all devices be rated at 1.6 W/kg or lower.

The Environmental Working Group says the FCC's standard is outmoded, noting that it was established 17 years ago, when cellphones and wireless usage patterns were much different. The group wants the government to take a "fresh look" at radiation standards.

The FCC currently doesn't require handset makers to divulge radiation levels. As a result, radiation rankings for dozens of devices, including the BlackBerry Pearl Flip 8230 and Motorola KRZR, aren't on the group's list.