The Environmental Working Group, a lobbying non-profit orgainisation, has published a list detailing the amount of radiated energy coming from over 1,000 mobile devices.

The Cellphone Radiation list shows that Motorola produces five of the top 10 radiation-emitting phones. The Motorola Moto VU204 heads the list, followed by T-Mobile's myTouch 3G and Kyocera's Jax S130.

By contrast, Samsung had five phones of the top six least-emitting handsets. The Samsung Impression came first, followed by the Motorola Razr V8 and the Samsung SGH-t229.

"We would like to be able to say that cell phones are safe, but we can't," said Olga Naidenko, senior scientist at the Environmental Working Group and lead author of the study.

"The most recent science, while not conclusive, raises serious issues about the cancer risk of cell phone use that must be addressed through further research. In the meantime, consumers can take steps to reduce exposure."

The group called for manufacturers to label all phones with the radiation levels they emit at the point of sale.

The jury is still out on the health hazards or otherwise of using mobile phones. While health claims have been made that mobiles cause harm to humans and others, different studies by manufacturers and academics have shown otherwise.