Researchers call for greater caution, but skeptics say the evidence from rat studies is not convincing

Does cell phone radiation cause cancer? New studies show a correlation in lab rats, but the evidence may not resolve ongoing debates over causality or whether any effects arise in people.

The ionizing radiation given off by sources such as x-ray machines and the sun boosts cancer risk by shredding molecules in the body. But the non-ionizing radio-frequency (RF) radiation that cell phones and other wireless devices emit has just one known biological effect: an ability to heat tissue by exciting its molecules.

Still, evidence advanced by the studies shows prolonged exposure to even very low levels of RF radiation, perhaps by mechanisms other than heating that remain unknown, makes rats uniquely prone to a rare tumor called a schwannoma, which affects a type of neuron (or nerve cell) called a Schwann cell.