AP
FILE - In this Thursday, Oct. 11, 2012 file photo, a pedestrian talking on a cellphone is silhouetted in front of a fountain at John F. Kennedy Plaza, also known as Love Park in Philadelphia. Released on Friday, Feb. 2, 2018, two government studies that bombarded rats and mice with cellphone radiation found a weak link to some heart tumors, but the research does not provide any clear answers about the safety of the devices that seem like extensions of our bodies. (AP Photo/Matt Rourke)