Following concerns that Apple’s iPod posed a health threat to pacemaker users, the Food and Drug Administration conducted its own study into the safety of the portable media player. The verdict: The iPod poses no threat to pacemaker patients, according to ScienceDaily.

The study led by FDA researcher Howard Bassen measured the magnetic fields generated by a fourth generation iPod, a video-capable iPod, an iPod nano, and an iPod shuffle along with the voltages each device delivered to cardiac pacemakers. The results indicated that there are no effects on pacemaker patients from the iPods.

In May 2007, a different report spawned from a high school student’s research stated that portable media players, including Apple’s iPod, caused pacemaker malfunctions in 50 percent of patients. Doctors involved in the earlier research found that an iPod held two inches from a patient’s chest resulted in pacemaker telemetry interference about 29 percent of the time.

Mr. Bassen’s study, however, appears to be more detailed and showed that at distances between five and ten millimeters from a pacemaker, an iPod output a peak magnetic field strength of 0.2 millionths of a Tesla -- far below the levels necessary to interfere with a pacemaker.

Mr. Bassen commented "Based on the observations of our in-vitro study we conclude that no interference effects can occur in pacemakers exposed to the iPods we tested."