For patients with pacemakers, headphones might pose as a significant health risk, reveals a new study.

According to Kevin Fu at the University of Massachusetts Amherst, while they are safe to use, keeping them in breast pockets might interfere with working of the implanted device.

In the study involving 100 people, nearly a third of cases showed that the magnets interfered with the device, reports New Scientist magazine.

Fu and colleagues tested eight different headphones by holding them near the implants.

Fu also revealed that headphones containing neodymium were the most problematic, as the magnetic fields generated were very strong for the headphones size.