All iPhone 12 models should be kept at a safe distance from individuals with pacemakers or defibrillators, according to a new warning issued to Apple customers in a support document on the company's website.
Apple noted that its iPhones and MagSafe accessories contain magnets and radios that emit electromagnetic fields that "might interfere with medical devices."
"Though all iPhone 12 models contain more magnets than prior iPhone models, they're not expected to pose a greater risk of magnetic interference to medical devices than prior iPhone models," the company added. "Medical devices such as implanted pacemakers and defibrillators might contain sensors that respond to magnets and radios when in close contact."
Apple is advising that customers keep iPhones and compatible MagSafe accessories at least six inches away from pacemakers and defibrillators during normal use and at least 12 inches away when wirelessly charging.
Customers should consult with their physician and medical device manufacturer for specific guidelines.
The warning comes following a study by the Heart Rhythm Journal earlier this month which claimed that the magnets in iPhone 12 models caused a patient's implantable cardioverter defibrillator (ICD) from Medtronic to be suspended when the smartphone was held directly over them.
"Once the iPhone was brought close to the ICD over the left chest area, immediate suspension of ICD therapies was noted which persisted for the duration of the test," researchers wrote. "This was reproduced multiple times with different positions of the phone over the pocket."
However, the study was only carried out on one person and didn't show if the same result would have occurred with a non-MagSafe device.
Medtronic issued its own statement noting that after analyzing the iPhone 12, the company found that the smartphone's technology "presents no increased risk of interference with Medtronic implantable cardiac rhythm devices, such as pacemakers, implantable defibrillators (ICDs), and cardiac resynchronization therapy defibrillators (CRT-Ds), when used according to labeling."
"A recently published study did not follow this advice or the approved labeling for these devices in their methodology. When used as directed, there is no increased risk of interference," Medtronic said. "To protect our patients, we have built safeguards into Medtronic implantable cardiac devices to allow for normal daily interference; these safeguards include electronic filters that distinguish between natural heartbeat signals and other potential interference."
Like Apple, Medtronic recommends patients implanted with cardiac devices to maintain a safe distance of at least six inches between all cell phones and their implanted devices, consistent with recommendations for other low wattage electromagnetic devices.