Radiofrequency radiation emitted from popular smartphones like iPhone 7 and Samsung Galaxy S8 is more than double over the legal safety limit set by the US regulators, a Chicago Tribune investigation reveals.

The Federal Communications Commission, which regulates phones emission, cleared the devices for the sale, on its website it states that the device “will never exceed” the maximum allowable exposure limit, which is harmful to humans.

“We take seriously any claims on non-compliance with the RF (radiofrequency) exposure standards and will be obtaining and testing the subject phones for compliance with FCC rules,” agency spokesman Neil Grace said.

The test was sponsored by the Tribune and conducted as per the federal guidelines at an accredited lab.

A year ago, the Tribune set out an important question to explore: Are cellphones as safe as manufacturers and government regulators say?

The Tribune tested 11 cellphones by measuring how much radiofrequency radiations were absorbed by the human body if the device is positioned near to it. Most of the popular smartphones were proved to be hazardous for the human body.

Apple then issued a statement, questioning the Tribune's test results for the iPhone 7s “were inaccurate due to the test setup not being in accordance with procedures necessary to properly assess the iPhone models.”

“All iPhone models, including iPhone 7, are fully certified by the FCC and in every other country where iPhone is sold,” the statement said. “After careful review and subsequent validation of all iPhone models tested in the (Tribune) report, we confirmed we are in compliance and meet all applicable … exposure guidelines and limits.”

The Tribune tested 11 cellphone models by measuring how much radiofrequency radiation was absorbed by a simulated body positioned near the phone. The Federal Communications Commission has set an exposure limit of 1.6 watts per kilogram averaged over one gram of tissue.