The mobile phone industry has hit back at claims that using hands-free kits with mobile phones increases exposure to radiation by up to three times.
Consumer magazine Which? claimed yesterday that mobile phone users who use hands-free kits - an earpiece attached to the phone by a wire - could be three times more at risk from radiation.
The findings are in contrast to the general opinion that the kits make mobile use safer. Which? is now under pressure from manufacturers to explain how it came to its conclusions.
The magazine tested two hands-free sets from Carphone Warehouse and BT Cellnet. It claimed that both sets acted as aerials, directing three times as much radiation to the head. Although there is no certainty that mobile phone radio waves are harmful, consumers should not rely on a hands-free set, said Which?.
The Federation of the Electronics Industry (FEI) said it is surprised by the findings. The group said tests made by its members and an independent laboratory have shown "without exception that the absorption levels produced when using a headset are significantly less than those produced without a headset".
A spokeswoman for the FEI said: "Until we have more details from Which? regarding the protocol and methodology it used, we can't really compare results."
However, the Which? research did not test specific absorption rate (Sar) - a measurement of the amount of energy absorbed by the human body. The FEI said any conclusions on the effects of radio frequency emissions of mobile phones can only be made on the basis of the Sar levels.
Hands-free kits maker Ora Telecom said it had carried out extensive testing of a wide range of handsets and personal kits from a number of manufacturers and would like further information from Which? on how it carried out its tests.
"It is most unlikely for a piece of wire to amplify the mobile phone radio output by three times," said Ora in a statement. "This would make the earpiece a much more effective aerial than any of the expensive car antennas sold on the market today."
Mobile phone retailer the Carphone Warehouse said today that manufacturers of its hands-free sets have independent research that "wholly contradicts the Which? report findings". The company sought to reassure customers that the balance of research shows that its products meet all safety guidelines.
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