The big three mobile phone makers have been working on technology for over eight years to limit the amount of radiation a user is exposed to.
According to a report in Monday's edition of The Times, Nokia, Motorola and Ericsson have each registered a number of patents for radiation-reducing devices. These components could shield the phone user from radio waves emitted by the handset. One patent from Nokia is reported to include a sentence noting suggestions that continuous exposure to radio frequency radiation could lead to "a development of malignant tumours".
The mobile phone industry has consistently denied claims that mobile handsets can cause cancer, despite some concerns that using the devices can lead to brain tumours. Last year's Stewart Inquiry, set up to examine whether mobile phone use was dangerous, concluded that there was no firm evidence of a health risk but recommended a precautionary approach.
Some industry experts have said in the past that radiation-shielding devices were not feasible because they would stop the phone communicating with the mobile network.
Consumer watchdog Powerwatch claimed that the anti-radiation patents were proof that the handset manufacturers take the risk of health problems more seriously than they have admitted in the past. However, the mobile manufacturers told The Times that there is still no scientific link between phone use and health dangers.
A study being carried out by a team of Swedish researchers has suggested that some benign tumours are more likely to occur on the side of the head against which mobile telephones are usually held. The research looked at mobile phone use of 1,617 patients diagnosed with brain tumours between 1997 and last June. Preliminary results have shown that benign tumours are two and a half times more likely to be found on the side of the head where an analogue phone is typically held.
The Swedish study did not discover any connection between tumour and digital phones -- such as today's GSM handsets. A cancer researcher warned last week that it would take another ten years before the full dangers of GSM phone use are known.
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