A study conducted by the Radiation and Nuclear Safety Authority in Finland has concluded that people who have used a mobile phone for 10 years have an increased risk of developing brain tumors on the side of the head where they held the handset.

Prof Lawrie Challis from the Mobile Telecommunications Health Research program said that short term use of mobile phones was safe but that this study raised the need for more research on the long term effects.

The Mobile Operators Association denied that the study shows any increased risk associated with mobile phone usage, saying that "the findings related to tumor location are difficult to interpret."

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