A major study preformed on 420,000 Danish people proved that cell phones beam radiofrequency energy that can break through the brain’s outer edge, which has raised questions about cancers of the head and neck, brain tumours or leukaemia are not associated with increased cancer risk. Most research has found no risk, but a few studies have raised questions. People can be reassured that these devices are safe as more and more evidences are proving the fact. However the final word is not there yet.

U.S. health officials insist the evidence shows no real reason for concern, they don’t give the phones a definitive clean bill of health, either, pending long-term data on slow-growing cancers.
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