Mobile phones emit microwave radio emissions. Researchers are questioning whether exposure to these radio waves might (1) ________ to brain cancer. So far, the data are not conclusive. The scientific evidence does not (2) _______ us to say with certainly that mobile phones are categorically (3) _________. On the other hand, current research has not yet (4) _________ clear adverse effect associated with the prolonged use of mobile phones. Numerous studies are now going (5) _________ in various countries. Some of the results are contradictory but others have shown an association between mobile phone use and cancer. (6) _________ these studies are preliminary and the issue needs further, long-term investigation. (7) _________ the scientific data is more definite, it is prudent for people to try not to use mobile phone for long (8) _______ of time. Do not think that hands free phones are any safer either. At the moment, research is in fact showing the (9) _______ and they may be just as dangerous. It is also thought that young people (10) ________ bodies are still growing may be at particular risk.