The Director General of the World Health Organisation, Ms Gro Harlem Brundtland, has warned parents against letting their children spend too much time on mobile telephones and said their electromagnetic waves give her a headache.
Brundtland does not own a mobile phone and forbids anyone to use one in her Geneva office, saying this is to protect herself from the electromagnetic waves.
"If you enter my office, you are invited by me. No one who is invited would like to give me headaches," Brundtland said at a news conference in Oslo on Monday, where she attended an international conference on cancer.
Some tests have shown higher electromagnetic waves in places where mobiles are frequently used, but research has still to prove any long-term negative effects of mobile phone usage.
"I would be cautious about letting children use mobile phones for hours every day, because we don't know enough about the damage," Brundtland said. "The same goes for microwaves."