IS NANO-PHOBIA infectious? It certainly seems to be spreading. In Britain, Prince Charles gave it a helping hand by speaking out about his fears over nanotechnology earlier this year. Last month, green campaigners and others met in Brussels for the world's first summit on the dangers of nanotechnology. The British government is so worried about nano-phobia it has asked the Royal Society to look into the issue. How seriously should we be taking it?

The laboratory techniques that gave birth to the nanotechnology revolution were hardly terrifying. Twenty years ago, at an IBM laboratory in Zurich, two scientists built the first scanning tunnelling microscope (STM), which made it possible to "see" individual atoms by scanning a tiny probe over the surface of a silicon crystal. It was hard to believe that such a simple concept could produce an image in atomic detail. Labs all over the world were soon building ...