However, nanotechnology might present other risks. Some scientists are concerned that new types of nanoparticles could be bad for the environment and human health.
But nanoparticles already exist in nature: in volcanic ash, ocean spray, forest-fire smoke, clouds and clay. We also create them when we smoke a cigarette or fry our food or drive our cars.
In a busy city like London, we may well be breathing in a million nanoparticles with each breath. So what is all the fuss about?
|Volcanoes are one of the sources of naturally occurring nanoparticles.|