Researchers at the Project on Emerging Nanotechnologies in Washington say tiny particles used in cosmetics and sunscreens may pose health concerns.
Speaking at the Science Media Center in London, Andrew Maynard, of the Project on Emerging Nanotechnologies, said: "In a sense we are using humans as guinea pigs with a lot of these products. There are few proven risks but there are proven hazards."
Such particles exist in the air, produced by volcanoes and the burning of fossil fuels, but scientists can now engineer materials at tiny sizes to give them useful properties, the Telegraph reported.
Researchers set up an Internet directory listing more than 200 products that claim to use nanotechnology. Face creams using nanoparticles include L'Oreal's Revita-Lift treatment mask and Lancome Renergie Morpholift. Some Soltan sun creams, produced by Boots and Oxonica, also make use of nanotechnology.
A Royal Society and Royal Academy of Engineering study concluded that most nanotechnologies posed no risks but highlighted potential hazards and called for tighter controls.
Copyright 2006 by United Press International
Explore further: Self-replicating nanostructures made from DNA