A new study suggests that for thousands of years, humans have been exposed to nanoparticles shed by metal items such as silver cutlery (Photo: Rudolph de Salis)
Nanoparticles have been a key part of numerous recent technological advances. Biofuels, solar cells, medical imaging systems and even sunscreen - there's virtually no field of science or technology that they couldn't potentially transform. There are concerns however, about the risks posed by the countless tiny particles of materials such as silver, gold and titanium dioxide that are now entering our environment and our bodies, but a recent University of Oregon study suggests that if not completely harmless, nanoparticles are at least nothing new. In fact, it states, humans have been exposed to them for millennia.