Nanocosmetics Used Since Ancient Egypt

Roland Piquepaille writes "French researchers have found that Egyptians, Greek and Romans were using nanotechnology to dye their hair several thousands years ago. Nanowerk Spotlight reports they were using lead compounds which generated lead sulfide (PbS) nanocrystals with a diameter of only 5 nanometers. At a moment where many people wonder if the use of nanoparticles is safe, it's good to know that nanotechnology has been widely used for a very long time."

Comments

We "should" be worried about "nanotech"

[infolib]

At a moment where many people wonder if the use of nanoparticles is safe, it's good to know that nanotechnology has been widely used for a very long time

Ok, all the comments about lead-not-safe and this-isn't-nanotech aside, I think there's something to be said for regulating compounds differently based on particle size.

We do know that some substances changes chemical properties depending on their particle size. We also haven't yet researched the health risks of nanotubes very well, but I think we should do so before spreading tons of the little critters around in field emission displays. They might be quite hard to clean up after the fact.

This is not a call for "safety above all" - it's just an appeal to consider what is already known. (A comparison with cell phones, for instance, would show that cell phone frequencies are by known physics very unlikely to influence chemical reactions beyond thermal effects, hence allowing them per default is quite sensible).

Oh, and why did I write "nanotech" instead of nanotech? Because the term has become a buzzword so broad as to be almost meaningless, not least because thousands of labs have gained access to funding by putting a "Nanotech lab" sign on the door while continuing their usual work. (My place is partly like that). So be careful when using the term "nanotech" - it might mean vastly different things to different people and the ambiguity is being exploited.