Not really; or rather, I should say, the issue isn't nearly as clear-cut as some of the anti-nanotech groups that have been screaming about it would have you be

Not really; or rather, I should say, the issue isn't nearly as clear-cut as some of the anti-nanotech groups that have been screaming about it would have you believe. They usually point to research by Ken Donaldson, showing similar pathogenic effects between asbestos and nanotubes longer than 20 μm, but fail to acknowledge that there's a difference between nanotubes (and graphene) in general and long nanotubes in particular, as Donaldson's study clearly points out. In brief: > The basis of toxicity of asbestos and other fibrous materials is now reasonably well understood; their toxicity is based on the physical nature of the materials, rather than their chemical composition. In particular, fibres are expected to be toxic if they are long – longer than about 20 µm – and rigid. The mechanism of this pathogenicity is believed to be related to frustrated phagocytosis. Phagocytes are the cells whose job it is to engulf and destroy intruders – when they detect a foreign body like a fibre, they attempt to engulf it, but are unable to complete this process if the fibre is too long and rigid. Instead they release a burst of toxic products, which have no effect on the fibre but instead cause damage to the surrounding tissues. There is every reason to expect this mechanism to be active for nanotubes which are sufficiently long and rigid. [1] Donaldson's research doesn't somehow negate the benefits--or even the possibility--of nanotubes; on the contrary, he's rather upbeat: > There is a silver lining to this research. According to Donaldson, "Short or curly carbon nanotubes did not behave like asbestos, and by knowing the possible dangers of long, thin carbon nanotubes, we can work to control them. It's a good news story, not a bad one. It shows that carbon nanotubes and their products could be made to be safe." [2] [1] http://www.softmachines.org/wordpress/?p=409 http://www.softmachines.org/wordpress/?p=409 [2] http://www.sciencedaily.com/releases/2008/05/080520144004.htm http://www.sciencedaily.com/releases/2008/05/080520144004.ht... [3] http://spectrum.ieee.org/nanoclast/semiconductors/nanotechnology/when-you-keep-nanotubes-short-theyre-not-like-asbestos http://spectrum.ieee.org/nanoclast/semiconductors/nanotechno... [4] http://spectrum.ieee.org/tech-talk/semiconductors/devices/the_long_and_short_of_carbon_n http://spectrum.ieee.org/tech-talk/semiconductors/devices/th...