Are carbon nanotubes as dangerous as asbestos?
What makes (some) asbestos dangerous is that the fibres can penetrate deep into the lung and once there they stay, cause inflammation and eventual in some cases cancer. They are not easily removed because of their length (>15000 nm) and their insolubility in the lung lining fluid. Some, not all, carbon nanotubes will be similarly insoluble and will be of a length which makes them difficult to remove if they are inhaled into the lung. However it has not yet been demonstrated that these fibres do pose the same risks as asbestos.
