The jury is still out on exactly how bad nano-tubes are but the good news is that they are generally too small to block your lungs in the same was a soot partic

The jury is still out on exactly how bad nano-tubes are but the good news is that they are generally too small to block your lungs in the same was a soot particles and too soft to cause any mechanical damage. Asbestos fibres are much larger and much stronger - it's like comparing steel drill swarf to chocolate flakes!