Yes nanotubes by them self present a risk, hence why the lab...

Yes nanotubes by them self present a risk, hence why the lab guys are fully decked out in overalls masks etc... but once the nanotubes have been embedded into the matrix they pose no risk, even in cases of demolition of concrete containing Edencrete.

The YouTube clip clom placed in the forum had the presentor say the follow, and I quote “Once it is suspended in the liquid it is no longer of harm. Then we have done extensive testing for any type of demolition, any types of spills and dries there is absolutely no harm done. Once embedded into the matrix the nano tubes never come liberated again, whether you're grinding, demolishing or anything like that.”