Comment by throwup238
4 hours ago
> Considering how much graphite pencils are used across the world, we would've seen hypothetical negative effects already with a high degree of confidence.
Graphitosis is the graphite equivalent of silicosis and asbestosis so yes we’ve got plenty of evidence it’s harmful, but it’s mostly a problem with occupational exposure where large amounts of graphite dust are produced.
That might change if there’s tiny sheets of graphene flaking off everywhere from nanocoatings and it turns out to be carcinogenic for the same reason asbestos is (which isn’t out of the question given the studies on CNTs and nanotoxicity in general).
IIUC graphitosis, silicosis, and black lung require to inhale ungodly amounts of dust. It's orders of magnitude more than we can expect from flaking-based trace contamination.
Why do you expect a different result from "tiny sheets of graphene flaking off everywhere from nanocoatings" compared to the same flaking from graphite smeared across paper?
Pencil graphite breaks off in very large chunks and when you look at them in a microscope the particle size is in the micrometers. Those particles are too big to easily penetrate cells or deep tissue. You understand correctly about the dust issue.
Nanosheets are a different story and I’m worried that the graphene produced for industrial applications will be much smaller, flake off much easier in the field as distinct sheets like from abrasion, and stay airborne for longer. In that form they’re likely to behave like asbestos and the evidence is already pretty strong that they do.