What does the transition from white chalk on blackboard to black markers on whiteboard mean?

That people will have fewer cases of lung cancer.

Plain chalk is carcinogenic??

I'd assume getting roughly anything in your lungs frequently enough is carcinogenic.

Damn nitrogen.

You have a point. Now that I went looking, most of the literature focus on silicosis, and there aren't many long-term studies that can tell us if it's carcinogenic or not.

It's very likely carcinogenic too, but now I don't know what to expect on the correlation, because it's possible that people die from it before they get the chance of developing a tumor.

But more cases of liver cancer.

What about green chalkboards and multi colored whiteboard markers?

We're deep in contrivance at this point.

Sounds like a new religion in the making!

Socrates: Yes.