[blix]

What about larger sizes :) Physical effects can matter as much as chemical. Diatomacious earth has conflicting evidence anyway. Silica gel and glass aren't really the same thing.

I did mean TiO2. There is a reason the EU considers it a carcinogen and is banning it from several classes of products.

[kragen]

Silica gel is glass with nanometer-sized pores in it. Bottle glass has additional additives that lower its melting point and increase its solubility (oxides of sodium and calcium).

The EU has irrationally banned all sorts of things since the witch-burners have seized control of the government apparatus. Borate fire retardants and fertilizers is one of my favorite examples.

[blix]

Make some car windows out of silica gel and let me know how it goes :) I think you will find nanometer-sized pores can actually matter a lot!

I'm not sure dismissing all research that disagrees with me as witch-burning would be a good habit as a scientist.

[kragen]

Nanometer-sized pores matter enormously, which is why we make silica gel in the first place, but not in ways that make other forms of amorphous silica more toxic than silica gel.

I'm not dismissing research that disagrees with me as witch-burning. I'm dismissing people who disagree with literally all the research.