I don’t believe Suffield has a BL4.
I’m slightly skeptical on the isotope ratios.
Maybe they show something, maybe not.
Same for the silicon coating.
Too many contradictory reports and possible disinformation on this.
The purity and aerosolization of the Daschle anthrax seems to be the one thing that is not in doubt.
I would think the silicone could be obtained as a residual surfactant in a sprayed and dried mixture.