From what I understand that guy was making his own CS, and making it improperly at that. I also recall that he was making a type that included "silver proteins" or something like that, which is not supposed to be ingested.
Anyway, I don't believe there has ever been a case of a 'blue person' from drinking properly made Colloidal Silver , as the particles are too small to get stuck in the cell. Being though the stuff I use is sold at just about every Vitamin Shoppe across the country, surely a case would've become public by now.