For what it's worth, I've been taking an 18ppm Colloidal Silver solution every day, at least two(2) ounces, up to three(3) times per day(sometimes more) for a little over two years now. And I haven't seen any signs of blueness yet -knock on wood
That being said, I've been monitoring the whites of my eyes, fingernails and my skin, whenever I go out into the sun. And I'm happy to report, that everything is looking good so far.
Now, I'm certainly not discounting the reality that I may one day develop Argyria, in fact.... I entered into this treatment knowing full well that I could face the reality of one day turning blue. But in my own case, I'd add that I'd rather turn blue than to return to the way things were before I started taking CS.
Anyways... I'll certainly keep everyone posted on my progress as things continue to move on over the years. As the turning point seems to be 6 years in most cases. Though I have some ideas of my own on how to possibly treat Argyria should this condition afflict me. Though I wouldn't dare recommend it to anyone at this stage as it could prove too risky without any formal testing.