[neotokio]

When it comes to titanium it is not that bad. Human body is (most likley) able to deal with titanium (contrary to mercury). However, nanoparticles in itself are problematic because of how they interact with body cells. Good is, possible, better drug delivery (think about possibility of crossing blood-brain barrier), bad is, potential unaccounted effects where body does not recognize nanoparticle as something 'alien', which can create a problems beyond even todays studies.

Case being, why add complexity? There is probably some use for advance technology in certain areas of live, i would gladly take ANY kind of treatment if i would be diagnosed with terminal disease. But why widen your exposure (civilization-wise) for unknowns only at the benefit of pure market profits?

“In more than 50 years of use as a colourant, no verifiable link has ever been shown between general intake of titanium dioxide and ill health in humans,”

That statement in itself is so vague. It's like saying that coal burning has very limited effect on human health because we do it for 150yrs and people are still live. Titanium is not necessary body mineral, therefore counting on 'lucky strike' that it will be assimilated positively is miss-or-hit attitude.

Simplicity over complexity, always.