This is something I have wondered about for quite some time. Apple's touch displays are coated with a polymer that contains nano-particles which are meant to prevent skin oils from sticking to the glass thus making them "finger print resistant". They call it an "oleophobic" coating. As many owners of these devices will be aware, the coating wears away after many months of use from constant touching, tapping and swiping. What I want to know is, when this film wears away where are these nano particles going? With the pressure of fingers being rubbed against these surfaces I would imagine that it goes directly into the skin. If so, I would then imagine that this would be a potential health hazard for the end users as well. I have yet to see any scientific analysis of this but perhaps I am talking crazy. Either way, I would like to hear some opinions from folks with more knowledge in this area.