I wouldn't be too worried about a couple of little plastic pieces. Chances are if they made it too far they would just burn up. I once dropped a whole qtip into my cylinder (while trying to clean the threads) and the car just ate it up! It missed for about 25 seconds while it destroyed it, and then all was well. Maybe I had a small pile of goo on the top of the piston, but I am sure that went away after a while. A turbo is prety hot so it would probably at least soften it enough to help it not cause any more damage. Metal chunks I would be more worried about, but something that can burn easily, I think you would be fine.
Just my two cents though, if you are paranoid enough (which I am guilty of with lots of things, it not bad) then go ahead and have a look. But you have to ask your self how long ago did these things pull up anchor? You might be hunting down a couple of plastic bits that sorted themselves out months ago!
Tboy