I hate to say this, but that sort of thing is usually caused by some sort of dressing or cleaning solution. I have seen ArmorAll "protectant" cause this sort of thing.
My first attempt would be to use glass cleaner to try and remove the residue. This is not always successful and sadly, the only remedy would be to replace the lenses. You could also try polishing them with a light finishing polish, but do so at your own risk.