Hello. I've been around chickens since I was a young boy (now in 70s). I know how to recognize eggs that are going bad. I recently put 8 hens in a small back yard that has no grass. Of course they enjoy wallowing and dusting since the yard will not grow grass. I have noticed what appears to be dirt in the egg whites. Is this really dirt that somehow is traveling from the ground up into the albumin via the oviduct? Thanks.