So how is the toilet so clean?
It’s pretty simple really…we actually clean the toilet. Because we generally think of the toilet as being dirty we clean it with all sorts of chemicals. Toothbrushes, kitchen sponges, and cell phones on the other hand are cleaned rarely, if at all.
Besides, if everything was laboratoy-clean, we would be sick 24/7. We are supposed to be in touch with bacteria, so our system learns how to reject them.