Any feces on the exterior of an egg shell poses a food safety threat from potential cross-contamination if, say, a consumer cracks open an egg then proceeds to prepare a salad with those same bacteria-riddled hands.

FORBES: Why American Eggs Would Be Illegal In A British Supermarket, And Vice Versa

In order to clone a human, scientists would remove the nucleus of an egg and extract its genetic material, leaving just its shell.

CNN: Group says it will move human cloning work offshore