From Habr:

Given that the radius of the Earth is more than 6000 km, and humanity has not yet penetrated even further 12 km, your worry is unfounded. It’s like fearing that a colony of intestinal bacteria, covering a thin layer of a stone ball with a diameter of about 12 meters, inside which there is a iron ball with a diameter of about 7 meters, heated to 5000 degrees, will be able to do something wrong with it.