Rubbing alcohol is safe for marble and skin when it comes to cleaning marble, but it has limited ability to germ killing. The chemical composition of alcohol does not damage the surface of marble unlike other cleaners such as bleach or vinegar. Vinegar can be used across the household as a disinfectant, but to address the question of how to clean marble, this is not the right choice. A mild use of alcohol can disinfect the surface while also protecting the look of a marble countertop or surface.