As with any ice play, one should be careful that the ice is not too cold. Remember that ice just removed from a freezer will typically be between -15C to -20C. Temperatures that cold can freeze moist skin in just a few seconds. I have a freezer that is particularly cold (-30C), and the ice coming out of it can cause minor frostbite on exterior skin ... not to mention what it would do vaginally or anally. It is always good practice to run ice cubes or ice dildos under cold water to raise them from their just-out-of-the-freezer temperature up to just-below-0C. Play safe! Rectum frostbite ... that'd be both painful and embarrassing to explain!