Here are a couple sites that tell about the many uses of borax and its safety.
If you have a problem with ants, here is a formula to deal with it:
1/2 C sugar
1 1/2 Tablespoons of Borax
1 1/2 cups warm water
Mix it up, soak cotton balls, and lay the balls out on jar lids or plastic container covers around the area where ants are.
More details at How to Kill Ants Using Borax