Fluoride and Boron

This is kinda off topic, but for those interested in Fluorine Detox there was a solid test run by Fluorine Chemists in the 80's using Borax. They measure the fluoride in the urine of some 30 participants after giving huge doses of Borax.
They say that it is safe, but I have never taken more than a pinch myself.

http://www.naturallifeenergy.com/files/borox-effect-skeletal-fluorosis.pdf

It seems that Fluoride has a higher affinity for Boron than for bones.