The sodium tetraborate (also known as Borax or Sodium Borate) we use in our Bone Support formula is manufactured to European Pharma grade and is suitable for ingestion and food use. Boric acid and sodium tetraborate may be used as mineral substances in the manufacture of food supplements according to Commission Regulation (EC) No 1170/2009 of 30 November 2009 (copy attached). No limits for the use of boric acid and sodium tetraborate in food supplements have been set in the EU legislation. We can assure you that the use of sodium tetraborate in this supplement is both safe and necessary for the purposes of the supplement.