Both natural and anthropogenic metal contamination of soil and natural waters result in environmental problems and serious health risks globally. Some metals such as arsenic or tungsten often form negatively charged ions that hydroxyapatite, or fish bone, does not immobilize efficiently. The effectiveness of surface-functionalization, or modification, using iron-amendments on a super cleaned (boiled, bubbled (density separation), bleached (H2O2), and baked) commercial biogenic fishbone product (Apatite IIÌ¢"_å¢) and raw catfish head were examined. Bench-scale experiments demonstrated the ability of surface-functionalization using ferrous and ferric iron chloride amendments to modify Apatite IIÌ¢"_å¢ and catfish bone, which resulted in significant improvement in arsenate and arsenite removal efficiency in a simulated groundwater. Significant improvement in tungstate removal efficiency was limited to surface-functionalization by the ferric chloride amendment.