Fluorine occurs naturally in the body as calcium fluoride and is found primarily in the bones and teeth. Fluorine serve as a catalyst for both the mineralization of developing tooth enamel prior to tooth eruption and for remineralization of surface enamel. Natural water contains 3-12 mg of Fluoride per litre and sea fish 5-10ppm
Ingested fluorides are completely ionized and rapidly absorbed, and distributed throughout the extra cellular fluid. Fluride is rapidly excreted in the urine. Level of fluoride in blood and tissues is very low.