Fluorine is a halogen with the chemical symbol F, and the atomic number 9. Fluoride compounds are used in making steel, chemicals, ceramics, lubricants, dyes, plastics, and pesticides. Fluorides are often added to drinking water supplies and to a variety of dental products, including toothpaste and mouth rinses, to prevent dental cavities. (2)
belongs to the class of inorganic compounds known as homogeneous halogens. These are inorganic non-metallic compounds in which the largest atom is a nobel gas.
Fluoride ions are incorporated into bone by substituting for hydroxyl groups in the carbonate-apatite structure to produce hydroxyfluorapatite, thus altering the mineral structure of the bone. Alteration in mineralization increases hardness and bone mass, but also decreases mechanical strength. A portion of the circulating inorganic fluoride acts as an enzyme inhibitor because it forms metalfluoride-phosphate complexes that interfere with the activity of those enzymes requiring a metal ion cofactor. In addition, fluoride may interact directly with the enzyme or the substrate. It is a general inhibitor of the energy production system of the cell. Fluorine may bind calcium and decrease its concentration. This is thought to indirectly inhibit amelogeninase activity, resulting in altered crystal growth and subsequently causing dental fluorosis. (2)
Metabolism
Fluorides may be absorbed following inhalation, oral, or dermal exposure. Once in the body, the fluoride ion is transported in the blood and accumulates in the bones and teeth. Fluoride is believed to replace the hydroxyl ion (OH-) and possibly the bicarbonate ion (HCO3-) associated with hydroxyapatite—a mineral phase during formation of bone. The resultant material is hydroxyfluorapatite. Once absorbed, a portion of the fluoride is deposited in the skeleton, and most of the remainder is excreted in the urine, with smaller amounts in feces, and sweat, and saliva. (2)
3, not classifiable as to its carcinogenicity to humans. (1)
Uses/Sources
Fluoride compounds are used in making steel, chemicals, ceramics, lubricants, dyes, plastics, and pesticides. Fluorides are often added to drinking water supplies and to a variety of dental products, including toothpaste and mouth rinses, to prevent dental cavities. (2)
Minimum Risk Level
Not Available
Health Effects
Exposure to high levels of fluoride can result in denser bones. However, if exposure is high enough, these bones may be more fragile and brittle and there may be a greater risk of breaking the bone. Chronic exposure may also cause dental fluorosis, which alters the appearance of children's teeth during tooth development. (2, 3)
Symptoms
Symptoms of fluoride exposure include abdominal pain, diarrhea, dysphagia, hypersalivation, mucosal injury, nausea, vomiting. Electrolyte abnormalities including hyperkalemia, hypocalcemia, hypoglycemia, and hypomagnesemia may occur. Neurological symptoms include headache, muscle weakness, hyperactive reflexes, muscular spasms, paresthesia seizures, tetanic contractions, and tremors. In severe cases, multiorgan failure will occur. Death typically results from cardiac arrest, shock, widening of QRS, and various arrhythmias occur. (3)
Treatment
Oral exposure to fluoride compounds should be treated by giving milk, calcium carbonate, or milk of magnesia to slow absorption. Eye or skin contact should be treated by removing any contaminated clothing and flushing with water. (3)
