FLUORIDE has several mechanisms of toxicity. Ingested fluoride initially acts locally on the intestinal mucosa. It can form hydrofluoric acid in the stomach,
which leads to GI irritation or corrosive effects. Following ingestion, the GI tract is the earliest and most commonly affected organ system. Once absorbed, fluoride binds calcium ions and may lead to
hypocalcemia:
[1] Fluoride has direct cytotoxic effects and interferes with a number of enzyme systems; it disrupts oxidative phosphorylation, glycolysis, coagulation, and neurotransmission
(by binding calcium);
[2] Fluoride inhibits Na+/K+ -ATPase, which may lead to hyperkalemia by extracellular release of potassium;
[3] Fluoride inhibits acetylcholinesterase, which may be partly responsible for hypersalivation, vomiting, and diarrhea (cholinergic signs). Seizures may result from both
hypomagnesemia and hypocalcemia.
[4]Severe fluoride toxicity will result in multiorgan failure. Central vasomotor depression as well as direct cardiotoxicity also may occur. Death usually results from respiratory paralysis,
dysrhythmia, or cardiac failure.
