Final answer:
Fluorosis can result from the excessive consumption of fluoride leading to the formation of fluorapatite in teeth and bones, displacement of hydroxyl groups in bones, and altering bone density.
Step-by-step explanation:
The three possible mechanisms resulting in fluorosis are associated with the intake of fluoride. Excessive ingestion of fluoride can lead to:
- Formation of fluorapatite by the reaction of fluoride ions with hydroxyl apatite in teeth, which in excessive amounts leads to dental fluorosis, causing discoloration and pitting of tooth enamel.
- Displacement of hydroxyl groups in bone's hydroxyapatite crystals to form fluorapatite, which can stabilize and strengthen the bones but also lead to skeletal fluorosis if the fluoride intake is too high, resulting in stiffened joints and thickened bones.
- Interaction with bone mineral density by fluoride entering spaces within hydroxyapatite crystals, increasing the density excessively and altering bone structure.
This condition is often observed in areas with naturally high levels of fluoride in groundwater. While fluoride is beneficial to dental health in small quantities, preventing tooth decay, its excessive presence can cause fluorosis. Consequently, although community water fluoridation is a common practice for dental health, the US Environmental Protection Agency sets maximum fluoride levels to prevent these negative impacts.