Fluoride

Introduction: Fluoride is the ionic form of fluorine, a naturally occurring chemical element. Small amounts can help prevent dental caries, but prolonged exposure to excessive fluoride, particularly through drinking water, can cause fluorosis.

Key pointers

  • Chemical symbol of fluorine: F.

  • Fluoride ion: F⁻.

  • Natural sources: Fluoride-bearing rocks, minerals and groundwater.

  • Dental benefit: Appropriate fluoride exposure strengthens tooth enamel and reduces the risk of dental caries.

  • Dental fluorosis: Excessive fluoride exposure during tooth development can cause changes in enamel, including white streaks or brown staining in more severe cases.

  • Skeletal fluorosis: Long-term excessive exposure can cause bone and joint changes and, in advanced cases, substantial skeletal disability.

  • Drinking-water guideline: The World Health Organization's guideline value for fluoride is 1.5 mg/L.

  • Indian context: Fluoride contamination is an important groundwater-quality issue in several parts of India.

  • Control measures: Safe alternative water sources, defluoridation where appropriate, and monitoring of drinking-water quality.

UPSC focus: Fluorosis is associated with excessive fluoride intake, not fluoride deficiency. Remember that naturally occurring groundwater contamination is a major public-health concern.