Which of the following ions present in low concentration in drinking water is essential for normal growth of teeth but harmful to teeth at high concentration ?
Aluminium
Calcium
Fluoride
Chloride
Answer is Wrong!
Answer is Right!
This question was previously asked in
UPSC CAPF – 2014
– Aluminium: Not considered essential for teeth.
– Calcium: A major structural component of teeth and bones, essential in large amounts. While excess calcium intake can have health implications, its role in teeth is primarily structural, not a trace element with this specific low-dose benefit/high-dose harm profile in drinking water.
– Fluoride: Fluoride ions are absorbed into tooth enamel, making it more resistant to acid attacks and preventing cavities. Low concentrations (typically 0.7-1.2 parts per million or ppm in drinking water) are beneficial for dental health. However, excessive fluoride intake, especially during tooth development, can lead to dental fluorosis (mottling and discoloration of enamel). Very high doses can cause skeletal fluorosis.
– Chloride: An essential electrolyte, but not known for this specific beneficial/harmful effect on teeth development in drinking water.
Therefore, Fluoride is the ion that fits the description.