Fluoride to be present in water (mg/L) to prevent caries-
High-Yield Explanation
The recommended fluorine content of water is 0.5 -0.8 mg/L. Fluorine is a double edge sword. Inadequate intake results in dental caries. And excess results in dental and skeletal fluorosis. The use of fluoride is recognized as the most effective way for the prevention of dental caries. Park's Textbook of Preventive and Social Medicine, 25th edition, Page No. 682