Public Health · single question
What is the recommended level of fluoride in community water supplies?
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Correct answer: C. 0.7 ppm
- A. 1.0 ppm was the older recommendation — the current standard (since 2015) is 0.7 ppm.
- B. 1.5 ppm exceeds the current recommendation and may increase the risk of dental fluorosis.
- C. The HHS/CDC revised their community water fluoridation recommendation in 2015 to 0.7 mg/L (0.7 ppm) — down from the previous range of 0.7-1.2 ppm. This single recommended level accounts for increased fluoride exposure from other sources (toothpaste, fluoride treatments). At 0.7 ppm, communities receive caries-preventive benefit while minimizing risk of dental fluorosis.
- D. 0.5 ppm is below the recommended therapeutic level for community water fluoridation.