Which of the following statements about fluoride levels in community water supply is true?

The statement is accurate because the optimal fluoride level in community water supplies is important for public health, specifically in the prevention of dental caries. The U.S. Public Health Service recommends a fluoride concentration of about 0.7 parts per million (ppm) in drinking water to provide maximum dental benefits while minimizing the risk of dental fluorosis. Enriching fluoride levels above this optimal level is unnecessary and can potentially lead to adverse effects, such as increased occurrences of dental fluorosis.

Understanding the context of water fluoridation is essential. Fluoride naturally occurs in varying concentrations in water supplies, and proper management ensures that communities benefit from adequate decay prevention without exceeding recommended guidelines. Excessive levels could be harmful, and under-fluoridated water might not provide the necessary protective effects against tooth decay. Therefore, the focus should always be on maintaining fluoride levels within the beneficial range rather than exceeding it unnecessarily.