What is the optimum range in mg/l for fluoride in treated water?

The optimum range for fluoride in treated water, particularly in the context of public health and dental health benefits, is set to promote dental health while minimizing the risk of dental fluorosis. This optimum level is generally considered to be around 0.7 mg/l.

This concentration was determined based on research showing that fluoride can significantly reduce the incidence of cavities in children and adults without causing adverse effects. Values above this level may not provide additional benefits and could increase the risk of fluorosis, which can lead to discoloration and damage to enamel in teeth.

While lower and higher fluoride levels are included in other choices, they do not represent the optimal balance for health benefits versus potential risks. Therefore, 0.7 mg/l is recognized as the ideal concentration for fluoride in treated water to achieve protective effects for dental health while ensuring safety.