What is the MCL for fluoride?

The Maximum Contaminant Level (MCL) for fluoride is established to protect public health by limiting the levels of fluoride in drinking water. The correct threshold for fluoride is set at 4.0 mg/L. This level is based on evaluations of potential health risks associated with excessive fluoride intake, which can lead to dental and skeletal fluorosis. Setting the MCL at this level aims to balance the dental health benefits of fluoride, such as its role in preventing tooth decay, with the risks of adverse health effects when fluoride concentrations are too high.

Fluoride levels above 4.0 mg/L are considered a risk to health, leading to regulations that mandate monitoring and control of fluoride levels in public drinking water supplies. The decision to set the MCL at this concentration reflects extensive research and is aligned with guidelines from various health organizations, which aim to ensure safe drinking water for the population.