Texas Commission on Environmental Quality (TCEQ). Class C Water License Exam

Fluorides in drinking water should not exceed what concentration?

1. 1.0 mg/L

2. 2.0 mg/L

3. 4.0 mg/L

4. 5.0 mg/L

The correct answer is: 4.0 mg/L

The correct concentration limit for fluorides in drinking water is recognized as 4.0 mg/L. This guideline is established based on health considerations to minimize the risk of dental fluorosis, which can occur when excessive fluoride is ingested during the formative years of tooth development. Additionally, the concentration is determined by balancing the benefits of fluoride in preventing dental cavities with the potential adverse health effects associated with higher levels of fluoride exposure. In many regulatory frameworks, including those provided by health organizations and water quality standards, the 4.0 mg/L limit is deemed appropriate for maintaining safe drinking water while still allowing for the protective effects of fluoride. Lower concentrations, such as 1.0 mg/L and 2.0 mg/L, would not provide sufficient dental benefits, while a concentration of 5.0 mg/L exceeds the safety threshold, increasing the risks of negative health impacts. Thus, the 4.0 mg/L standard represents an optimal compromise between safety and health benefits in drinking water supplies.