Water - As introduced, decreases from 1.5 milligrams per liter to 0.4 milligrams per liter the threshold for the presence of fluoride in a public water system that requires an increase in the frequency of fluoride-level testing from quarterly to monthly; requires public water systems to cease adding fluoride to drinking water supplies by May 1, 2025, and provide written notice of cessation of fluoridation to customers. - Amends TCA Title 68, Chapter 221, Part 7.

This bill would require Tennessee public water systems to test fluoride levels monthly if they exceed 0.4 milligrams per liter (down from 1.5 mg/L), instead of quarterly. It mandates that all systems stop adding fluoride to drinking water by May 1, 2025, and provide customers with 30 days' written notice before discontinuing fluoridation. Systems must resume quarterly testing once three consecutive monthly results fall below 0.4 mg/L. The bill exempts naturally occurring fluoride that doesn't exceed federal limits.