EPA advances expedited fluoride health assessment under Safe Drinking Water Act
The U.S. Environmental Protection Agency (EPA) has released a new scientific protocol outlining how it will evaluate potential health risks associated with fluoride in drinking water, marking the next step in an accelerated review that could inform future federal drinking water regulations.
The Protocol for Developing the Fluoride Human Health Toxicity Assessment describes the agency's methodology for conducting a dose-response analysis to determine fluoride exposure levels that may pose health risks. EPA said the protocol incorporates public comments received on its earlier Preliminary Assessment Plan and Literature Survey.
According to the agency, the assessment will focus on two primary health endpoints in children: neurodevelopmental effects, including potential impacts on brain function and IQ, and dental fluorosis, which can cause discoloration and pitting of tooth enamel.
EPA Administrator Lee Zeldin said the agency is expediting the assessment under the Safe Drinking Water Act (SDWA) in coordination with the U.S. Department of Health and Human Services (HHS), with the goal of completing the review years ahead of the standard timeline.
The agency said it will use systematic review methods and consult with HHS experts while developing a draft human health toxicity assessment. Once completed, the draft assessment will be released for public comment before being finalized.
The final assessment could serve as the scientific basis for potential revisions to EPA's federal fluoride drinking water regulations and provide information for states and local governments that make decisions about community water fluoridation.
EPA currently regulates fluoride under the SDWA with a maximum contaminant level (MCL) of 4.0 milligrams per liter, a standard established in 1986 and most recently reviewed in 2024. Separately, the U.S. Public Health Service and the Centers for Disease Control and Prevention recommend an optimal fluoride concentration of 0.7 milligrams per liter to help prevent tooth decay, although those recommendations are advisory and distinct from EPA's regulatory authority.
The agency emphasized that its drinking water standards apply to both naturally occurring fluoride and fluoride intentionally added by public water systems, while decisions about whether to fluoridate drinking water remain the responsibility of state and local governments.