The U.S. Environmental Protection Agency has announced the next step in the agency’s accelerated review of public health risks from fluoride in drinking water: the “Review of Science on Fluoride in Drinking Water: Preliminary Assessment Plan and Literature Survey.”
This fast-track effort marks a step in EPA Administrator Lee Zeldin’s April 2025 directive to expedite EPA’s next fluoride health assessment under the Safe Drinking Water Act schedule, while adhering to what the agency calls "gold-standard scientific methods and radical transparency." This action utilizes data sharing, peer review and interagency collaboration as the agency supports a whole-of-government approach to address public concerns with fluoride, particularly those outcomes related to childhood development and maternal and infant health.
Rather than conducting a fluoride risk evaluation under the Toxic Substances Control Act, the agency determined that a review under the Safe Drinking Water Act, led by the Office of Water, is the most appropriate regulatory pathway for addressing fluoride as a drinking water contaminant. This decision reflects SDWA's specific statutory framework for protecting public health from contaminants in drinking water systems.
The Preliminary Assessment Plan and Literature Survey announced by the agency outlines the transparent and systematic approach EPA intends to follow in evaluating scientific studies of fluoride health effects. The plan describes the key science issues EPA will consider, including sensitive populations such as infants and children, and it compiles a literature survey of relevant health effects studies to be evaluated in the assessment. Releasing this plan for public comment is a step next step in developing a new, comprehensive health assessment on fluoride in drinking water.
According to the EPA, the assessment aims to reflect a comprehensive, current and accurate review of the best available scientific data on fluoride exposure and health effects, conducted with external peer review and public input to inform potential revisions to federal drinking water regulations. EPA says it will use gold-standard scientific practices, draw on expertise across the federal government and will not prejudge any outcomes of the assessment.
The EPA’s role under the Safe Drinking Water Act is to limit the amount of contaminants in drinking water provided by public water systems to protect public health. EPA previously set the maximum contaminant level for fluoride at 4.0 milligrams per liter, a standard designed to prevent known or anticipated adverse health effects that was set in 1986 and most recently reviewed in 2024. Under normal SDWA timelines, the next comprehensive analysis of new scientific information on potential health risks of fluoride in drinking water would not be due until 2030, but the EPA has accelerated this work to deliver updated science to the public sooner while maintaining rigorous review and quality controls.
Decisions on whether to add fluoride to drinking water are guided by public health recommendations from the Department of Health and Human Services and the Centers for Disease Control and Prevention and have ultimately been made at the state or local level. U.S. Public Health Service has issued Recommendations for Fluoride Concentration in Drinking Water for the Prevention of Dental Caries, otherwise known as tooth decay. CDC’s Community Water Fluoridation Program recommends amounts of fluoride in drinking water to best prevent cavities. Their recommended optimal level of fluoride is 0.7 milligrams per liter. These recommendations are just that — recommendations that are advisory and do not alter EPA’s legal role under the SDWA.
The federal regulatory standards set by EPA apply regardless of whether fluoride is naturally occurring in a system’s source water or is intentionally added by the water system. EPA’s responsibility is to ensure that overall fluoride levels remain within health-protective limits, but the agency does not make policy recommendations to state or local systems to add fluoride to drinking water.
EPA’s new plan will be available for public comment for 30 days once it is published in the Federal Register.