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Information Regarding Fluoride

What happened?

On Jan. 7, 2011, the U.S. Department of Health & Human Services (HHS) and the Environmental Protection Agency (EPA) announced important steps being taken to ensure that standards and guidelines on fluoride in drinking water continue to protect consumers while promoting good dental health, especially in children. Briefly, the two agencies are proposing the following:

  • HHS is proposing that community water systems that fluoridate should adjust the amount of fluoride to 0.7 mg/L to achieve an optimal fluoride level and prevent tooth decay. This is a change to the Agency's previous recommendation which suggested an optimal range of 0.7 - 1.2 mg/L based on ambient air temperature and the effects of air temperature on water consumption. HHS will be publishing their proposal in the Federal Register with a 30-day public comment period.
  • EPA is initiating a review of the maximum amount of fluoride allowed in drinking water. The current federal primary MCL for fluoride is 4.0 mg/L. EPA's announcement is a strong indication that the MCL may be revised, but a decision has not yet been made to do so. If a decision is made to revise the standard, the Agency will need to go through all of the applicable rule-making steps. Note: Pennsylvania's current drinking water standard is more protective with a primary MCL for fluoride of 2.0 mg/L.

Why did the Agencies decide to take these actions?

Data indicates that fluoride exposure levels among the population have increased in the last 40 to 50 years, resulting in an increase in some effects on teeth (i.e., mild dental fluorosis is associated with lacy white markings or spots on the enamel). Water is now one of several sources of fluoride. Other common sources include dental products (such as toothpaste and mouth rinses, prescription fluoride supplements, and fluoride applied by dental professionals) and dietary sources (such as food and beverages made with fluoridated water).

In 2003, EPA requested that the National Academies of Science (NAS) conduct a review of this data. In 2006, the NAS issued a report recommending that EPA update its health and exposure assessments to take into account bone and dental effects and to consider all sources of fluoride. In December 2010, EPA completed an updated peer-reviewed assessment of fluoride for protection against severe dental fluorosis. EPA determined an oral Reference Dose (RFD) for fluoride of 0.08 mg/kg/day. The dietary portion is estimated to be 0.01 mg/kg/day and the drinking water contribution is estimated at 0.07 mg/kg/day. The drinking water contribution of 0.07 mg/kg/day would equate to a concentration of approximately 2.4 mg/L for a 70 kg adult drinking two liters of water per day. EPA concluded that the RFD is also protective against fractures and skeletal effects in adults.

What does this mean for public water systems that are adding fluoride to their water?

No action is required at this time. The current MCL of 2.0 mg/L is still in effect and permits issued for water fluoridation are protective of this standard. The CDC's new dosage recommendation is proposed. When the recommendation is final, it will still only represent a recommendation. The only requirement is the drinking water standard of 2.0 mg/L.

In Pennsylvania, water systems that fluoridate do so under a permit by the department. Water suppliers that are interested in lowering their fluoride concentration as a result of the CDC's proposed recommendation should review their permit. If the permit includes a special condition that specifies an optimal fluoride concentration or range, the water supplier will need to request a minor amendment prior to lowering the fluoridation level. Water suppliers without this special condition may make the necessary changes to lower their fluoride concentration. Please note if equipment or chemical changes are anticipated as a result of this change, a permit amendment may be necessary. Please contact your regional permitting staff for more information.

The complete removal of water fluoridation is considered a substantial modification and would require a major permit amendment prior to cessation of water fluoridation. Water systems that are contemplating the removal of water fluoridation are reminded of the following:

  • Water suppliers shall provide advance notice to consumers and medical professionals of the decision to cease operation of fluoridation treatment. Evidence of this notice must be included in the permit application.
  • Any operation permit approving the cessation of fluoridation will include a special condition to require public notification before addition is stopped.
  • A supplier that removes fluoridation should also take the opportunity in the next annual Consumer Confidence Report (CCR) to remind customers of the date that fluoridation was discontinued.

For more information, please refer to the department's guidance entitled:
Proposals to Add or Remove Fluoridation Treatment by a Community Water System” (DEP 383-2125-001) (PDF).

What does this mean to consumers?

The current MCL of 2.0 mg/L is still in effect and permits issued for water fluoridation are protective of this standard. Consumers should refer to their water system's CCR or call their water system for information about water fluoridation levels.

More information is available at the following links:

If consumers have specific health concerns, they should consult their health care providers.