Updated consumer risk assessment of fluoride in food and drinking water including the contribution from other sources of oral exposure

Disclaimer

• This plain language summary (PLS) is a simplified communication of EFSA’s Updated consumer risk assessment of fluoride in food and drinking water including the contribution from other sources of oral exposure. The full EFSA opinion can be found here.
• The purpose of the PLS is to enhance transparency and inform interested parties on EFSA’s work on the topic using simplified language to present a summary of the main findings.

Background to the scientific opinion

• Fluoride is a naturally occurring element that can inhibit tooth decay.
• The primary sources of human exposure are drinking water (naturally occurring or fluoridated), food, fluoridated salt and toothpaste. In the European Union (EU), fluoridating public drinking water is done only in very few Member States but approximately 90 % of toothpastes sold contain fluoride.
• In 2013, EFSA assessed the benefits of fluoride and determined an adequate intake (AI) needed for its protective effects against tooth decay. In 2005, EFSA determined tolerable upper intake levels (ULs) for various age groups to prevent adverse effects, such as dental and skeletal fluorosis in children and adults.
• This updated risk assessment examines potential health risks from fluoride, focusing on its neurotoxicity and developmental neurotoxicity (DNT). It also examines health risks on the thyroid and bone.

What was EFSA asked to do?

• The European Commission (EC) asked EFSA to update the consumer risk assessment for fluoride from food and drinking water.
• The mandate was prompted by recent studies that suggested a possible link between fluoride intake and DNT in children, potentially at drinking water concentration levels below 1.5 mg/L, the EU legal maximum.
• EFSA was asked to review all relevant hazard information and all potential sources of fluoride intake to ensure that the current safety standards are adequate.

How did EFSA carry out this work (and what data were used)?

• To assess potential health risks, EFSA systematically reviewed scientific studies on fluoride's effects, prioritising its impact on the central nervous system (CNS) including DNT, as well as on the thyroid and bone.
• To determine how much fluoride people consume in total, the assessment combined all main sources of intake, such as food, drinking water, fluoridated salt and dental care products.
• The review was based primarily on the scientific literature published between 2005 and 2024, along with recent data on fluoride levels in food and water from EFSA and EU national authorities. Relevant publications before 2005 and since 2024 were also considered.

What were the outcomes?

• EFSA’s experts determined a safe daily fluoride intake, protective against neurodevelopmental risks, of 3.3 mg for pregnant women (protection from DNT in the developing fetus), which also applies to other adults and children over eight years old. This safe intake level also protects against risks for adverse effects on thyroid and bone.
• Fluoride ULs were determined for children, to prevent dental fluorosis and other adverse effects, at:
  o    1 mg per day for infants (<1 year),
  o    1.6 mg per day for toddlers (1-3 years),
  o    2 mg per day for children aged 4-8 years.
• It was found that if fluoride concentrations in drinking water were at the EU legal limit of 1.5mg/L, this would lead to a total fluoride exposure above the newly determined ULs and safe level of intake.
• Actual drinking water concentration data submitted to EFSA indicated that more than 86 % of samples contained less than 0.3 mg/L fluoride, and more than 97 % of samples contained less than 0.7 mg/L fluoride.
• Based on these data, EFSA estimated that for typical fluoride concentrations in drinking water in Europe total fluoride exposure does not exceed the safe level of intake or the ULs determined for the different age groups (except in 4-8-year-old children) and therefore does not pose a health concern.
• Under the same scenario, and the most conservative assumption of 100% ingestion of dental care products, mild fluorosis may occur in children aged 4-8 years, affecting their molar teeth, which develop during this period.

What were the limitations/uncertainties?

When establishing ULs and safe fluoride intake levels, EFSA considered several significant uncertainties. These uncertainties fall into two main areas:

• Hazard assessment:
  o    Inconsistent evidence for neurodevelopmental effects in humans at fluoride water concentrations below 1.5 mg/L;
  o    Uncertainty about the threshold at which adverse effects might start in bone, thyroid or CNS;
  o    Unclear scientific explanation for reported effects, including how fluoride acts and how it moves through the body (kinetics).
• Exposure assessment:
  o    Lack of data on drinking water fluoride concentrations from some EU Member States;
  o    Uncertain fluoride levels in some foods due to limitations of analytical chemistry methods;
  o    Limited data on population exposure from dental care products (amount used, frequency used, amount swallowed).

Taking these uncertainties into account did not increase the likelihood of concern for average consumers.

What are the key recommendations?

• Conducting further research: More studies are required on fluoride's neurodevelopmental effects at water concentration levels below 1.5 mg/L. It is also important to research how fluoride moves through the body (kinetics) and its biological activity.
• Reviewing fluoride drinking water limits: The current legal limit for fluoride in drinking water should be reviewed to make sure it provides adequate protection from potential health risks.

Glossary

Central nervous system (CNS): The brain and the spinal cord.
Neurodevelopment: The process by which the brain and nervous system develop, from the earliest stages of embryonic development to adulthood.
Neurotoxicity: Any adverse effect on the nervous system that results from exposure to potentially toxic substances.
Safe intake level: The maximum amount that can be confidently concluded to pose no risk of adverse effects in the population (EFSA NDA Panel, 2024). For the application of this definition in the case of fluoride, see the Summary section of EFSA’s opinion (see the link below).
Tolerable upper intake level (UL): The maximum level of total chronic daily intake of a substance from all sources that is judged to be unlikely to pose a risk of adverse health effects in humans.

References

EFSA NDA Panel (EFSA Panel on Nutrition, Novel Foods and Food Allergens). (2024). Guidance for establishing and applying tolerable upper intake levels for vitamins and essential minerals. EFSA Journal, 22(11), e9052.

https://doi.org/10.2903/j.efsa.2024.9052

Updated consumer risk assessment of fluoride in food and drinking water including the contribution from other sources of oral exposure.
https://doi.org/10.2903/j.efsa.2025.9478