The country that started water fluoridation in 1945 is now the place it is being dismantled fastest.
What has happened in the US
- August 2024: the US National Toxicology Program published a systematic review concluding, with moderate confidence, that fluoride exposures above 1.5 mg/L are associated with lower IQ in children.
- September 2024: federal judge Edward Chen found that fluoridation at 0.7 mg/L presents an "unreasonable risk" of lower IQ in children exposed in the womb, and ordered the EPA to act. He noted he was not concluding "with certainty" that fluoridated water harms public health.
- May 2026: the Ninth Circuit Court of Appeals vacated that order, finding the trial judge overstepped by holding the case open for new science. It did not rule on whether 0.7 mg/L is safe, and the EPA is no longer under orders to regulate.
- 2025: Utah became the first state to ban fluoridation of public water (effective 7 May 2025), and Florida followed (effective 1 July 2025).
- October 2025: the FDA moved to restrict ingestible fluoride supplements to children aged 3 and over at high decay risk.
- January 2026: the EPA released a preliminary review of the science on fluoride in drinking water. The legal limit (4 mg/L, set in 1986) has not changed yet.
- June 2026: Louisiana repealed its mandatory state fluoridation program and created a local petition-and-vote process instead of an outright ban.
- Health and Human Services Secretary Robert F. Kennedy Jr has called fluoride "an industrial waste" and a "dangerous neurotoxin", and the EPA has announced a review of fluoride in drinking water.
The Australian response
The NHMRC, state health departments, the Australian Dental Association and the Australian Medical Association all continue to support fluoridation. They point out that the NTP's findings relate to levels above what is added in Australia (0.6 to 1.1 mg/L), and that Australian studies have not found an IQ effect.
Critics counter that the margin between Australian dosing and the levels studied is not large, that people's total fluoride intake also comes from toothpaste, tea and food, and that infants on formula made with tap water receive proportionally more.
What it means here
In Australia, fluoridation is a state and council decision, not a federal one. That is why Queensland looks so different from Victoria. The US shift has not changed any law here, but it has changed the conversation, and the NHMRC's decision to reopen its own advice in 2026 shows the evidence is being looked at again.