In a recent ruling by U.S. District Judge Edward Chen in California, it was stated that fluoride in drinking water can potentially impact the intellectual development of children, urging action from U.S. environmental regulators. While it is not definitively proven that the usual amount of fluoride added to water leads to lower IQ in children, the judge noted that emerging research suggests there is an unreasonable risk of it happening. The Environmental Protection Agency (EPA) was directed by Chen to take measures to mitigate this risk, although specifics were not detailed.
This decision marks a challenge to a long-standing public health practice that has been celebrated as a significant advancement in public health during the last century. According to the U.S. Centers for Disease Control and Prevention, fluoride is beneficial in strengthening teeth and preventing cavities by replenishing minerals lost through normal wear and tear.
Recent findings by a federal agency revealed a potential correlation between increased fluoride exposure and diminished IQ levels in children, based on studies involving fluoride levels exceeding the recommended limit for drinking water by about twice. The EPA, a defendant in the lawsuit, contended that the impact of fluoride exposure at lower levels was uncertain. However, the agency is mandated to ensure there is a safety margin between the hazardous level and the level of exposure.
A spokesperson from the EPA mentioned that they are reviewing the ruling without further elaboration. Since 1950, water fluoridation has been endorsed by federal authorities to combat tooth decay, even after fluoride toothpaste became available. Despite fluoride being sourced from various places, drinking water remains the primary source for Americans, with nearly two-thirds of the U.S. population receiving fluoridated water, per CDC data.
The recommended fluoridation level in water has been set at 0.7 milligrams per liter since 2015, a decrease from the previously advised upper limit of 1.2 milligrams. The World Health Organization has established a safe threshold of 1.5 milligrams for fluoride in drinking water. Separate guidelines from the EPA restrict water systems from exceeding 4 milligrams of fluoride per liter to prevent skeletal fluorosis, a debilitating condition that affects bone health.
Recent studies have indicated a potential connection between fluoride and brain development, particularly concerning developing fetuses and young children who may consume water mixed with baby formula. Animal studies have shown that fluoride could alter neurochemistry and cell function in brain regions linked to learning, memory, executive function, and behavior.
The lawsuit, held in U.S. District Court in San Francisco starting in 2017, was initiated by the non-profit environmental advocacy group Food & Water Watch. Chen halted the case in 2020 to await the National Toxicology Program report’s findings while proceeding with arguments from attorneys earlier this year.