A new report from the National Toxicology Program (NTP) has linked high levels of fluoride exposure to lower IQ in children, raising fresh concerns about the widespread use of fluoride in drinking water. The report, released on August 21, reviewed 72 studies on fluoride exposure and found that 64 of them showed a significant correlation between higher fluoride levels and reduced IQ scores in children.
The NTP report defined “high exposure” as fluoride concentrations exceeding 1.5 mg/L, a threshold set by the World Health Organization (WHO). In the United States, the Environmental Protection Agency (EPA) allows up to 2 mg/L in drinking water, while the FDA recommends a lower threshold of 0.7 mg/L. According to the report, nearly 2 million Americans receive drinking water with naturally occurring fluoride levels at or above 1.5 mg/L.
The report also indicated that fluoride exposure could be linked to other neurodevelopmental issues, although confidence in those findings was lower due to inconsistent results across studies. The studies included in the review were conducted in 10 countries, including Canada and Mexico, but none were based in the United States.
This research adds to the ongoing debate over the safety and efficacy of fluoride. While fluoride has been credited with reducing tooth decay since it was introduced into public water systems in 1945, concerns persist about its potential risks, especially for children and pregnant women.
Critics argue that the findings should prompt a reevaluation of current fluoridation practices. However, the American Dental Association (ADA) remains steadfast in its support for water fluoridation, citing decades of research that show it reduces cavities by 25% in both children and adults.
The new findings come on the heels of other studies suggesting potential risks associated with fluoride. In May, research indicated that prenatal fluoride exposure may lead to neurobehavioral issues in children, leading some experts to call for a reassessment of fluoride use during pregnancy.
As the debate continues, the NTP’s report could play a key role in shaping future public health policies regarding fluoride exposure.
