While the judge didn’t declare fluoride outright harmful in all cases, he emphasized that there’s an “insufficient margin” between what’s considered hazardous and the levels many people are exposed to.
The National Toxicology Program (NTP) report reviewed by the court also found that higher fluoride levels (over 1.5 mg/L) are associated with lower IQ in children. This led the court to order the EPA to revisit its regulations.
What Is Fluoride and Why Is It In Water?
Fluoride has been added to drinking water since the mid-20th century to prevent tooth decay. The practice has been praised as one of the greatest public health achievements, significantly reducing cavities, especially in children.
But fluoride isn’t only in drinking water— it’s also found in toothpaste, food, and beverages, meaning people are often getting more than they realize.
What’s the Debate?
While fluoride’s benefits for dental health are well documented, new research suggests that higher levels of fluoride could negatively affect brain development in children. The NTP’s found moderate confidence that fluoride at 1.5 mg/L or higher is linked to lower IQ in children.
This is particularly concerning because, for some children, their total fluoride exposure—including from food and dental products—may exceed these levels, potentially placing them at risk.
The court ruling also noted that for many pregnant women, the fluoride levels in their urine already exceed the hazard threshold of 0.28 mg/L. A study showed that for every 0.28 mg/L increase in fluoride in a pregnant mother’s urine, her child’s IQ could drop by one point.
Given that pregnant women in the U.S. can have urinary fluoride levels as high as 1.89 mg/L, many are already at or above levels which could pose a risk to their children’s brain development.
What Did the Court Say?
The court made it clear that the potential harm to children’s brain development outweighs the benefits of water fluoridation at current levels. As Judge Chen stated, “Not only is there an insufficient margin between the hazard level and these exposure levels, for many, the exposure levels exceed the hazard level of 0.28 mg/L.” In simple terms, fluoride in drinking water is getting too close to—or even exceeding—the levels where it could cause harm.
The EPA argued that the risks were unclear, especially at lower exposure levels, but the court found these arguments unconvincing. The judge pointed out that fluoride doesn’t need to be proven harmful at every exposure level to pose a risk—especially when the safety buffer between fluoride’s dental benefits and potential brain harm is so narrow.
What Happens Next?
The EPA now has to take regulatory action, but the specifics are unclear. They could reduce the amount of fluoride allowed in drinking water or issue warnings to communities with naturally high fluoride levels.
The court didn’t specify what steps the EPA should take, but it’s clear that the current approach isn’t safe enough, especially for vulnerable populations like pregnant women and children.
Is There a Safe Level of Fluoride in Water?
The court’s ruling suggests that there may not be a truly safe level of fluoride in drinking water—at least not one that balances both brain health and dental benefits. The National Toxicology Program found that fluoride levels over 1.5 mg/L are linked to lower IQ in children. For many, the fluoride levels in their water supply, combined with other sources like toothpaste, already exceed that threshold. The choice, as the court suggests, is whether we prioritize brain health or dental health when it comes to fluoride exposure.
Critics of fluoride in water argue that we’re getting enough fluoride from other sources like toothpaste, and point out that many countries have cut cavity rates without adding fluoride to their water. They believe the current levels in U.S. drinking water are too high, especially given the risks to children’s IQ.
What Should You Do?
For now, nothing has changed with fluoride in your drinking water, but it’s a good idea to stay informed.
If you’re concerned, you can look into ways to reduce fluoride exposure, like using filtered water or keeping an eye on the fluoride content of your dental products. Using a hydroxyapatite toothpaste like Fygg is a great way to reduce your fluoride exposure without having to sacrifice the remineralization benefits of fluoride.
The court’s decision may lead to changes in the way fluoride is regulated, but for now, it’s important to weigh the risks and benefits, particularly for pregnant women and young children, who stand to gain the most by reducing fluoride intake and using a hydroxyapatite toothpaste, like Fygg.