Fluoride Face-Off: Court Ruling Challenges, but Science Stands Firm
Unpacking the latest legal decision on water fluoridation and why experts still support it
Fluoride is back in the news. A month ago, we reported on a National Toxicology Program (NTP) report that spurred concerns about fluoride being linked to a reduction in IQ in children. (Article linked below.)
I was super honored to have that newsletter picked up by StatNews and have more recently done a couple of interviews with Scripps and the Oregonian on a significant legal development that will be the focus of this newsletter…
A judge said what?
On September 25, 2024, U.S. District Judge Edward Chen ordered the Environmental Protection Agency (EPA) to take further regulatory action regarding fluoride levels in drinking water. This marks the first time a federal judge has acknowledged potential neurodevelopmental risks associated with the recommended U.S. water fluoride levels.
It's crucial to understand what this ruling does and doesn't mean:
The judge did NOT conclude that current fluoride levels are causing lower IQ in children.
The ruling requires the EPA to address potential risks identified in recent studies, including the NTP report.
It doesn't specify what measures the EPA should take.
The ruling is more about ensuring a proper margin of safety than declaring current levels unsafe.
As a public health scientist, I view this ruling as possibly more responsive to public concern than to the current state of scientific evidence. Remember, the NTP report focused on fluoride levels more than double what the EPA currently allows in U.S. drinking water. This perspective is echoed by major health organizations. The American Dental Association (ADA), for instance, has reaffirmed its stance that community water fluoridation is safe and beneficial to oral health, even in light of this recent ruling.
The ADA's expert committee examined the NTP report and concluded that it doesn't provide any new conclusive evidence warranting changes in current community water fluoridation practices. They emphasize that the scientific weight of evidence supporting the benefits of community water fluoridation remains "clear and compelling." The ADA continues to endorse fluoridation of community water as a necessary way to prevent tooth decay and promote oral health, noting that it has been proven to prevent at least 25% of tooth decay in children and adults.
A ‘lil history lesson about water fluoridation
To understand the significance of water fluoridation, we need to look back at the oral health landscape in the early 20th century:
Before fluoridation, dental caries (cavities) were rampant, especially among children.
In the 1930s, researchers noticed that people living in areas with naturally fluoridated water had fewer cavities.
This discovery led to the first controlled water fluoridation experiment in Grand Rapids, Michigan, in 1945.
The results were dramatic: within 11 years, the rate of tooth decay among Grand Rapids children born after fluoridation began had dropped by 60%.
These findings revolutionized public health approaches to dental care, leading to widespread adoption of water fluoridation.
The recommended levels of fluoride in drinking water have evolved:
1945-1962: Initial recommendations based on the Grand Rapids study.
1962-2015: U.S. Public Health Service (PHS) recommended 0.7-1.2 mg/L, varying based on climate and expected water consumption.
2015-present: PHS updated to a single level of 0.7 mg/L for all community water systems, recognizing changes in water consumption patterns and access to other fluoride sources.
World Health Organization (WHO) sets a higher safe limit at 1.5 mg/L, reflecting global variations in natural fluoride levels and differing public health priorities.
EPA's maximum contaminant level remains at 4 mg/L, primarily to prevent severe skeletal fluorosis.
These varying standards reflect the complexity of balancing fluoride's benefits and potential risks across diverse populations and environments.
Geological Factors and Global Variations
It's important to note that fluoride occurs naturally in water sources, with levels varying greatly depending on local geology:
Fluoride is found in rocks and soil and can leach into groundwater and surface water.
Some areas have very low natural levels, while others have very high levels.
High-fluoride areas include parts of China, India, the Middle East, and some regions in Africa.
In the U.S., some areas (e.g., parts of Texas, Oklahoma, New Mexico) have naturally high fluoride levels.
This geological variation is crucial when interpreting studies on fluoride's effects:
Many of the studies in the NTP report were conducted in areas with naturally high fluoride levels (≥1.5 mg/L).
These levels are significantly higher than those used in U.S. water fluoridation programs (0.7 mg/L).
This discrepancy makes it challenging to apply these findings directly to the U.S. context.
So, how does the EPA handle naturally-occurring fluoride?
An important aspect of fluoride regulation that's often overlooked is how the EPA deals with areas where fluoride naturally occurs at high levels. Here's what you need to know:
EPA Regulations:
The EPA sets a maximum contaminant level (MCL) for fluoride at 4.0 mg/L.
There's also a secondary standard of 2.0 mg/L to prevent dental fluorosis.
Monitoring Requirements:
Public water systems are required to monitor and report fluoride levels to state authorities.
If levels exceed the MCL, the water system must notify the public and take action.
Treatment Options:
The EPA doesn't directly remove fluoride from water systems.
Instead, if a public water system exceeds the MCL, they are required to implement treatment to reduce fluoride levels.
Activated alumina adsorption
Reverse osmosis
Distillation
Ion exchange
Community Water Systems' Responsibility:
It's up to the local water utility to implement and maintain appropriate treatment methods.
The EPA provides guidance and enforces the standards, but doesn't directly manage the treatment process.
Challenges:
Removing excess fluoride can be costly, especially for small water systems.
Some communities may rely on alternative water sources or bottled water if treatment isn't feasible.
Ongoing Monitoring:
The EPA continues to study the health effects of fluoride exposure and may update its regulations based on new scientific evidence.
It's worth noting that about 0.6% of the U.S. population (approximately 1.9 million people) are exposed to naturally occurring fluoride levels at or above 1.5 mg/L in their water supply. While this is below the EPA's MCL, it's at the upper limit of the WHO's recommendations and above the current U.S. Public Health Service recommended level for fluoridation.
This situation underscores the complexity of fluoride management in water systems and highlights why the recent court ruling, which calls for further EPA action, could have significant implications for communities with naturally high fluoride levels.
Scientific consensus on fluoride
Despite recent controversies, the scientific consensus still strongly supports water fluoridation:
The CDC named water fluoridation one of the ten great public health achievements of the 20th century.
Numerous studies have confirmed fluoride's effectiveness in preventing dental caries.
Major health organizations, including the WHO, ADA, and AMA, continue to endorse water fluoridation.
The recommended level of 0.7 mg/L is considered safe and effective by most experts.
However, like any public health measure, fluoridation is subject to ongoing research and scrutiny.
Ingested vs. topical fluoride
In discussions about fluoride, a common argument emerges: that we only need topical fluoride (like in toothpaste) and not ingested fluoride (like in water). However, this perspective oversimplifies a complex issue. Let's break it down:
The Argument for Topical-Only:
Some argue that since topical fluoride (in toothpaste, mouthwashes, or dental treatments) is effective and well-established, water fluoridation is unnecessary.
This view often cites the direct action of topical fluoride on tooth enamel and its lower risk of systemic effects.
The Broader Picture:
Complementary Effects:
Research suggests that ingested and topical fluoride work synergistically, providing more comprehensive protection against tooth decay.
Ingested fluoride helps in the development of tooth enamel before teeth erupt, which topical application can't achieve.
Population-Wide Impact:
Water fluoridation reaches entire communities, including those who might not have regular dental care or consistent oral hygiene practices.
It's a passive intervention that doesn't rely on individual behavior, making it particularly effective for public health.
Cost-Effectiveness:
Studies have shown that water fluoridation is one of the most cost-effective public health measures, especially in larger communities.
Continuous Protection:
While topical fluoride provides intermittent protection, fluoridated water offers continuous, low-dose exposure throughout the day.
Historical Success:
The dramatic decline in tooth decay rates since the introduction of water fluoridation can't be attributed to topical fluoride alone.
Current Scientific Consensus:
Most major health organizations support a combined approach of both ingested (water fluoridation) and topical fluoride for optimal dental health.
The CDC, WHO, and ADA continue to endorse water fluoridation as a safe and effective public health measure.
Ongoing Research:
While the benefits of both ingested and topical fluoride are well-documented, research continues to refine our understanding of their relative contributions and optimal use.
Recent studies, including the NTP report, are part of this ongoing process of scientific inquiry and public health optimization.
Understanding this nuanced picture helps explain why, despite the effectiveness of topical fluoride, many public health experts continue to support water fluoridation. The recent legal ruling should be seen in this context – not as a rejection of water fluoridation, but as part of the ongoing process of ensuring its optimal implementation for public health.
Fluorosis: A concern at high doses over time
While the recent ruling focuses on potential neurodevelopmental effects, it's worth noting another well-established effect of excessive fluoride exposure: dental fluorosis.
Dental fluorosis occurs when developing teeth (before age 8) are exposed to excessive fluoride.
Mild cases result in barely noticeable white spots on tooth enamel.
Moderate to severe cases can cause staining, pitting, or roughness of tooth enamel.
It can occur at levels as low as 0.9-1.2 mg/L with long-term exposure during tooth development.
Importantly, the fluorosis associated with regulated water fluoridation is typically mild and considered a cosmetic issue rather than a health concern.
Alternatives: Hydroxyapatite?
As concerns about fluoride have grown, some have turned to alternatives like hydroxyapatite:
Hydroxyapatite is a naturally occurring form of calcium apatite, also found in tooth enamel and bone.
Initial studies show promising results for its use in dental products.
However, it's newer and has less long-term data compared to fluoride.
Hydroxyapatite products are generally more expensive than fluoride-based ones.
We don't yet know its long-term effects or how it compares to fluoride in large-scale public health interventions.
While hydroxyapatite presents an interesting alternative, it's not currently considered a replacement for water fluoridation at a population level.
What does this all mean?
While the judge's ruling doesn't immediately change fluoridation practices, it does highlight the need for:
More studies on the effects of fluoride at levels used in U.S. water fluoridation programs.
Comprehensive risk-benefit analyses.
Continued monitoring of fluoride levels in water sources, especially in areas with naturally high levels.
The EPA's response to this ruling might have particular implications for communities with naturally high fluoride levels.
So what you’re saying is…
Current fluoridation practices remain supported by scientific evidence.
Maintain proper dental hygiene, including the use of fluoride toothpaste.
Consult with dentists or healthcare providers for personalized advice on fluoride use.
More research is needed, particularly at lower exposure levels relevant to most U.S. public water systems.
As we await the EPA's response to this ruling, we'll continue to monitor the situation and provide updates. The goal remains to balance the known benefits of fluoride for dental health with potential risks, ensuring the best possible public health outcomes for all. I will continue using fluoride-based toothpastes (so will my kids) and we will drink our fluoridated water.
BTW, for readers interested in checking the fluoride levels in their local water supply, the CDC offers a resource called 'My Water's Fluoride', though they emphasize that your local water provider remains the most up-to-date and accurate source of information.
Hope this helps make sense of the latest news around fluoride!
xo,
Unbiased Science