Fluoride Action Network

FAN’s Submissions to NTP on Proposed Brain and Cancer Studies

Fluoride Action Network | January 27, 2016

As the Fluoride Action Network reported back in December, the National Toxicology Program (NTP) is planning on conducting an extensive study to investigate fluoride’s effect on the brain, including learning and memory. Unlike the countless government whitewashes on fluoridation that we have seen in the past, we remain cautiously optimistic that the NTP is approaching its fluoride investigation with integrity.

Earlier this month, FAN submitted additional information to the NTP to explain why “high dose” animal studies can be relevant to the neurotoxic risks that vulnerable humans face in fluoridated communities. Fluoridation proponents like to dismiss any animal study that exposes animals to more than 1 ppm fluoride in the water; FAN’s submission explains why this reasoning is superficial and flawed.

The NTP is also currently considering a re-examination of fluoride’s potential to cause or contribute to cancer, including bone cancer (osteosarcoma) in children.  In response to this tentative proposal, FAN submitted extensive information to the NTP, including a detailed discussion of the recent studies that have investigated the relationship between fluoride and osteosarcoma. As we discuss at length in our submission, many of the studies that are cited by fluoridation proponents as disproving the fluoride/osteosarcoma connection had little, if any, power to do so. In fact, when the limitations of these studies are taken into account, some of the studies actually support the fluoride/osteosarcoma link. As we explain, “the current epidemiological evidence linking fluoride to childhood osteosarcoma is much stronger than currently recognized.”

For those interested in getting a better understanding of the recent science on fluoride and cancer, FAN’s submission and accompanying appendices can be accessed here. I particularly recommend the appendices in which Chris Neurath explains the glaring problems with the studies by Kim (2011)Blakey (2014); and Gelberg (1995). Chris also addresses the obvious weaknesses of the studies by Young (2015); Levy (2012); and Comber (2011). Chris did a phenomenal job with these critiques, proving once again why we are so lucky to have him on our team!

The American Dental Association (ADA), which paid $200,000 in lobbying efforts to prevent California from classifying fluoride as a carcinogen, has — not surprisingly — submitted its usual “everything is fine and dandy” info to the NTP, which you can read here.

Finally, we are happy to report that FAN’s comments have attracted the attention of InsideEPA, a journal that provides “relevant news about the federal policymaking process to professionals who have a need to know about the process.” We have provided an excerpt from this article below.

As we did during the National Research Council’s historic three-year review of fluoride toxicity, FAN will continue to closely monitor the NTP’s fluoride studies, and will continue providing the NTP with the best available science on fluoride’s carcinogenicity and neurotoxicity.

Thank you again for your support!

Michael Connett
Executive Director
Fluoride Action Network


Inside EPA

Advocates Back NTP Fluoride Review, Citing Risk To Developing Brain
January 20, 2016

Advocacy groups are backing the National Toxicology Program’s (NTP) plan to evaluate fluoride’s possible neurodevelopmental risks, arguing the review should be a high priority and consider all sources of exposure to the substance, though consumer product and dental industry officials contend current levels of exposure pose no risk.

NTP, part of the National Institute of Environmental Health Sciences, took comment through Jan. 8 on a proposal to review fluoride’s potential neurodevelopmental risks after studies in other countries have found adverse effects to IQ, though the studies were of areas with higher levels of exposure than commonly found in the United States.

In recent comments to NTP, groups including the Fluoride Action Network (FAN) and Parents of Fluoride-Poisoned Children argue fluoride exposures result from multiple sources, ranging from toothpaste to pharmaceuticals, and that numerous studies show the substance poses health risks including to children’s developing brains.

In Jan. 8 comments, the Parents of Fluoride-Poisoned Children say NTP “should place the review of developmental neurotoxicity as a high priority.”

And in Nov. 30 commentsFAN says “a large body of published scientific research … shows that fluoride can damage the developing brain at worryingly modest levels of exposure.” The group also notes that the National Academy of Sciences has identified fluoride as an endocrine disruptor.

During a Dec. 2 meeting of NTP’s Board of Scientific Counselors (BOSC), the advisors backed the NTP Office of Health Assessment and Translation’s plans for a literature review and experimental animal studies to determine the level at which fluoride may pose a risk of neurodevelopmental effects, but questioned the level of resources the project justifies.

Some advisors said the NTP review would face complicating factors, such as estimating exposures given the prevalence of fluoride in consumer products, flaws in published epidemiology studies and difficulties extrapolating risks to humans from animal studies. The panel considered the review a “high to medium” priority.

NTP’s plan to review fluoride’s potential for developmental neurobehavioral effects comes asEPA is reviewing its maximum contaminant level (MCL) for the substance, currently set at 4 milligrams per liter (mg/L). The Safe Drinking Water Act requires EPA to review MCLs every six years to ensure safe levels in drinking water, and says the review should consider “occurrence, health effects and other factors.”

The MCL regulates drinking water systems with high levels of naturally occurring fluoride but does not apply to local decisions to add fluoride to drinking water to prevent dental cavities. The U.S. Public Health Service currently recommends an optimal fluoridation level of 0.7 mg/L.

Environmentalists’ Concerns

Environmentalists have long argued fluoride increases risks of bone damage, and studies in other countries have also flagged the mineral as a potential neurotoxicant, linking fluoride in drinking water to lowered IQ in children. NTP is also considering future literature reviews of other effects possibly linked to fluoride exposure including cancer and endocrine disruption, but those efforts have not progressed as far as the evaluation of neurdevelopmental risks, NTP staff told the BOSC last month.

In comments, FAN calls NTP’s plan to review a potential neurodevelopmental risk for fluoride “warranted and timely,” noting that dozens of studies have found an association between fluoride exposure and reduced IQ.

Specifically, FAN says 23 studies have found reductions in IQ among children consuming water with fluoride levels at or below EPA’s current MCL of 4 ppm. The group also says dozens of animal studies suggest fluoride exposure can impair learning and or memory.

In additional comments, filed Jan. 8, FAN says humans are more susceptible to fluoride exposure than rodents used in animal testing, which require greater amounts of the substance to achieve a similar internal dose.

Officials with the dental and consumer products industries have argued in public comments to NTP that current levels of exposure to fluoride do not pose a neurodevelopmental risk, and that the review is of questionable utility.

A representative of the Consumer Healthcare Products Association told the Dec. 2 BOSC meeting the review could have unintended consequences, such as leading to hazard warnings that fail to account for dose or level of exposure.


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