TSCA Fluoride Lawsuit


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Under the Toxic Substances Control Act (TSCA) of 1976, a group of non-profits and individuals petitioned the U.S. Environmental Protection Agency (EPA) in 2016 to end the addition of fluoridation chemicals into U.S. drinking water due to fluoride's neurotoxicity. The EPA rejected the petition. In response the groups sued the EPA in Federal Court in 2017. Evidence on fluoride’s neurotoxicity was heard by the Court in two phases: a 7-day trial in June 2020, and a 14-day trial in February 2024. As of May 2024, a judgment from the court has yet to be rendered.

Official Court link: Food and Water Watch et al. v. United States Environmental Protection Agency et al.


Lawsuit Team

The Petition

In 2017, Dr. Paul Connett PhD and Dr. Bill Hirzy PhD, on behalf of the Fluoride Action Network (FAN), Food and Water Watch (FWW), Moms Against Fluoridation (MAF), as well as several individuals, served the EPA with a petition calling on the agency to ban the addition of fluoridation chemicals to public water supplies due to the risks these chemicals pose to the brain.


The Petition was submitted under Section 21 of the Toxic Substances Control Act (TSCA) because it authorizes EPA to prohibit the “particular use” of a chemical that presents an unreasonable risk to the general public or susceptible subpopulations. TSCA also gives EPA the authority to prohibit drinking water additives.


Dr. Connett and Dr. Hirzy deliver the petition to
EPA Headquarters in Washington, D.C.

The Initial Hearings

EPA denied the petition on February 27, 2017, claiming that: “The petition has not set forth a scientifically defensible basis to conclude that any persons have suffered neurotoxic harm as a result of exposure to fluoride in the U.S. through the purposeful addition of fluoridation chemicals to drinking water or otherwise from fluoride exposure in the U.S.” FAN and other plaintiffs then sued the EPA and won a series of favorable court hearings in 2017 and 2018 on plaintiff’s standing and trial discovery, while defeating several motions by EPA attempting to dismiss the case.


In late 2019 both FAN and EPA submitted motions for summary judgment in the case in the hopes that the judge would rule on the evidence submitted to the court without the need for a lengthy trial. On December 30, 2019 the Court released its order denying both plaintiffs’ and defendant’s motions for summary judgment. This means that our case will go forward. Trial is scheduled for two weeks beginning April 20, 2020 and will run for two weeks.


Attorney Michael Connett: “this is the first time in its 43-year history that citizens
have been able to successfully bring a suit to court under provisions in TSCA”

Pre-Trial

On March 17, 2020 the Court postponed the April 2020 fluoride lawsuit trial dates due to the coronavirus outbreak. The trial will now be held June 8-19 by Zoom webinar (instead of in person at the courtroom).


In a May 2020 pre-trial hearing, the Court cleared the way for three international experts in neurotoxicity (Dr. Howard Hu, Dr. Philippe Grandjean, and Dr. Bruce Lanphear) to testify on the risks of fluoride in public water supplies on behalf of the plaintiffs. The court also ruled that the purported benefits of community water fluoridation cannot be part of the trial, restricting testimony to the toxic risks under the Toxic Substances Control Act (TSCA) Read the May 2020 trial declarations from our 4 witnesses:


Philippe Grandjean, MD, PhD

Howard Hu, MD, MPH, ScD

Bruce Lanphear, MD, MPH

Kathleen Thiessen, PhD

The First Fluoride Trial (June 8 - 19, 2020)

The first trial in the TSCA fluoride lawsuit took place in June 2020 over Zoom webinar. The trial lasted two weeks and featured testimony from FAN’s expert witnesses (Drs Hu, Lanphear, Grandjean, and Thiessen) who are subject matter experts on developmental neurotoxicity and risk assessment, pitted against EPA’s witnesses.


Shockingly, EPA did not rely on its own agency experts to defend its position that fluoride is not neurotoxic to humans. Instead it hired an outside consulting company, Exponent, a firm deployed by corporations to deny and downplay the health impacts of chemicals in litigation. Exponent experts attempted to cast doubt on fluoride’s neurotoxic effects even as the EPA’s own scientists, under subpoena by the plaintiffs, said new research does indeed warrant “an update to the fluoride assessment”.

"I think it's a reason for doing an update to the fluoride assessment" - Dr. Joyce
Donohue, EPA Office of Water, on recent NIH-funded studies showing fluoride
harms the developing brain.

FAN attorney, Michael Connett, gave the opening statement in the trial - a summary of the case that fluoride presents a neurotoxic hazard (a threat to the brain); that this hazard is a risk at doses experienced in fluoridated communities (.7ppm); and that this risk is an “unreasonable risk” as defined by TSCA. The EPA is represented by lawyers from the Department of Justice (DOJ). The DOJ argued in their opening statement that establishing fluoride as a neurotoxic hazard requires a systematic review and without that, FAN’s case falls.


The first fact witness called by the plaintiffs (FAN) was Dr. Joyce Donohue who has worked in the EPA’s Office of Water since the 1996 and has been their spokesperson on fluoride. Her testimony in the trial was based on a video recording of her deposition in 2019. From this deposition our attorney was able to yield two key concessions:


a) The EPA as of 2019 had no studies to provide a pregnant woman to show her fetus was safe from neurotoxicity. In fact the EPA only had studies showing harm to the fetus.


b) Dr. Donohue recommends EPA and other regulatory bodies do risk assessments of fluoride with neurotoxicity as an end point. All EPA risk assessments on fluoride to date have been based on potential damage to teeth and bones.


FAN’s first expert witness called was Dr. Howard Hu, MD, MPH, ScD, the lead author on a series of key NIH-funded research papers on fluoride and developmental neurotoxicity. Hu’s credentials are very impressive. Dr. Hu came across as knowledgeable and credible and was able to summarize the importance of his research, stressing the importance of a loss of 3 or 4 IQ points at the population level while drawing a striking parallel to lead’s neurotoxicity.

FAN’s second expert witness, Danish scientist and neurotoxicity expert Philippe Grandjean, MD, DMSc, took the stand on day two. Grandjean is the author of the book Only One Chance, in which he warns of the dangers of exposing children to neurotoxicants during early development, especially during the fetal stage. According to many who watched his testimony, Dr. Grandjean left no doubt that fluoridation poses a threat to the brains of children and easily debunked the EPA’s paid experts’ arguments.

FAN asked Dr. Grandjean to do a review of the literature since his famous 2012 meta-analysis to include the most recent US government-funded studies. Grandjean did this review but he went one step further and quantified the risk of IQ loss from fluoride to children based upon the Bashash 2017 and the Green 2019 (Canadian study) mother-offspring studies. For this analysis Grandjean did what is called a Benchmark Dose study (using methods that he and his colleagues have pioneered, and used by the EPA). He concluded that a safe reference dose (RfD) be no higher than 0.15 mg per day to protect against a loss of one IQ point. This is well below fluoride exposure levels experienced by pregnant women (and passed to the fetus) in the Bashash and Green studies.

FAN’s next expert witness was renowned clinical scientist and professor, Dr. Bruce Lanphear… who’s work on lead…..  Dr. Lanphear explained that there was no safe level of fluoride exposure with regard to neurotoxicity, and that the effects seen in recent studies are “equal to what we saw with lead in children.”

Next the court watched the deposition video of CDC Oral Health Division Director, Casey Hannan, who confirmed his agency agreed with the National Research Council’s 2006 findings that fluorides “interfere with the function of the brain and body by direct and indirect means,” among many other stunning admissions, yet did nothing to act upon or study these findings.

Next up in the trial was fact witness Dr. Kristina Thayer, Director of the US EPA’s Chemical and Pollutant Assessment Division. Dr. Thayer confirmed the vulnerability of the developing brain to environmental toxins as well as fluoride’s known neurotoxicity “at some level.”


The next expert witness was veteran risk assessment scientist Kathleen Thiessen, PhD, who was a member of the 2006 NRC committee that reviewed fluoride, and authored around a third of the report. Dr. Thiessen confirmed that the EPA was ignoring the neurotoxic risk from fluoridation because doing so would require them to effectively ban the practice. She also compared the amount of evidence of neurotoxicity from fluoride to other toxins the EPA currently did regulate as neurotoxic, saying “the amount of evidence for fluoride is considerably larger.”

The EPA then called their first expert witness, Dr. Joyce Tsuji, PhD from corporate consulting firm Exponent.  This is the same scientists-for-hire firm the tobacco industry used to deny lung cancer risk. Dr. Tsuji’s answers repeatedly contradicted the testimony from her pre-trial deposition. Eventually FAN attorney Michael Connett was able to get Dr. Tsuji to admit on the stand that “there is enough literature for us to be concerned” about fluoride’s neurotoxicity.


The EPA then called their second expert witness, Dr. Ellen Chang (also from Exponent), to discuss the human fluoride/IQ studies. She spent much of her time attacking the quality of the studies linking fluoride to lowered IQ. FAN attorney Michael Connett was successful in exposing Dr. Chang’s blatant bias and, in a defining moment at trial, was able to get her to admit that the fluoride/IQ studies from Till (2020), Green (2019), and Bashash (2017) were the most rigorous neurotoxicity studies to date.


Next up was Dr Tala Henry, Director of the EPA’s Risk Assessment Division, who has 25 years of risk assessment experience at the agency. Her testimony focused on the many hurdles presented to those who attempt a risk assessment and risk evaluation of a chemical. FAN’s attorney Michael Connett dealt a destructive blow to Dr. Henry during cross-examination came when he asked: “you held the plaintiffs to a burden of proof that EPA has not held a single chemical under section 6 [of the Toxic Substances Control Act] before, correct?”.  Henry replied, “by the words on the page, I guess that’s true”. The EPA closed its case with a short video segment of Dr. Joyce Donohue, the predominant fluoride expert in the EPA’s Office of Water.  If anything, this video strengthened our case and did not weaken it.


The last day of trial featured a dramatic moment, as the federal judge surprised everyone by recognizing the key plank in our case, undermining the key argument in the EPA’s case. The judge said:

“So much has changed since the petition was filed…two significant series of studies – respective cohort studies – which everybody agrees is the best methodology. Everybody agrees that these were rigorous studies and everybody agrees that these studies would be part of the best available scientific evidence.”

The EPA appears to have applied a standard of causation, which from my read of TSCA is not accurate. It’s not a proper allocation. It’s not the proper standard.’


After closing statements, Judge Chen shared his views on the case and made recommendations. Chen asked the parties whether they could discuss the possibility of an amended petition and re-assessment by the EPA, or start a new petition and have the EPA conduct a proper review. To many observers, it felt as though Chen was intimating that FAN had essentially won the case, but he was giving the EPA a chance to right their original wrongs.


The ending of the first fluoride trial was somewhat unexpected as the judge asked the two parties to work out an agreement. The Court specifically urged the EPA to independently re-assess the hazard posed by fluoridation chemicals and the Judge assigned August 6, 2020 for a status hearing to reconnect with the two sides. When the parties met on August 6, EPA claimed that they “didn’t have the resources to do a risk assessment,” and were going to let the court record stand without taking any further action.  The judge continued to insist the EPA reconsider their position, and also said he wanted to review the updated National Toxicology Program’s (NTP) review of fluoride’s neurotoxicity, which was due to be released soon.


In August 2020, the Court placed the case in abeyance (on hold) in part to consider the pending findings from the pending NTP report on fluoride neurotoxicity.

Justice Delayed

The Court requested on the last day of the trial that FAN submit a new petition to the EPA to allow them another 90-day opportunity to respond to our original 2016 petition with the addition of all the new studies on fluoride neurotoxicity published between 2017-2020. The Court also requested that FAN include petitioners who were pregnant or planning a pregnancy in light of the science linking early-life exposure to fluoridated water to adverse neurodevelopmental effects in these new studies.


On November 4, 2020, FAN filed a supplement to our original petition to the EPA. The supplement asked that EPA reconsider their denial of our 2016 Petition. The supplement has done everything the Court asked us to do with a new petition. The supplement also responds to the issue of standing by identifying nine members of Food & Water Watch “who are currently pregnant, women who are actively seeking to become pregnant, and/or mothers of infants”.


In December 2020, the EPA filed a last ditch motion to attempt to dismiss our landmark case, arguing that plaintiffs lacked standing; a motion they had previously made and were denied. The Court denied the EPA motion as being premature and procedurally improper. The trial will continue, in abeyance, as the Court awaits the EPA’s response to FAN’s updated petition and an updated draft of the National Toxicology Programs (NTP) monograph on fluoride’s neurotoxicity, expected early in 2021.


In January 2021, the EPA denies FAN’s supplemental petition, setting the stage for additional hearings and filings in the TSCA fluoride lawsuit. An April 2021 status hearing with the Court focused on FAN’s amended petition to the EPA, which the Judge recommended before he placed the trial in abeyance. The amended version has a more detailed list of plaintiffs and includes recent studies that were not a part of the trial. The Court grants FAN’s motion to supplement our pleadings to introduce additional evidence on standing, which should satisfy the Judge’s prior concerns on this issue and ensure that the case is resolved on the merits.


The Judge reiterates that he is keen to read the NTP’s finalized report on fluoride’s neurotoxicity as well as other new science on the issue, including an upcoming pooled analysis of the NIH-funded birth cohort studies. To consider this new science, the Judge discussed having a “phase 2 trial” where Plaintiffs and EPA can introduce additional expert testimony on the NTP report and other developments. In June 2021, FAN attorney Michael Connett informs the Court of a new landmark study by Grandjean et al., confirming that very low levels of fluoride exposure during pregnancy impairs the brain development of the child. The paper’s authors concluded in the Benchmark Dose (BMD) analysis that a maternal urine fluoride concentration of 0.2mg/L was enough to lower IQ by 1 point. The judge was waiting to see this analysis as well as the final version of the NTP review before moving forward with the case.


In a January 2022 status hearing, the Judge reiterates his desire to wait until the NTP publishes the final version of their review on fluoride’s neurotoxicity before continuing with the trial. The NTP report had been delayed, with speculation brewing that dental interests were actively influencing the report’s final publication.


In September 2022, FAN filed a motion to lift the pause on the trial in response to the indefinite postponement of the NTP fluoride review. The final publication of the NTP review was expected at the end of 2021, then promised again in early 2022, with May 2022 being the long-awaited release date. May 2022 came and went without any sign of the NTP report.


In October 2022, FAN attorney Michael Connett introduced evidence from Freedom of Information Act (FOIA) documents showing that political pressures had prevented NTP from releasing its long-delayed report [link to new NTP page]. The Court promptly granted our motion to lift the stay on the trial and permit additional discovery into the NTP review.


EPA’s objections to using any version of the NTP report besides the “final” version during the trial was based on their concern that the NTP’s findings would be made public prematurely. To circumvent this objection, the Court placed the NTP’s review under protective order so that it was only made available to the parties involved, the Court, and expert witnesses. The Court urged both parties to come together and find a way to get the current NTP review into the Court’s hands “voluntarily,” while also leaving the door open for FAN attorney Michael Connett to use “subpoenas or a motion to compel,” the release of the long-delayed report.


In December 2022, after extensive negotiations, the Department of Justice (DOJ) agreed to produce a copy of NTP's suppressed report on fluoride. The report is produced under a strict protective order.

FAN Attorney Michael Connett shared with the Court FAN’s desire to see the final NTP review from May 2022 available to the public, as well as the communications and criticisms from the CDC and HHS that led to it being blocked. Connett pointed out that FAN had evidence obtained through FOIA requests showing that the American Dental Association (ADA) was already given the NTP review so they could work to discredit it, and therefore there is no justifiable reason for the EPA to continue hiding it from the public.


In January 2023 the Court ruled against EPA’s request for additional delay of the trial, acknowledging that “justice delayed is justice denied”. The Court sets a timeline for the final phase leading to a verdict.


In February 2023, after being served a subpoena by our attorneys, the NTP agreed to publicly produce their final report that was intended to be published in May of 2022, along with communications between various federal agencies and the NTP about the report. This allows the public to finally see the report and accompanying documents that were blocked from being published by the leadership at U.S. Health and Human Services (HHS) in May of 2022. Internal CDC emails discovered through FOIA by FAN show that the publication was blocked at the last second due to interference from Assistant Health Secretary, Rachel Levine.

The NTP fluoride review was issued in two parts, a monograph and a meta-analysis. The meta-analysis found that 52 of 55 studies found lower IQ with higher fluoride exposures, demonstrating remarkable consistency. Of the 19 studies rated higher quality, 18 found lowering of IQ. The meta-analysis could not detect any safe exposure, including at levels common from drinking artificially fluoridated water.


In March 2023 the Court denied EPA's motion to prevent FAN from conducting depositions into the suppression of the NTP report. Dates are set for the final phase of the TSCA fluoride lawsuit - January 29 thru February 13, 2024.


FAN learned at an October 2023 status hearing the start date for the last phase of our fluoride trial would be pushed back two days to January 31st, 2024. The expiration of the CARES Act means that our attorneys will present live, in-person from the federal courthouse in San Francisco during the second phase of the trial. The trial will be live streamed on Zoom for the public to view.


In a January 2024 pre-trial hearing, FAN attorney Michael Connett introduced evidence that key a EPA witness lied under oath.

The Second Fluoride Trial (January 31 – February 20, 2024)

The second trial in the TSCA fluoride lawsuit took place January 31 – February 13, 2024, at the Federal Courthouse in San Francisco and was live-streamed on Zoom. The trial lasted two weeks and featured testimony from the same FAN expert witnesses seen in the first fluoride trial – Drs. Hu, Lanphear, Grandjean, and Thiessen.

Lawsuit Team

FAN attorney Michael Connett gave the opening statement in the second fluoride trial, laying out key evidence in the case against fluoride, including EPA documents showing that the neonatal stage is critical to brain development and vulnerable to neurotoxins. Connett pointed out that fluoride’s transfer from the mother to the fetal brain was an undisputed fact agreed upon by both parties, as were fluoride’s neurotoxic effects on fetal and infant brain development. Connett described how several of the EPA’s own employees agreed under oath with the assessment that fluoride is a neurotoxin.


Central to the crux of the case, Connett focused on EPA’s admittance that they did not use the appropriate EPA guidelines in their risk evaluation of fluoride and did not follow the Toxic Substances Control Act (TSCA) statutes when evaluating whether fluoride posed an unreasonable risk to the developing brain. Not only did EPA fail to follow TSCA and agency risk assessment rules, but they went further by admitting that they held fluoride to a higher standard than any other chemical. This included the EPA’s insistence in discounting high-dose fluoride studies, while EPA has never disregarded higher-dose studies when identifying a hazard with any other chemical.


Connett also honed in on the National Toxicology Program’s (NTP) systematic review of fluoride neurotoxicity, and a large body of animal data showing brain harm from fluoride. The NTP review found a large number of studies have been published on fluoride and human IQ. In total they identified 72 human studies of which 64 found a connection between fluoride and IQ deficits. 18 of the 19 studies deemed high quality found that fluoride lowered IQ, a 95% consistency. Connett flagged recent research relied upon by EPA that did not find neurotoxic effects from fetal fluoride exposures as deeply suspicious. He said the authors of these studies were long-time promoters of water fluoridation, compared to FAN expert witnesses, who have all worked with the EPA and have been relied upon as experts on the regulation of environmental toxins by governments around the world and are subject-matter experts on fluoride.


Connett discussed how the exposure level at which a chemical presents a risk for toxic effects (a threshold level) varies substantially across the human population, but the point of a regulatory action is to protect the most vulnerable people in the population. Connett stressed to the Court that “TSCA commands us to protect the vulnerable”. Connett then wrapped up by pointing out that roughly two million pregnant women and 400,000 formula-fed babies exposed to fluoride in water are at risk and that TSCA requires the EPA to consider injuries that chemicals pose to sensitive and highly exposed people. The EPA focused their opening statement on the talking point that “the dose makes the poison,” suggesting, in contrast to the actual published research, that there is insufficient compelling evidence that fluoride is a neurotoxin at the current levels used for fluoridation in the U.S. and that therefore water fluoridation doesn’t pose a risk to children. EPA named the expert witnesses it will call in the case: David Savitz, Ph.D., who chaired NASEM’s committee that peer reviewed the NTP’s systematic review; EPA risk assessment expert, Stan Barone, Jr., PhD; and and Jesus Ibarluzea, PhD, authored of the flawed “Spanish” study.


FAN attorney Michael Connett then called our first expert witness to the stand, Howard Hu, MD, MPH, ScD. Dr. Hu has authored more than 320 papers in peer-reviewed journals and published several landmark studies on fluoride and the brain. He also advises the EPA and collaborates with its scientists on issues related to lead exposure.


Connett asked Dr. Hu how he would compare the peer review process that his fluoride studies underwent with other studies he’s published. Hu responded that his fluoride studies are “probably the most extensive peer review process I’ve experienced.” Hu also discussed his concerns about the Spanish study the EPA used as a basis to argue fluoride is not toxic at low levels, and criticized the EPA’s opening statements, saying that the EPA was presenting data as black and white.


Hu then compared his Canada MIREC cohort study and Hu’s more recent MADRES cohort study from the U.S. Both indicate higher levels of fluoride in the urine of pregnant mothers in the third trimester. Hu remarked that the third trimester increase is reminiscent of what we saw with lead: fluoride is stored in the mother’s bones and during the third trimester, when fetal bone growth accelerates, the mother’s body transfers calcium from her bones, along with any present toxins like fluoride, to the fetus.


Dr. Hu was interviewed by independent journalist Derrick Broze after the first day of court adjourned:

Next up was FAN expert witnesses Bruce Lanphear, MD, MPH, who has studied the impact of toxic chemicals, including lead and pesticides, on children’s brain development for over 20 years. Lanphear testified that his research has been almost exclusively funded by federal agencies, including the EPA and the Centers for Disease Control and Prevention (CDC). In fact, Dr. Lanphear’s research was cited by the EPA as the principle study upon which the agency based its current regulatory standards for lead in air and water.


Lanphear discussed the findings and methodology used for several landmark human studies funded and vetted by the National Institutes of Health (NIH) on fluoride and the brain that he co-authored. Lanphear stated that out of the 350+ studies he’s published, his study was one of the two most rigorously reviewed and scrutinized studies prior to publication in his career due to the “implications for public health policy.” His study found a linear dose-response relationship between fluoride and IQ, meaning that the lowered IQ effect occurred with any level of fluoride exposure and increased as the exposure increased.


There was then discussion of another study he co-authored which found that consumption of infant formula reconstituted with fluoridated water led to excessive fluoride intake and lower IQ scores for both boys and girls compared to their breastfed counterparts who received very low intakes of fluoride. Lanphear also pointed out that studies have consistently found that children in poorer areas were often exposed to more toxins, and the effects of fluoride exposures for their mothers during pregnancy and for the children during formula feeding could compound these effects, making the poor particularly vulnerable to fluoride’s effects.


In his testimony, Lanphear addressed the variability of findings in different studies - some find sex-differentiated responses to fluoride and others don’t, or some find neurotoxicity at lower levels and some at higher levels. Lanphear said that the same variability exists in toxicity studies for lead, where some studies find greater effects in boys and others in girls. The overall indication is that lead, like fluoride, is toxic and that other factors drive sex differentiation in a particular context.


The discussion then focused on how fluoride could increase hypothyroidism rates in pregnant women, impacting fetal brain development, and how these effects were both increased if the mother was iodine deficient. Lanphear co-authored key studies on these subjects. He pointed out that the 2006 National Research Council report recognized that fluoride was a thyroid disruptor. He also noted that iodine deficiency has been increasing in the United States. FAN attorney Michael Connett asked, “Is there any dispute that hypothyroidism can lead to a lower IQ?” Lanphear: “No.”


Lanphear wrapped up his testimony by discussing his work measuring maternal urinary fluoride concentrations of pregnant women. He testified that an average woman living in a fluoridated community has fluoride levels in their urine twice as high as an average woman living in a non-fluoridated community. Connett asked, “What is the cause of this difference?” Lanphear responded, “Fluoridated drinking water.”


Journalist Derrick Broze interviewed Dr. Lanphear after his testimony on day two of the trial:

The third expert witness called by FAN was Philippe Grandjean, MD, DMSc. Dr. Grandjean is a physician, a scientist, an internationally known expert in environmental epidemiology, an author, and both a professor of environmental health at the Harvard School of Public Health and the head of the Environmental Medicine Research Unit at the University of Southern Denmark.


Grandjean testified that he has been given grants and/or contracts to advise the EPA, the National Institutes of Health (NIH), the U.S. Food and Drug Administration (FDA), the World Health Organization (WHO), and numerous other government bodies for over 25 years. Dr. Grandjean said he had even been retained by the Department of Justice, which is representing the EPA in our trial, as an expert witness on environmental toxins.


Grandjean is the author or co-author of some 500 scientific papers and is perhaps best known worldwide for his research on the neurotoxicity of mercury, which involved studying the IQ of children born to mothers whose diet was high in mercury. This work led to defining the EPA’s safe regulatory levels for mercury in the diet and inspired downward revisions of methyl mercury exposure limits internationally.


Dr. Grandjean has authored or co-authored several studies and reviews on fluoride’s neurotoxicity, as well as the first benchmark dose analysis on fetal fluoride exposure which found that a maternal urine fluoride concentration of 0.2 mg/L, which studies show is exceeded 4 to 5 times in pregnant women living in fluoridated communities, was enough to lower IQ by 1 point. In his testimony, Grandjean confirmed that the fluoride the mother is absorbing will pass into the child’s brain. “You only get one chance to develop a brain. Once it’s harmed, there’s nothing you can do.” Grandjean says.


Attorney Connett showed a quote from EPA scientist Kristina Thayer, who provided testimony in the first phase of the trial. Dr. Thayer said she believes that animal data supports the biological plausibility of fluoride causing neurotoxic effects in humans. Grandjean agreed with Thayer’s opinion. Connett asked Grandjean about the EPA’s opening statement in which they claimed that Chinese fluoride studies were looking only at very high levels of fluoride exposure. Grandjean insisted this was not the case, saying that even at lower levels there was evidence of cognitive impacts from fluoride, confirming outright that he felt neurotoxicity was definitely a hazard of fluoride exposure.


Connett then asked about NTP’s May 2022 final draft report, which included Grandjean’s own studies and found lower IQ in children exposed to fluoride during fetal development. Connett specifically asked about the EPA’s claim that the NTP’s findings were “driven by studies looking at fluoride levels of 7.0 ppm and higher.” Dr. Grandjean replied, “They must have a misunderstanding because that’s certainly not correct.” He then agreed with the NTP authors’ statements that some of the higher-quality studies that found harm were done in optimally fluoridated communities.


Dr. Grandjean then confirmed that over a lifetime of dealing with evidence on neurotoxicants, “Fluoride probably has the largest body of evidence of any of our known or suspected neurotoxicants.” Agreeing with NTP’s finding that the consistency of association of lower IQ in children in five different countries rules out the possibility that there is a common factor other than fluoride exposure that can account for this outcome, Dr. Grandjean stated: “When it comes to fluoride, we have a massive amount of evidence. There is something very serious going on here that we must take seriously.”


Journalist Derrick Broze interviewed Dr. Grandjean after his testimony on day three of the trial:

Next to take the stand was EPA’s expert witness Stanley Barone, Ph.D., a risk assessment scientist from the EPA Office of Chemical Safety and Pollution Prevention, testifying as FAN’s fact witness to establish EPA’s methods for risk evaluation under the Toxic Substances Control Act(TSCA).


Through questioning, Barone explained the EPA’s risk assessment method - the method FAN says EPA is failing to apply in the case of fluoride. As an EPA developmental toxicologist, Barone was heavily involved in TSCA’s first 10 risk evaluations. Before the trial, the plaintiffs asked Barone to establish the risk evaluation process for the record.


Connett questioned Barone on key elements of the hazard assessment. He asked Barone to confirm that to determine whether a chemical is a hazard - step one in the risk assessment process - there is no need to prove causation. Barone agreed that to establish that a chemical is a hazard, EPA requires proof of association, not causation.


Next, Connett asked Barone whether EPA had ever made a different hazard evaluation for high-dose versus low-dose exposure in any of the risk evaluations it had done to date under TSCA. Barone said he was confused by the question. Judge Chen interjected to pose the question himself. “In the hazard evaluation, is it a binary decision?” Barone said it was. In other words, a chemical poses a hazard or it doesn’t. The EPA doesn’t differentiate between high and low doses in determining whether something is a hazard. Barone also confirmed that once something has been confirmed as a hazard, medium- and high-quality studies are then used to identify a hazard level. These are points our attorney laid out in his opening remarks.


In what would become a defining moment in the trial, Dr. Barone testified that in his estimation we should have a margin of safety of at least 10x for fluoride to protect the most vulnerable in society. The current margin of safety between fluoridated water at 0.7 ppm and the level that NTP found neurotoxicity, 1.5 ppm, is only 2x. EPA would backpedal from this admission throughout the rest of the trial. Some observers might say this moment forced the EPA to change strategy mid-trial. 


FAN attorneys then called to the witness stand Dr. Brian Berridge, DVM, DACVP, Ph.D., who oversaw the completion of the NTP’s work, to discuss the NTP fluoride review and the peer-review process.


In December 2023, EPA moved to exclude Berridge’s testimony from the trial, arguing it would speak to the political influence exerted to stop the NTP report’s publication, rather than to the scientific findings in the report, which are central to the trial. EPA attorneys argued Berridge’s testimony would be “unfairly prejudicial” to the agency. Although Berridge commented in an email, obtained by FAN via a FOIA request, that there was an ongoing attempt to modify the report to satisfy interested actors and to obstruct its publication, FAN did not call on him to speak to that issue, but rather on the integrity of the scientific process in the report’s production. In a blow to EPA, Judge Chen said he woul allow Berridge’s testimony.


Dr. Berridge testified at trial that he signed off on the May 2022 version of the NTP fluoride review as a final and complete report that was ready for publication.


Read more: What Dr. Berridge Couldn’t Tell The Court


FAN Attorney Michael Connett then called veteran risk assessment scientist, Dr. Kathleen Thiessen as the next expert witness. Connett establishes that Dr. Thiessen is the author of a large portion of the 2006 NRC fluoride review, and that she also worked on the 2009 review. Connett asked Thiessen if there is any reasonable doubt that neurotoxicity is a hazard of fluoride exposure. Thiessen replied that “neurotoxicity is a hazard of fluoride exposure, the evidence is abundant”.


Connett then asked several questions comparing the NTP review process to the EPA review process, Thiessen says the EPA has not been as open and transparent. That the NTP's communication of its conclusions about fluoride's toxicity was more transparent. 

Dr. Berridge

Day six of the second trial in the fluoride lawsuit started off with a bang, as FAN attorneys shared with the Court a new systematic review by Canadian researchers, published the night before, linking fluoride exposure at very low levels to lower IQ in children.


Canada’s public health agency, Health Canada, commissioned a team of scientists to study the effects of fluoride on human health, but the agency did not publish the review. The peer-reviewed journal Critical Reviews in Toxicology instead independently published the study. The researchers calculated the “point of departure” for the effects of fluoride on IQ - also known as the “hazard level,” the lowest point at which a toxic effect is observed - and found it to be 0.179 milligrams per liter (mg/L) in water.


Levels of fluoride found in drinking water in the U.S. and Canada typically are in the higher range of 0.7 mg/L. The NTP report set the hazard level at 1.5 mg/L, and one of the key studies at the center of the trial set the level even lower than 0.2 mg/L.


Even at a hazard level of 1.5 mg/L, exposure levels for fluoride carry significant risk under TSCA’s guidelines, but this new level identified by Canadian researchers would set a risk level even further below current exposure levels.


The findings are important to the trial because the identified hazard level was quite low and also because the authors calculated their hazard level in terms of water fluoridation levels, which they extrapolated from the urinary fluoride levels used in most studies.


The findings also are significant because David Savitz, Ph.D., professor of epidemiology at Brown University and the EPA’s first witness, was part of the expert panel that advised Health Canada on how to interpret this study and other data. The expert panel that included Savitz concluded there wasn’t enough evidence to lower the amount of fluoride in drinking water based on its neurocognitive effects.


Next, EPA’s first key witness, David Savitz, Ph.D. took the stand. Dr. Savitz is a professor of epidemiology at Brown University School of Public Health. He worked with the National Academies of Sciences, Engineering, and Medicines (NASEM) in reviewing the draft NTP fluoride report.

Dr. Savitz

Over nearly three days of testimony, Savitz downplayed the link between fluoride and IQ loss in children. Savitz’s testimony supported the EPA’s three key arguments:

  • Data on fluoride’s neurotoxic effects for children at current levels of water fluoridation is mixed or uncertain and therefore no action should be taken.
  • There are limitations to the NTP’s conclusions, published in draft form last year, linking fluoride exposure and IQ loss in children at 1.5 milligrams per liter (mg/L).
  • More recent studies not considered by the NTP cast doubt on the NTP’s findings.

However attorney Michael Connett and even Judge Chen pushed back on his conclusions. Connett underscored in his cross-examination that Savitz is an expert in epidemiology but has no experience researching fluoride.


Savitz testified that the Health Canada panel he was on determined that data showing IQ loss in children at existing water fluoridation levels contained too much “uncertainty” to set a hazard level for drinking water, so they advised Health Canada not to change its fluoridation levels.


Under cross-examination, Savitz told the court he sat on that panel at the same time that the EPA was paying him $500 per hour — totaling between $137,000 to $150,000 for 275-300 hours of work — as a litigation expert for the EPA in this trial examining that very question. Judge Chen asked Savitz if Health Canada knew he was serving as an expert witness in this case when they invited him to the panel. Savitz said the agency did.


Regarding his work reviewing the NTP fluoride report, Savitz said NASEM determined the first draft of the NTP’s report, which classified fluoride as a neurotoxin, fell short of providing “a clear and convincing argument” that supported its assessment. Savitz told the court he didn’t think NTP’s conclusions were “wrong” but that they were stated in a way that could be “misused” as a tool for setting or changing water policy on water fluoridation. Savitz said he thought that after the revisions, the communication was “tempered” and “more consistent”.


Savitz testified that because two of the four major cohort studies discussed in the trial (MIREC and ELEMENT), found a statistically significant effect of fluoride on IQ at low levels, and two did not (Odenseand INMA), there was too much uncertainty to definitively conclude that it posed a danger at current levels of water fluoridation. Judge Chen asked, “I take it the converse would also apply? Which is that given this mix [of results] you can’t foreclose that there is an effect at U.S. drinking levels?” Savitz conceded this was true.


Judge Chen asked, given Savitz’s response and the NTP’s findings, if it makes sense to assume that there is a concern about current drinking water levels. Chen also asked Savitz if he took issue with NTP’s conclusion that there is an association between fluoride exposure and lowered IQ at 1.5 mg/L - just over two times current fluoridation levels. Savitz said he had no reason to challenge it, but he hadn’t corroborated it.


Savitz said another flaw was that the NTP used high-quality ecological studies - studies of endemic fluoride in other countries - as some evidence to show the effects of fluoride and that those could be confounded by other variables. Chen pointed out that the studies would have controlled for that issue. Savitz conceded they did.


On cross-examination, Connett also pointed out that in Savitz’s own work on arsenic in China, his team studied endemic arsenic at high concentrations to show evidence for arsenic’s toxic effects. They also used that data to consider toxic exposure levels in the U.S., using the same methods NTP scientists and other researchers were using endemic fluoride data, which Savitz criticized.


Connett also asked Savitz if he believed his own statements on uncertainty by quoting from Savitz’s textbook, “Interpreting Epidemiological Evidence: Connecting Research to Applications.” Savitz wrote in the book that “to claim we have insufficient evidence does not resolve the problem for those who make public health decisions, because inaction is an action.”


Throughout his testimony, Savitz maintained there was no strong evidence for the neurotoxic effects of fluoride exposure at “low levels,” which extended up to 2 mg/L. On cross-examination, Connett presented him with data from the NTP report and also from at least one key study showing this link. Savitz conceded he hadn’t read those studies. In fact, in addition to the NTP report, he said he had read only about 10 studies on fluoride and neurotoxicity. EPA’s risk analyst Dr. Stanley Barone took the stand again as the final in-person witness in nine days of testimony at the Phillip Burton Federal Courthouse in San Francisco. FAN attorneys called Dr. Barone earlier to comment on the EPA’s risk analysis methodology even though he’s an expert witness for the EPA. The EPA called him back to testify to the quality of the evidence on fluoride and IQ for a hazard assessment.


Dr. Barone admitted in his testimony that fluoride is neurotoxic at relatively low levels and that EPA’s key expert on fluoride’s neurotoxicity, David Savitz, conceded flaws in his own study as our landmark fluoride trial drew to a close. Fluoride causes “neurotoxic harm,” and does so at relatively low levels, Barone admitted under cross-examination.


Barone said there simply isn’t enough data available for EPA to implement its risk assessment process for fluoride. Pharmacokinetic modeling that predicts how a chemical will be absorbed and metabolized by the body, hasn’t yet been done, he said. But on cross-examination, Attorney Michael Connett forced Barone to concede several of the FAN’s key points.


“You do not dispute that fluoride is capable of causing neurodevelopment harm, correct?” Connett asked. “I do not,” Barone said, adding that he said that in his deposition.


“You agree that the current evidence is suggestive that low-dose fluoride causes neurodevelopmental effects? Correct?” Connett asked. Barone said the “hazard ID” - the level at which a toxin causes effects - “is probably in the suggestive range but is highly uncertain.”
“You agree that fluoride is associated with neurotoxic effects at water fluoride levels exceeding two parts per million?” Connett asked. After first evading the question, Barone conceded.


Connett asked if Barone agreed there should be a “benchmark margin of uncertainty” of 10 for fluoride neurotoxicity. That means the lowest allowable human exposure level should be at least 10 times the hazard level, which Barone conceded may be approximately 2 parts per million. Barone said that is generally true for toxic chemicals under TSCA.


Water fluoridation levels in the U.S. are currently 0.7 parts per million, also referred to as milligrams per liter (mg/L), which would place them well above the allowable level if they were regulated through TSCA’s norms.


Barone also conceded that the NTP’s report linking fluoride to neurotoxicity at 1.5 mg/L is a rigorous, high-quality review and that the NTP is one of the world leaders in doing such reviews.


“Do you feel comfortable as a risk assessor,” Connett asked, “exposing pregnant women to a level of fluoride that is so high that the kidney is oversaturated?” Barone avoided answering, commenting instead on other foods containing fluoride.


Connett asked a second time, “Are you comfortable then with a pregnant woman having so much fluoride in her circulating system that their kidney has lost the ability to efficiently process it?”


EPA lawyers objected to the question as “vague and argumentative” but Chen overruled.


Barone then sat in silence for several seconds before responding, “Again, putting this in context, my comfort level I don’t think is germane.”

Dr. Savitz

Connett then turned to the question of the “data gap” or “uncertainty” that Barone and other EPA experts have argued is the basis for not requiring the agency to regulate fluoride.


Connett asked Barone if he agreed that uncertainty about the threshold level at which a chemical causes harm is not a basis for deciding not to do a risk assessment - the process that would likely lead to chemical regulation. Barone agreed but said the weight of the evidence was key. Connett also asked him if he personally agreed that the EPA should “use health protective assumptions” (i.e. an uncertainty factor or 10) when data is lacking. He said he did.


Chen intervened to ask Barone why the EPA couldn’t do its risk assessment with the given information, using a “lowest observed effect level,” or LOEL. “I mean here we have a phenomenon where I think everybody agrees, as you put it, something’s going on,” Chen said, adding:

“And knowing that the EPA is to use health-protective assumptions when the information is lacking, why can’t one approach it from the low-level approach? We seem to know that there’s some level in which something’s going on. There’s adverse effects. We may debate where it is, but wouldn’t it be proper to use even a conservative estimate of LOEL?”

Barone insisted, as he did in earlier testimony, that the data are unclear. But he also conceded the EPA does often use the LOEL in risk assessment. Throughout Barone’s testimony, Connett drew concessions from Barone through “impeachment” — meaning Barone gave responses under cross-examination that contradicted statements he made in his earlier deposition. Connett read from Barone’s deposition testimony to demonstrate he was misrepresenting his responses.


To wrap up the trial and move forward with closing arguments, Judge Chen privately reviewed the recorded deposition of Jesús Ibarluzea, Ph.D., EPA’s final witness.


Dr. Ibarluzea is the author of the “Spanish study” that found fluoride increased IQ in boys by an implausible 15 points. 15 IQ points is enough to turn an average person into a genius, which no chemical has ever been found to do, calling the findings of his study into serious question.


Dr. Ibarluzea pulled out of testifying publicly in the trial after his study was scrutinized by plaintiffs for its ridiculously unbelievable findings.

Dr. Ibarluzea

At the close of the expert testimony, a scheduling change occurred. The Judge ordered that closing statements from both FAN and EPA now take place with a one-week delay, setting a February 20, 2024, closing date. The judge wanted time to watch deposition videos, look over evidence, and prepare a series of key questions for attorneys.

Closing Arguments

On February 20, 2024, rather than delivering summary closing arguments, attorneys for FAN and EPA responded for nearly three hours to the Judge’s detailed questions on technical aspects of the link between low-level fluoride exposure and lower IQ scores in children. The two sides also debated the role of uncertainty in risk assessment.


During the trial, top scientific experts who advised the EPA on understanding and setting hazard levels for other major environmental toxins and who conducted gold-standard “cohort” studies on the link between fluoride and low IQ in children testified for FAN.


They explained the NTP’s findings and presented evidence from their own research showing neurotoxic risks - particularly to pregnant women, formula-fed infants and children- posed by water fluoridation.


EPA witnesses conceded fluoride does have neurotoxic effects at relatively low levels but countered that the risk assessment process under TSCA is highly complex and there is too much uncertainty in the data on fluoride’s toxicity at current levels of water fluoridation to do a proper risk assessment and regulate the chemical.


It is now up to Judge Chen to decide if the EPA should be required to create a rule banning water fluoridation in the U.S. “Because the regulatory agencies have failed to do their job for decades,” plaintiffs’ attorney Michael Connett told Brenda Baletti of The Defender, “the court is now in the position of having to do it for them.”


“It’s not a job the court takes lightly,” he said. “It’s not a job the court wanted to do, but I think it’s a job the court is prepared to do.”

The Judgement

As of May 2024, a judgment from the court in the TSCA Fluoride Lawsuit has yet to be rendered. Judge Chen’s decision could affect more than 200 million Americans who drink fluoridated water.

TSCA Lawsuit Timeline

Thanks to Derrick Broze of the Conscious Resistance and Brenda Baletti of Children’s Health Defense for their contributions to this detailed overview of the TSCA fluoride lawsuit.