On day two (Thursday, February 1st), the court heard from two more expert witnesses for the plaintiffs, Dr. Bruce Lanphear and Dr. Phillipe Grandjean.

Bruce Lanphear, MD, MPH

Attorneys for the Fluoride Action Network (FAN) called their second expert witness for the trial and their first for day two. Bruce Lanphear, MD, MPH, has studied the impact of toxic chemicals, including lead and pesticides, on children’s brain development for over 20 years. He works as an investigator at BC Children’s Hospital and as a professor of health sciences at Simon Fraser University. His research focuses on fetal and childhood exposures to environmental neurotoxins.

He testified that his research has been almost exclusively funded by federal agencies, including the U.S. Environmental Protection Agency (EPA), the Centers for Disease Control and Prevention (CDC), and Health Canada. Dr. Lanphear has also served on multiple scientific advisory boards for the EPA and the American Academy of Pediatrics, and has earned various awards for his work, including the Research Integrity Award from the International Society for Environmental Epidemiology and the Advocacy Award from the Academic Pediatric Association.

He’s well-known in the environmental science community for authoring seminal research on the neurotoxicity of low levels of lead. He testified that his blood lead research, funded by the National Institutes of Health (NIH), was cited by the EPA as the principle study upon which the agency based the 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, including (Green et al., 2019), which was published in JAMA Pediatrics. He testified that this study underwent multiple peer reviews, including by a team of independent subject matter experts who separately verified the findings that maternal exposures to fluoride, at the levels experienced in Canadian fluoridated communities, were linked to a reduction in IQ for the male children. He said that the dose-response relationship was linear, meaning that the effect occurred with any level of exposure and increased as the exposure to fluoride increased.

Lanphear also stated that out of the 350+ studies he’s published, (Green, 2019) 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.”

There was then discussion of another study he co-authored (Till et al., 2020), 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 fluorideexposures 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.

The discussion then focused on fluoride’s effects on the thyroid and how this could increase hypothyroidism rates for 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, including (Hall et al., 2023 and Goodman et al., 2022). He pointed out that in the 2006 National Research Council report, they recognized that fluoride was a thyroid disruptor. He also noted that iodine deficiency has only been increasing in the United States.

Attorney for the plaintiffs, 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 (Till et al., 2018) measuring the maternal urinary fluorideconcentrations of pregnant women. He testified that the average woman living in a fluoridated community had fluoridelevels in their urine that were twice as high as the 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 day two of the trial. Click below to watch:

Phillipe Grandjean, MD, DSMc

The third expert witness called by the plaintiffs since the start of the trial, and the second witness called on day two 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.

He testified that he has been given grants and/or contracts to advise the EPA, the National Institutes of Health, the U.S. Food and Drug Administration, the World Health Organization, and numerous other government bodies for over 25 years. He 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.

He 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. He’s seen similar results recently to his groundbreaking work on perfluorinated alkylate substances (PFAs). He explained that he recently collaborated with the EPA on finding a benchmark dose for PFAs, PFOs, etc. Grandjean said, “I must admit, they [the EPA] used my study.”

Since the 1980s, Dr. Grandjean has been studying the effects of fluoride. In regard to fluoridation, Dr. Grandjean’s name came into prominence when he published a meta-analysis of 27 fluoride-IQ studies, which found–even though they were conducted in many different geographical areas by different research teams over a period of about 20 years—a remarkably consistent result (Choi et al., 2012). Of these 27 studies, 26 found a lowering of IQ in the children with higher fluorideexposure.

Since his work in 2012, Dr. Grandjean has authored or co-authored additional studies and reviews on fluoride’s neurotoxicity, including (Choi et al., 2014), his updated review on fluoride neurotoxicity (Grandjean, 2019) and the first benchmark dose analysis on fetal fluoride exposure (Grandjean et al., 2021), which found that a maternal urine fluorideconcentration of 0.2 mg/L, which studies show is exceeded 4 to 5 times in pregnant women living in fluoridatedcommunities (Uyghurturk et al., 2020; Till et al., 2018), was enough to lower IQ by 1 point.

Dr. Grandjean testified that he used the exact same methodology for a benchmark dose analysis on PFOAs that the EPA used to regulate the chemical and that the EPA uses as an example of the “best practice” for benchmark dose analyses.

While discussing his life’s work, Dr. Grandjean really summed up the importance of this trial by describing how the developing brain is “uniquely vulnerable,” with the most vulnerable populations to neurotoxins being pregnant women and newborns. He continued, “You only get one chance to develop a brain. Once it’s harmed, there’s nothing you can do.”

Grandjean confirmed that the fluoride that the mother is absorbing will pass into the child’s brain. He also agreed that the 2006 NRC report found that fluoride could cause toxic changes in the brains of animals.

Attorney Connett showed a quote from EPA scientist Kristina Thayer, who provided testimony in the first phase of the trial. She 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 about the EPA’s opening statement, in which they claimed that these Chinese studies (Choi et al., 2012) were looking only at very high levels of fluoride exposure. Grandjean said that this was not the case, saying that even at lower levels there was evidence of cognitive impacts from fluoride and confirming outright that he felt neurotoxicity was definitely a hazard of fluoride exposure.

Connett asks Grandjean about the National Toxicology Program’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 fluoridatedcommunities.

As the day came to an end, he 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.” He continued, agreeing with the 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.”

Before the court adjourned, Connett asked the judge to make the EPA reveal who their rebuttal witness would be. The judge agreed, and the EPA said it would be Richard Woychik, Ph.D., Director of the National Institute of Environmental Health Sciences (NIEHS).


Stuart Cooper
Executive Director
Fluoride Action Network