One month after this video presentation was given at the annual scientific conference of the International Society for Environmental Epidemiology (ISEE), the court issued its decision.  The court essentially agreed with the evidence and interpretations made in this video and ruled in favor of the citizen groups and against the EPA. The court issued a detailed 80-page decision that concluded, in part:

“The Court finds that fluoridation of water at 0.7 milligrams per liter (“mg/L”) – the level presently considered “optimal” in the United States – poses an unreasonable risk of reduced IQ in children…the Court finds there is an unreasonable risk of such injury, a risk sufficient to require the EPA to engage with a regulatory response.”

“In all, there is substantial and scientifically credible evidence establishing that fluoride poses a risk to human health; it is associated with a reduction in the IQ of children and is hazardous at dosages that are far too close to fluoride levels in the drinking water of the United States…Reduced IQ poses serious harm. Studies have linked IQ decrements of even one or two points to, e.g., reduced educational attainment, employment status, productivity, and earned wages.”

Additional details about the court’s ruling, including the full text of the ruling, are available here:

The video presentation describes the key scientific evidence and issues in the lawsuit, and the court agreed with the citizen group Plaintiffs on all of the key evidence, issues, and interpretations of the TSCA law. Additional quotes from the decision highlight some of these points that persuaded the court that fluoridation at a concentration of 0.7 milligram per liter of water poses an unacceptably high risk of reduced IQ in children and the EPA must develop regulations to eliminate that risk:

“The pooled benchmark dose analysis concluded that a 1-point drop in IQ of a child is to be expected for each 0.28 mg/L of fluoride in a pregnant mother’s urine. This is highly concerning, because maternal urinary fluoride levels for pregnant mothers in the United States range from 0.8 mg/L at the median and 1.89 mg/L depending upon the degree of exposure. 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.” (p. 5)

“There is significant certainty in the data set regarding the association between fluoride and reduced IQ. Namely, there is a robust body of evidence finding a statistically significant adverse association between fluoride and IQ. A large majority of the 72 epidemiological studies assessed by the NTP Monograph observed this relationship including all but one of the 19 high-quality studies … and literature published after the NTP Monograph cutoff date observed the same relationship … – and countervailing evidence, for various reasons described previously, are of little impact on this repeated, and consistently observed association between fluoride and reduced IQ …. Moreover, complete consistency amongst studies is not expected. … Notably, notwithstanding inherent difficulties in observing this association at lower exposure levels, studies assessing such levels still observed a statistically significant relationship between fluoride and reduced IQ.” (p. 78)

Following the release of the court ruling there was widespread news coverage, much of it accurate, but also frequently including false claims that clear evidence of IQ loss was only found in studies with water fluoride concentrations of 1.5 milligrams per liter (mg/L) or higher.  Furthermore, there were claims in press releases from fluoridation advocates and news stories that such concentrations were so much higher than 0.7 mg/L that they were irrelevant to community water fluoridation. Some claims went even further and falsely said there was no evidence that artificial fluoridation at 0.7 mg/L posed any risk at all.

The full 80-page ruling demonstrates the court thoroughly discussed and weighed a large body of scientific evidence and found compelling support for its conclusion that lowered IQ was not just happening at 1.5 mg/L, but almost certainly at 0.7 mg/L too. The court ruling found that artificial fluoridation poses more than just a speculative risk but is close to certain for at least some segment of the population with fluoridated water.

During the trial, Defendant EPA tried to use a single study from the Basque region of Spain that found a huge increase in IQ as a centerpiece of its argument that there was too much uncertainty to conclude fluoridated water was neurotoxic. Extensive testimony was obtained from both sides about this study, including almost two hours of deposition from the lead author of the Basque study, Jesus Ibarluzea. Tellingly, despite originally intended by EPA to be a star witness, Ibarluzea withdrew from the case before the trial, which may have further reduced the credibility of his study in the court’s eyes.

The court ruling addressed the Ibarluzea study in depth and agreed it had many of the problems that had been pointed out during trial testimony. The court’s ruling said:

“The reliability of Ibarluzea (2021) is questionable in several respects: …” [followed by 2 pages of detailed reasons why the court considered the Ibarluzea study of questionable reliability; Court ruling, pp. 27-29]

“… as also explained previously, particular characteristics of these studies finding null outcomes render them less probative here….  Ibarluzea (2021) found an unrealistic 15-point IQ benefit, included unexplained and implausible results regarding creatinine adjustments, and failed to control for seafood” [Court ruling, p. 39]

Some of the problems that brought the reliability of Ibarluea’s study into question are explained in a presentation video that Neurath prepared for the ISEE 2024 Conference but did not have time to present.  The video is now available to help those wishing to understand why the court agreed that the Ibarluzea study deserved little weight:

Chris Neurath, FAN Science Research Director