Briefing Document: Findings on Fluoride and IQ

This briefing document summarizes the key findings of the court case Food & Water Watch, Inc., et al. v. United States Environmental Protection Agency, et al. The plaintiffs, a group of advocacy organizations and individuals, argued that community water fluoridation at the level of 0.7 mg/L, the recommended level in the United States, posed an unreasonable risk to human health, specifically a reduction in IQ in children. The court found in favor of the plaintiffs, ordering the EPA to initiate rulemaking under the Toxic Substances Control Act (TSCA).

Here's a breakdown of the court's reasoning:

• Hazard Identification: The court found, based on a review of the scientific literature, that exposure to fluoride is associated with reduced IQ in children, particularly in boys. This finding was primarily based on the NTP Monograph on the State of the Science Concerning Fluoride Exposure and Neurodevelopmental and Cognitive Health Effects: A Systematic Review, which analyzed 72 human studies on the topic.
• Weight of the Scientific Evidence: While acknowledging that not all studies have found an association between fluoride and reduced IQ, the court determined that the weight of the evidence, particularly the NTP Monograph, was sufficient to proceed to a dose-response assessment.
• Dose-Response Assessment: The court identified two potential points of departure (PODs), which represent the level at which fluoride becomes hazardous:

0.28 mg/L maternal urinary fluoride (BMCL): This POD was derived from a pooled analysis of birth cohorts by Dr. Grandjean, which found that an increase of 0.28 mg/L of fluoride in maternal urine was associated with a 1-point drop in a child's IQ.

4 mg/L water fluoride (LOAEL): As a more conservative alternative, the court considered a LOAEL of 4 mg/L based on the NTP Meta-analysis.

• Exposure Assessment: The court determined that maternal urinary fluoride was an appropriate metric for assessing fluoride exposure, as it reflects total fluoride intake. Data from the Till (2018) and Malin (2023) studies showed median and 95th percentile maternal urinary fluoride levels exceeding the identified PODs, indicating a risk.
• Risk Characterization: The court calculated the actual margin of exposure (MOE) by comparing the exposure level with the PODs. In all cases, the actual MOE was less than the benchmark MOE (10 for the BMCLs, 100 for the LOAEL), indicating a risk.
• Risk Determination: Considering the severity of the hazard (reduced IQ), the continuous exposure of a large population, and the susceptibility of pregnant women and infants, the court concluded that the risk of reduced IQ from water fluoridation at 0.7 mg/L is unreasonable.

Conclusion:

The court's decision in Food & Water Watch, Inc., et al. v. United States Environmental Protection Agency, et al. highlights concerns about the potential neurotoxic effects of fluoride, particularly at levels currently used in community water fluoridation programs. While the court acknowledged some uncertainties in the data, it ultimately found the weight of the evidence compelling enough to warrant regulatory action by the EPA.

Court Document

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