LAW360. EXCERPT. A Brown University epidemiologist testified Friday on behalf of the U.S. Environmental Protection Agency in a bench trial over fluoride’s risks Friday that there are data “gaps” in studies linking fluoride exposure to lower IQ, while acknowledging under cross-examination that he hadn’t reviewed studies assessing the effects of high-dose fluoride exposure.
The EPA called Savitz as its first witness on Wednesday, and he testified that he recently participated in a Canadian health panel reviewing the latest scientific studies on the potential effects of fluoride exposure.
Savitz testified that there’s too much uncertainty in the scientific data on the neurocognitive impacts of fluoride exposure from drinking water, which typically has 0.7 mg/L of fluoride, and it would be premature to regulate fluoridated water based on its potential neurotoxicity. Before trial recessed Wednesday, Savitz said his panel recommended that Canadian water regulators instead focus on moderate dental fluorosis — a condition resulting from taking in too much fluoride as a kid — that can occur with fluoride exposure above 1.56 mg/L.
… Savitz also acknowledged that there wasn’t a single problem definitively showing the studies’ conclusions were wrong. Instead, he said, there were a series of issues, including various methods of fluoride testing and population demographics, that “might seem to be modest initially, but cumulatively … it’s not making its case well.”
“They were not being as direct as we would want them to be,” he said of the NTP’s monograph.
… Although the professor acknowledged the fluoride IQ studies do appear to “follow the pattern” that NTP researchers suggest, showing a link between IQ drops and levels of fluoride exposure above 1.5 mg/L, Savitz cautioned against drawing strong inferences from them.
“I’m not saying they were completely off base — not at all,” he said. “They probably got it right, but there are some real concerns about the description of the process and the details.”
… Savitz’s cross-examination began with the plaintiffs’ counsel reading the professor quotes from his own textbook stating that the precise “causal nature of any given effect is almost never known” in epidemiological studies. The counsel also tried to get Savitz to concede that at least one other member on his panel had a conflict of interest in assessing the risks of fluoride, but Savitz denied knowing about the other panelist’s purported conflicts, and the judge sustained objections to further questioning on the issue.
… Savitz also acknowledged that confounding of data “probably could not” explain the relationship between fluoride and IQ, and he agreed that he never reviewed fluoride studies involving doses of fluoride of 1.5 mg/L or higher. Before trial recessed for the day, Savitz also repeatedly acknowledged that he’s not a risk assessor, and that he doesn’t know how the EPA evaluates “risk” under TSCA…
Original article online at https://www.law360.com/articles/1796315/brown-prof-testifies-that-fluoride-iq-studies-have-gaps
Print 
PDF