Portland fluoridation clash echoes in unprecedented trial
Update: This article has been updated to include court proceedings on June 17.
In a case that could have implications for the drinking water of one out of four Oregonians, a federal judge has urged the U.S. Environmental Protection Agency to reconsider the safety of fluoridation in light of recent studies associating the practice with lowered IQ in children.
The judge's comments on June 17 came at the close of a live-streamed federal trial in San Francisco.
Nobody in the case is questioning the safety of using fluoridated toothpaste. Nor did plaintiffs argue in court that fluoridated water is a threat to adults who drink it.
Rather, the case hinges almost exclusively on whether consumption of fluoridated water by a pregnant person is associated with impairment to the developing brain of their child.
The American Dental Association has attacked the new science as inconclusive and potentially biased. Similarly, EPA contends the latest science does not prove that fluoridation causes harm to developing brains.
The debate is well known to Oregonians. In May 2013 Portland voters resoundingly voted down fluoridation, rejecting the safety assurances of the federal Centers for Disease Control and Prevention, state public health experts and the American Dental Association. About 27% of Oregonians, including those living in portions of Washington County, are served by fluoridated water.
In contrast, about three-quarters of the rest of the country, some 200 million people, drink fluoridated water. About two million babies are born in fluoridated communities each year.
The recent trial was sparked by a lawsuit filed against the U.S. EPA by Food and Water Watch, the Fluoride Action Network and other groups. The suit appealed the EPA's earlier denial of a 2016 petition to block fluoridation.
Over seven days, lawyers remotely grilled each other's expert witnesses as well as EPA water safety experts.
Testifying for plaintiffs were scientists who, since 2017, have published a series of long-term studies of human exposure in Canada and Mexico in well-regarded, peer-reviewed journals. The studies cross-referenced maternal urinary testing to subsequent IQ tests, and connected even the low levels found in fluoridated water to effects that included attention-deficit hyperactivity disorder as well as an average loss of several points of IQ in children — roughly equivalent to the impact of low levels of lead. The studies' designs were approved by the U.S. National Institutes of Health, which also funded them
In court, EPA witnesses conceded that fluoride at high enough levels can harm developing brains, before children develop a protective "blood-brain barrier" at about the age of six months.
But EPA's outside experts argued that the studies' findings were contradictory, potentially biased, and did not constitute sufficient proof that fluoridation levels were harmful. For instance, one study found primarily boys' IQ was affected, and the other did not.
The EPA also said still other studies do not indicate that water fluoridation harms developing brains.
Judge faults EPA
Following closing arguments, District Judge Edward M. Chen cited testimony from one of the EPA's top fluoride experts, Joyce Donohue, who said the studies cited by plaintiffs were well-designed and should be part of an EPA reassessment of fluoride's safety.
"This is coming from someone who knows her stuff," Chen said.
The judge said he agreed with plaintiffs that the federal government had applied an improper standard to deny the plaintiff's 2016 petition seeking to ban fluoridation. The EPA had required that studies show clear proof that harm is caused by fluoridation levels, as opposed to the lower "unreasonable risk" standard it had used with other toxins.
"I don't think it's much disputed that fluoride can be a hazard," Chen said, discussing earlier testimony. "At some level it's a hazard, a neurological hazard ... The question ultimately is this one: At the community water fluoridation levels ... and given the way it's used and exposed and consumed by bottle ... does it present an unreasonable risk?"
EPA should meet with the plaintiffs and figure out a streamlined way to revisit its earlier decision, the judge said, adding that the new studies "raise serious questions."
The review could include several other studies underway of fluoride and potential neurotoxic effects, including one by the U.S. government's National Toxicology Program, Chen said.
The judge said EPA should expedite its review, and he was prepared to rule if the two sides did not reach an acceptable compromise. The lawyers will report back to him in an Aug. 6 hearing. He said the new review should not lead to unreasonable delay.
"It's a matter of months, not years," Chen said.
You count on us to stay informed and we depend on you to fund our efforts. Quality local journalism takes time and money. Please support us to protect the future of community journalism.