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    ‘Here We Go Again’: Kentucky Residents Face More Destruction and Anxiety From Storms

    The flood damage over the weekend was not as catastrophic as some previous climate disasters in the state. But the rains still brought widespread havoc, and painful reminders of trauma.As the rains began to drench Eastern Kentucky this weekend, Mimi Pickering looked anxiously out her window in the town of Whitesburg as the North Fork Kentucky River kept rising, and rising, and rising.Would it once again swallow the bridge that leads to the historic Main Street? And would the media and arts education center where she is a board member be damaged, as it was a few years before?“It just looked so much like the 2022 flood — it felt just like, ‘Here we go again, this is unbelievable,’” Ms. Pickering, a filmmaker, said. “It’s been traumatic for people when it rains so heavily — it just adds to that PTSD.”By Sunday, a clearer picture had begun to emerge of the destruction caused by the storms: At least nine people dead throughout the state, with the death toll expected to rise. Nearly 40,000 people without power. More than 1,000 rescues. At least 300 road closures of state and federal roads. Two wastewater systems out of service, including one that was underwater.And more grim news was likely, Gov. Andy Beshear of Kentucky said during a news conference on Sunday, warning that a snowstorm was expected in the next few days that could dump as much as six inches. He urged Kentuckians to stay home and allow emergency boats, vehicles and workers to reach people in need.“This is one of the most serious weather events that we’ve dealt with in at least a decade,” he said.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe. More

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    ‘Ridiculous blunder’: Trump wades into California’s water wars – and strikes some of his strongest supporters

    Under orders from Donald Trump, billions of gallons of irrigation water were laid waste in California’s thirsty agricultural hub this month, a move that left water experts shocked and local officials scrambling.The water, stored in two reservoirs operated by the army corps of engineers, is a vital source for many farms and ranches in the state’s sprawling and productive San Joaquin valley during the driest times of the year. It will be especially important in the coming months as the region braces for another brutally hot summer with sparse supplies.The reservoirs are also among the few the US president can control directly.Staged to give weight to Trump’s widely debunked claims that flows could have helped Los Angeles during last month’s devastating firestorm and to show that he holds some power over California’s water, he ordered the army corps to flood the channels. Less than an hour of notice was reportedly given to water authorities down-river who rushed to prepare for the unexpected release, which threatened to inundate nearby communities.The move is just the latest in a series of misinformed attempts Trump has made to wade into California’s water wars, adding new challenges and conflicts over the state’s essential and increasingly scarce water resources. But in what now appears to be just a political stunt, Trump has struck some of his strongest supporters. Many counties across California’s rural Central valley – home to much of its roughly $59bn agricultural industry – backed Trump in the last election, forming a red strip at the heart of the blue state.“It is almost mind-boggling that this has happened,” said Thomas Holyoke, a professor of political science and water expert at California State University, Fresno, calling the act a “ridiculous blunder”.Experts, who were left scratching their heads in the aftermath, have found no justification for the order. The reservoirs were not at risk of overflowing and irrigation is not necessary during the wetter winter months. These releases also did not support threatened ecosystems such as those in the Sacramento-San Joaquin delta, where contentious debates continue about flows and diversions.Some have suggested the flows will help bolster groundwater stores, “but a lot of that water will end up evaporating,” said Holyoke. “It’s just going to be water lost – and they know it.”‘Purely a stunt’Governed by agreements between an array of stakeholders and close coordination between federal and local officials, releases from these reservoirs are typically well-planned. Lake Kaweah and Lake Success, the two reservoirs in Tulare county, are part of a sprawling network of channels that do not flow to the ocean or connect to the aqueduct serving the southern part of the state.The water held within them is also largely spoken for. Its distribution isn’t often contentious.But Trump, it seems, saw it differently.“Everybody should be happy about this long fought Victory!” he said in a post on Truth Social the day the release was ordered, boasting that he opened a flow for 5.2bn gallons of water alongside a photo of a nondescript waterway.Acting quickly, local authorities were able to convince federal officials to bring that total down to 2bn, which was released over three days.View image in fullscreenBut Trump’s rhetoric around the issue hasn’t shifted. He has made several false statements about water in California and his ability to direct it including claims that he sent the US military to turn on the water in the aftermath of the deadly fires, his clear misunderstanding about where water supplies originate from and distribute to, and his allusion to a simple valve that can be turned to control water supply.He posted again thanking the army corps of engineers “for their LOVE of our Country, and SPEED in getting this Emergency DONE! [sic]” saying that water was “heading to farmers throughout the State, and to Los Angeles”, even as experts repeatedly debunked this claim.“Those releases had absolutely zero to do with anything to do in Los Angeles,” said Gregory Pierce, a water policy expert and the director of the UCLA Water Resources Group, adding that this also did not benefit anyone in the central valley. “This was a stunt purely so Trump could say that he did something and released the water.”Few have been willing to admonish the administration for the move. Support for Trump and hopes that he will aid agriculture with its water woes is still strong in this region.“I have a conservative mindset. I encourage the trigger-pulling attitude, like: ‘Hey, let’s just get stuff done,’” Zack Stuller, a farmer and president of the Tulare county farm bureau told Politico, admitting that the reservoir release was a little nerve-wracking.The bureau declined to comment to the Guardian, but sent a combined statement from the four water management associations and districts, which attempted to make sense of the puzzling and dangerous release. In it, they said there would be “continued close coordination with the Administration and the Army Corp of Engineers”.skip past newsletter promotionafter newsletter promotionSome locals who said they were deeply concerned about the act and its outcome said they were afraid to speak out because their businesses might be targeted by supporters of the administration.While Trump continues to frame the action as evidence that he has taken power over California water, he isn’t able to control much water policy in the state, according to Pierce.“The federal government of course matters for water in California, but not that much,” he said, adding that’s why Trump ordered releases where he was able to, even if they weren’t connected to the overall problem he was claiming to address. The federal government does play a role in funding big projects but “California’s been left on an island with respect to federal support for quite some time,” he said.Trump has tried to exert more control through funding, especially now that the state is depending on the federal government for aid in the aftermath of the Los Angeles wildfires, now considered one of the most costly natural disasters in history with damage estimates climbing above $250bn.View image in fullscreenTrump has cast California’s governor Gavin Newsom as his opponent on the issue, but when it comes to water, and more specifically boosting supplies of it for cities and agriculture, the two might already be on the same page.The state recently issued a fact-check on Trump’s claims, which criticized him for spreading misinformation, but highlighted how supplies have increased since Trump’s first term.Environmental advocates have long criticized the Delta Conveyance, a controversial infrastructure project championed by Newsom that would reroute more water to the south, which could get even more momentum under a Trump presidency.“The governor is actually aligned with Trump on this and I think Trump has only recently figured that out,” Pierce said. “The cards are certainly stacking up that that’s going to be pushed forward.”That doesn’t mean that Trump’s misleading rhetoric won’t leave a mess.“President Trump comes blundering into this complex situation with no understanding at all or no effort at understanding how it works,” said Holyoke.“California is trying to strike a delicate balance,” he added, detailing the challenging and layered issues that come with distributing essential resources to residents, the agricultural industry, and declining ecosystems as the world warms and supplies run short.“Farmers in the valley are hurting from water cutbacks, there is no question about that,” Holyoke said. “The answer isn’t to toss all the laws and court orders aside and throw lots of water at farmers. We simply need to find inventive ways to make the best use of the water that we have.” More

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    Spillover in Lake Berryessa Reservoir Gushes for First Time Since 2019

    For the first time in six years, water is gushing through a unique spillway in Lake Berryessa, just north of San Francisco.Footage provided to The New York Times showed Lake Berryessa’s spillway overflowed with water.Jay Cuetara, Solano County WaterBack-to-back atmospheric rivers have dumped buckets of rain across Northern California, filling its rivers to the brim and beyond. The Russian River spilled over its banks in Sonoma County, and in the far reaches of the state, Lake Shasta, a key marker of the state’s overall water levels, has nearly filled up.And just east of Napa Valley, a rare not-fully-natural phenomenon was observed for the first time since 2019: Water began gushing, furiously, through a spillway in Lake Berryessa.The eye-catching event has happened only three other times in the past 20 years, and it has drawn curiosity seekers to the man-made reservoir, 70 miles northeast of San Francisco.“People were taking pictures and videos and just standing in awe,” said Peter Kilkus, the editor of the Lake Berryessa News, who was there Wednesday morning with about two dozen other people.The 72-foot-wide spillway, called a morning glory because its shape mimics the flower, is a unique funnel-shaped cement pipe that sits within the reservoir. (Locals call it the glory hole.)The mechanism is a type of drainage system with water pouring down the pipe and into Putah Creek on the other side of Monticello Dam. The spillway is among a few with that shape in the country; there’s also one at Pleasant Hill Lake in Perrysville, Ohio. More

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    U.S. Coast Guard Suspends Search for 5 People Missing in Alaska Waters

    The Coast Guard received a mayday call from a fishing boat on Sunday just after midnight. Search crews looked for its passengers for almost 24 hours.The U.S. Coast Guard said on Monday that it had suspended a search for five people who made a mayday call from a fishing boat off Alaska just after midnight on Sunday.The Coast Guard spent almost a full day covering over 100 square nautical miles searching for the 50-foot fishing vessel, which was called Wind Walker, and its crew, according to a news release from the military branch. Search crews reported finding seven cold-water immersion suits and two strobe lights but no remnants of the boat or anyone onboard. The boat reportedly capsized near Couverden Point, Alaska, in the Icy Strait, according to the Coast Guard.The crew said they were evacuating onto an emergency life raft during their mayday call, according to Travis Magee, assistant public affairs officer for the Coast Guard. Emergency marine responders who answered the call attempted to get more information from the crew but got no response, Mr. Magee said.A nearby ferry vessel, AMHS Hubbard, heard the emergency call over a broadcast and arrived first to help. A helicopter and a boat were also deployed from the Coast Guard.“We stand in sorrow and solidarity with the friends and family of the people we were not able to find over the past 24 hours,” Chief Warrant Officer James Koon, a search and rescue mission coordinator at Coast Guard Sector Southeast Alaska, said in a statement.There were six-foot seas, heavy snow and winds of up to 60 miles per hour when the boat was lost, officials said. Alaska was under winter weather warnings over the weekend, and some have been extended through Tuesday, according to the National Weather Service.The search was called off for now “pending the development of new information,” the Coast Guard said in a statement. The names of those missing have not been released. More

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    ‘The science of fluoride is starting to evolve’: behind the risks and benefits of the mineral

    A national conversation about fluoride’s health benefits exploded this fall after a federal toxicology report, court ruling and independent scientific review all called for updated risk-benefit analysis.Fluoride, a naturally occurring mineral in some regions, has been added to community water supplies since the mid-20th century when studies found exposure dramatically reduced tooth decay.The controversy, heightened by description of the mineral as “industrial waste” by Robert F Kennedy Jr, Donald Trump’s pick to lead the US health department, highlights questions some towns are now wrestling with: should the mineral’s well-established protective effects against tooth decay be prioritized lest Americans, and especially children, be subject to unnecessary pain and shame from an unhealthy smile? Or should the possibility of neurodevelopment effects be prioritized, even as studies continue?“Fluoride is the perfect example of helping people without them even having to do anything,” said Dr Sreenivas Koka, the former dean of the University of Mississippi Medical Center’s school of dentistry. The state is a “dental desert”, where there is only one dentist for every 2,120 residents. “Fluoride in the water – all you have to do is drink water and you’ll get the benefit.”Fluoride is added to about 72% of community water supplies in the US, according to the Centers for Disease Control and Prevention (CDC). The CDC again endorsed the practice in a scientific statement this May, saying it found no “convincing scientific evidence linking community water fluoridation with any potential adverse health effect or systemic disorder such as an increased risk for cancer, Down syndrome, heart disease, osteoporosis and bone fracture, immune disorders, low intelligence, renal disorders, Alzheimer disease, or allergic reactions”.Still, controversy over water fluoridation recently made headlines after two high-profile reports and a federal court ruling. The US National Toxicology Program set off a firestorm in August when it published a systematic review that found with “moderate confidence” that children exposed to fluoride levels twice those recommended for drinking water (1.5mg per liter versus the recommended 0.7mg per liter) “are consistently associated with lower IQ in children”.Then, in October, a new Cochrane Review lowered the estimated impact of fluoride, citing the widespread use of fluoride in toothpaste beginning in 1975.“Studies conducted in 1975 or earlier showed a clear and important effect on prevention of tooth decay in children,” Cochrane Review researchers wrote. “However, due to the increased availability of fluoride in toothpaste since 1975, it is unlikely that we will see this effect in all populations today.”The public debate comes as the National Institutes of Health (NIH), the world’s largest publicly funded research agency, is both a key funder of research advancing society’s understanding of fluoride’s non-dental health effects and an agency squarely in Trump’s crosshairs.The agency is one of the top targets for cuts and restructuring. Paradoxically, that could mean that critics such as Kennedy cut research on fluoride, even as the NIH funds research into potential detriments. The incoming administration has not made proposals on how to improve oral health in the US.Fluoride’s health benefits were investigated in the early 20th century, when a Colorado Springs dentist questioned why town residents had brown, mottled and decay-resistant teeth – now known as fluorosis.It was later found that fluoride naturally occurred at high levels in Colorado Springs, causing the cosmetic defects. Its decay-resistant properties were confirmed in a landmark 1945 study in Grand Rapids, Michigan, which found children in Grand Rapids were 60% less likely to develop dental caries (better known as cavities) with fluoride added to water.By 1999, the CDC hailed water fluoridation as one of public health’s greatest victories, alongside seat belts and vaccination. That view was buttressed by a 2015 Cochrane Review, considered the gold standard, that found fluoridating water at 0.7mg per liter led to a nearly 26% reduction in tooth decay, a figure still cited by the American Dental Association (ADA) and American Academy of Pediatrics (AAP) today.The need for preventive oral health solutions is profound in the US – more than 68 million people lack dental insurance and about one in four adults said in a survey they have avoided the dentist because of cost.In addition, school children lose an estimated average of 34m school hours each year due to unexpected dental visits; 2 million Americans visit the emergency room each year because of tooth pain; half a million travel abroad for cheaper care and one in five American seniors lack a single natural tooth. Lack of dental access is so common in some areas, doctors in prison frequently have patients who have never seen one.“One of the things I routinely ask young people in juvenile jail is: ‘Do you have a doctor? Do you have a dentist?’” said Dr Fred Rottnek, former medical director of St Louis county jails in Missouri and now a professor of community medicine at Saint Louis University School of Medicine. “A lot of them have never reported going to the dentist.”Modern inquiry into fluoride’s non-dental health effects began to pick up pace in 2015, when the National Toxicology Program (NTP) requested a systematic review on fluoride’s impact on neurodevelopment. By 2019, toxicology researcher Bruce Lanphear, of Simon Fraser University in Canada, co-authored a study finding fluoride exposure was associated with decreased IQ, which would later be incorporated into the NTP’s systematic review.“That gives you an indication that the science of fluoride is starting to evolve – it wasn’t set in stone 70 years ago,” he said.Lanphear, and a small group of like-minded toxicology researchers, argue now is the time for us to “pause and have an independent scientific committee look at all this new evidence” as “we have a lot of new science specifically about fluoride and the developing brain,” he said.Critics were buttressed again when a federal court ruled in September that the Environmental Protection Agency (EPA) needed to evaluate fluoride under the Toxic Substances Control Act.But physicians, dentists and mainstream professional associations from the American Dental Association to the American Academy of Pediatrics stand by recommendations for fluoridated water.While some towns step away from fluoride, communities such as Buffalo, New York, are restarting programs.“This is a shame if we don’t take advantage of what we know from the science,” said Koka about the preventive effects of fluoride. “Are there challenges to doing it right? Yes, but should they be so strong they overcome trying at all? That’s a tragedy.”The CDC has also refined guidance about fluoridation in recent years. In 2015, its water fluoridation recommendations went down to 0.7mg per liter of water, from 0.7 to 1.0mg per liter dependent on climate. Later, the CDC issued a 2019 report that advised parents of children younger than two to speak with their dentist about fluoridated toothpaste, and reminded parents of children younger than three to use only a “grain of rice”-sized “smear”.As critics argue that federal agencies’ recommendation lag behind, the US government’s National Institutes of Health (NIH) has become one of the chief funders of research into fluoride’s potential impacts on IQ.“Getting funding from the NIH shows they are interested in this important question,” said Christine Till, an assistant professor at York University in Canada and a co-investigator with Lanphear, whose grant studying tooth dentin and neurodevelopment in Canada was funded by the NIH, but turned down by the Canadian government.Others, such as Ashley Malin, epidemiology professor at University of Florida, and Dana Goin, assistant professor of epidemiology at Columbia University, have also received NIH funding to research fluoride’s non-dental health effects. Malin is studying fluoride’s impact on children’s sleep and Goin is investigating reproductive health effects.“There is a lot of ongoing work in this area, particularly in the US,” said Goin. “Hopefully, the results from these studies will help determine whether EPA drinking water regulations and CDC recommendations for water fluoridation are adequately balancing improvements in dental health from fluoridation versus any potential negative effects.”Goin’s current funding builds on her previous work, which found water fluoridation was not associated with small-for-gestational age or preterm births. She is now exploring whether fluoride is associated with gestational diabetes.Malin added that it’s a sign of “progress” that the studies can be discussed: “Over a decade ago, to even ask the question of whether optimally fluoridated, or the concentration in drinking water, could be impacting neurodevelopment was quite controversial.” More

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    Florida Surgeon General Urges End to Fluoride in Water, Backing RFK Jr.’s Push

    Florida’s surgeon general issued guidance on Friday that called for a halt to adding fluoride to the water supply, backing a similar push by Robert F. Kennedy Jr. — President-elect Donald J. Trump’s pick to lead the Department of Health and Human Services.Dr. Joseph A. Ladapo, who was appointed by Gov. Ron DeSantis, a Republican, cited recent research that highlighted the potential risk of heightened exposure to the chemical — including lower I.Q.s in children. Health experts agree that excessive exposure to fluoride over a long period of time can cause health problems, but the Centers for Disease Control and Prevention and the American Dental Association say that fluoridated water does not pose any of these risks at the level currently recommended by the Environmental Protection Agency.“Due to the neuropsychiatric risk associated with fluoride exposure,” Dr. Ladapo’s guidance said, “particularly in pregnant women and children, and the wide availability of alternative sources of fluoride for dental health, the State Surgeon General recommends against community water fluoridation.”Dr. Ladapo has played a prominent role in Mr. DeSantis’s administration, often supporting the governor in political fights over pandemic-era health policy. More recently, Dr. Ladapo called for a halt to the use of Covid vaccines earlier this year, citing widely debunked concerns about contaminants in the vaccine.He also contradicted widespread medical guidance about the spread of measles, sending a letter to parents after an outbreak of the disease at an elementary school that said it was up to parents and guardians to determine when their children can attend school, even if those children have not been vaccinated for measles.The guidance on fluoridation in Florida follows heightened attention on the issue after recent statements by Mr. Kennedy, an environmental lawyer who has no medical or public health degrees, and Mr. Trump. Mr. Kennedy declared on social media this month that, as president, Mr. Trump would advise communities to stop adding fluoride to drinking water. Mr. Kennedy described the chemical as “an industrial waste associated with arthritis, bone fractures, bone cancer, IQ loss, neurodevelopmental disorders and thyroid disease.”In a recent interview with NBC News, Mr. Trump said the idea of doing away with fluoridation “sounds OK to me.”Sheryl Gay Stolberg More

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    RFK Jr says Trump would push to remove fluoride from drinking water

    Robert F Kennedy Jr, a prominent proponent of debunked public health claims whom Donald Trump has promised to put in charge of health initiatives, said Saturday that the former president would push to remove fluoride from drinking water on his first day in office if elected.Fluoride strengthens teeth and reduces cavities by replacing minerals lost during normal wear-and-tear, according to the US Centers for Disease Control and Prevention. The addition of low levels of fluoride to drinking water has long been considered one of the greatest public health achievements of the last century.Kennedy made the declaration Saturday on Twitter/X alongside a variety of claims about the heath effects of fluoride.“On January 20, the Trump White House will advise all U.S​. water systems to remove fluoride from public water,” Kennedy wrote. Trump and his wife, Melania Trump, “want to Make America Healthy Again”, he added, repeating a phrase Trump often uses and links to Kennedy.Trump told NBC News on Sunday that he had not spoken to Kennedy about fluoride yet, “but it sounds OK to me. You know it’s possible.”The Republican nominee declined to say whether he would seek a cabinet role for Kennedy, a job that would require Senate confirmation, but added: “He’s going to have a big role in the administration.”Asked whether banning certain vaccines would be on the table, Trump said he would talk to Kennedy and others about that. Trump described Kennedy as “a very talented guy and has strong views”.The sudden and unexpected weekend social media post evoked the chaotic policymaking that defined Trump’s White House tenure, when he would issue policy declarations on Twitter at virtually all hours. It also underscored the concerns many experts have about Kennedy, who has long promoted debunked theories about vaccine safety, having influence over US public health.

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    In 1950, federal officials endorsed water fluoridation to prevent tooth decay, and continued to promote it even after fluoride toothpaste brands hit the market several years later. Though fluoride can come from a number of sources, drinking water is the main source for Americans, researchers say.Officials lowered their recommendation for drinking water fluoride levels in 2015 to address a tooth condition called fluorosis, that can cause splotches on teeth and was becoming more common in US kids.In August, a federal agency determined “with moderate confidence” that there is a link between higher levels of fluoride exposure and lower IQ in kids. The National Toxicology Program based its conclusion on studies involving fluoride levels at about twice the recommended limit for drinking water.A federal judge later cited that study in ordering the US Environmental Protection Agency (EPA) to further regulate fluoride in drinking water. US district judge Edward Chen cautioned that it’s not certain that the amount of fluoride typically added to water is causing lower IQ in kids, but he concluded that mounting research points to an unreasonable risk that it could be. He ordered the EPA to take steps to lower that risk, but didn’t say what those measures should be.In his X post Saturday, Kennedy tagged Michael Connett, the lead attorney representing the plaintiff in that lawsuit, the environmental advocacy group Food & Water Watch.skip past newsletter promotionafter newsletter promotionKennedy’s anti-vaccine organization has a lawsuit pending against news organizations including the Associated Press, accusing them of violating antitrust laws by taking action to identify misinformation, including about Covid-19 and Covid-19 vaccines. Kennedy is on leave from the group but is listed as one of its attorneys in the lawsuit.What role Kennedy might hold if Trump wins on Tuesday remains unclear. Kennedy recently told NewsNation that Trump asked him to “reorganize” agencies including the US Centers for Disease Control and Prevention, the National Institutes of Health, the Food and Drug Administration and some agencies under the Department of Agriculture.But for now, the former independent presidential candidate has become one of Trump’s top surrogates. Trump frequently mentions having the support of Kennedy, a scion of a Democratic dynasty and the son of former attorney general Robert Kennedy and nephew of John F Kennedy.Kennedy traveled with Trump on Friday and spoke at his rallies in Michigan and Wisconsin.Trump said Saturday that he told Kennedy: “You can work on food, you can work on anything you want” except oil policy.“He wants health, he wants women’s health, he wants men’s health, he wants kids, he wants everything,” Trump added. More

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    Robert F. Kennedy Jr. Says Trump Will Seek to Remove Fluoride From Drinking Water

    Robert F. Kennedy Jr. said Saturday that among the first acts of a second Trump administration would be to “advise all U.S. water systems to remove fluoride from public water,” a stunning potential reversal of what is widely considered one of the most important public health interventions of the past century.The statement, posted on social media, is among the more concrete pledges made by Mr. Kennedy — a former independent presidential candidate who is now backing Mr. Trump — in his capacity as a top adviser on Mr. Trump’s transition team. It also raises the specter of an all-out assault on public-health expertise should Mr. Trump win next week’s election, a prospect that has already caused significant alarm among experts across the medical and environmental fields.As president, Mr. Trump would not have the power to order states and municipalities to remove fluoride from their water supplies; fluoridation is a matter of local control.But a presidential pronouncement would inject the White House into a debate that stretches back to the 1950s, when conspiracy theories swirled around fluoridation, with critics claiming it was a Communist plot to poison Americans’ brains — a view that was memorably parodied in Stanley Kubrick’s film “Dr. Strangelove.”More recently, however, there has been scientific debate around the practice, with some studies suggesting that excess exposure to fluoride — at levels twice the amount recommended by the Environmental Protection Agency — could harm infants’ developing brains. But scientists, including those at the federal government’s National Toxicology Program, say more research is needed to understand whether lower exposure to fluoride has an effect.The process of adding small amounts fluoride to drinking water, or fluoridation, began about 80 years ago to prevent tooth decay. That effort, public health officials say, has been extraordinarily successful. A majority of Americans today live in water systems that are fluoridated, according to the Centers for Disease Control and Prevention, which lists fluoridation as one of the 10 great public health achievements of the 20th century.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe. More