COLUMBIA — A dial spins slowly clockwise on a basement pump at Columbia’s water treatment plant in McBaine.

Outside, in the cold late-autumn air, millions of gallons of water roar in massive, swimming-pool size softening tanks. A gurgle rises from three-feet deep channels built under zigzagging walkways, carrying water to filters. With each revolution of the dial in the basement, what engineer Mike Anderson calls a “squirt” of whitish-red liquid finds its way to the filtered water.

It’s a seconds-long process that has occurred virtually unimpeded at the plant since 1973. Missourian reports show only a five-month period in late 1972 when artificial fluoridation was below recommended standards because of equipment failure.

But these days, the pumps hum constantly. Along with nearly three out of four Americans who receive public drinking water, Columbia residents are getting water treated with fluorosilicic acid. Since the closing days of World War II, the same chemical has been delivered into public water supplies under the mantle of fighting tooth decay.

Nationwide, though, tenuous alliances of political, social and economic activists in hundreds of communities big and small have joined forces to lobby against fluoridation and to argue that the tide of evidence about fluoride‘s effects has shifted.

While opponents of the practice bombard elected officials with a medley of reasons to end fluoridating drinking water, health organizations stand behind research that indicates fluoridation is the best investment to prevent tooth decay. The debate is on track to play out in Columbia during the coming months.

The elevator pitch

Amy Bremer, a young mother with another child on the way, stood before the Columbia City Council on Nov. 19 to give a PowerPoint presentation called “Six Reasons to End Fluoridation Now.” Crammed with statistics, her slides flashed on monitors throughout the chamber. She spoke quickly, an efficiency bred from motherhood and from her experience as a chemical engineer discussing scientific matters. Still, her allotted five minutes expired in the midst of her arguments.

“The city of Columbia is doing what no single doctor can do,” Bremer argued breathlessly. “Prescribing medication … and they don’t have your consent.”

Bruce Summers, a young Columbia father, took up the cause two weeks later. He chose a rhetorical approach.

“Would a doctor prescribe medicine through the water supply? The answer should be no,” Summers said.

The two voices are part of a growing national coalition of anti-fluoridation advocates.

Bremer received guidance from Brent Stafford, a community activist in O’Fallon who helped persuade officials there to stop adding fluoride to the water.

“Give them an array of concerns,” Bremer recalled Stafford advising her. It’s a refrain with anti-fluoridation activists, who say they’re battling generations of misconceptions to an audience with varied interests.

“I think some people are not reviewing the current research,” Stafford said. “They are regurgitating the same conventional wisdom that they’ve been accustomed to for a number of years.”

An accidental discovery

Fluoridation began as one man’s occupational curiosity.

Frederick McKay, an East Coast-educated dentist, moved to Colorado to open a practice in 1901. McKay noticed that while residents in Colorado Springs exhibited what then was known as “brown stain” on their teeth, they showed no signs of tooth decay. It wasn’t the best place for a dentist to set up shop.

In his travels throughout Colorado, South Dakota and Idaho, McKay made similar discoveries. He rightly assumed the issue sprouted from the drinking water supply and encouraged changing its source. The staining stopped.

In 1939, after years of in-depth study, McKay and other researchers published a report in the American Journal of Public Health isolating naturally occurring fluoride as the agent that was causing the stains.

On Jan. 25, 1945, the same day the German army called it quits on the bloody “Battle of the Bulge” offensive, Grand Rapids, Mich., became the first city to fluoridate its drinking water. Grand Rapids acted on subsequent research, extending McKay’s work, that suggested artificial fluoridation fought decay.

Writing once again in the Journal of Public Health in 1948, McKay praised the “some twenty-five communities in this country (that) have accepted the evidence as sufficiently conclusive to warrant the addition of fluoride in a proper proportion to their domestic water supplies as a means of reducing the decay rate.”

Ongoing studies in the 1950s suggested younger children’s teeth were stronger after fluoridation.

The practice subsequently ballooned. According to the Centers for Disease Control, 74 percent of Americans had access to fluoridated water in 2010. In April, the Missouri Dental Association reaffirmed its assessment of fluoridation as “safe, necessary and effective in fighting tooth decay.”

Despite resounding scientific endorsements, the practice has not been without controversy.

Caveats emerge

Advocates point to changes in data and regulations as mounting evidence of the need to end fluoridation.

A 2005 Centers for Disease Control report showed the brown stain McKay discovered, now known as fluorosis, affects more than 40 percent of American children between ages 12 and 15. The study showed a 9 percent increase in serious fluorosis cases between 1986 and 1999 among children.

But charges of health issues don’t stop there.

In her presentation to the council, Bremer mentioned a study by Harvard researchers published this summer in the Environmental Health Perspectives journal that linked higher levels of fluoride with decreased IQs.

The researchers for that study, however, included data from parts of rural China. In these towns, fluoride levels reach rates up to three times greater than the maximum contaminant level identified by the Environmental Protection Agency in drinking water and 20 times greater than normal levels in Columbia. The authors also could not identify at what dosage IQ issues become prevalent.

Still, health groups have taken action. Responding in part to fears that American children might be overexposed to fluoride, the U.S. Department of Health and Human Services in 2010 lowered the maximum recommended dosage from 1.2 milligrams per liter to 0.7 milligrams per liter.

Columbia lowered its levels in January 2011. At the plant, operators test fluoride levels every other hour and jot down readings in an oversize ledger. Jars of chemicals for safety tests line the shelves in the plant’s laboratory. Two faucets constantly run samples of treated and untreated water. A large computer screen tracks chemical levels at each of the city’s water pumps.

“We have to follow all the guidelines,” Anderson said, flipping through a thick manual of drinking water safety regulations produced by the Missouri Department of Natural Resources.

The Missouri Dental Association stands behind the federal Health Department’s revised guidelines as a sound investment in public health. Executive Director Vicki Wilbers pointed to a study published in the Journal of Public Health Dentistry that found fluoridation saves communities money on dental care. In cities with more than 20,000 people, savings can reach $38 for each dollar spent on fluoride.

Ending the practice is a choice communities cannot afford, both in terms of dollars and health risks, Wilbers said.

“I think the health departments in the counties need to be very concerned about this,” Wilbers said.

An old fight, with new legs

Battle lines in this debate are drawn in roughly the same way nationwide: grass-roots political organizers on one side, health professionals on the other. Politicians find themselves in the middle of arguments that can become heated.

J.C. Standlee, a Jefferson City-based dentist and active member of the Missouri Dental Association, has monitored the movement. He said the opposition often falls into a few camps: Those who want only natural elements in their water, those who argue fluoridation should be a personal choice and those interested in saving money.

Advocates can convene at any of numerous online destinations. One of the major groups, the Fluoride Action Network, sends group emails highlighting the 300 or so communities that have voted down fluoridation in recent years, with such subject lines as “VICTORY IN WICHITA.” The Kansas metropolis of more than 380,000 voted in November to keep artificial fluoride out of its water and thus far is the largest U.S. city to make that choice.

With national news outlets looking on, the City Council in Portland, Ore., voted unanimously in September to begin fluoridating public water after holding out for several decades.

After hours of public testimony, the council convened for a vote on Sept. 19. In a recording of the meeting, Mayor Sam Adams calls for order amid jeering from the public as the council laid out its arguments in favor of fluoridation. The crowd interrupted Commissioner Randy Leonard as he listed organizations supporting the practice.

“The days of Portland being the largest city in the United States that has not taken action to fluoridate our water hopefully is over,” Leonard said after reciting the list, eliciting groans from the audience and shouts of “Freedom of choice!”

“That’s enough,” Adams responded, pounding the gavel on the table. “Enough, or you’re going to get out of here.”

Sifting through the facts

Such outcries do nothing to improve what anti-fluoride groups call a stigma against their point of view. Famously, a group of anti-fluoride advocates in the 1950s argued the additive was a Communist plot with designs on mind control. Other narratives suggest that fluoride influenced election outcomes and that the chemical was added to drinking water in concentration camps to make Jewish prisoners docile. Mainstream science rejects these claims.

Bremer and Stafford shrug off those associations. Bremer points out that, since the 1950s, thousands of health professionals and 13 Nobel laureates have argued against fluoridation or expressed reservations about the practice. The passage of time has led a status quo, they say, that is outdated, in much the same way the use of asbestos and other industrial products have been found to be harmful.

“There’s a huge difference between natural fluoride and the industrial waste they use in our drinking water,” Stafford said. He cited a 1934 article in the Journal of Industrial & Engineering Chemistry finding artificial fluoride to be “85 times as toxic” as naturally occurring calcium fluoride.

The figure, a popular citation in anti-fluoride arguments, comes from the lethal dosage found in lab mice for both naturally occurring and artificial fluoride compounds. Consuming lethal amounts of artificial fluoride from drinking water would require swallowing thousands of liters of treated water per day, according to the figures from the report.

Columbia’s fluorosilicic acid comes from a company called Mosaic. City officials received a certificate from the company showing the fluoride was produced in Florida.

Two or three times a year, depending on water demand, a truck pulls up to a white storage tank at the rear of the treatment plant offices. Black block letters spell out the chemical’s name on the side of the two-story structure. The liquid fluoride flows from the delivery truck through a valve, not unlike filling up a gas tank in reverse.

Bremer said there are reputations to protect and liability concerns for those who endorse fluoridation, which can create conflicts of interest and cloud the truth.

But Standlee and public health organizations remain unconvinced. The Jefferson City dentist estimates that among the children he treats surgically for severe tooth decay, 90 percent of them grew up on nonfluoridated water.

Standlee’s review of all the relevant literature has led to one conclusion about whether he has any caveats when endorsing water fluoridation.

“No,” he said.

Fluoride’s future in Columbia

Bremer and Summers have gained at least one set of sympathetic ears.

Sixth Ward Councilwoman Barbara Hoppe urged city staff to study the literature on fluoridation and to come back with recommendations. Her concerns about pharmaceuticals in the drinking water mesh with worries about fluoride’s impact on bone health.

“I think it’s worth taking a second look,” Hoppe said, noting that she’s been drinking bottled water with natural fluoride content for years.

Hoppe’s interest in the issue predates Bremer’s involvement. Hoppe used to be one of Summers’ neighbors, and she said the two may have had talks in the past about water quality.

It’s not the rapid change Bremer and others might have envisioned. There would be no quick stoppage, as happened in O’Fallon. Following her remarks and those of Summers, Mayor Bob McDavid said the council would wait for recommendations from the Columbia/Boone County Board of Health, which is set to meet on Jan. 10.

Hoppe said she’s thought about how the city might use any money it saves by ending fluoridation.

“The other option that I thought it was worth looking at was to take the amount of money we use to fluoridate water and specifically direct it or target to the most vulnerable populations in Columbia so that they have good dental treatment and care,” Hoppe said.

Although it’s been suggested in New Jersey and elsewhere, there is no Missouri legislation — proposed or on the books — requiring fluoride treatment. As cities make their decisions, dental association director Wilbers said, it’s important for state agencies to act in concert and to keep residents informed.

In response to the practice ending in Missouri communities, advocacy groups have vowed to push statewide legislation that would require public notice a month before fluoridation ceases.

For all the arguments on either side, a few outcomes are clear should the city cease fluoridation. The Water and Light Department would save roughly $50,000 per year, and the fluoride in Columbia’s drinking water would drop to about 0.3 milligrams per liter. That’s the level found in the natural well water pumped through the plant.

The dance of the dials would stop at the water treatment plant, and the city would probably find its way onto advocacy groups’ lists of success stories. The national political question, however, would be far from decided.

Supervising editor is Scott Swafford.