Whatever kills you will probably be very, very small. It could be a few misplaced molecules in your genome, a buildup of lipids in your artery, or a virus so tiny that a high school chemistry lab’s microscope wouldn’t come close to discerning its spiky form.

Unlike your ancestors, you will be given a chance to contemplate this smallness—to understand, as you have understood nearly all of your life, that death comes in invisible packages, and that it can be anywhere—in the rays of the sun, on the skin of unwashed fruit, in the oil that impregnates your french fries.

Before the cholesterol molecules knock you to the kitchen floor, you will also confront some microscopic things that have been foisted upon you by something huge. Maybe you’ll trust the government, corporation, or scientific establishment that gave you this invisible gift. Maybe you won’t. Perhaps you’ll come to worry about some of those tiny things—the genetic tumblers that have been turned in your tomato, or the chemicals in your children’s vaccines.

For more than a century, Americans have been fretting about these sorts of ghosts. When cities started adding chlorine to their water supplies, in the early 1900s, it set off public outcry. The government was dumping chemicals into water! Milk pasteurization inspired fierce opposition, too. So did early smallpox vaccines.

None of these, though, has inspired quite the same backlash as fluoride. First added to an American water supply at the end of World War II, fluoride has been the subject of controversy, hysteria, conspiracy theories, reasoned argumentation, and bitter municipal friction since 1949.

This agitation is no aberration. The story of fluoridation reads like a postmodern fable, and the moral is clear: a scientific discovery might seem like a boon. But in this anxious world, when a very big entity forces a very small substance into people’s lives, some of those people are going to get upset. It’s worth paying heed to this moral, because in fluoridation controversies, we can see the template for so many disputes to follow. Debates over electromagnetic fields, nanotechnology, GMOs, vaccines, and, to a lesser extent, climate change, all follow the pattern established by fluoride.

On the whole, fluoride makes for an unsexy flashpoint. It is an ion beloved by dentists. Added to drinking water at concentrations of around one part per million, fluoride ions stick to dental plaque. From there, they help reverse decay. Placed in drinking water, fluoride can serve people who otherwise have poor access to dental care. “It’s been quite a successful public health program,” Dr. Howard Pollick, an American Dental Association spokesperson and University of California, San Francisco clinician, told The Daily Beast.

As a means of preventing tooth decay in those cities that do fluoridate, the practice certainly looks like a success. But fluoride been rejected by most European countries and regularly defeated by citizen’s referenda in the United States (most recently and prominently in Portland, Oregon, last year). As an example of good science-and-society policymaking, the history of fluoride may be more of a cautionary tale.

Fluoride first entered an American water supply through a rather inelegant technocratic scheme. In 1945, just a few years after the discovery that fluoride could slow tooth decay, the United States Public Health Service chose two neighboring cities in Michigan. They fluoridated the water in Grand Rapids. They used Muskegon as a control. (I’m indebted, here, to the wonderful historical work of Donald R. McNeil). To put it rather uncharitably, the USPHS practiced a major dental experiment on a city full of unconsenting subjects.

Not to be left behind, progressives in neighboring Wisconsin clamored to join the cutting edge of public health. Dental leaders barnstormed the state, and cities began to fluoridate.

The backlash started in Stevens Point, a small city in central Wisconsin, where the city council decided to introduce fluoridation in 1949. Led by a local activist who adapted popular songs into anti-fluoride ballads, and who claimed that fluoride was still experimental (which was true) and highly poisonous (less true), citizens forced the city to hold a referendum. In secret, before the referendum, the council went ahead and fluoridated the water anyway. Once discovered, this maneuver did not endear the councilors to their constituents. The citizens of Stevens Point defeated fluoridation by a healthy margin.

Throughout the fifties, in city after city, fluoridation became the subject of fierce debate. Was it too experimental? Was it rat poison in the water? Did it cause cancer? Was it, along with the polio vaccine and mental hygiene programs, a communist plot to incapacitate American citizens, as the Keep America Committee claimed in 1953?

Since the 1950s, fluoride has adapted itself to the prevailing concerns of the time. When communism was a threat, it was construed as a communist plot. As the environmental movement grew in prominence, fluoride additives were grouped with dangerous pollutants, and later portrayed as the product of a corporate scheme (Greenpeace has opposed both fluoridation and water chlorination).

In 1992, in the John Birch Society magazine, libertarian writer Murray Rothbard chalked up fluoridation to the excesses of the welfare state. More recently, channeling the zeitgeist, Republican Representative Dana Rohrabacher has invoked the language of individual rights and government interference in his anti-fluoride stance. In other words, fluoride is a broad-spectrum, bipartisan, long-lasting magnet for dissent. Certain features of its history suggest why this may be the case.

As Brian Martin, a social scientist at the University of Wollongong, in Australia, and a researcher of fluoridation debates, explained to me, fluoridation controversies follow a pattern that’s been replicated in debates over everything from GMOs to vaccines.

First, scientists work in partnership with a governmental agency, an industry, or both, in order to develop some new tool or policy. Eager to apply their findings to the public good, they don’t get much citizen input on their project, and, says Martin, “they’ve already started to implement it before anyone gets a say” (by, for example, fluoridating the entire city of Grand Rapids). And when citizens do protest, the government or corporation may not take those concerns seriously (recall the city council of Stevens Point, secretly starting fluoridation before a referendum had even been held). The result is a familiar narrative, in which noble citizen dissenters face up to a powerful alliance between scientists and government or corporate interests.

The critical detail here, though, seems to be the lack of control that citizens have over policies like fluoridation, or mandatory vaccinations, or electromagnetic waves from cellphones. More blatantly dangerous practices—such as putting carcinogenic flame retardants in couches—don’t inspire quite the same level of backlash, because there, at least, consumers have the illusion of control over their chemical fates. Something like fluoride, which is too small for normal filters, yanks away that feeling of agency.

Meanwhile, as with nearly every other subject of scientific inquiry for the past 50 years, it’s not hard to cast aspersion on fluoride. There’s always a study, a story, a suspicion, a dental dissenter—something that can be spun into a plausible image of doubt. And, in the case of fluoride, at least, that doubt might actually be justified. There are reasons that European countries tend to avoid fluoride. The stuff really does have toxic effects at concentrations that aren’t that much higher than what crops up in our water.

Really, is it any wonder that fluoride should freak people out? It’s a story of uncertainty and powerlessness, and it feeds into that most modern of anxieties: the feeling of being sandwiched between an entity too large to grasp—the government; science—and something too small too see—the ions in your water; the waves passing through the air.

“It’s a paranoid universe,” says the spymaster in Philip Roth’s Operation Shylock, “but don’t overdo it.”

Don’t overdo it, indeed. But what to do?

For a start, a little transparency can help. Have you seen the national Centers for Disease Control’s overcrowded webpages, even on hot-button issues like vaccination? Have you looked around the American Dental Association website for an explanation of how fluoridation actually works? (Hint: it’s buried in a 71 page-long PDF.) Have you tried to access the research that your tax dollars finance, almost all of which is kept behind a paywall? Has your doctor ever told you what’s in the fluid that she’s injecting into your arm?

The policy recommendations that emerge from scientific institutions might seem like the work of a distant, inaccessible, exclusive, homogenous, and byzantine elite. After all, they come from a world that is, for 99 percent of Americans, distant, inaccessible, exclusive, homogenous, and byzantine.

Brian Martin, the Wollongong professor, suggests that randomly selected panels of citizens could help formulate policy on topics like fluoridation. That strategy has been used in some cases to help determine GMO policy. At least in principle, it gives regular citizens a voice. At the same time, it’s a more sober, well-informed process than holding a referendum, which tend to give a platform for extremists and scare-mongers.

After all, science-and-society issues won’t be resolved just by communicating science to citizens. Citizens, perhaps, need to feel like they can communicate something to science.

*Original article online at https://www.thedailybeast.com/anti-fluoriders-are-the-og-anti-vaxxers?ref=scroll