Fluoridated drinking water is coming under the gun again, in large part because of concern about the rising incidence of developmental neurological disorders like autism and ADHD. Could this widespread chemical additive be to blame?
Philadelphia’s drinking water is fluoridated, so we all want to know the answer.
While the science on this subject is inconclusive, enough alarms have been raised for the United States Environmental Protection Agency in 2009 to place fluoride – an ion of the element fluorine – on a list of “chemicals with substantial evidence of developmental neurotoxicity.” And research continues to raise disturbing questions about its use.
A group called Fluoride Free Philadelphia has been crusading for the Philadelphia Water Dept. to stop fluoridating our water supply since 2013. It has not met with direct success so far.
But beginning just last month, PWD lost a major customer as a result of fluoridation. Bucks Co. Water Supply Agency, which serves 385,000 people, stopped buying Philadelphia water, switching to the Forrest Park Water Plant in Chalfont, Pa. On its website, BCWSA is telling its users, “BCWSA has heard your request and is happy to announce that our customers have a choice to use fluoride or not through your dentist instead of being mandated through your water supply. The new source does not have fluoride added to it.”
Fluoridating water supplies is about 100 years old. Its purpose is to reduce dental caries (cavities), a costly ailment that bothers most people, especially in their early years. Water laced with the fluoride ion in one of several compounds has been shown to reduce tooth decay by as much as 40%, all for a price of $1 person per year. It’s the cheapest dentistry ever found.
Most American water has long been fluoridated – and long attracted controversy for that reason.
Early opponents of fluoridated water acquired a bad name because some of them were crackpots with a philosophical ax to grind but with no grasp of medicine. The John Birch Society in the 1950s, founded by John Koch (father of today’s Koch Brothers), saw creeping communism in public water and slammed it as “mass medicine.”
Clinicians shrank in horror from such rhetoric. Attempts to link fluoridation with widespread diseases in the 20th century largely failed. The anti-fluoride movement died down.
By the turn of the century, however, clinicians were becoming more curious about the causes of developmental disorders, which are becoming more common. Chemicals in the environment are one obvious suspect.
PWD has wisely deferred to the Philadelphia Dept. of Public Health for an opinion on this issue.
Last year, Beverly DeCer of Fluoride Free Philadelphia met with Deputy Mayor Donald Schwartz of DPH to present evidence against fluoridating water. DPH spokesman Jeff Moran advised, “After meeting with Ms. DeCer, Health Dept. staff reviewed the literature that she submitted concerning neurotoxicity of fluoride. These studies, most of which originated outside of the United States, were felt to be scientifically flawed and did not provide evidence of an association between fluoride, at concentrations delivered through drinking water, and neurotoxicity.”
But one of the first researchers to report this effect was Dr. Phyllis Mullenix, trained at Harvard, who in 1995 published in the journal Neurotoxicology & Teratology detailed research demonstrating neurological impairments in rats raised on water laced with sodium fluoride. Her research, run many different ways, consistently produced evidence of abnormalities.
Ironically, Dr. Mullenix was working for a dental-research institute at the time. Her original goal was to investigate other dental compounds, such as mercury; she started with fluoride as a control, expecting to find nothing.
Her findings rocked the dental profession. Critics jumped on her work but complained that her protocol was too specific and demanding to be easily replicated. In other words, no one funded them to do the painstaking work that was needed.
Dr. Mullenix did not get a chance to pursue her studies either. A few days before her article was published, she was fired. She remains a respected academic at Clark University, but no one wants to fund her to work on fluoride either.
That’s no accident, charges DeCer, a registered nurse, who founded FFP. That’s because fluoridation chemicals are big business now. PWD alone pays $685,000. And fluoride producers are powerful because fluoridation treatments are a byproduct of major industries such as aluminum smelting. Alcoa has clout. Based in Pittsburgh, Pa., it is the third-largest aluminum producer in the world.
“We are a ‘corporatocracy,’ not a democracy,” says DeCer. “Fluoride was the backbone of industry. They bought and paid for any science that said it was good for dental health.”
There’s no question that private industries have more control over funding research into commercial chemicals in the United States than they do in Europe, for instance. It may be no coincidence that fluoridated water remains rare in Europe (even though European teeth are by and large as good as ours).
In 1999 Dr. Roger Masters, a senior professor at Dartmouth University, and Myron Coplan published “Water Treatment with Silicofluoride and Lead Toxicity” in an influential journal. They found elevated levels of lead, an element known to cause neurological damage, in waters treated with two other fluoridation compounds. However, the federal Centers for Disease Control & Prevention said their article is “poorly written and provides insufficient detail on study method to allow a full evaluation.” Definitely Masters & Coplan cast a wide net in their research – too wide, perhaps.
It’s not clear why PDH regards work by Americans as the touchstone of all research. A stroll down any corridor inside the Hospital of the University of Pennsylvania is like a visit to the United Nations. Medical research is an international field.
In 2003 A. Shashi of Patiala, India published a research report on sodium fluoride in rabbits. He too found neurotoxic changes in the rabbits’ brains. Perhaps because he was not American, no American has bothered to criticize his work in a professional forum.
American enough, for sure, is Dr. Philippe Grandjean of the Harvard School of Public Health. In recent years his research team has unleashed a torrent of disturbing data from different parts of China where natural levels of fluorine vary in the drinking water due to geology. They have found a correlation between higher fluorine levels and lower IQ.
Dr. Grandjean’s work has been savaged because, like Masters & Coplan, it casts such a broad net. Its data-reporting sources are annoyingly variable and uncontrolled by the researchers – not the gold standard in research. In epidemiology, however, one always begins with messy data like these and keeps working to refine them.
Dr. Grandjean is unrepentant. He said this year the number of chemicals known to hinder child brain development have doubled from six in 2006 to 12 today. Fluorine he counts among them.
And it keeps on coming. This year, Zong-Ping Liu et al. at McGill University, the “Harvard of Canada”, published in the Archives of Toxicology their research probing exactly how sodium fluoride causes fetal abnormalities in rats.
COMPLEX RISKS, TOUGH CHOICES
Studies like the work cited above are what placed fluorine compounds on the EPA’s watch-list for developmental neurotoxicity. But this does not mean the EPA has determined that artificially fluoridated tapwater is in fact dangerous. Much more research would have to be done before clinicians can make that call.
“It can be difficult to separate the various causal factors when doing research in this field,” commented Dr. Marvin Schulte, who chairs the Dept. of Pharmaceutical Sciences at University of the Sciences. (He does research on a different neurotoxin: nicotine.) Research samples of real-life populations must control for other agents present in a sample (say, a city’s drinking water) that might be responsible for positive results.
In addition, a toxic effect may only appear, or may be stronger, if two or more agents enter the body at the same time. So fluoride might be more harmful (or less harmful) when an additional element is present than when it is not.
“These toxins may have overlapping effects. Synergistic effects are well known,” noted Dr. David Jett. This man runs the National Institutes of Health’s CounterACT program within the National Institute of Neurological Disorders & Stroke; its mission is to sniff out chemical threats in neurology.
Thorough research would call for studying not just fluoride in water, then, but every other chemical in water simultaneously – a daunting assignment.
Furthermore, water is fluoridated by one of three different compounds: sodium fluoride, fluorosilicic acid and sodium fluorosilicate. These chemicals may be metabolized differently, so that conclusions from a study using one may not apply to the others.
Dosage is everything in studies of toxicity. Everything can kill you if you consume enough of it. The question is where lies the threshold at which unwanted effects will start to occur.
Not all fluoride enters the body through water. Fluoride is also present in some foods and in some air pollution.
For these reasons, controlled laboratory experiments may not replicate the effects of fluoride in everyday water supplies. By the same token, studies of different water systems may yield different results, as the chemical mix in various water sources varies infinitely.
Public regulators set minimum safety standards for fluoride content based on current knowledge. But different towns and different governments will have different standards. They may also use different methods of measurement and have different levels of accuracy and supervision, making it hard to compare data from water systems that are not well known to the researcher.
“It is crucial that you have analytical methodology in place to measure that toxin at very low levels,” Dr. Jett explained. Figuring out the right chemistry and technology to do this is not easy and leads at times to disputes between researchers.
Topping off the challenge is a marvelous maze of nature called the human brain. “The brain is highly complex, with a lot of different structures,” Dr. Jett pointed out. Just because chemical A whacks neuron X in a laboratory doesn’t mean it will whack neuron Y as well.
So the current state of scientific knowledge in this controversy is unsettled for good reasons. The main question at this time is what the prudent policy is to deal with this uncertainty.
Backers of fluoridation argue since this widespread practice has well-known benefits but few clearly harmful effects known at this time, it should be continued.
Opponents argue from a viewpoint of “first, do no harm”. Since neurological developmental disorders are on the rise for reasons unknown, they say, we should avoid any unnecessary chemical additives until their impact on the human organism is thoroughly known.
Dr. Grandjean is one of the latter. “To control the pandemic of developmental neurotoxicity, we propose a global prevention strategy,” he has written. “Untested chemicals should not be presumed to be safe to brain development, and chemicals in existing use and all new chemicals must therefore be tested for developmental neurotoxicity.”
All this research implies someone willing to pay for it, however. Funding for basic public-health research is increasingly falling under the knives of budget-slashers. Companies with an interest in selling fluoride have a motive to fund research into its potential benefits – not its potential side effects.
Without targeting fluoride in particular, Dr. Jett said, “There are many thousands of industrial chemicals out there that we believe are toxic. We have a lot of work to do.”
In the meantime, the trend is to lower the dosage of fluoride. Since 1962 the United States had suggested fluoride levels in water could safely range as high as 1.2 grams per liter. In 2011, the recommended maximum was reduced to 0.7 grams per liter.
There are ways to obtain fluoride protection for teeth without swallowing it in water. It can be applied topically, in toothpaste. In this way, it goes directly to the organ fluoride is good for – your teeth – rather than to the organs that don’t need it – your blood and your brain.
But Philadelphia has a lot of poor people. Poor people lose a lot of teeth and get a lot of dental work at public expense. Maybe they can’t always afford toothpaste. For this population, fluoridation may be a good deal – as long as it doesn’t harm our children.