The Devastating Effects of Fluoride Toxicity

 James Odell, OMD, ND, LAc

The History of Fluoride

Fluoride is the ionic form of fluorine, the thirteenth most abundant element in the earth’s crust. It is released into the environment naturally in both water and air. Fluoride gradually accumulates in the environment from volcanic emissions, dissolution of minerals, and industrial byproducts. 

Halfway through the twentieth century, fluoride attracted the interest of toxicologists due to its deleterious health effects on human populations, particularly for those suffering from fluorosis. Fluorosis is characterized by dental mottling and skeletal manifestations such as crippling deformities, osteoporosis, and osteosclerosis. 

The acute toxicity of fluoride is well established. However, until the 1990s chronic fluoride toxicity was largely ignored due to its “alleged good reputation” for preventing dental caries via topical application, in dental toothpaste, and water through fluoridation. In the last decade, interest in its chronic detrimental health effects has resurfaced due to the awareness that this element injuriously interacts with cellular systems even at low doses. In recent years, several investigations have demonstrated that fluoride accumulates in the body and can induce oxidative stress causing lipid peroxidation and protein damage, as well as alter gene expression causing cellular damage and death.

Fluoride Research

The literature about the occurrence of fluoride in the environment and its relationship to human health is quite extensive and spans a wide variety of disciplines, including the fields of medicine, dentistry, environmental and occupational health, and toxicology. There is even an entire journal (Fluoride) devoted to the dissemination of research in this area published by the International Society for Fluoride Research. Consequently, any attempt to summarize the state of knowledge concerning fluoride and human health is necessarily limited to a broad overview. 

Given that limitation, the chief purpose of this article is to provide a framework for the toxic impact of fluoride at the molecular, cellular, and multisystem levels. It will be shown how fluoride causes a detrimental effect on cellular function, neurology, intelligence quotient (IQ), and the endocrine system, particularly on the thyroid and pineal gland.

Despite abundant evidence that fluoride is toxic even at low levels and accumulates in organs and tissues over time, it is still deliberately added to public water. 

Community Fluoridation in the U.S.

Water fluoridation is the practice of adding hydrofluorosilicic acid (H 2 SiF 6), sodium fluoride (NaF), or sodium fluorosilicate (Na 2 SiF 6) to drinking water, allegedly to prevent tooth decay.  Communities primarily add hydrofluorosilicic acid to their water supplies as the most used fluoride chemical for water fluoridation. This chemical is derived from waste created by the phosphate fertilizer industry and this process will be described later in this article.  One of the little-known facts about this practice is that the United States, which fluoridates over 70% of its water supplies, has more people drinking fluoridated water than the rest of the world combined. Even if you do not live in a community where fluoride is added to water, you will still be getting a dose of it through cereal, soda, juice, beer, and any other processed food and drink manufactured with fluoridated water.

Fluoridation Rejected in Other Developed Countries

However, Western European countries have generally followed a different path, with the majority opting to reject fluoridation from the beginning, and others discontinuing this practice during the last part of the 20th Century. Thus, most developed nations, including all of Japan and 97% of Western Europe, do not fluoridate their water. Comprehensive data from the World Health Organization reveals that there is no discernible difference in tooth decay between the minority of Western nations that fluoridate water and the majority that do not. The tooth decay rates in many non-fluoridated countries are now lower than the tooth decay rates in fluoridated ones.

Fluoridation From Groundwater Contamination

Another source of fluoride is groundwater contamination, which is also a serious public health issue in some countries. It is estimated that more than 200 million people from different countries are affected by fluoride-related groundwater issues and health problems. The highest among these are from the countries in Africa, Asia, South America, and Mexico. 

Toothpastes Contain Fluoride - With a Warning Label 

Thus, humans are exposed to fluoride primarily through their diet and water that has been fluoridated. Additionally, the vast majority of toothpastes contain fluoride and are required to have a warning label. The use of fluoride toothpaste, particularly during early childhood, presents health risks. This is why the FDA requires a poison warning on every tube of fluoride toothpaste now sold in the US. Not surprisingly, numerous studies have found that many children ingest a significant amount of fluoride each day from toothpaste alone. Studies show that children across the globe are more vulnerable than adults to fluoride contamination.

Fluoride Accumulation in the Body

After ingestion, fluoride passes along the gastrointestinal tract and into the plasma. Over time, fluoride accumulates in the extracellular matrix where it makes its way into cells of the organs such as the liver, spleen, pancreas, and kidney, as well as bone and connective tissue, leading to potential chronic toxicity. 

Concern by Toxicologists

Over the years there has been a strong concern by numerous toxicologists, physicians, and health educators as to the safety of fluoride in public water at the current exposure levels. Trace amounts of fluoride exist in groundwater even before fluoridation. It has become increasingly clear that fluoridating water supplies is an outdated, unnecessary, and dangerous relic from a 1950s public health culture that viewed the mass distribution of chemicals much differently than scientists do today.

A Myriad of Toxicity from Fluoride

While the public is still told that low doses of fluoride are beneficial for overall teeth integrity, fluoride accumulates in tissue and even at low levels can lead to a myriad of toxicity phenotypes (observable physical properties of an organism). This includes oxidative free radical pathology (oxidative stress), cellular organelle damage and cellular death, and neurological, skeletal, and soft tissue damage. The toxic phenotypes are generally attributed to four mechanisms - the inhibition of proteins, organelle disruption, altered pH, and electrolyte imbalance.1,2,3 

These four mechanisms occur to varying degrees depending on the concentration of fluoride, its route of administration, and each cell’s surrounding environment (the internal terrain). There is not a complete consensus over which downstream toxic phenotype is linked to each mechanism, as each stressor can independently trigger oxidative stress, intercellular damage, and cellular apoptosis (death).4 

Fluoride Inhibits Necessary Enzymes

Fluoride initiates toxicity through a combination of many targets, particularly its ability to inhibit metalloproteins.5 Fluoride’s properties as a protein inhibitor were established decades ago. Starting in the late 1800s, sodium fluoride was identified as a lipase inhibitor. Lipase is an all-important enzyme for the digestion of fats and metabolism of dietary triglycerides as well as cell signaling and controlling inflammation.6, 7  

Later fluoride was found to inhibit a wide range of enzymes such as phosphatases, kinases, hydrolases, as well as other metalloproteins. As of 2018, the protein data bank has collected over 700 proteins crystallized in complex with fluoride. Over 100 of these have had separate, independent enzymatic studies for fluoride inhibition in vitro.8 

Fluoride Interacts with Metals and Interferes with Many Cellular Pathways

While fluoride has been reported in a few select cases to bind directly to amino acids or to displace essential hydroxides, the majority of noted protein interactions are through either: 9, 10, 11

(1) fluoride binding to an essential metal in a metalloprotein’s active site, or

(2) the complexing of fluoride with metal and acting as a substrate 

An estimated 30–50% of bodily proteins require metal (metalloproteins) to function biochemically. Thus, there are thousands of potential targets for fluoride inhibition.12 

Fluoride is strongly negatively charged, and associates with positive sites on proteins. In the case of metalloproteins, fluoride interacts with the essential metals, forming a highly stable, often insoluble complex. Many pathways, particularly glycolysis, nutrient transport, and cellular respiration are inhibited during fluoride exposure, presumably through metalloprotein inhibition.13, 14, 15

Climate Geoengineering Enhances Fluoride Toxicity

Evidence shows fluoride toxicity is greatly enhanced when complexed with metal. Among the most toxic (and most studied) complexes are aluminum-fluoride (AlF3) and beryllium-fluoride (BeF2). Tragically, metals are being sprayed into the troposphere as climate geoengineering. We are being inundated from our atmosphere with aluminum, strontium, barium, and other chemicals, particularly aluminum.16 

Aluminum-fluoride can alter the phosphorylation state of various proteins, particularly through Guanosine-5'-triphosphate  (GTP) mimicry. Guanosine-5'-triphosphate is a purine nucleoside triphosphate. It is one of the building blocks needed for the synthesis of RNA during the transcription process.

Many proteins, including G-proteins (guanine nucleotide-binding proteins), actin, and microtubule-associated proteins, are regulated by GTP binding. Thus, because aluminum-fluoride inhibits GTP this leads to wide dysregulation of functions including cell signaling, transport, and cytoskeleton integrity.17, 18, 19 (More on aluminum-fluoride neurotoxicity later in this article.)

Fluoride Impairs Cellular Organelle 

Prolonged exposure to fluoride can lead to widespread cellular organelle impairment. This disruption is both time - and concentration - dependent. While the sensitivity of each cellular organelle to fluoride varies slightly, in general, fluoride disrupts the cell membrane, mitochondria, endoplasmic reticulum, Golgi, and nucleus (most if not all organelles). The organelle most widely reported to be inhibited by fluoride is the mitochondria. Many mitochondrial proteins are metalloproteins and have been linked to fluoride inhibition.20, 21, 22, 23, 24, 25, 26

Protecting the Mitochondria from Fluoride Toxicity with Nutrients

Not surprisingly, the addition of mitochondrial nutrients to the diet partially rescues the mitochondria from fluoride toxicity.27 B vitamins and lipoic acid are essential in the tricarboxylic acid cycle, while selenium, α-tocopherol, and Coenzyme Q10, can boost the electron transfer system function. Carnitine is essential for fatty acid beta-oxidation and selenium is involved in mitochondrial biogenesis. Fluoride detoxification will be addressed in a future article.

Fluoride Impacts Mitochondria

The last few years have seen renewed interest in mitochondrial inactivation under fluoride exposure as the primary mechanism of fluoride toxicity, as much of the known adverse effects can be attributed to free radical damage.28, 29, 30

Damage to the mitochondria releases free radicals, resulting in oxidative stress. This in turn causes DNA damage, metabolic disruption, ATP hydrolysis, protein inhibition, and intracellular acidification.31 

Fluoride Reduces ATP - Further Damaging the Mitochondria

Fluoride also inhibits metabolism through a reduction in intracellular adenosine triphosphate (ATP) and damage to the mitochondria. ATP is a nucleotide that provides energy to drive and support many processes in living cells, such as muscle contraction, nerve impulse propagation, condensate dissolution, and chemical synthesis. Fluoride reduces ATP both in cells containing mitochondria – which display signs of permanent damage and reduced respiration after fluoride exposure – and in erythrocytes (red blood cells), which lack mitochondria and produce ATP solely through anaerobic glycolysis.32, 33 

Fluoride Damages the Endoplasmic Reticulum and Golgi Apparatus

The endoplasmic reticulum (ER) is a continuous membrane system that forms a series of flattened sacs within the cytoplasm of eukaryotic cells - cells with a nucleus and other organelles. The ER activates stress signaling under fluoride exposure. Prolonged fluoride exposure can severely damage the ER membrane resulting in oxidative stress, and DNA damage.34, 35 The Golgi apparatus is a membrane-bound organelle of eukaryotic cells (cells with clearly defined nuclei) that is made up of a series of flattened, stacked pouches called cisternae. The Golgi apparatus is responsible for transporting, modifying, and packaging proteins and lipids into vesicles for delivery to targeted destinations. It is found in the cytoplasm next to the endoplasmic reticulum and near the cell nucleus. Fluoride inhibits the all-important Golgi stacking necessary for its function. Aluminum fluoride has been shown to adversely affect guanine nucleotide-binding proteins or G-proteins by mimicking the gamma-phosphate of GTP.36 As G-proteins function in signal transduction (cellular communication), their activation has far-reaching implications, especially in Golgi function. G-proteins are also found on the Golgi and are essential for Golgi stacking.37, 38 Aluminum-fluoride also alters the protein coating assembly along the Golgi.39, 40 

Fluoride Irreversibly Damages Cellular Membranes

Last, but not least, fluoride can also irreversibly damage cellular membranes. While most membrane changes are attributed to either oxidative stress, apoptotic signaling, or lipid peroxidation, free or metallo-fluoride can also directly bind actin and change its polymerization.41, 42 Actin is a protein that is an important contributor to the contractile property of cells. Intercellular organelle damage and cell cycle dysfunction during fluoride exposure indicate that one of fluoride’s principal mechanisms of toxicity is intracellular.

Fluoride Induces Acidic pH and Electrolyte Imbalance

Fluoride is a weak acid that enters cells and dissociates, thus releasing one proton per fluoride. At both the single- and multi-cellular levels, fluoride exposure causes acidification and electrolyte imbalance. This results in the loss of calcium, potassium, and magnesium from the plasma and cells.43   The imbalance of electrolytes from fluoride exposure has far-reaching implications for cell homeostasis and signaling disruption. Fluoride exposure is also associated with a drop in intracellular pH (acidification).  

Fluoride’s Absorption, Distribution, and Accumulation

To better understand fluoride’s far-reaching toxicity, it is necessary to track its absorption, distribution, and accumulation or deposition. Fluoride is a bioaccumulative toxin that our bodies attempt to excrete through the intestines, kidneys, and skin. Fluoride is a member of the so-called “bone-seeking” poisons due to its ability to displace hydroxyl groups in the hydroxyapatite that forms the mineral content of our bones. Thus, fluoride targets and deposits into the bones. But the deposition does only target the bones. The extracellular matrix, organs, and glands are all subject to the deposition of fluoride.  

Fluoride is readily absorbed directly through the oral tissues – no need to swallow. In the stomach, a large proportion of fluoride is converted to the extremely hazardous, tissue necrotizing, hydrogen fluoride (HF) molecule, a gas at body temperature. HF then readily migrates through the airways, stomach, and intestines to wreak havoc throughout the body. Hydrogen fluoride can dissociate across the stomach lining causing inflammation. Nonetheless, only 25% of ingested fluoride is thought to be absorbed by the stomach and passed on to other cells; whereas the rest of the fluoride is moved to the intestines.44

The majority of ingested fluoride is absorbed by the small intestine as its anion form (F- ).  Only ~10% of consumed fluoride is never absorbed by the body and excreted through feces.45, 46, 47, 48   The nutrients ingested along with fluoride, especially those rich in calcium, influence the amount of fluoride absorbed by the intestines.49 

Once absorbed, fluoride travels throughout the body via the bloodstream, before being filtered by the kidney and excreted in urine. The renal system is responsible for excreting most of the body’s excess fluoride and is exposed to higher concentrations of fluoride than other organs.  This suggests that it might be at higher risk of fluoride toxicity. Approximately 45–60% of ingested fluoride is excreted in the urine, with the rest re-circulated into the lymphatics or deposited into the bone, connective tissue matrix, nervous tissues, glands, and organs.50, 51 Thus, around half of the fluoride consumed becomes stored in the body and accumulates over time.

Fluoride Is a Neurotoxin and Reduces IQ

One of the gravest concerns is that fluoride is a known neurotoxin and exposure can lead to neuronal damage, reduced IQ, and potential participation in neurodegenerative diseases such as Parkinson’s disease and Alzheimer’s disease. Numerous studies have now found correlations between low IQ and fluoride exposure from fluoridated water and infant formula. Over 60 studies have been conducted in areas with fluoridated water, and most of these studies have reported a lower average IQ in the children of those regions compared with children in areas with normal fluoride exposure. These studies revealed that in fluoridated communities the fetus and the formula-fed infant are the most vulnerable to fluoride’s neurotoxicity. Certain high levels of fluoride in the pregnant women’s urine were found to significantly impact the IQ, or neurodevelopment, of the offspring. In short, the concentration of fluoride in ingested water is significantly associated with the IQ of children. Studies show the greater the exposure the greater the reduction in IQ. 52, 53, 54, 55, 56, 57, 58, 59, 60, 61

In a laboratory setting, fluoride is toxic to neuronal cells. Neuronal cell lines exposed to ≥60 ppm sodium fluoride undergo DNA damage, oxidative stress, mitochondrial agglutination, and cytoskeleton damage.62, 63, 64 Because the primary function of neurons is synaptic signaling, membrane defects from fluoride exposure reduce the overall activity of neurons. 

Rats and mice exposed to fluoride at ≥50 ppm showed decreased nicotinic acetylcholine receptor expression, lowered acetylcholinesterase activity, and damaged myelin and microtubules.65, 66 Rats exposed to 10 ppm NaF and 100 ppm AlCl3 in combination for 30 days showed neuronal shrinkage and inhibition of acetylcholinesterase activity.67 

Fluoride Crosses the Blood-Brain Barrier as Aluminum-Fluoride

While free fluoride is unlikely to pass through the blood-brain barrier, metallo-fluoride, specifically aluminum-fluoride, can cause neurotoxicity. Aluminum fluoride (AlF3 or AlF4) are phosphate mimics and can cross the blood-brain barrier through phosphate transporters.68 Furthermore, aluminum fluoride was found to cause more histopathological changes to brain tissue than sodium fluoride alone, particularly in the neocortex and hippocampus.69 

Some Possible Neurotoxicity from Aluminum May Also Be to Blame

However, it is also possible that some of the neurotoxicity is also due to free aluminum. Free aluminum acts as a neurotoxicant, disrupting the cell membrane integrity of the blood-brain barrier, activating the innate immune response, and potentially increasing dementia.70, 71 Thus, aluminum could be at least partially responsible for fluoride neurotoxicity. We are being inundated with aluminum from climate geoengineering contamination of the skies. This coupled with fluoride from municipal water creates a dangerous neurological combination. 

In conclusion, excess fluoride promotes neuroinflammation in the central nervous system by promoting oxidative stress, activating microglia, and other factors that lead to neurodegeneration, impaired learning ability, and memory dysfunction.

Fluoride Is an Endocrine Disruptor (Thyroid Toxicity and Hypothyroidism)

Fluoride was officially classified by the National Research Council in 2006 as an endocrine disruptor for its ability to inhibit the thyroid at high concentrations. One proposed mechanism is that fluoride interferes with the thyroid's ability to produce thyroxine by causing the disassociation and blockage of the iodine needed for this process.

Halogens are any of the six elements that constitute Group VIIa of the periodic table. The halogen elements are fluorine (F), chlorine (Cl), bromine (Br), iodine (I), astatine (At), and tennessine (Ts).  Because these elements are similar in molecular structure and activity, chlorine and fluorine in public water can displace iodine by attaching to iodine receptors on the thyroid gland.  This can potentially cause hypothyroidism. It is known that fluoride exposure can lead to a decrease in the thyroid hormones triiodothyronine (T3) and thyroxine (T4). Numerous studies have reported a significant decrease in T3 and T4 by fluoride.72, 73, 74, 75, 76

Research conducted with high doses of fluoride reports direct and indirect inhibitory effects on the endocrine system, independent of the thyroid. The most notable targets are the pineal gland, adrenal glands, and the parathyroid. The pineal gland lies outside of the blood-brain barrier and has the highest calcification rate of any organ in the body.77, 78

Fluoride Accumulating in the Pineal Gland

Fluoride has been shown to gradually accumulate in the pineal gland along with calcium, thus calcifying the pineal and potentially disrupting its many critical functions.79, 80, 81, 82

Unfortunately, only a few studies have been conducted on whether fluoride accumulation significantly disrupts pineal gland activity. Those that have tested the output of melatonin production by the pineal gland showed a decreased output in the presence of fluoride. 

Fluoride Also Impacts the Parathyroid Gland

The parathyroid is also impacted by fluoride toxicity. Patients with skeletal fluorosis (the most severe form of fluoride toxicity), are sometimes found to have secondary hyperparathyroidism.83 

In summary, the majority of studies confirm that sodium fluoride increases TSH levels and decreases the concentrations of T3 and T4 produced by the thyroid. Other studies have shown its detrimental effect on the pineal gland and parathyroid. Probably, fluoride may exert adverse effects on insulin levels as well, impairing pancreatic function and resulting in abnormal glucose tolerance. Observations also include decreased levels of cortisol secreted by the adrenal glands. More research needs to be conducted in this area.

Fluoride Potentially Contributes to Cancer

Epidemiological studies designed to identify the carcinogenic potential of chronic fluoride exposure face some inherently difficult challenges.  One of the biggest problems is that cancer diagnosis typically occurs years to perhaps decades after exposure to the causal factors, during which time individuals migrate both into and out of the study area. Because fluoride is principally deposited in the skeleton, the possibility that it might contribute to bone cancer has received considerable attention from researchers.84, 85, 86  

Some laboratory studies of animals have shown evidence of increased osteosarcoma (bone cancer) and osteoma (noncancerous bone tumors).87, 88  Additionally, there is also a possibility that fluoride ingestion might increase kidney and bladder cancer rates based on the tendency for hydrogen fluoride, a caustic and potentially toxic substance, to form under the acid conditions found in urine.89 This is another area where more research needs to be conducted.

The Fluoride Used for Water Fluoridation Comes from a Hazardous Waste Byproduct

While Florida is known as the Sunshine State, from a geological and economic perspective, it could just as accurately be known as the “Phosphate State”. The so-called “Bone Valley” of central Florida contains some of the largest phosphate deposits in the world, which supply global agriculture with one of its most important commodities: synthetic fertilizer. 

In the process, the phosphate mining industry creates highly toxic hydrogen fluoride gases that are by-products of fertilizer production. Before the 1970s, these pollutants were vented into the atmosphere and gave central Florida some of the most noxious air pollution in the country. During the 1960s, however, complaints by the public eventually forced reluctant manufacturers to invest in pollution abatement scrubbers that converted toxic vapors into fluorosilicic acid (FSA), a dangerous but more containable liquid waste. The U.S. National Institute for Occupational Safety and Health (OSHA) cautions that FSA, an inorganic fluoride compound, has dire health consequences for any worker who comes in contact with it. Breathing its fumes causes severe lung damage or death and an accidental splash on bare skin will lead to burning and excruciating pain. Fortunately, it can be contained in high-density polyethylene storage tanks.

It is in such tanks that fluorosilicic acid has for the past half century been transported from Florida and other fertilizer factories in the U.S. to water reservoirs throughout the United States. Once there, it is drip-fed into drinking water for the alleged purpose of preventing tooth decay. This of course has its fingerprint all over economic incentives for disposing of hazardous waste. It is mutually beneficial. Without the phosphate industry’s waste, water fluoridation would be prohibitively expensive, and without fluoridation, the phosphate industry would be stuck with an expensive waste disposal problem. 

Many would be surprised to learn that, unlike the pharmaceutical-grade fluoride in their toothpaste, the fluoride in their water is an untreated industrial waste product, one that contains trace elements of arsenic and lead. 

Rising Opposition to Fluoridation

Opposition to water fluoridation has been growing worldwide, emphasizing the potential and serious risk of toxicity. Fluoridated water is the largest source of concern, and most water filters are not adequate for removing fluoride. Instead, look to reverse osmosis water purification systems. Thus, it is also best to use non-fluoride toothpaste. For more information about the hazards of fluoride visit Fluoride Action Network (https://fluoridealert.org/).

Conclusion

Fluoride is a cellular toxin and over time accumulates in the body and can lead to the inhibition of numerous critical proteins, a release of free radicals, disruption of metal homeostasis, a disruption in pH (acidification of the extracellular matrix), and tissue-organ, and glandular damage. Fluoride enters the body mostly from municipal water sources that have been fluoridated and beverages that use public water in their manufacturing process. Dental treatments and toothpaste also account for some contamination as well. The degree of toxicity is determined by how much fluoride a person consumes during their lifetime, as well as their genomic profile’s ability to detoxify this element. 

Many non-governmental organizations have formed to oppose any fluoridation efforts in Europe and to encourage communities in the U.S. and Canada to stop this practice.  One such group is the Fluoride Action Network (https://fluoridealert.org/). Thus, fluoridation remains a contentious issue, and this controversy is likely to continue for some time. The controversy centers on quantifying a threshold that separates “safe from unsafe” doses and whether the alleged benefits of fluoride ingestion outweigh the potential adverse health effects. It is becoming clear that there is little or no benefit from adding fluoride to public water and the health risks are greater in children.

Several studies have demonstrated that dietary fluoride ingestion affects the intelligence of children, lowering the intelligence quotient (IQ). The accumulation of fluoride in combination with aluminum can cross the blood-brain barrier and potentially participate in neurodegenerative diseases such as Parkinson’s disease, dementia, and Alzheimer’s disease. Studies of both laboratory animals and human populations also indicate that fluoride can adversely affect normal endocrine function and response, particularly the thyroid gland resulting in hypothyroidism and pineal resulting in calcification. A variety of gastrointestinal effects, including nausea, vomiting, diarrhea, and abdominal pain, have also been reported in cases of acute fluoride toxicity. In severe acute cases, this may progress to renal and cardiac dysfunction, coma, and ultimately death. Children are most sensitive to fluoride and as little as 8.4 mg/kg may produce symptoms. Bear in mind it is accumulative in the body.

Chronic fluoride toxicity is usually caused by high fluoride concentrations in drinking water or the use of fluoride supplements. Chronic ingestion of high doses leads to dental fluorosis, a cosmetic disorder where the teeth become mottled. In more severe cases, it leads to skeletal fluorosis, in which bone is radiologically dense but fragile. Fractures can occur, and there may be calcification of ligaments and tendons, leading to reduced joint mobility. The syndrome also may include extensive calcification of ligaments and cartilage, as well as the bony outgrowths of osteophytes and exostoses.

The debate today is not about fluoride’s acute toxicity, as that is well established. The controversy surrounds chronic toxicity (i.e., the dose of fluoride that if regularly consumed and deposited in the body over an extended period can cause adverse effects). Scientists and a growing number of health professionals concluded that water fluoridation is an unreasonable risk and must be stopped before it is too late.

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