1. Fluoridation chemicals are byproducts of industrial fertilizer production…Really
Hard as it is to believe, the three chemicals used to “fluoridate” drinking water are all industrial byproducts of fertilizer production. This is admitted even by leading fluoridation promoters such as the U.S. Center for Disease Control and highlights why there is good reason to research the facts about water fluoridation despite claims that fluoridation chemicals don’t pose any risks.
As the CDC’s chief fluoridation engineer explained:
“All of the fluoride chemicals used in the U.S. for water fluoridation, sodium fluoride, sodium fluorosilicate, and fluorosilicic acid, are byproducts of the phosphate fertilizer industry.” 
The National Research Council of the National Academy of Sciences similarly reports that:
“the most commonly used [drinking water] additives are silicofluorides, not the fluoride salts used in dental products (such as sodium fluoride and stannous fluoride). Silicofluorides are one of the by-products from the manufacture of phosphate fertilizers.” 
Learn more in this review and compilation of original documents regarding the industrial origin of fluoridation chemicals and the presence of toxics, such as arsenic and lead, in these chemicals.
2. Significant new scientific evidence shows that the health risks of fluoridation are substantial
As is true for many chemicals once declared “safe,” there is a fast-growing body of scientific literature supporting that there are real risks related to consuming fluoridation chemicals in drinking water.
For example, in 2015 the federal government reduced the maximum allowable fluoride concentrations in drinking water by 40%, its first change in 50 years.  The reduction came after an extensive study, Fluoride in Drinking Water, published by an expert panel of the National Research Council of the National Academy of Sciences (“National Academy Study”) and data showing 41% of U.S. children were receiving too much fluoride and had visible signs of excessive fluoride intake – ie. “fluorosis.”  
The National Academy Study also reviewed substantial scientific evidence raising significant questions about the link between fluoride exposure and potential health effects—ranging from neurologic impacts to thyroid damage.  View key excerpts from the National Academy Study.
In 2014, Harvard researchers named fluoride as one of the top developmental neurotoxins impacting children’s brain development in the prestigious medical journal The Lancet. 
The report followed another large-scale meta-study showing that elevated fluoride levels in drinking water were correlated with decreased childhood IQ. 
These and other studies have led a significant number of water quality experts, such as U.S. EPA Union of Professionals  and the Oregon Department of Environmental Quality’s Employee Union , to formally oppose the practice of water fluoridation.
To review additional significant scientific studies regarding the risks of water fluoridation, visit FluorideAlert.org.
3. Fluoride is a drug that every individual should have the right to choose for themselves whether or not to consume
Fluoride meets every legal and medical definition of a drug (“intended to treat, mitigate or cure disease” – ie. dental cavities) and is the only drug that is added to the water supply with the stated goal of affecting human health.
This raises serious ethical issues, as many people either do not want fluoridation chemicals in their water or cannot tolerate fluoridation chemicals in their water because of health conditions such as hyperthyroidism or diabetes. Typical water filters will not work to remove fluoridation chemicals.
Because people drink very different levels of water (athletes or construction workers, for example, consume much more water than a typical office worker) water fluoridation means people can get widely differing fluoride exposures from drinking the same water source.The 2006 National Academy of Sciences report, for example, found infants who consumed formula mixed with fluoridated water ingested fluoride levels far in excess of the maximum recommended levels.
This was one of the reasons the federal government reduced maximum water fluoridation levels by 40% in 2015.
Even with this reduction, fluoridation promoters at the CDC admit that “if your child is only consuming infant formula mixed with fluoridated water, there may be an increased chance for mild dental fluorosis” and recommends sometimes using fluoride-free bottled water instead of tap water for mixing infant formula. 
But buying bottled water or installing very expensive water filtration systems that can remove fluoride are not options for low-income families that have no practical way to avoid drinking fluoridation chemicals if they are added to their drinking water.
4. There are far more effective alternatives to promoting kids’ dental health
The way fluoridation promoters talk about fluoridation as one of the world’s “Top 10 Public Health Benefits” you would think its benefits were well established and substantial.
But scratch the surface and the reality is far different. For decades, water fluoridation was promoted with the argument that swallowing fluoride provided a “systemic benefit” and that fluoride would concentrate in teeth and be excreted through salivary glands.
But by 2001, this theory was rejected even by fluoridation supporters like the CDC, after scientific studies found fluoride did not work systemically, only topically.
There is not a single double-blind study (the modern standard for showing scientific effectiveness) showing that fluoridated drinking water reduces cavities.
The epidemiological studies that supporters point to as supporting fluoridation—at best— show about a half cavity difference between childhood cavity rates in communities that are fluoridated and communities that are not. 
While fluoridation supporters use statistical tricks to inflate the importance of this difference, it is telling that the study they have long relied on as the key epidemiological evidence supporting the benefits of water fluoridation shows just a half cavity difference.
This is consistent with the fact that cavity rates in fluoridated and un-fluoridated countries have reduced at about the same rate since the 1950’s.
While fluoridation promoters continue to push the controversial addition of fluoridation chemicals to drinking water, there are important steps that we can all agree on to promote better oral health for children, such as increased access to care, increased preventative care, encouraging better nutrition, in-school dental screenings and allowing dental hygienists to do certain treatments on children’s teeth.
5. Fluoridation Chemicals Contain Arsenic, Lead and Other Toxics
Again, it's hard to believe, but given their origin as industrial byproducts, fluoridation chemicals are well-documented to contain contaminants such as arsenic and lead that have known human health risks.
Even the CDC openly cites to data from the National Sanitation Foundation (NSF) which admits that 43% of fluoridation chemicals test positive for arsenic. 
The maximum level of arsenic documented was 0.6 ppb which is about 6% of EPA’s Maximum Contaminant Level (the legal limit) for arsenic, but which exceeds EPA’s health-based Maximum Contaminant Level Goal for arsenic, which is zero. 
Fluoridation promoters typically dismiss the levels of arsenic, lead and other toxics that are added to drinking water when it is fluoridated as “too low to matter.”
But this ignores the reality that we should not be knowingly adding more toxics to our drinking water, but instead, should be doing everything possible to reduce our exposure, especially in our drinking water.