Fluoridation and horses – another myth

By Ken Perrott 10/06/2015

Readers following the fluoridation issue have probably come across claims fluoridated water can poison horses. This is just another case of scaremongering by anti-fluoride propagandists – but what is it based on?

The claims go back to Cathy Justus, a horse owner from Pagosa Springs, Colorado. She lost eight horses and four dogs and blames it on their consumption of fluoridated water – which she describes as a “virulent cumulative toxin.” She also claims to “have the sad distinction of owning the first horses to ever be diagnosed with “chronic fluoride poisoning” from artificially fluoridated municipal water.”

Of course, her claim to owning the first horses diagnosed with poisoning by fluoridated water sets off alarm bells straight away. What happened to all the other horses which have consumed fluoridated water? And how could her diagnosis be so different?

What to the experts say?

According to Associate Professor Cynthia Gaskill, toxicology section chief at the Veterinary Diagnostic Laboratory at the University of Kentucky (see Expert discusses fluoridated water and horses in Horsetalk.co.nz):

“A casual internet search of this topic can uncover alarming reports purporting fluoride poisoning in horses from fluoridated municipal water.

“These reports typically are published in non-peer reviewed sources and are missing important information necessary to confirm the diagnosis, to rule out exposure to other fluoride sources, and to eliminate other potential causes.

“A careful review of the peer-reviewed literature in reputable scientific journals showed no published reports documenting fluoride poisoning in horses due to ingestion of fluoridated public water.”

An expert with the Sonoma County Horse Council, Ted S Stashak, concluded in his article The Effects of Artificial Fluoridation of Water (AFW) on Horses:

“Evidence to date indicates that F concentrations allowable in US public water systems are well tolerated by horses and do not cause fluorosis. Supporting this, is a fact that many horses nationwide drink AFW as their major source of water and fluorosis is a  very rarely reported condition.”

Why is Cathy Justus so convinced?

It doesn’t take much background reading to see Cathy Justus may be suffering a bit of confirmation bias. In a long letter to the Baltimore Post Express in 2012 she describes her own beliefs and the symptoms of her animals (see Poisoned Horses: Fluoride debate continues). Have a read of at least some of it and you will get the idea.

Cathy is a dyed in the wool anti-fluoride propagandist. Her letter is full of all the “arguments” and relies on the usual anti-fluoride bibles like The case Against Fluoride, The Fluoride Deception, etc. The letter’s tone is typical of someone with these extreme views. So it comes as no surprise to find she is also Fluoride Action Network’s (FAN) National Spokesperson against Fluoride Poisoning in Animals.

She is convinced that her  animals’ problems were caused by fluoridated water (as are all the health problems humans currently have) and, in her own mind, that this is not observed by other horse owners just indicates their ignorance and brainwashing.

But wait, there’s more

Cath Justus searched around until she found a veterinary expert who agreed with her bias – in this case, Dr. Lennart Krook, Professor Emeritus, Cornell University. So this whole incident got into the “peer-reviewed” (?), “scientific” (?) literature. To be exact, 2 papers and an editorial in the journal Fluoride – which she describes as the “fluoride bible.” You can check them yourself:

  • Krook, L. P., & Justus, C. (2006). Fluoride poisoning of horses from artificially fluoridated drinking water. Fluoride, 39(March), 3–10.
  • Justus, C., & Krook, L. P. (2006). Allergy in horses from artificially fluoridated water. Fluoride, 39(June), 89–94.
  • Sauerheber, R. (2013). Racehorse breakdowns and artificially fluoridated water in Los Angeles. Fluoride, 46(December), 182–191.

As you might expect from that journal these papers are of poor quality – and, in particular, they present no evidence for the firm beliefs that fluoridated water was the cause of the problems described. Or their equally strong assertions that there is no possibility that feed contamination or other usual causes were absent. As Stashak says, these papers:

“are missing important information necessary to confirm that AFW alone was the cause for the signs of chronic fluorosis in these horses.”

A strongly held, motivated, anecdotal opinion is not evidence and would not be accepted as such by any self-respecting scientific journal. For the life of me, I cannot see how anyone could claim such papers are “peer-reviewed.”

All three authors are organisationally connected with the anti-fluoridation movement. Jutsus through here FAN position.  Krook through his membership of the anti-fluoride group Second Look‘s Advisory Board and his membership of the Editorial Board of Fluoride since 1990 and Associate Editor since 2003 (as described in his 2010 obituary of Fluoride).  Saueheber is part of James Deal’s (Attorney Deal) anti-fluoride Fluoride Class Action group.


This is just another example of the way anti-fluoride propagandists attempt to convert their biases into “facts.” They have produced multiple articles in the friendly “natural”/alternative health media, and even a video, to support this particular claim. Their tame “scientific” journal, Fluoride, has been dragged in to give academic credibility – and it is unlikely any reputable journal could have been used for this, given the lack of evidence.

In a rather pathetic footnote, Richard D Sauerheber, author of the editorial referred to, gives his institutional affiliation as University of California, San Diego, La Jolla, CA 92037, USA. He also did this in his one other published paper referred to in my post Calcium fluoride and the “soft” water anti-fluoridation myth. In our discussion there he admitted he does not work at that institution, although he did study there many years ago. This is the first time I have come across an author using their university of study as an institutional affiliation in this way. It is deceptive and aimed purely at attempting to claim credibility to himself and any article where he does this. I would be interested to know what officials at that university think of this practice.