Fluoride & Bone Cancer

by Dr. Paul Connett, Professor of Chemistry, St. Lawrence University.

(The following is an excerpt from Connett's essay "Fluoride: A Statement of Concern" - January 2000)

Another set of findings which has been outrageously downplayed in my view is a possible association between water fluoridation (or fluoride exposure) and osteosarcoma (bone cancer) in young males. Of particular interest in this matter is a little known comment which was made by an early reviewer of the medical examinations of the children studied during the Newburgh-Kingston fluoridation trial (36). This comment was picked up by the authors of a National Academy of Sciences report in 1977, and further amplified:

"There was an observation in the Kingston-Newburgh (Ast et al, 1956) study that was considered spurious and has never been followed up. There was a 13.5% incidence of cortical defects in bone in the fluoridated community but only 7.5% in the non-fluoridated community... Caffey (1955) noted that the age, sex, and anatomical distribution of these bone defects are `strikingly' similar to that of osteogenic sarcoma. While progression of cortical defects to malignancies has not been observed clinically, it would be important to have direct evidence that osteogenic sarcoma rates in males under 30 have not increased with fluoridation." (37).

Surely, if objective government scientists had been aware of this concern or prediction, they might have taken far more seriously the studies that followed. For example, in 1990 the National Toxicology Program (NTP) published the results of a 2-year study of rats and mice treated with fluoride in their drinking water performed by scientists at Battelle laboratories (38). Even though a peer review of this Battelle study removed some of the other cancers found (erroneously according to Dr. William Marcus at the US EPA) (39), it still showed a dose-related increase in osteosarcoma in the male but not the female rats. Rather than taking this result as a serious red flag, government scientists seemed to have done everything they could to downplay it. According to Dr. William Marcus, who was the senior scientist at US EPA's Office of Drinking Water in 1990, the NTP studies done by Battelle

"showed that there was an increased level of bone cancer and other kinds of cancer in the animals. When I got a hold of the contractor report and reviewed it very carefully, not only was it reporting cancers in the animals, [it was reporting] osteosarcomas, which bothered me a lot because I've been trying to produce osteosarcomas in animals for almost 20 years and the only luck I ever had was with an experiment in dogs and monkeys and the osteosarcomas took nearly the lifetime of the animals and we were using radium which specifically produces that in bones. And here we have a compound commonly available (fluoride) that did it in rats in two years or less. That was upsetting to begin with. Secondarily, in that same study, there were cancers of the liver that are very rare according to the board certified veterinary pathologist at the contractor, Battelle, and those really were very upsetting because they were hepatocholangiocarcinoma, a very rare, rare, liver cancer and when that occurs, something similar to that occurred with vinyl chloride in a far less well conducted study and it was determined that it was carcinogenic, highly carcinogenic. Then there were several other kinds of cancers found in the jaw and other places and I felt at the time that the report was very, very interesting. It showed that the levels of the fluoride that caused the cancers in the animals were actually lower than those levels seen in people who are ingesting lower amounts but for longer periods of time and that was very, very worrisome. It meant that the general population could be exposed to fluoride known to cause cancer in animals and have levels near the cancer being produced in the bones... I went to a meeting that was held in Research Triangle Park in April 1990, the latter part of April, in which the NTP was presenting their review of the study and I went with several colleagues of mine one of whom was a board certified veterinary pathologist who had originally reported hepatocholangiocarcinoma as a separate entity in rats and mice and I asked him if he would have an opportunity to look at the slides to see if that really was a tumor or the pathologist at Battelle had made an error and he told me after looking at the slide that in fact it was correct and at the meeting every one of the cancers that was reported by the contractor had been down-graded by the NTP. Now I've been in the toxicology business looking at studies of this nature for nearly 25 years and I've never seen that, never ever seen where every single endpoint that was a cancer endpoint had been down-graded. I'd seen one or two endpoints argued over, usually on a definition what is a cancer in that particular tissue but I've never seen every one of them down-graded. I found that very suspicious and I went to see an investigator in the Congress at the suggestion of my friend Bob Carton and this gentleman and his staff investigated very thoroughly and found out that the scientists at the NTP down at Research Triangle Park had been coerced to change their findings." (40)

Some said the results were equivocal. Others said the doses were so high that they weren't relevant, and yet it is standard toxicological practice to treat a small group of animals to a large dose of a toxicant if you are to have a statistical chance of observing any change in the small sample size. The alternative is to treat a very large number of animals to a lower dose, which is prohibitively expensive. The National Research Council (NRC) in a 1993 report (41) described the result as follows: "The equivocal result of osteosarcoma in male rats was not supported by results in females in the same study" (page 122). This is an extraordinary statement in the context of the concerns raised by the NAS in 1977 (see paragraph 25) because it is precisely the result the authors had feared. The NRC further downplayed the result based upon a study by Proctor and Gamble (42) (hardly a disinterested party in these matters) which hadn't found any osteosarcomas in their rat studies (they had found osteomas in mice, but they were considered not important because they were non-malignant). Dr. John Yiamouyiannis used the Freedom of Information Act to take a closer look at the P&G studies and found that they had found cancers in their rats as well as lesions which could lead to cancers (43).

A suspicious person might wonder if the US government was maneuvering around the Delaney Clause, which was operating at that time. This clause introduced by Congressman Delaney required that no chemical found to cause cancer in animal studies be added to food. Thus, if a link had been found between fluoride and cancer in these animal studies it would have scuttled the whole fluoridation program then and there.

In 1992, a report was published by the New Jersey Department of Health (44) which indicated that in three fluoridated counties in NJ, there was a seven-fold increase in osteosarcomas in young males, compared to non-fluoridated counties. There was no increase in the females. Again, this is precisely the result feared/anticipated by the NAS commentators in 1977.

In an earlier national survey under the SEER program (45) increases in osteosarcomas in young males were further correlated with fluoridation in two other states. However, a study in New York, published in 1991, had not found any increase they could relate to water fluoridation (46). Three other studies have failed to find a relationship between bone cancer rates and fluoridation. These are discussed by Dr. John Yiamouyiannis in an excellent review of the osteosarcoma data for the journal Fluoride (43). Dr. Yiamouyiannis has pursued the fluoride-cancer connection more thoroughly than any other scientist alive. For some, the positive and negative results on osteosarcoma incidence in fluoridated communities neatly cancel one another out. For me this is too serious an issue to be so lightly dismissed. In an interview I had with the late Dr. John Colquhoun he posed the question: "How many cavities would have to be saved to justify the death of one young man from osteosarcoma?".


36. Schlesinger, E.R., et al (1956). Newburgh-Kingston Caries-Fluorine Study XIII. Pediatric Findings After ten Years. Journal of the American Dental Association, 52.

37. National Academy of Sciences (1977). Drinking Water and Health. National Academy Press, Washington, DC., pp. 388-389.

38. National Toxicology Program [NTP] (1990). Toxicology and Carcinogenesis Studies of Sodium Fluoride in F344/N Rats and B6C3f1 Mice. Technical report Series No. 393. NIH Publ. No 91-2848. National Institute of Environmental Health Sciences, Research Triangle Park, N.C.

39. Marcus, W. (1990). Fluoride Conference to Review the NTP Draft Fluoride Report. Memorandum dated May 1, 1990, from Wm. L. Marcus, Senior Science Advisor Office of Drinking Water (ODW), US EPA to Alan B. Hais, Acting Director Criteria & Standards Division ODW, US EPA.

40. Natural Living with Gary Null. (Radio program on station WEVD (1050 AM) in New York City, tel: 212-799-1246). Broadcast March 10, 1995. Program #310. Interview between William Marcus and Gary Null. Complete audio tape available for $13.50 from 1-888-317-2346.

41. National Research Council (1993). Health Effects of Ingested Fluoride. National Academy Press, Washington, DC.

42. Proctor and Gamble study, cited in Ref. 32 but not referenced under this name. The study is probably that of Maurer, J.K. et al, (1990). Two Year Carcinogenicity Study of Sodium Fluoride in Rats. Journal, National Cancer Institute, 82, 1118-1126.

43. Yiamouyiannis (1993). Fluoridation and Cancer. The Biology and Epidemiology of Bone and Oral Cancer Related to Fluoridation. Fluoride, 26, 83-96.

44. Cohn, P.D. (1992). An Epidemiologic Report on Drinking Water and Fluoridation. New Jersey Department of Health, Trenton, NJ

45. Hoover, R.N. et al (1991). Fluoridation of Drinking Water and Subsequent Cancer Incidence and Mortality. In Review of Fluoride: Benefits and Risks, Report of the Ad Hoc Committee on Fluoride of the Committee to Coordinate Environmental Health and Related Programs. US Public Health Service, pp E1-E51.

46. Mahoney, M.C. et al (1991). Bone Cancer Incidence Rates in New York State: Time Trends and Fluoridated Drinking Water. American Journal Public Health, 81, 475-479.