New research of bone cancer figures has shown a 40% elevated rate in Republic of Ireland (fluoridated) compared to Northern Ireland (unfluoridated).(1) The bone cancer in question called osteosarcoma is one of the most prevalent cancers in young males, aged 9-20. There are both animal and human studies linking osteosarcoma and water fluoridation/fluoride.(2,3)
One study in 1992, in the United States, indicated that in three counties of New Jersey there was nearly 7 times the osteosarcoma rate in young males in the fluoridated communities compared to the non-fluoridated communities.(4)
The research figures provided by the National Cancer Registry in Cork and Northern Ireland Cancer Registry (DHSSPS) did not indicate a statistically significant correlation but are noteworthy nonetheless. Moreover, Northern Ireland recently refused to dose their drinking water with chemical fluoride. In 1996, 25 out of 26 councils voted against water fluoridation because of concerns over fluoride health damage.
The legislation, which permits fluoridation in this country, the Health (Fluoridation of Water Supplies) Act 1960, requires the Minister of Health to carry our health studies into the effects of nearly forty years of this mass-medication.(5) This research has never been done.(6)
Dr. Don Mac Auley, dental advisor to Fluoride Free Water, commented, "another fluoride health alert is screaming but when will the Minister of Health start listening? When will the Minister fulfil his duty and carry out the health studies required by law. It is outrageous that there are still no plans for health studies, despite the new National Health Research Strategy, which "proposes a thriving research culture".(7) Instead, Minister Martin has delegated his responsibilities to a pro-fluoride sham of a forum,(8) which cannot even get its act together to report on time".
Dr. Andrew Rynne, a Co. Kildare G.P, also affirmed his concern for his patients, "[f]luoride is a known carcinogen. Given enough of the stuff, our cancer rates may climb above those of countries that do not mainline their citizens in this way. Is there much quality and fairness in the continuation of a practice that might cause people to get cancer at an increased rate?"(9)
Dr. John Colquhoun, a New Zealand dentist and former advocate of fluoridation, changed his mind after extensive research on the subject.(10) In a recent interview, on the issue of bone cancer and fluoride, he posed the question, "How many cavities would have to be saved to justify the death of one young man from osteosarcoma?"(11)


1. Fluoride Free Water Press Release. 8/1/2002. SEE BELOW.

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

3. Mihashi M, Tsutsui T. Clastogenic activity of sodium fluoride to rat vertebral body-derived cells in culture. Mutat Res 1996 May;368(1):7-13.

4. Cohn PD. A brief report on the association of drinking water fluoridation and the incidence of osteosarcoma among young males . N J Dept of Health, Trenton, New Jersey. Nov 8, 1992. See

5. Health (fluoridation of water supplies) Act 1960. Section 6.

6. Dr. Gerard Gavin, Chief Dental Officer, Dept. of Health, presentation to the Dail Committee on Health and Children. 20/7/2000. Transcript of proceedings

7. National Health Research Strategy key elements. Quality and fairness: a health system for you. Department of Health. 2001 pg. 92. See

8. Irish Medical News. 13/8/01.

9. Irish Medical News. 14/12/2001.

10. Why I changed my mind about fluroidation. Chicago Press. Available at

11. Dr. John Colquhoun. Video-taped interview, Auckland, NZ, May 1998. GG Video, 82 Judson Street, Canton, NY 13617.

Comparison of Rep.of Ireland and N.Ireland figures for Osteosarcoma. Rep.of Ireland figures:Piaras O'Lorcain,Data Analyst,National Cancer Registry,Elm Court,
Boreenmanna Road,Cork.
Tel 021-4318014 Fax 021 4318016
Web: N.Ireland figures: Stephen Sharp, N Ireland Cancer Registry (NICR), DHSS.
Relative rate of osteosarcoma in Republic of Ireland vs. Northern Ireland for the years 1994-1997 (combined), with approximate 95% confidence intervals:
crude analysis (no adjustments): 1.6 (0.9, 3.0) adjusted analysis (age and sex): 1.4 (0.8, 2.6)

According to these calculations, the osteosarcoma rate in the Republic was about 40% elevated compared to Northern Ireland but the results were not very precise. Adjustment for age and sex did not make much difference.
In other words, the best (central) estimate indicates a somewhat elevated rate in the Republic relative to Northern Ireland. The results are compatible with no difference (a relative rate of one), but they are also compatible with higher values.
Some analysts might be tempted to conclude that since the 95% confidence interval includes one, the results are not "real" because they are not "statistically significant." This interpretation is not good epidemiologic practice. See, for example: Poole, C. (1987). "Beyond the Confidence Interval." American J Public Health 77:195-199. Rothman and Greenland (1998). Modern Epidemiology (2nd edition), especially Chapter 12. Rothman (1986). Modern Epidemiology (1st edition)
These calculation could be improved, for example, by using populations figures for each year rather than just 1999.

Methods: I used 1999 population data for the denominators of the rates. The adjusted analysis is a standardized rate ratio.

Data sources: ROI osteosarcoma data by age, gender and year--excel file from Piaras O'Lorcain (10/25/01) NI osteosarcoma data--your email from 9/29/01 1999 population data--"Ireland North and South: A Statistical Profile, 2000 edition."
Note: The age/gender/year data for ROI do not precisely match the age/year data in your email of 9/29/01 in an excel file from Piaras O'Lorcain. The reason for this discrepancy is unclear.
Tom Webster, D.Sc.
Assistant Professor
Department of Environmental Health (T2E)
Boston University School of Public Health
715 Albany Street
Boston, MA 02118-2526, USA

tel: (617)638-4641
fax: (617)638-4857