$38 allegedly "saved" for
By Coert OlmstedMoose Mountain, Alaska,
Since I became involved with the community water supply fluoridation (CWSF) issue about two and a half years ago, I have frequently encountered a PR statistic claiming that for every dollar spent on CWSF there are $38 saved on avoided dental treatment costs. Tracking down the origin of this number, I find that the estimate was computed by a CDC group working on promoting CWSF as one of the 10 greatest accomplishments of 20th century public health in the USA.
I Googled the string 'fluoridation $38' and got about 111,000 hits, including one which led me to the following journal article:
Griffin SO, Jones K, Tomar SL. 2001. An economic evaluation of community water fluoridation. J Public Health Dent 61(2):78-86. Abstract at http://www.ncbi.nlm.nih.gov/pubmed/11474918?itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum&ordinalpos=2
The third author, Scott L. Tomar, identifies himself as a professor at the University of Florida College of Dentistry and president of the American Association of Public Health Dentistry. He was kind enough to email me a .pdf of the above paper. What follows is my brief review and critique.
That $38 number is computed as the quotient of $19.12 avoided in annual dental costs per person ( aged 6 to 65 in a community of over 20,000 population) by the $0.50 annual per capita expense of putting fluoride in that community's water supply at 1 ppm.
The expense and savings numbers are the best case examples from their data. Smaller communities had lower savings and higher costs. The percentage of the general population to which the $38 estimate applies is not given.
The "cost of disease averted and productivity losses" is counted only for dental caries and the "cost of resources" to treat affected dental surfaces. The "program cost" of fluoridation is the fixed expense of installation, with equipment cost depreciated over 15 years, plus the annual expenses of chemicals, labor and maintenance. This Program Cost is derived from 44 communities in Florida, the state with the most concentrated phosphate extraction industry and therefore the most abundant and nearby source of fluorosilicates.
Explicitly not counted are the "political costs associated with the passage of a water fluoridation referendum and overhead such as electricity, insurance and shared space."
Further cost exclusions are of any externalities associated with harmful side effects of fluoridation. In fact the authors justify ignoring these external costs because "adverse effects resulting from water fluoridation exposure are negligible." This is all the further they investigate possible negative side effects. A quantitative measure of how small is "negligible" is not given, nor is any reference to scholarly research on the subject provided. The only citation (#14) is to an unpublished internal US Public Health Service report: "US Department of Health and Human Services. Review of fluoride benefits and risks. Report of the ad hoc subcommitee on fluoride of the Committee to Coordinate Environmental Health and Related Programs. Washington, DC. US Public Health Service, 1991."
There is no consideration whatsoever given to external costs associated with control and cleanup of accidental spills of silicofluorides nor health and administrative costs of responding to accidental overfeeds of fluoride into community water systems.
Also unmentioned are the very significant costs of cosmetic and surficial dental treatment for tooth damage due to dental fluorosis. It is an axiom of the pro-fluoridation community that dental fluorosis is primarily a "merely cosmetic" effect. No dental research is cited to justify this assumption, nor is any scientific source or argument advanced in its favor. It is, in fact, a policy axiom settled upon long ago by unidentified authorities within the public health professional sector. In my experience, this kind of information is called "folklore" by scholars and occurs at many levels, even in advanced applied mathematics.
Thus it is clear that Griffin, Jones and Tomar's secondary research is a tightly narrow examination of the strictly microeconomic effects of CWSF over selected sample communities. Like most industry oriented economic analysis, it examines as little data as possible which will still provide a computable cost-benefit number. That unqualified number is then cited as widely as possible as the definitive result evaluating the benefit of the public health intervention policy being justified.
Even on its face, the $38 figure invites question. Sure a 38 fold return on investment is a fabulous payback in any economic system and if the external costs were not so potentially great nor so egregiously disregarded then CWSF would be the no-brainer policy that is so vigorously promoted by industry, public health agencies and taught as gospel in dental, medical and public health schools.
But lacking here is the comparison of $38 with the annual per capita cost of responsible dental health care. In this cost accounting, there should be included, not just regular checkups and hygienic treatment, but education, promotion and subsidy for proper and regular home care. Preventive home dental care is known by experts and common sense to be the most important factor in maintaining general dental health. What is the cost to the public and to individuals for this basic service? How does it compare with the CDC (or even the complete) computed cost of CWSF? However, research like this is not commonly promoted by public health agencies.
In a conversation with a physician I know well, I asked about his assessment of the gain from CWSF, citing the 2006 Bassin study which shows a significant increase in osteosarcoma in communities which practice CWSF. He suggested that the increased cancer death rate should be compared with the reduced rate, due to CWSF, of death from tooth abscesses. If more people are saved from death by tooth abscess than die from CWSF induced cancer, he opined, then CWSF is good policy.
I was nonplussed by the simplicity of his argument, and the narrow vision of health care that it exemplified. Basing public health intervention policy on a juggling of simplistic calculations of mortality and morbidity seems to miss the point. I see no reason we cannot enjoy both worlds - we eliminate the cancer deaths entirely by discontinuing CWSF. Then we recover more than the deficit in dental health benefit from CWSF by providing access to and promoting adequate and responsible levels of dental health care to all citizens. All the calculated deaths are avoided and net improvement in dental health is optimal. The main impediment to such a sane, rational policy is political ideology and a faith based adherence to a failed dogmatic bureaucratic orthodoxy.