Fluoride Action Network


This article reviews an important phase of the debate concerning a striking association between artificial fluoridation of public water supplies and increased crude cancer death rates in large central cities of the United States from 1940 through 1968. The authors believe that this association reveals a causal relationship between water fluoridation and human cancer. Critics insist that the association is explained by demographic changes in the two groups of central cities which have been compared. The authors evaluate the major papers of these critics, and show that, if all available and pertinent data are standardized by the indirect method for age, race, and sex, the association between fluoridation and cancer remains substantially intact, but somewhat reduced. Attention is also given to a recent suggestion that the association can be explained by changes in population sizes of the twenty cities observed. Analysis of this proposal reveals that, in the cities considered during the period observed, changes in population size were essentially an inverse index of population aging, and yielded adjustments parallel to those of age, race, and sex. It is concluded that artificial fluoridation appears to cause or induce about 20-30 excess cancer deaths for every 100,000 persons exposed per year after about 15-20 years.