The summing of fluoride exposures

In our industrial era, especially the last two decades, human beings have been increasingly exposed to fluoride from multiple sources. In view of the narrow margin between tolerance and toxicity from fluoride accumulation, consideration should be given to the number and sumof exposures: (1) to airborne fluoride of industrial origin, and its effects on soil and food plants, including biological conversion of inorganic fluorides to more toxic organic fluorides; (2) to water‐borne fluorides, including water fluoridation and its effects on foods and beverages, as well as fluoric wastes discharged into waters; (3) to other often‐unsuspected sources notably fluoride‐containing fertilizers, pesticides and some Pharmaceuticals. An attempt has been made merely to indicate inter‐relations and variables of the complex fluoride cycle. Consequences of human exposure depend not only on duration and intensity, as well as the type of fluoride, but nutritional status is significant. Immature organisms and certain metabolic defectives are at risk from fluoride accumulation, and biochemical idiosyncracy seems to play an important role. Careful study is needed of the upward shift in environmental fluoride and an effort should be made to appraise total exposures from all sources in order to protect the environment and people of varying vulnerability.