Fluoridated drinking water and the occurrence of cancer.

A recent report by the National Health Federation, a private agency, related cancer mortality patterns in the United States to fluoridation of water supplies, triggering much public health concern and some political response. To clarify the issues raised, we studied cancer mortality and incidence statistics for U.S. counties, 1950-69. No trends could be ascribed to the consumption of water that is artificially or naturally fluoridated.