Fluoridation and cancer mortality in Anglesey.

Mortality in Anglesey from cancer (all sites), cancer of trachea, bronchus, and lung, cancer of stomach, and cancer of all other sites has been compared with mortality in England and Wales at two periods; 1949-53 (before fluoridation) and 1979-83 (after 20 years and more of fluoridation). No evidence has been found to support the hypothesis that water fluoridation affects cancer mortality.