Assertion: fluoride | /r/AtLocation | u.s. drinking water
Facets:
value: by ’60s
type: TEMPORAL
value: by the 1950s
type: TEMPORAL
Source sentences:
text: By the 1950s and ’60s, when the practice of releasing fluoride vapors into the air was reined in due to the introduction of air pollution technology, fluoride had already been added to U.S. drinking water.
text: By the 1950s and ’60s, when the practice of releasing fluoride vapors into the air was reined in due to the introduction of air pollution technology, fluoride had already been added to U.S. drinking water.