Assertion: mercury's potential | /r/HasProperty | documented in the 1950
Facets:
value: well
type: DEGREE
Source sentences:
text: Although its potential for toxicity in highly contaminated areas such as Minamata Bay, Japan, in the 1950's and 1960's, is well documented, research has shown that mercury can be a threat to the health of people and wildlife in many environments that are not obviously polluted.