Assertion: lead's use | /r/HasProperty | discontinued
Facets:
value: largely
type: DEGREE
Source sentences:
text: However, that use has been largely discontinued due to its toxicity and poor stability.
text: The organic lead compound tetraethyl lead, Pb(C 2 H 5 ) 4 , was widely used as a gasoline additive to prevent knock in automobile until concern about lead toxicity caused that use to be discontinued.