Assertion: comfrey's leaf | /r/MadeOf | 0.026% pyrrolizidine
Facets:
value: in 1986
type: TEMPORAL
value: in one trial
type: LOCATION
value: on a dry weight basis
type: OTHER
Source sentences:
text: In one trial, in 1986, immature leaves contained 0.026% pyrrolizidine, on a dry weight basis.