Assertion: comfrey's effect | /r/AtLocation | various test systems
Facets:
value: for the symphytum-pyrrolizidine
type: OTHER
value: as a precaution
type: PURPOSE
Source sentences:
text: Sincea mutagenic effect could be observed in various test systems for the Symphytum-Pyrrolizidine, as a precaution, comfrey preparations may only be applied to intact skin.