Assertion: lead pencil's lead | /r/CapableOf | prevent the incorporation of iron
Facets:
value: into protoporphyrin ix
type: OTHER
Source sentences:
text: In the human body, lead inhibits porphobilinogen synthase and ferrochelatase, preventing both porphobilinogen formation and the incorporation of iron into protoporphyrin IX, the final step in heme synthesis.