Assertion: selenium's amount | /r/HasProperty | required
Facets:
value: in order to become toxic
type: PURPOSE
Source sentences:
text: But humans have been affected too- mainly in areas with high selenium levels in the WATER, as most humans don't eat the large amount of selenium containing foods that would be required in order to become toxic from foods grown in high selenium areas.
text: Only small amounts of selenium are required for the body to function properly.
text: Selenium is essential for human health, but since only tiny amounts are required, it is classified as a trace mineral.