sentence: Selenium is a trace element in the human body.
sentences_after: Humans need very small amounts of selenium. Only about 50-200 micrograms are needed. Selenium can be toxic if more than 400 micrograms are taken. Once there was coal that had a large amount of selenium in it. People were getting selenium poisoning from the coal.
concept_name: selenium
headings: Selenium Uses In the human body
categories: Chemical elements Nonmetals