Ultratrace element

In biochemistry, an ultratrace element is a chemical element that normally comprises less than one microgram per gram of a given organism (i.e. less than 0.0001% by weight), but which plays a significant role in its metabolism.

Possible ultratrace elements in humans include boron, silicon, nickel, vanadiumJ. Mann & A. S. Truswell (editors). Essentials of Human Nutrition (3rd edition, 2007). Oxford: Oxford University Press and cobalt.{{cite book|first1=Kazuhiro|last1=Yamada|editor=Astrid Sigel|editor2=Helmut Sigel|editor3=Roland K. O. Sigel|title=Interrelations between Essential Metal Ions and Human Diseases|series=Metal Ions in Life Sciences|volume=13|date=2013|publisher=Springer|pages=295–320|chapter=Chapter 9. Cobalt: Its Role in Health and Disease|doi=10.1007/978-94-007-7500-8_9|pmid=24470095|isbn=978-94-007-7499-5 }} Other possible ultratrace elements in other organisms include bromine, cadmium, fluorine, lead, lithium, and tin.Nielsen, Forrest H., Ultratrace Elements in Nutrition, Annual Review of Nutrition

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