Editing Trace element (section)

==Types==
{{Main|Mineral (nutrient)}}
The two types of trace element in [[biochemistry]] are classed as essential or non-essential.

===Essential trace elements===
An essential trace element is a [[dietary element]], a [[Mineral (nutrient)|mineral]] that is only needed in minute quantities for the proper growth, development, and physiology of the organism.<ref>{{cite book |last1=Bowen |first1=Humphrey John Moule |author-link1=H. J. M. Bowen |title=Trace elements in biochemistry |date=1966 |publisher=[[Academic Press]] |isbn=9780121209506 |url=https://books.google.com/books?id=AH2T3X0enHkC}}</ref> The essential trace elements are those that are required to perform vital metabolic activities in organisms.<ref name="Soto-Jiménez M.F.">{{cite journal |last1=Soto-Jiménez |first1=Martin |title=Trace element trophic transfer in aquatic food webs |journal=Hidrobiológica |date=December 2011 |volume=21 |issue=3 |pages=239–248 |issn=0188-8897 |url=http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S0188-88972011000300003 |access-date=5 November 2018}}</ref> Essential trace elements in [[human nutrition]], and other animals include [[iron]] (Fe) (hemoglobin), [[copper]] (Cu) ([[respiratory pigment]]s), [[cobalt]] (Co) ([[Vitamin B12]]), [[iodine]] (I), [[manganese]] (Mn), [[chlorine]] (Cl), [[molybdenum]] (Mo), [[selenium]] (Se) and [[zinc]] (Zn) (enzymes).<ref name="Soto-Jiménez M.F." /><ref>{{Cite book|title=Hole's Human Anatomy Fourteenth Edition|last=Shier, Butler, Lewis|first=David, Jackie, Ricki|publisher=McGraw Hill Education|year=2016|isbn=978-0-07-802429-0|location=New York|pages=59}}</ref> Although they are essential, they become toxic at high concentrations.<ref name="Jomova">{{cite journal |vauthors=Jomova K, Makova M, Alomar SY, Alwasel SH, Nepovimova E, Kuca K, Rhodes CJ, Valko M |title=Essential metals in health and disease |journal=Chem Biol Interact |volume=367 |issue= |pages=110173 |date=November 2022 |pmid=36152810 |doi=10.1016/j.cbi.2022.110173 |url=|doi-access=free |bibcode=2022CBI...36710173J }}</ref>

===Non-essential trace elements===
Non-essential trace elements include [[silver]] (Ag), [[cadmium]] (Cd), [[mercury (element)|mercury]] (Hg), and [[lead]] (Pb). They have no known biological function in mammals, with toxic effects even at low concentration.<ref name="Soto-Jiménez M.F." />

The structural components of cells and tissues that are required in the diet in gram quantities daily are known as ''bulk elements''.<ref>{{Cite web |title=Essential Elements for Life |url=https://saylordotorg.github.io/text_general-chemistry-principles-patterns-and-applications-v1.0/s05-08-essential-elements-for-life.html |access-date=2023-02-13 |website=saylordotorg.github.io}}</ref>