Editing Manganese (section)

==Exposure==
===In water===
Waterborne manganese has a greater [[bioavailability]] than dietary manganese. According to results from a 2010 study,<ref name="Bouchard 138–143">{{cite journal|doi=10.1289/ehp.1002321 |volume=119|pages=138–143|pmid=20855239 |issue=1 |pmc=3018493|year=2011 |last1=Bouchard |first1=M. F |title=Intellectual impairment in school-age children exposed to manganese from drinking water |journal=Environmental Health Perspectives |last2=Sauvé |first2=S |last3=Barbeau |first3=B |last4=Legrand |first4=M |last5=Bouffard |first5=T |last6=Limoges |first6=E |last7=Bellinger |first7=D. C |last8=Mergler |first8=D |bibcode=2011EnvHP.119..138B }}</ref> higher levels of exposure to manganese in [[drinking water]] are associated with increased [[intellectual impairment]] and reduced [[intelligence quotient]]s in school-age children. It is hypothesized that long-term exposure due to inhaling the naturally occurring manganese in shower water puts up to 8.7&nbsp;million Americans at risk.<ref>{{cite journal|doi=10.1081/CLT-100102427|pmid=10382563|title=Manganese|date=1999 |author=Barceloux, Donald |journal=Clinical Toxicology|volume=37|last2=Barceloux|first2=Donald|issue=2|pages=293–307}}</ref> However, data indicates that the human body can recover from certain adverse effects of overexposure to manganese if the exposure is stopped and the body can clear the excess.<ref>{{cite journal|pmid=8143974 |year=1994 |last1=Devenyi |first1=A. G |title=Dystonia, hyperintense basal ganglia, and high whole blood manganese levels in Alagille's syndrome |journal=Gastroenterology |volume=106 |issue=4 |pages=1068–71 |last2=Barron |first2=T. F |last3=Mamourian |first3=A. C |doi=10.1016/0016-5085(94)90769-2|s2cid=2711273 }}</ref>

Mn levels can increase in seawater when hypoxic periods occur.<ref>{{Cite journal|last1=Hernroth|first1=Bodil|last2=Krång|first2=Anna-Sara|last3=Baden|first3=Susanne|date=February 2015|title=Bacteriostatic suppression in Norway lobster (Nephrops norvegicus) exposed to manganese or hypoxia under pressure of ocean acidification|url=http://dx.doi.org/10.1016/j.aquatox.2014.11.025|journal=Aquatic Toxicology|volume=159|pages=217–224|doi=10.1016/j.aquatox.2014.11.025|pmid=25553539|bibcode=2015AqTox.159..217H |issn=0166-445X}}</ref> Since 1990 there have been reports of Mn accumulation in marine organisms including fish, crustaceans, mollusks, and echinoderms. Specific tissues are targets in different species, including the gills, brain, blood, kidney, and liver/[[hepatopancreas]]. Physiological effects have been reported in these species. Mn can affect the renewal of [[immunocyte]]s and their functionality, such as [[phagocytosis]] and activation of [[Prophenoloxidase|pro-phenoloxidase]], suppressing the organisms' immune systems. This causes the organisms to be more susceptible to infections. As climate change occurs, pathogen distributions increase, and in order for organisms to survive and defend themselves against these pathogens, they need a healthy, strong immune system. If their systems are compromised from high Mn levels, they will not be able to fight off these pathogens and die.<ref name="Hernroth-2020" />

===Gasoline===
[[File:Methylcyclopentadienyl manganese tricarbonyl.tif|thumb|upright|Molecular model of [[methylcyclopentadienyl manganese tricarbonyl]] (MMT)]]
[[Methylcyclopentadienyl manganese tricarbonyl]] (MMT) is an additive developed to replace lead compounds for gasolines to improve the [[octane rating]].  MMT is used only in a few countries. When exposed to the environment, fuels containing methylcyclopentadienyl manganese tricarbonyl degrade, releasing manganese into water and soils.<ref>{{cite journal |author1=Arthur W. Garrison |author2=N. Lee Wolfe |author3=Robert R. Swank Jr. |author4=Mark G. Cipollone |title=Environmental fate of methylcyclopentadienyl manganese tricarbonyl |journal=Environmental Toxicology and Chemistry |date=1995 |volume=14 |issue=11 |pages=1859–1864 |doi=10.1002/etc.5620141107 |bibcode=1995EnvTC..14.1859G |language=en}}</ref>

===Air===
Manganese levels in the air decreased between 1953 and 1982, with higher levels in 1953. In general, breathing air with more than 5 micrograms of manganese per cubic meter can cause symptoms of manganese exposure. In lab-grown human kidney cells, higher levels of a protein called [[ferroportin]] are linked to lower manganese levels inside the cells and reduced [[cytotoxicity|cell damage]], shown by better glutamate uptake and less leakage of a damage marker known as [[lactate dehydrogenase]].<ref>Agency for Toxic Substances and Disease Registry (2012) [http://www.atsdr.cdc.gov/toxprofiles/tp151-c6.pdf 6. Potential for human exposure], in [https://www.atsdr.cdc.gov/toxprofiledocs/index.html?id=102&tid=23 ''Toxicological Profile for Manganese''], Atlanta, GA: U.S. Department of Health and Human Services.</ref><ref>{{cite journal|pmid=20002294|last1=Yin|first1=Z.|date=2010|pages=1190–8|issue=5|volume=112|last2=Jiang|first2=H.|journal=Journal of Neurochemistry|last3=Lee|first3=E. S.|last4=Ni|first4=M.|last5=Erikson|first5=K. M.|last6=Milatovic|first6=D.|last7=Bowman|first7=A. B.|last8=Aschner|first8=M.|title=Ferroportin is a manganese-responsive protein that decreases manganese cytotoxicity and accumulation |url=http://libres.uncg.edu/ir/uncg/f/K_Erickson_Ferroportin_2009.pdf|pmc=2819584|doi=10.1111/j.1471-4159.2009.06534.x}}</ref>

===Regulation===
Manganese exposure in [[United States]] is regulated by the [[Occupational Safety and Health Administration]] (OSHA).<ref name="osha.gov">{{cite web|title=Safety and Health Topics: Manganese Compounds (as Mn)|url=https://web.archive.org/web/20170801002948/https://www.osha.gov/dts/chemicalsampling/data/CH_250190.html|publisher=U.S. [[Occupational Safety and Health Administration]]}}</ref> People can be exposed to manganese in the workplace by breathing it in or swallowing it. OSHA has set the legal limit ([[permissible exposure limit]]) for manganese exposure in the workplace as 5&nbsp;mg/m<sup>3</sup> over an 8-hour workday. The [[National Institute for Occupational Safety and Health]] (NIOSH) has set a [[recommended exposure limit]] (REL) of 1&nbsp;mg/m<sup>3</sup> over an 8-hour workday and a short term limit of 3&nbsp;mg/m<sup>3</sup>. At levels of 500&nbsp;mg/m<sup>3</sup>, manganese is [[IDLH|immediately dangerous to life and health]].<ref>{{cite web|title=NIOSH Pocket Guide to Chemical Hazards – Manganese compounds and fume (as Mn)|url=https://www.cdc.gov/niosh/npg/npgd0379.html|publisher=Centers for Disease Control|access-date=19 November 2015}}</ref> In other countries, such as [[Germany]], a general ceiling value for airborne manganese has been set to 0.5&nbsp;mg/m<sup>3</sup> ({{interlanguage link|Maximale Arbeitsplatz-Konzentration|de}}) and the maximum level of manganese in the body has been set to 20&nbsp;mg/L.<ref name="ullmann" />