Manganese is achemical element; it hassymbolMn andatomic number 25. It is a hard, brittle, silvery metal, often found inminerals in combination withiron. First isolated in the 1770s, manganese is atransition metal with many industrialalloy uses, particularly instainless steels. It improves strength, workability, and resistance to wear. Manganese oxide is used as an oxidising agent, as a rubber additive, and in glass making, fertilizers, and ceramics. Manganese sulfate can be used as a fungicide.
Manganese is a silvery-graymetal that resemblesiron. It is hard and very brittle, difficult to melt, but oxidizes easily.[11] Manganese and its common ions areparamagnetic.[12] Manganese tarnishes slowly in air andoxidizes ("rusts") like iron in water containing dissolved oxygen.[13]
Naturally occurring manganese is composed of one stableisotope,55Mn. Severalradioisotopes have been isolated and described, ranging from46Mn to72Mn. The most stable are53Mn with ahalf-life of 3.7 million years,54Mn with a half-life of 312.08 days, and52Mn with a half-life of 5.591 days. All of the remainingradioactive isotopes have half-lives of less than three hours, and the majority of less than one minute. The primarydecay mode in isotopes lighter than the most abundant stable isotope,55Mn, iselectron capture, and the primary mode in heavier isotopes isbeta decay. Manganese also has threemeta states.[14]
Manganese is part of theiron group of elements, which are thought to be synthesized inmassive stars shortly before thesupernova explosion.[15]53Mn decays to53Cr with a half-life of 3.7 million years. Because of its short half-life,53Mn is relatively rare; it is produced by the impact ofcosmic rays oniron.[16]
Chromium and manganese are found together sufficiently for measurement of both to find application inisotope geology, and the Mn/Cr ratios here fordating the early Solar System. Mn–Cr isotopic ratios reinforce the evidence from26Al and107Pd for the early history of theSolar System. Variations in53Cr/52Cr and Mn/Cr ratios from severalmeteorites suggest a non-zero initial53Mn/55Mn ratio, which indicate that Cr isotopic composition variations must result fromin situ decay of53Mn in differentiated planetary bodies. Hence,53Mn provides additional evidence fornucleosynthetic processes immediately before the coalescence of the Solar System.[17]
Fourallotropes (structural forms) of solid manganese are known, labeled α, β, γ and δ, and occur at successively higher temperatures. All are metallic, stable at standard pressure, and have a cubic crystal lattice, but they vary widely in their atomic structures.[18][19][20]
Alpha manganese (α-Mn) is the equilibrium phase at room temperature. It has abody-centered cubic lattice and is unusual among elemental metals in that it has a very complexunit cell, with 58 atoms per cell (29 atoms perprimitive unit cell) with manganese atoms in four different types of surroundings (sites).[21][18] It isparamagnetic at room temperature andantiferromagnetic at temperatures below 95 K (−178 °C).[22]
Beta manganese (β-Mn) forms when heated above the transition temperature of 973 K (700 °C; 1,290 °F). It has a primitive cubic structure with 20 atoms per unit cell at two types of sites, which is as complex as that of any other elemental metal.[23] It is easily obtained as a metastable phase at room temperature by rapid quenching of manganese at 850 °C (1,120 K; 1,560 °F) in ice water. It does not showmagnetic ordering, remaining paramagnetic down to the lowest temperature measured (1.1 K).[23][24][25]
Gamma manganese (γ-Mn) forms when heated above 1,370 K (1,100 °C; 2,010 °F). It has a simple face-centered cubic structure (four atoms per unit cell). When quenched to room temperature it converts to β-Mn, but it can be stabilized at room temperature by alloying it with at least 5 percent of other elements (such as C, Fe, Ni, Cu, Pd or Au). These solute-stabilized alloys distort into a face-centeredtetragonal structure.[26][25]
Delta manganese (δ-Mn) forms when heated above 1,406 K (1,130 °C; 2,070 °F) and is stable up to the manganese melting point of 1,519 K (1,250 °C; 2,270 °F). It has abody-centered cubic structure (two atoms per cubic unit cell).[19][25]
Commonoxidation states of manganese are +2, +3, +4, +6, and +7, although all oxidation states from −3 to +7 have been observed. Manganese in oxidation state +7 is represented by salts of the intensely purple permanganate anionMnO−4.[28]Potassium permanganate is a commonly used laboratoryreagent because of its oxidizing properties; it is used as a topical medicine (for example, in the treatment of fish diseases). Solutions of potassium permanganate were among the first stains and fixatives to be used in the preparation of biological cells and tissues for electron microscopy.[29]
Aside from various permanganate salts, Mn(VII) is represented by the unstable, volatile derivative Mn2O7.Oxyhalides (MnO3F and MnO3Cl) are powerfuloxidizing agents.[11] The most prominent example of Mn in the +6 oxidation state is the green anionmanganate, [MnO4]2−. Manganate salts are intermediates in the extraction of manganese from its ores. Compounds with oxidation states +5 are somewhat elusive, and often found associated to an oxide (O2−) ornitride (N3−) ligand.[30] One example is the blue anionhypomanganate [MnO4]3−.[31]
Mn(IV) is somewhat enigmatic because it is common in nature but far rarer in synthetic chemistry. The most common Mn ore,pyrolusite, is MnO2. It is the dark brown pigment of manycave drawings[32] and is also a common ingredient indry cell batteries.[33] Complexes of Mn(IV), such as inK2[MnF6], are known but are rarer than those of manganese in the lower oxidation states. Mn(IV)-OH complexes are an intermediate in someenzymes, including the oxygen-evolving center (OEC) in plants.[34][35]
Aqueous solution of KMnO4 illustrating the deep purple of Mn(VII) as it occurs in permanganate
A particularly common oxidation state for manganese in aqueous solution is +2, which has a pale pink color. Many manganese(II) compounds are known, such as theaquo complexes derived frommanganese(II) sulfate (MnSO4) andmanganese(II) chloride (MnCl2). This oxidation state is also seen in the mineralrhodochrosite (manganese(II) carbonate). Manganese(II) commonly exists with ahigh-spin ground state, with 5 unpaired electrons, because of its high pairing energy. There are no spin-allowed d–d transitions in manganese(II), which explain its faint color.[37]
Manganese forms a large variety of organometallic derivatives, i.e., compounds with Mn-C bonds. The organometallic derivatives include numerous examples of Mn in its lower oxidation states, i.e. Mn(−III) up through Mn(I). This area of organometallic chemistry is attractive because Mn is inexpensive and of relatively low toxicity.[39]
Of greatest commercial interest ismethylcyclopentadienyl manganese tricarbonyl (MMT), which is used as ananti-knock compound added togasoline in some countries, featuring Mn(I).[40] Consistent with other aspects of Mn(II) chemistry,manganocene (Mn(C5H5)2) is high-spin. In contrast, its neighboring metal, iron, forms an air-stable, low-spin derivative in the form offerrocene (Fe(C5H5)2). When conducted under an atmosphere ofcarbon monoxide, reduction of Mn(II) salts givesdimanganese decacarbonylMn2(CO)10, an orange and volatile solid. The air-stability of this Mn(0) compound (and its many derivatives) reflects the powerful electron-acceptor properties of carbon monoxide. Manyalkene complexes andalkyne complexes are derived fromMn2(CO)10.[41]
In Mn(CH3)2(dmpe)2, Mn(II) is low spin, which contrasts with the high spin character of its precursor, MnBr2(dmpe)2 (dmpe = (CH3)2PCH2CH2P(CH3)2).[42] Polyalkyl and polyaryl derivatives of manganese often exist in higher oxidation states, reflecting the electron-releasing properties of alkyl and aryl ligands. One example is [Mn(CH3)6]2−.[43]
The origin of the name manganese is complex. In ancient times, two black minerals were identified from the regions of theMagnetes (eitherMagnesia, located within modern Greece, orMagnesia ad Sipylum, located within modern Turkey).[44] They were both calledmagnes from their place of origin, but were considered to differ in sex. The malemagnes attracted iron, and was the iron ore now known aslodestone ormagnetite, and which probably gave us the termmagnet. The femalemagnes ore did not attract iron, but was used to decolorize glass. This femalemagnes was later calledmagnesia, known now in modern times aspyrolusite ormanganese dioxide.[45] Neither this mineral nor elemental manganese is magnetic. In the 16th century, manganese dioxide was calledmanganesum (note the two Ns instead of one) by glassmakers, possibly as a corruption and concatenation of two words, sincealchemists and glassmakers eventually had to differentiate amagnesia nigra (the black ore) frommagnesia alba (a white ore, also from Magnesia, also useful in glassmaking). Italian physicianMichele Mercati called magnesia nigramanganesa, and finally the metal isolated from it became known asmanganese (German:Mangan). The namemagnesia was eventually used to refer only to the white magnesia alba (magnesium oxide), which provided the namemagnesium for the free element when it was isolated much later.[46]
Some of the cave paintings inLascaux,France, use manganese-based pigments.[47]
Manganese dioxide, which is abundant in nature, has long been used as a pigment. The cave paintings inGargas that are 30,000 to 24,000 years old are made from the mineral form of MnO2 pigments.[48]
Manganese compounds were used by Egyptian and Roman glassmakers, either to add to, or remove, color from glass.[49] Use as "glassmakers soap" continued through theMiddle Ages until modern times and is evident in 14th-century glass fromVenice.[50]
Credit for first isolating manganese is usually given toJohan Gottlieb Gahn.
Scheele and others were aware that pyrolusite (mineral form of manganese dioxide) contained a new element.Johan Gottlieb Gahn isolated an impure sample of manganese metal in 1774, which he did byreducing the dioxide withcarbon.[53] Ignatius Gottfried Kaim also may have reduced manganese dioxide to isolate the metal, but that is uncertain.[54][55]
The manganese content of some iron ores used in Greece led to speculations that steel produced from that ore contains additional manganese, making theSpartan steel exceptionally hard.[56] Around the beginning of the 19th century, manganese was used in steelmaking and several patents were granted. In 1816, it was documented that iron alloyed with manganese was harder but not more brittle. In 1837, British academicJames Couper noted an association between miners' heavy exposure to manganese and a form ofParkinson's disease.[57][58] In 1912, United States patents were granted for protecting firearms against rust and corrosion with manganese phosphate electrochemical conversion coatings, and the process has seen widespread use ever since.[59]
The invention of theLeclanché cell in 1866 and the subsequent improvement of batteries containing manganese dioxide as cathodicdepolarizer increased the demand for manganese dioxide. Until the development of batteries withnickel–cadmium and lithium, most batteries contained manganese. Thezinc–carbon battery and thealkaline battery normally use industrially produced manganese dioxide because naturally occurring manganese dioxide contains impurities. In the 20th century, manganese dioxide was widely used as the cathode for commercial disposable dry batteries of both the standard (zinc–carbon) and alkaline types.[60]
Percentage of manganese output in 2006 by countries[61]
The most important manganese ore is pyrolusite (MnO2). Other economically important manganese ores usually show a close spatial relation to the iron ores, such assphalerite.[11][64] Land-based resources are large but irregularly distributed. About 80% of the known world manganese resources are in South Africa; other important manganese deposits are in Ukraine, Australia, India, China,Gabon and Brazil.[61]
Manganese is mainly mined in South Africa, Australia, China, Gabon, Brazil, India, Kazakhstan, Ghana, Ukraine and Malaysia.[65] In South Africa, most identified deposits are located nearHotazel in theNorthern Cape Province, (Kalahari manganese fields), with a 2011 estimate of 15 billion tons. In 2011 South Africa produced 3.4 million tons, topping all other nations.[66]
An abundant resource of manganese in the form of manganese nodules found on theocean floor.[67] These nodules, which are composed of 29% manganese,[68] are located along the ocean floor. Theenvironmental impacts of nodule collection are of interest.[69][70] According to 1978 estimate, the ocean floor has 500 billion tons ofmanganese nodules.[71] As of April 2025[update], attempts to find economically viable methods of harvesting manganese nodules are still ongoing, however, none has been commercialized.[72]
In 1972, theCIA'sProject Azorian, through billionaireHoward Hughes, commissioned the shipHughes Glomar Explorer with the cover story of harvestingmanganese nodules from the sea floor.[73] This cover story triggered a rush of activity to collect manganese nodules. The real mission ofHughes Glomar Explorer was to raise a sunkenSoviet submarine, theK-129, with the goal of retrieving Soviet code books.[74]
Manganese also occurs in the oceanic environment, as dissolved manganese (dMn), which is found throughout the world's oceans, 90% of which originates from hydrothermal vents.[75] Particulate Mn develops in buoyant plumes over an active vent source, while the dMn behaves conservatively.[76] Mn concentrations vary between the water columns of the ocean. At the surface, dMn is elevated due to input from external sources such as rivers, dust, and shelf sediments. Coastal sediments normally have lower Mn concentrations, but can increase due to anthropogenic discharges from industries such as mining and steel manufacturing, which enter the ocean from river inputs. Surface dMn concentrations can also be elevated biologically through photosynthesis and physically from coastal upwelling and wind-driven surface currents. Internal cycling such as photo-reduction from UV radiation can also elevate levels by speeding up the dissolution of Mn-oxides and oxidative scavenging, preventing Mn from sinking to deeper waters.[77] Elevated levels at mid-depths can occur near mid-ocean ridges and hydrothermal vents. The hydrothermal vents release dMn enriched fluid into the water. The dMn can then travel up to 4,000 km due to the microbial capsules present, preventing exchange with particles, lowing the sinking rates. Dissolved Mn concentrations are even higher when oxygen levels are low. Overall, dMn concentrations are normally higher in coastal regions and decrease when moving offshore.[77]
Manganese occurs in soils in three oxidation states: the divalent cation, Mn2+ and as brownish-black oxides and hydroxides containing Mn (III,IV), such as MnOOH and MnO2. Soil pH and oxidation-reduction conditions affect which of these three forms of Mn is dominant in a given soil. At pH values less than 6 or under anaerobic conditions, Mn(II) dominates, while under more alkaline and aerobic conditions, Mn(III,IV) oxides and hydroxides predominate. These effects of soil acidity and aeration state on the form of Mn can be modified or controlled by microbial activity. Microbial respiration can cause both the oxidation of Mn2+ to the oxides, and it can cause reduction of the oxides to the divalent cation.[78]
The Mn(III,IV) oxides exist as brownish-black stains and small nodules on sand, silt, and clay particles. These surface coatings on other soil particles have high surface area and carry negative charge. The charged sites can adsorb and retain various cations, especially heavy metals (e.g., Cr3+, Cu2+, Zn2+, and Pb2+). In addition, the oxides can adsorb organic acids and other compounds. The adsorption of the metals and organic compounds can then cause them to be oxidized while the Mn(III,IV) oxides are reduced to Mn2+ (e.g., Cr3+ to Cr(VI) and colorlesshydroquinone to tea-coloredquinone polymers).[79]
A significant proportion of the manganese ore mined, around 85% in the United States, is used in iron andsteel production, such as in the production offerromanganese.[80] For the production of ferromanganese, the manganese ore is mixed with iron ore and carbon, and then reduced either in a blast furnace or in anelectric arc furnace.[81] The resulting ferromanganese has a manganese content of 30–80%.[11] Pure manganese used for the production of iron-free alloys is produced byleaching manganese ore withsulfuric acid and a subsequentelectrowinning process.[82]
Process flow diagram for a manganese refining circuit
A more progressive extraction process involves directly reducing (a low grade) manganese ore byheap leaching. This is done bypercolating natural gas through the bottom of the heap; the natural gas provides the heat (needs to be at least 850 °C) and the reducing agent (carbon monoxide). This reduces all of the manganese ore to manganese oxide (MnO), which is a leachable form. The ore then travels through agrinding circuit to reduce the particle size of the ore to between 150 and 250 μm, increasing the surface area to aid leaching. The ore is then added to a leach tank of sulfuric acid andferrous iron (Fe2+) in a 1.6:1 ratio. The iron reacts with themanganese dioxide (MnO2) to formiron hydroxide (FeO(OH)) and elemental manganese (Mn).[83]
This process yields greater than 90% recovery of the manganese. For further purification, the manganese can then be sent to anelectrowinning facility.[83]
Manganese is essential to iron andsteel production by virtue of itssulfur-fixing,deoxidizing, andalloying properties. Manganese has no satisfactory substitute in these applications in metallurgy.[61]Steelmaking,[84] including its ironmaking component, has accounted for most manganese demand, presently in the range of 85% to 90% of the total demand.[82] Manganese is a key component of low-coststainless steel.[85][86] Often ferromanganese (usually about 80% manganese) is the intermediate in modern processes.
Small amounts of manganese improve the workability of steel at high temperatures by forming a high-melting sulfide and preventing the formation of a liquidiron sulfide at the grain boundaries. If the manganese content reaches 4%, the embrittlement of the steel becomes a dominant feature. The embrittlement decreases at higher manganese concentrations and reaches an acceptable level at 8%. Steel containing 8 to 15% of manganese has a hightensile strength of up to 863 MPa.[87][88] Steel with 12% manganese was discovered in 1882 byRobert Hadfield and is still known asHadfield steel (mangalloy). It was used for British militarysteel helmets and later by the U.S. military.[89]
Manganese is used in production of alloys with aluminium. Aluminium with roughly 1.5% manganese has increased resistance to corrosion through grains that absorb impurities which would lead togalvanic corrosion.[90] The corrosion-resistantaluminium alloys 3004 and 3104 (0.8 to 1.5% manganese) are used for mostbeverage cans.[91] Before 2000, more than 1.6 milliontonnes of those alloys were used; at 1% manganese, this consumed 16,000 tonnes of manganese.[91]
Manganese(IV) oxide was used in the original type of dry cellbattery as an electron acceptor from zinc, and is the blackish material in carbon–zinc type flashlight cells. The manganese dioxide is reduced to the manganese oxide-hydroxide MnO(OH) during discharging, preventing the formation of hydrogen at the anode of the battery.[92]
MnO2 + H2O + e− → MnO(OH) +OH−
The same material also functions in neweralkaline batteries (usually battery cells), which use the same basic reaction, but a different electrolyte mixture. In 2002, more than 230,000 tons of manganese dioxide was used for this purpose.[60][92]
Copper alloys of manganese, such asManganin, are commonly found in metal elementshunt resistors used for measuring relatively large amounts of current. These alloys have very lowtemperature coefficient of resistance and are resistant to sulfur. This makes the alloys particularly useful in harsh automotive and industrial environments.[93][94]
Manganese oxide andsulfate are components of fertilizers. In the year 2000, an estimated 20,000 tons of these compounds were used in fertilizers in the US alone. A comparable amount of Mn compounds was also used in animal feeds.[40]
Manganese(IV) oxide (manganese dioxide, MnO2) is used as a reagent inorganic chemistry for theoxidation of benzylicalcohols (where thehydroxyl group is adjacent to anaromatic ring).[96] Manganese dioxide has been used since antiquity to oxidize and neutralize the greenish tinge in glass from trace amounts of iron contamination.[50] MnO2 is also used in the manufacture of oxygen and chlorine and in drying black paints. In some preparations, it is a brownpigment forpaint and is a constituent of naturalumber.[97]
Tetravalent manganese is used as anactivator in red-emittingphosphors. While many compounds are known which showluminescence,[98] the majority are not used in commercial application due to low efficiency or deep red emission.[99][100] However, several Mn4+ activated fluorides were reported as potential red-emitting phosphors for warm-white LEDs.[101][102] But to this day, only K2SiF6:Mn4+ is commercially available for use in warm-whiteLEDs.[103]
World-War-II-era 5-cent coin (1942-5 identified by mint mark P, D or S above dome) made from a 56% copper-35% silver-9% manganese alloy
The metal is occasionally used in coins; until 2000, the only United States coin to use manganese was the"wartime" nickel from 1942 to 1945.[104] An alloy of 75% copper and 25% nickel was traditionally used for the production of nickel coins. However, because of shortage of nickel metal during the war, it was substituted by more available silver and manganese, thus resulting in an alloy of 56% copper, 35% silver and 9% manganese. Since 2000,dollar coins, for example theSacagawea dollar and thePresidential $1 coins, are made from a brass containing 7% of manganese with a pure copper core.[105]
Manganese compounds have been used as pigments and for the coloring of ceramics and glass. The brown color of ceramic is sometimes the result of manganese compounds.[106] In the glass industry, manganese compounds are used for two effects.Manganese(III) reacts withiron(II) to reduce strong green color in glass by forming less-colored iron(III) and slightly pink manganese(II), compensating for the residual color of the iron(III).[50] Larger quantities of manganese are used to produce pink colored glass. In 2009,Mas Subramanian and associates atOregon State University discovered that manganese can be combined withyttrium andindium to form an intenselyblue, non-toxic, inert, fade-resistantpigment,YInMn Blue,[107] the first new blue pigment discovered in 200 years.[108]
Manganese is an essential humandietary element and is present as acoenzyme in several biological processes, which include macronutrient metabolism, bone formation, andfree radical defense systems. Manganese is a critical component in dozens of proteins and enzymes.[8] The human body contains about 12 mg of manganese, mostly in the bones. The soft tissue remainder is concentrated in the liver and kidneys.[9] In the human brain, the manganese is bound to manganesemetalloproteins, most notablyglutamine synthetase inastrocytes.[112]
TheU.S. Institute of Medicine (IOM) updated Estimated Average Requirements (EARs) and Recommended Dietary Allowances (RDAs) for minerals in 2001. For manganese, there was not sufficient information to set EARs and RDAs, so needs are described as estimates forAdequate Intakes (AIs). As for safety, the IOM setsTolerable upper intake levels (ULs) for vitamins and minerals when evidence is sufficient. In the case of manganese, the adult UL is set at 11 mg/day. Collectively the EARs, RDAs, AIs and ULs are referred to asDietary Reference Intakes (DRIs).[113] Manganese deficiency is rare.[114]
TheEuropean Food Safety Authority (EFSA) refers to the collective set of information as Dietary Reference Values, with Population Reference Intake (PRI) instead of RDA, and Average Requirement instead of EAR. AI and UL are defined the same as in the United States. For people ages 15 and older, the AI is set at 3.0 mg/day. AIs for pregnancy and lactation are 3.0 mg/day. For children ages 1–14 years, the AIs increase with age from 0.5 to 2.0 mg/day. The adult AIs are higher than the U.S. RDAs.[115] The EFSA reviewed the same safety question and decided that there was insufficient information to set a UL.[116]
For U.S. food and dietary supplement labeling purposes, the amount in a serving is expressed as a percent of Daily Value (%DV). For manganese labeling purposes, 100% of the Daily Value was 2.0 mg, but as of 27 May 2016 it was revised to 2.3 mg to bring it into agreement with the RDA.[117][118] A table of the old and new adult daily values is provided atReference Daily Intake.
Manganese deficiency in humans, which is rare, results in a number of medical problems.[113] A deficiency of manganese causes skeletal deformation in animals and inhibits the production of collagen in wound healing.[120]
Waterborne manganese has a greaterbioavailability than dietary manganese. According to results from a 2010 study,[121] higher levels of exposure to manganese indrinking water are associated with increasedintellectual impairment and reducedintelligence quotients 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 million Americans at risk.[122] 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.[123]
Mn levels can increase in seawater when hypoxic periods occur.[124] 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 ofimmunocytes and their functionality, such asphagocytosis and activation ofpro-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.[75]
Methylcyclopentadienyl manganese tricarbonyl (MMT) is an additive developed to replace lead compounds for gasolines to improve theoctane 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.[125]
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 calledferroportin are linked to lower manganese levels inside the cells and reducedcell damage, shown by better glutamate uptake and less leakage of a damage marker known aslactate dehydrogenase.[126][127]
Manganese is essential for human health, albeit in milligram amounts.[113] The current maximum safe concentration under U.S. EPA rules is 50 μg Mn/L.[131]
Manganese overexposure is most frequently associated withmanganism, a rare neurological disorder associated with excessive manganese ingestion or inhalation. Historically, persons employed in the production or processing of manganese alloys[132][133][134] have been at risk for developing manganism; however, health and safety regulations protect workers in developed nations.[128] The disorder was first described in 1837 by British academic John Couper, who studied two patients who were manganese grinders.[57]
Manganism is a biphasic disorder. In its early stages, an intoxicated person may experience depression, mood swings, compulsive behaviors, and psychosis. Early neurological symptoms give way to late-stage manganism, which resemblesParkinson's disease. Symptoms include weakness, monotone and slowed speech, an expressionless face, tremor, forward-leaning gait, inability to walk backwards without falling, rigidity, and general problems with dexterity, gait and balance.[57][135] UnlikeParkinson's disease, manganism is not associated with loss of the sense of smell and patients are typically unresponsive to treatment withL-DOPA.[136] Symptoms of late-stage manganism become more severe over time even if the source of exposure is removed and brain manganese levels return to normal.[135]
Chronic manganese exposure has been shown to produce a parkinsonism-like illness characterized by movement abnormalities.[137] This condition is not responsive totypical therapies used in the treatment of PD, suggesting an alternative pathway to the typicaldopaminergic loss within thesubstantia nigra.[137] Manganese may accumulate in thebasal ganglia, leading to the abnormal movements.[138] A mutation of the SLC30A10 gene, a manganese efflux transporter necessary for decreasing intracellular Mn, has been linked with the development of this Parkinsonism-like disease.[139] TheLewy bodies typical to PD are not seen in Mn-induced parkinsonism.[138]
Animal experiments have given the opportunity to examine the consequences of manganese overexposure under controlled conditions. In (non-aggressive) rats, manganese induces mouse-killing behavior.[140]
Manganese compounds are less toxic than those of other widespread metals, such asnickel andcopper.[141] However, exposure to manganese dusts and fumes should not exceed the ceiling value of 5 mg/m3 even for short periods because of its toxicity level.[142]Manganese poisoning has been linked toimpaired motor skills andcognitive disorders.[143]
A protein calledDMT1 is the major transporter in manganese absorption from the intestine and may be the major transporter of manganese across theblood–brain barrier. DMT1 also transports inhaled manganese across the nasalepithelium. The proposed mechanism for manganese toxicity is that dysregulation leads tooxidative stress,mitochondrial dysfunction, glutamate-mediatedexcitotoxicity, and aggregation of proteins.[144]
^abcArblaster, John W. (2018).Selected Values of the Crystallographic Properties of Elements. Materials Park, Ohio: ASM International.ISBN978-1-62708-155-9.
^Mn(–2) is known inMn(cod)2−2; seeJohn E. Ellis (2006). "Adventures with Substances Containing Metals in Negative Oxidation States".Inorganic Chemistry.45 (8):3167–3186.doi:10.1021/ic052110i.
^abErikson, Keith M.; Ascher, Michael (2019). "Chapter 10. Manganese: Its Role in Disease and Health". In Sigel, Astrid; Freisinger, Eva; Sigel, Roland K. O.; Carver, Peggy L. (eds.).Essential Metals in Medicine:Therapeutic Use and Toxicity of Metal Ions in the Clinic. Metal Ions in Life Sciences. Vol. 19. Berlin: de Gruyter GmbH. pp. 253–266.doi:10.1515/9783110527872-016.ISBN978-3-11-052691-2.PMID30855111.S2CID73725546.
^abcdHolleman, Arnold F.; Wiberg, Egon; Wiberg, Nils (1985). "Mangan".Lehrbuch der Anorganischen Chemie (in German) (91–100 ed.). Walter de Gruyter. pp. 1110–1117.ISBN978-3-11-007511-3.
Trinquier, A.; Birck, J.; Allègre, C.; Göpel, C.; Ulfbeck, D. (2008). "53Mn–53Cr systematics of the early Solar System revisited".Geochimica et Cosmochimica Acta.72 (20):5146–5163.Bibcode:2008GeCoA..72.5146T.doi:10.1016/j.gca.2008.03.023.
^Kemmitt, R. D. W.; Peacock, R. D. (1973).The Chemistry of Manganese, Technetium and Rhenium. Pergamon Texts in Inorganic Chemistry. Saint Louis: Elsevier Science. p. 778.ISBN978-1-4831-3806-0.OCLC961064866.
^abcDuschanek, H.; Mohn, P.; Schwarz, K. (1989). "Antiferromagnetic and ferromagnetic gamma-manganese generalisation of the fixed-spin-moment method".Physica B: Condensed Matter.161 (1–3):139–142.doi:10.1016/0921-4526(89)90120-8.ISSN0921-4526.
Man, Wai-Lun; Lam, William W. Y.; Lau, Tai-Chu (2014). "Reactivity of Nitrido Complexes of Ruthenium(VI), Osmium(VI), and Manganese(V) Bearing Schiff Base and Simple Anionic Ligands".Accounts of Chemical Research.47 (2):427–439.doi:10.1021/ar400147y.PMID24047467.
Goldberg, David P. (2007). "Corrolazines: New Frontiers in High-Valent Metalloporphyrinoid Stability and Reactivity".Accounts of Chemical Research.40 (7):626–634.doi:10.1021/ar700039y.PMID17580977.
^Arslan, Evrim; Lalancette, Roger A.; Bernal, Ivan (2017). "An historic and scientific study of the properties of metal(III) tris-acetylacetonates".Struct Chem.28 (1):201–212.Bibcode:2017StrCh..28..201A.doi:10.1007/s11224-016-0864-0.
^Rayner-Canham, Geoffrey; Overton, Tina (2003).Descriptive Inorganic Chemistry. Macmillan. p. 491.ISBN0-7167-4620-4..
^Schmidt, Max (1968). "VII. Nebengruppe".Anorganische Chemie II (in German). Wissenschaftsverlag. pp. 100–109.
^Kadassery, Karthika J.; MacMillan, Samantha N.; Lacy, David C. (2019). "Resurgence of Organomanganese(I) Chemistry. Bidentate Manganese(I) Phosphine–Phenol(ate) Complexes".Inorganic Chemistry.58 (16):10527–10535.doi:10.1021/acs.inorgchem.9b00941.PMID31247867.
^Girolami, Gregory S.; Wilkinson, Geoffrey; Thornton-Pett, Mark; Hursthouse, Michael B. (1983). "Hydrido, alkyl, and ethylene 1,2-bis(dimethylphosphino)ethane complexes of manganese and the crystal structures of MnBr2(dmpe)2, [Mn(AlH4)(dmpe)2]2 and MnMe2(dmpe)2".Journal of the American Chemical Society.105 (22):6752–6753.Bibcode:1983JAChS.105.6752G.doi:10.1021/ja00360a054.
^Robert J. Morris; Gregory S. Girolami (1988). "Permethylmanganates. Synthesis and characterization of divalent [MnMe42-], trivalent [MnMe52-], and tetravalent [MnMe62-]".Journal of the American Chemical Society.110 (18). ACS Publications:6245–6246.Bibcode:1988JAChS.110.6245M.doi:10.1021/ja00226a049.PMID22148809.
^languagehat (28 May 2005)."MAGNET".languagehat.com. Retrieved18 June 2020.
^Chalmin, Emilie; Menu, Michel; Vignaud, Colette (2003). "Analysis of rock art painting and technology of Palaeolithic painters".Measurement Science and Technology.14 (9):1590–1597.doi:10.1088/0957-0233/14/9/310.S2CID250842390.
^Peter Schmittinger; Thomas Florkiewicz; L. Calvert Curlin; Benno Lüke; Robert Scannell; Thomas Navin; Erich Zelfel; Rüdiger Bartsch (2011). "Chlorine".Ullmann's Encyclopedia of Industrial Chemistry. p. 532.doi:10.1002/14356007.a06_399.pub3.ISBN9783527306732.
^"Braunstein".mindat.org. Mindat. Retrieved23 April 2025.
^Alessio, L.; Campagna, M.; Lucchini, R. (2007). "From lead to manganese through mercury: mythology, science, and lessons for prevention".American Journal of Industrial Medicine.50 (11):779–787.doi:10.1002/ajim.20524.hdl:11380/1318816.PMID17918211.
^abcCouper, John (1837). "On the effects of black oxide of manganese when inhaled into the lungs".Br. Ann. Med. Pharm. Vital Stat. Gen. Sci.1:41–42.
^Olsen, Sverre E.; Tangstad, Merete; Lindstad, Tor (2007). "History of omanganese".Production of Manganese Ferroalloys. Tapir Academic Press. pp. 11–12.ISBN978-82-519-2191-6.
^abPreisler, Eberhard (1980). "Moderne Verfahren der Großchemie: Braunstein".Chemie in unserer Zeit (in German).14 (5):137–148.doi:10.1002/ciuz.19800140502.
^Bhattacharyya, P. K.; Dasgupta, Somnath; Fukuoka, M.; Roy Supriya (1984). "Geochemistry of braunite and associated phases in metamorphosed non-calcareous manganese ores of India".Contributions to Mineralogy and Petrology.87 (1):65–71.Bibcode:1984CoMP...87...65B.doi:10.1007/BF00371403.S2CID129495326.
^International Seabed Authority."Polymetallic Nodules"(PDF).isa.org. International Seabed Authority. Archived fromthe original(PDF) on 23 October 2021. Retrieved2 February 2021.
^Wang, X; Schröder, HC; Wiens, M; Schlossmacher, U; Müller, WEG (2009). "Manganese/polymetallic nodules: micro-structural characterization of exolithobiontic- and endolithobiontic microbial biofilms by scanning electron microscopy".Micron.40 (3):350–358.doi:10.1016/j.micron.2008.10.005.PMID19027306.
^Bartlett, Richmond; Ross, Donald (2005). "Chemistry of Redox Processes in Soils". In Tabatabai, M.A.; Sparks, D.L. (eds.).Chemical Processes in Soils. SSSA Book Series, no. 8. Madison, Wisconsin: Soil Science Society of America. pp. 461–487.LCCN2005924447.
^Dixon, Joe B.; White, G. Norman (2002). "Manganese Oxides". In Dixon, J.B.; Schulze, D.G. (eds.).Soil Mineralogy with Environmental Applications. SSSA Book Series no. 7. Madison, Wisconsin: Soil Science Society of America. pp. 367–386.LCCN2002100258.
^Corathers, L. A.; Machamer, J. F. (2006)."Manganese".Industrial Minerals & Rocks: Commodities, Markets, and Uses (7th ed.). SME. pp. 631–636.ISBN978-0-87335-233-8.
^abZhang, Wensheng; Cheng, Chu Yong (2007). "Manganese metallurgy review. Part I: Leaching of ores/secondary materials and recovery of electrolytic/chemical manganese dioxide".Hydrometallurgy.89 (3–4):137–159.Bibcode:2007HydMe..89..137Z.doi:10.1016/j.hydromet.2007.08.010.
^Tweedale, Geoffrey (1985). "Sir Robert Abbott Hadfield F.R.S. (1858–1940), and the Discovery of Manganese Steel Geoffrey Tweedale".Notes and Records of the Royal Society of London.40 (1):63–74.doi:10.1098/rsnr.1985.0004.JSTOR531536.S2CID73176861.
^abDell, R. M. (2000). "Batteries fifty years of materials development".Solid State Ionics.134 (1–2):139–158.doi:10.1016/S0167-2738(00)00722-0.
^David B. Wellbeloved; Peter M. Craven; John W. Waudby (2000). "Manganese and Manganese Alloys".Ullmann's Encyclopedia of Industrial Chemistry. Wiley.doi:10.1002/14356007.a16_077.ISBN9783527306732.
^"WSK1216"(PDF).vishay. Vishay Intertechnology. Retrieved30 April 2022.
^Gérard Cahiez; Mouâd Alami; Richard J. K. Taylor; Mark Reid; Jonathan S. Foot; Lee Fader; Vikas Sikervar; Jagadish Pabba (2017). "Manganese Dioxide".Encyclopedia of Reagents for Organic Synthesis.doi:10.1002/047084289X.rm021.pub4.ISBN9780470842898.
^Chen, Daquin; Zhou, Yang; Zhong, Jiasong (2016). "A review on Mn4+ activators in solids for warm white light-emitting diodes".RSC Advances.6 (89):86285–86296.Bibcode:2016RSCAd...686285C.doi:10.1039/C6RA19584A.
^Baur, Florian; Jüstel, Thomas (2016). "Dependence of the optical properties of Mn4+ activated A2Ge4O9 (A=K,Rb) on temperature and chemical environment".Journal of Luminescence.177:354–360.Bibcode:2016JLum..177..354B.doi:10.1016/j.jlumin.2016.04.046.
^Zhou, Zhi; Zhou, Nan; Xia, Mao; Yokoyama, Meiso; Hintzen, H. T. (Bert) (6 October 2016). "Research progress and application prospects of transition metal Mn4+-activated luminescent materials".Journal of Materials Chemistry C.4 (39):9143–9161.doi:10.1039/c6tc02496c.
^Shepard, Anna Osler (1956). "Manganese and Iron–Manganese Paints".Ceramics for the Archaeologist. Carnegie Institution of Washington. pp. 40–42.ISBN978-0-87279-620-1.{{cite book}}:ISBN / Date incompatibility (help)
^Rice, Derek B.; Massie, Allyssa A.; Jackson, Timothy A. (2017). "Manganese–Oxygen Intermediates in O–O Bond Activation and Hydrogen-Atom Transfer Reactions".Accounts of Chemical Research.50 (11):2706–2717.doi:10.1021/acs.accounts.7b00343.PMID29064667.
^Dismukes, G. Charles; Willigen, Rogier T. van (2006). "Manganese: The Oxygen-Evolving Complex & Models".Manganese: The Oxygen-Evolving Complex & Models Based in part on the article Manganese: Oxygen-Evolving Complex & Models by Lars-Erik Andréasson & Tore Vänngård which appeared in the Encyclopedia of Inorganic Chemistry, First Edition, First Edition.Encyclopedia of Inorganic Chemistry.doi:10.1002/0470862106.ia128.ISBN978-0470860786.
^abcdInstitute of Medicine (US) Panel on Micronutrients (2001)."Manganese".Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Chromium, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Chromium. National Academy Press. pp. 394–419.ISBN978-0-309-07279-3.PMID25057538.
^Silva Avila, Daiana; Luiz Puntel, Robson; Aschner, Michael (2013). "Manganese in Health and Disease". In Astrid Sigel; Helmut Sigel; Roland K. O. Sigel (eds.).Interrelations between Essential Metal Ions and Human Diseases. Metal Ions in Life Sciences. Vol. 13. Springer. pp. 199–227.doi:10.1007/978-94-007-7500-8_7.ISBN978-94-007-7499-5.PMC6589086.PMID24470093.
^Devenyi, A. G; Barron, T. F; Mamourian, A. C (1994). "Dystonia, hyperintense basal ganglia, and high whole blood manganese levels in Alagille's syndrome".Gastroenterology.106 (4):1068–71.doi:10.1016/0016-5085(94)90769-2.PMID8143974.S2CID2711273.
^Arthur W. Garrison; N. Lee Wolfe; Robert R. Swank Jr.; Mark G. Cipollone (1995). "Environmental fate of methylcyclopentadienyl manganese tricarbonyl".Environmental Toxicology and Chemistry.14 (11):1859–1864.Bibcode:1995EnvTC..14.1859G.doi:10.1002/etc.5620141107.
^Brent Furbee (2009)."Manganese".Clinical Neurotoxicology. Elsevier. pp. 293–301.ISBN9780323052603. Retrieved5 May 2025.
^Baselt, R. (2008)Disposition of Toxic Drugs and Chemicals in Man, 8th edition, Biomedical Publications, Foster City, CA, pp. 883–886,ISBN0-9626523-7-7.
^Lazrishvili, I.; et al. (2016). "Manganese loading induces mouse-killing behaviour in nonaggressive rats".Journal of Biological Physics and Chemistry.16 (3):137–141.doi:10.4024/31LA14L.jbpc.16.03.
^"Manganese Chemical Background". Metcalf Institute for Marine and Environmental Reporting University of Rhode Island. April 2006. Archived fromthe original on 28 August 2006. Retrieved30 April 2008.
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