Mn (manganese)

UNICERT is the leading inspection body in the area of water quality test for Manganese (Mn) and objectives to reduce environmental emission/pollution and enhance environmental performance to the society.

Manganese (Mn):

Manganese is a chemical element with symbol Mn and atomic number 25. It is not found as a free element in nature; it is often found in minerals in combination with iron. Manganese is a metal with important industrial metal alloy uses, particularly in stainless steels. Historically, manganese is named for pyrolusite and other black minerals from the region of Magnesia in Greece, which also gave its name to magnesium and the iron ore magnetite. By the mid-18th century, Swedish-German chemist Carl Wilhelm Scheele had used pyrolusite to produce chlorine. Scheele and others were aware that pyrolusite (now known to be manganese dioxide) contained a new element, but they were unable to isolate it. Johan Gottlieb Gahn was the first to isolate an impure sample of manganese metal in 1774, which he did by reducing the dioxide with carbon.

Manganese phosphating is used for rust and corrosion prevention on steel. Ionized manganese is used industrially as pigments of various colors, which depend on the oxidation state of the ions. The permanganates of alkali and alkaline earth metals are powerful oxidizers. Manganese dioxide is used as the cathode (electron acceptor) material in zinc-carbon and alkaline batteries.

In biology, manganese (II) ions function as cofactors for a large variety of enzymes with many functions. Manganese enzymes are particularly essential in detoxification of superoxide free radicals in organisms that must deal with elemental oxygen. Manganese also functions in the oxygen-evolving complex of photosynthetic plants. While the element is a required trace mineral for all known living organisms, it also acts as a neurotoxin in larger amounts. Especially through inhalation, it can cause manganism, a condition in mammals leading to neurological damage that is sometimes irreversible.

 

Environmental health concerns:

Manganese in drinking water

Waterborne manganese has a greater bioavailability than dietary manganese. According to results from a 2010 study, higher levels of exposure to manganese in drinking water are associated with increased intellectual impairment and reduced intelligence 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. 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.

Manganese in gasoline

Methylcyclopentadienyl manganese tricarbonyl (MMT) is a gasoline additive used to replace lead compounds for unleaded gasolines to improve the octane rating of low octane petroleum distillates. It reduces engine knock agent through the action of the carbonyl groups. Fuels containing manganese tend to form manganese carbides, which damage exhaust valves.

Compared to 1953, levels of manganese in air have dropped.[80] Many racing competitions specifically ban manganese compounds in racing fuel for carts and minibikes. MMT contains 24.4–25.2% manganese. Elevated atmospheric manganese concentrations are strongly correlated with automobile traffic density. The Level of manganese emitted by MMT fuels has been found to be safe for the general population and vulnerable groups such as infants and the elderly by the EPA and European and Canadian environmental agencies.

Manganese in tobacco smoke

The tobacco plant readily absorbs and accumulates heavy metals such as manganese from the surrounding soil into its leaves. These are subsequently inhaled during tobacco smoking. While manganese is a constituent of tobacco smoke, studies have largely concluded that concentrations are not hazardous for human health.

 

Interested Parties including Regulatory Authorities:

  1. Persons affected by Mn
  2. Industries, Laboratories using/ Generating Mn
  3. Personal and commercial uses
  4. Private / Govt. Projects to control Mn
  5. Handling and transportation of goods containing Mn
  6. Local Environmental Department/ Authorities
  7. Local Government Authorities like Municipalities, City Corporation etc.
  8. Local Law Enforcing Agencies like Police, Magistrate and Regulatory Authorities etc.

 

Benefit of Monitoring:

By monitoring long-term contamination trends, every country establishes baseline contamination levels, making it possible for early identification of contamination events. Daily events and long term trends are captured and taken step to reduce environmental emission/ pollution and enhance environmental performance of the society.