how toxic is it?
At levels of 500 mg/m, manganese is immediately dangerous to life and health.
Manganese
Manganese compounds are less toxic than those of other widespread metals, such as nickel and copper. However, exposure to manganese dusts and fumes should not exceed the ceiling value of 5 mg/m even for short periods because of its toxicity level. Manganese poisoning has been linked to impaired motor skills and cognitive disorders.

Permanganate exhibits a higher toxicity than manganese(II) compounds. The fatal dose is about 10 g, and several fatal intoxications have occurred. The strong oxidative effect leads to necrosis of the mucous membrane. For example, the esophagus is affected if the permanganate is swallowed. Only a limited amount is absorbed by the intestines, but this small amount shows severe effects on the kidneys and on the liver.

Manganese exposure in United States is regulated by the Occupational Safety and Health Administration (OSHA). People can be exposed to manganese in the workplace by breathing it in or swallowing it. OSHA has set the legal limit (permissible expo
in which of the following does manganese have the highest oxidation number Manganese compounds where manganese is in oxidation state +7, which are mostly restricted to the unstable oxide MnO, compounds of the intensely purple permanganate anion MnO, and a few oxyhalides (MnOF and MnOCl), are powerful oxidizing agents. are there any developmental disorders associated with it? Yes - short-term memory, visual identification, diminished IQ scores what is its role in human biology? It is present as a coenzyme in several biological processes, which include macronutrient metabolism, bone formation, and free radical defense systems. It is a critical component in dozens of proteins and enzymes. and its role in plants? In photosynthetic oxygen evolution in chloroplasts in plants.
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Manganese [SEP] Precautions
Manganese compounds are less toxic than those of other widespread metals, such as nickel and copper. However, exposure to manganese dusts and fumes should not exceed the ceiling value of 5 mg/m even for short periods because of its toxicity level. Manganese poisoning has been linked to impaired motor skills and cognitive disorders. Permanganate exhibits a higher toxicity than manganese(II) compounds. The fatal dose is about 10 g, and several fatal intoxications have occurred. The strong oxidative effect leads to necrosis of the mucous membrane. For example, the esophagus is affected if the permanganate is swallowed. Only a limited amount is absorbed by the intestines, but this small amount shows severe effects on the kidneys and on the liver.