In biology, manganese(II) ions function as cofactors for a large variety ofenzymes with many functions.[1]Manganese enzymes are particularly essential in detoxification of superoxidefree radicals in organisms that must deal with elemental oxygen. Manganese also functions in the oxygen-evolving complex of photosynthetic plants. The element is a required trace mineral for all known living organisms. In larger amounts, and apparently with far greater activity by inhalation, it can cause a poisoning syndrome in mammals, with neurological damage which is sometimes irreversible.