Manganese to life and health. Generally, exposure to ambient Mn air concentrations in excess of 5 μg Mn/m3 can lead to Mn-induced symptoms. Increased ferroportin protein expression in human embryonic kidney (HEK293) cells is associated with decreased intracellular Mn concentration and attenuated cytotoxicity, characterized by the reversal of Mn-reduced glutamate uptake and diminished lactate dehydrogenase leakage. 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
Manganese recovery of the manganese. For further purification, the manganese can then be sent to an electrowinning facility. In 1972 the CIA's Project Azorian, through billionaire Howard Hughes, commissioned the ship "Hughes Glomar Explorer" with the cover story of harvesting manganese nodules from the sea floor. That triggered a rush of activity to collect manganese nodules, which was not actually practical. The real mission of "Hughes Glomar Explorer" was to raise a sunken Soviet submarine, the K-129, with the goal of retrieving Soviet code books. Manganese has no satisfactory substitute in its major applications in metallurgy. In minor applications, (e.g., manganese