Manganese risk in groundwater affects 200 million people, study shows

Manganese is an essential trace element. However, in excessive concentrations, the metal can cause health problems. Two Eawag researchers have now produced a global risk map for manganese in groundwater. Half of the world's population uses groundwater as drinking water. According to the study, between 180 million and 220 million people could be using water with elevated manganese concentrations as drinking water—significantly more than previously thought. Densely populated regions of Asia are particularly affected.