Manganese in drinking water may impair children's intellectual abilities
Manganese exposure in the workplace is known to have neurotoxic effects, but manganese occurs naturally in soil and sometimes in groundwater. One region where the groundwater contains naturally high levels of manganese is Quebec. A study involving 362 Quebec children, aged 6-13, has measured both the concentrations of metals (manganese, iron, copper, lead, zinc, arsenic, magnesium and calcium) in their tap water, and their cognitive abilities.