Steven G. Gilbert, PhD, DABT
Director and Founder of the Institute of Neurotoxicology and Neurological Disorders
We have heard a lot about the adverse effects of lead, even at very low levels of exposure, on the intellectual development of children, and now there is further evidence that manganese exposure from drinking water causes similar harm to children. A new study by Maryse Bouchard and co-authors1 describes the adverse effects of manganese exposure from drinking water on childhood IQ. Manganese is a very interesting metal, widely distributed and occurring naturally in food and drinking water. It is a well-established neurotoxicant. Unlike lead, which has no known biological function, manganese is an essential nutrient and in trace amounts is necessary for growth and development. In industry, manganese is used to harden steel, and manganese fumes during welding are a work place hazard.