Manganese can make water toxic

Water contaminated with manganese not only tastes vile but also can limit the intellectual development of children drinking it, a new study finds.

While studying the arsenic-tainted wells of Bangladesh several years ago, scientists turned up another natural pollutant there: manganese. The World Health Organization’s pollutant standard for the metal is 500 micrograms per liter (µg/l) of drinking water, and contamination in some Bangladesh wells far exceeded that amount.