Manganese in drinking water

A new study has been appearing in news reports over the past couple of days: a group of researchers found that children drinking water with high levels of manganese had lower IQs than children drinking water with lower levels of manganese. Obviously no parent wants their children to have a lower IQ, but the media reports don’t really provide much information on whether this study indicates any sort of risk to the general population, so I thought I’d take a more in-depth look at the study in the context of what we know about manganese in drinking water supplies.