Increased exposure to lead-contaminated drinking water in Washington, DC, is a possible cause for a sharp increase in fetal deaths and somewhat lower birth rates in the region in 2000 to 2003 and again from 2007 to 2009, according to a new study published online by the journal Environmental Science and Technology.

The study attributes the spike in fetal deaths from 2001-2003 to a switch in drinking water disinfectant from chlorine to chloramine, which caused an unintended release of lead from plumbing material into drinking water.