USGS maps arsenic concentrations


  • Randy Showstack


About 10% of U.S. groundwater samples analyzed as part of a new U.S. Geological Survey (USGS) study exceed the World Health Organization's (WHO) guideline for arsenic in drinking water.

A USGS map of arsenic concentrations in groundwater across the U.S., released on May 8, shows the highest concentrations were found in samples taken from states in the Southwest and Rocky Mountain region, as well as in sections of the Midwest and Northeast.