Oct 27, 2017

Arsenic Exposure Threatens Private Well Owners

Recent study estimates 2.1 million Americans may be at risk of exposure

The National Ground Water Assn. (NGWA) announced that a new national study estimates 2.1 million Americans on household water wells may be at risk of harmful exposure to arsenic.

“Our standard advice to private well owners is to test water for anything of local concern,” said Cliff Treyens, NGWA director of public outreach. “Contamination threats can vary from locale to locale with some caused by human activity and others such as arsenic occurring naturally in the environment. A good place to check on local groundwater contamination threats is the county health department.”

The study by the U.S. Geological Survey and the Centers for Disease Control’s National Center for Environmental Health shows areas potentially affected by arsenic levels greater than 10 parts per billion—the federally established “maximum contaminant level” at which regulated public water systems are required to take corrective action. Private well water quality, however, is not regulated by the government on an ongoing basis. Private well owners are responsible for testing their water and taking action to keep it safe. Well owners can look up their county health department on NGWA’s website.

The study’s top 10 states for people at risk for harmful arsenic exposure based on the size of the at-risk population are:

  1. Michigan, 192,747;
  2. Ohio, 189,191;
  3. Indiana, 150,858;
  4. North Carolina, 119,633;
  5. California, 115,823;
  6. Maine, 102,452;
  7. Texas, 95,455;
  8. Pennsylvania, 80,729;
  9. Minnesota, 80,353; and
  10. Wisconsin, 72,670.

Significantly, the study may shed new light on areas not known to have arsenic issues in the groundwater.

“We identify areas of high and low potential exposure in areas of limited arsenic data. These areas may be viewed as potential areas to investigate further or to compare to more detailed local information,” the study states.

To help well owners address the issue of arsenic in well water, NGWA has developed educational tools on testing water and treatment if necessary. These tools include: