Private well water should be tested yearly to reduce health risks to children

May 26 2009

Private well water should be tested yearly, and in some cases more often, according to new guidance offered by the American Academy of Pediatrics (AAP).

Researchers at the National Institute of Environmental Health Sciences (NIEHS), part of the National Institutes of Health, took a lead role in working with the AAP to develop these recommendations and draft a new AAP policy statement about the things parents should do if their children drink well water. The recommendations call for annual well testing, especially for nitrate and microorganisms such as coliform bacteria, which can indicate that sewage has contaminated the well. The recommendations point out circumstances when additional testing should occur, including testing when there is a new infant in the house or if the well is subjected to structural damage.

"Children are especially vulnerable to waterborne illnesses that may come from contaminated wells," said Walter J. Rogan, M.D., an epidemiologist at NIEHS and lead author on the policy statement and technical report that appears in the June issue of Pediatrics. The new policy statement, "Drinking Water from Private Wells and Risks to Children," offers recommendations for inspection, testing and remediation of wells providing drinking water for children.

"With few exceptions, well owners are responsible for their own wells," said Rogan. Private wells are not subject to federal regulations and are only minimally regulated by states. With proper care, well water is safe; however, wells can become contaminated by chemicals or pathogenic organisms.

Nitrate, which comes from sewage or fertilizer, is the most common contaminant in wells. The presence of nitrates can be a problem particularly for infants under three months who can not metabolize nitrate. Water with a nitrate concentration of more than 1.0 milligrams per liter should not be used to prepare infant formula or given to a child younger than one year. The policy statement suggests using bottled water for infants when nitrate contamination is detected, or when the source of drinking water is not known.

The policy statement and accompanying technical report point out that water contamination is inherently local, and that families with wells need to keep in contact with state and local health experts to determine what should be tested in their community. For example, some parts of the country may have arsenic, radon, salt intrusion or agricultural runoff that may get into the water supply.

"As people move out of urban and suburban areas into areas that are not reached by municipal water supplies, it is more important than ever that people know who to contact in their local health department to get information about local groundwater conditions," said N. Beth Ragan of NIEHS, who served as consultant on these reports. A compilation of state by state telephone and Web-based resources of local experts is included in the technical report. Approximately one-sixth of U.S. households now get their drinking water from private wells.

NIEHS Director Linda Birnbaum, Ph.D., says she is pleased that NIEHS researchers took the lead in writing this statement, and continue their longstanding liaisons with the American Academy of Pediatrics to develop state-of-the-science technical reports that can have a direct impact on public health.

"This statement will be extremely useful to many audiences - especially pediatricians," Birnbaum said. "Pediatricians needed a one-stop shopping document that they can share with parents who have concerns about their children's sources of drinking water."