Arsenic in Your Drinking Water?

Boy drinking water
Wherever you live, if you drink from a private well, get your water tested

Arsenic: colorless, tasteless, odorless, ubiquitous in nature, a favored homicidal agent since the first century. A naturally occurring element, arsenic exists in rocks and soils throughout the world.

In arsenic “hot spots,” natural processes can cause the toxic element to migrate into the water people tap for household wells. Exposure to arsenic through drinking water is linked to reduced immune function, cardiovascular disease, diabetes, respiratory illnesses, some cancers, and other ills.

News of several recently published studies report that even at relatively low levels of long-term exposure, arsenic can harm human health.

For example, low to moderate amounts of arsenic in drinking water may irreversibly damage lungs in ways that mimic decades of heavy smoking.
Newly published Dartmouth research found that the greater the arsenic exposure in a pregnant woman, the greater the number and severity of respiratory and diarrheal infections in their infants. The Dartmouth researchers have also found a link between maternal arsenic exposure and low birth-weight babies.

The sobering news
Water-quality experts estimate that 13 million Americans get their drinking water from private wells with arsenic levels above the federal standard of 10 parts per billion.

While federal law requires regular testing of public drinking water supplies to meet the federal Environmental Protection Agency standards, neither EPA nor any states require testing for private wells.

“The common barriers to testing (for arsenic or other contaminants) include knowledge of what to test for and where to send the sample,” says Kevin Masarik, groundwater education specialist with the University of Wisconsin Extension.

Masarik says about a third of Wisconsin residents drink from private wells, and estimates that fewer than 10 percent of those wells have been tested for arsenic. “Generally, the only time a well gets tested is right after the well is first constructed, and then, only for bacteria,” he says.

In Wisconsin, “Extension’s educational programs work at different scales–statewide, county, and local. We put out timely press releases. Many county Extension offices distribute water-testing bottles residents can mail back. In other counties Extension personnel work with county health departments or soil and water departments,” Masarik says.

“We also host water-testing events where bottles get distributed locally and residents bring them to common collection sites. This makes it convenient for people to get over that hurdle of how to collect the sample, what to test for, and where to send their samples.”

“We recommend testing at least once for arsenic, then every year or so if results reveal any level of contamination with arsenic.” Although arsenic is tasteless and odorless, Masarik says, “We also suggest testing if you notice any changes in the way your water tastes, smells, or looks, as these changes may indicate changes in the underlying hydrology of the area.”

Masarik notes that prolonged drought or increased water use, and loss of recharge area can sometimes result in fluctuations of the water table that allows more oxygen from the soil or air into the aquifer, which in turn may leach more arsenic from bedrock.

Drew Gholson, program specialist, and Diane Boellstorff, assistant professor and Extension water specialist, are part of a Texas A & M Extension team providing educational outreach to Texas’s estimated 2.3 million private well owners.

They work through the Texas Well Owners Network (TWON), in partnership with the Texas Water Resources Institute.

In addition to offering an impressive collection of fact sheets for programs, TWON works with county Extension offices throughout Texas to distribute sample bottles and instructions for filling and where to send them for analysis.

“We travel throughout the state, offering daylong ‘Well Educated’ trainings and one-hour ‘Well Informed’ screenings,” Gholson says. “At both events, residents can bring well-water samples to be field-screened. If analysis detects contaminants, we urge the well owner to submit a sample to a certified lab.”

Boellstorff says strategies for households with arsenic-contaminated wells include using bottled water for cooking and drinking, extending a well casing, drilling a new well, or installing one of various treatment systems that reduce the contaminant.

“We recommend annual testing for all private drinking-water wells.” says Boellstorff, “especially if the results show any level of arsenic.

“If it was my drinking water, and the analysis showed any level of arsenic” she adds, “I’d be inclined to test it at six-month intervals.”


Arsenic Map

Learn more


Released October 22, 2013

Sources: Kevin Masarik, M.S., University of Wisconsin, Stevens Point,
Drew Gholson, Master of Water Management, Texas A&M AgriLife Extension,
Diane Boellstorff, Ph.D., Texas A&M AgriLife Extension,

Writer: Peg Boyles, eXtension,

Photo from Flickr account kretyen Some rights reserved.