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Groundwater Contamination: Arsenic


Detecting and Treating Arsenic inWater

In Wisconsin, over 1,200 private drinking water wells have been found to contain elevated levels of inorganic arsenic, the most toxic form. The map shows counties where wells have tested positive for arsenic levels exceeding 10 parts per billion (ppb). The elevated levels in some areas, such as Outagamie, Winnebago, and Brown Counties, may be linked to increased water usage due to rapid suburban development.

What is it?

Arsenic, a naturally occurring element, has been detected in every county in the State of Wisconsin, raising concerns about its potential health hazards.

Where does it come from?

This element is often present in trace amounts in soil, bedrock formations, groundwater, lakes, rivers, ocean water, fruits, vegetables, and seafood. However, when groundwater passes through areas of high arsenic concentration, it can carry dangerous levels into well water.

Is it a health hazard?

Yes!Arsenic contamination of drinking water is a serious health concern. Drinking or cooking with arsenic-contaminated water has been associated with several serious health problems. If you think you or someone in your family has symptoms from arsenic exposure talk to your doctor and have your water tested for arsenic.

      •  Skin cancer
      • Internal cancers (bladder, prostate, lung and other sites)
      • Thick, rough skin on hands and feet
      • Unusual skin pigmentation (dappling of dark brown or white splotches)
      • Numbness in the hands and feet
      • Circulatory disorders
      • Tremors
      • Stomach pain, nausea, diarrhea
      • Diabetes
      • Depression

When should I test?

Regular testing for arsenic every five years is recommended for everyone, especially if the color of the water changes or you notice staining of fixtures.

To determine if arsenic is present in your water, testing by a certified laboratory is essential, as arsenic is odorless, tasteless, and invisible.


Our state-certified laboratory can either collect a sample onsite or provide you with a water sampling kit. It’s essential to follow the sampling directions provided.

If alterations in well water levels occur, testing becomes imperative. Being proactive about arsenic testing is key to ensuring the safety of your drinking water and maintaining a healthy living environment.

If my water tests positive, what should I do next?

If the arsenic level exceeds 10 ppb, it is crucial to refrain from drinking the water. Use water from a known safe source for consumption and food preparation, including baby formula, soup, and coffee. However, using the water for bathing and other household purposes is generally safe unless the arsenic level exceeds 100 ppb.

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Block arsenic from entering your home’s water with Arsenic Shield exclusively from U.S. Water.


The Right Solution Starts with an Accurate Test

U.S. Water offers comprehensive well water testing services through itsWisconsin state-certified water testing lab. This ensures the most accurate testing and, with our test facility onsite, you are guaranteed a fast turnaround time. In addition to our basic analysis, we offer a full range of certified water tests and well inspection services.

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