Nitrate in Private Well Water and Health

nitrate in private well water

Exposure and Risk

Infants under the age of 6 months who drink water containing more than 1 mg/L nitrite, or 10 mg/L nitrate, could become seriously ill and, if untreated, may die. In the body, nitrate changes to nitrite. Nitrite interferes with the oxygen-carrying capacity of blood, so the oxygen you breathe in doesn't get distributed throughout the body. Symptoms, such as shortness of breath and blueness of the skin, can occur rapidly over a period of days.
Read more about Nitrate from the CDC

Infants are at the greatest risk for illness from exposure to high levels of nitrate.

  • Short-term: Excessive levels of nitrate in drinking water have caused serious illness and sometimes death. The serious illness in infants is due to the conversion of nitrate to nitrite by the body, which can interfere with the oxygen-carrying capacity of the child's blood. This can be an acute condition in which health gets worse rapidly over a period of days. Symptoms include shortness of breath and blueness of the skin.
  • Long-term: Researchers continue to explore if there are associations with long-term exposures to nitrate, including adverse reproductive effects and some cancers. The studies are not conclusive at this time, and health standards are focused on protecting infants.


It is recommend that every private well used for any drinking water purpose be tested annually for Nitrate. The local environmental health office can answer questions or assist with testing a private well for Nitrate.