The MCL for nitrate is 10.0 ppm (10.0 grams per million grams of water).
Nitrate in drinking water at levels above 10.0 ppm is a health risk for infants of less than six months of age.
High nitrate levels in drinking water can cause blue baby syndrome.
Nitrate levels may rise quickly for short periods of time because of rainfall or agricultural activity.
If you are caring for an infant, you should ask advice from your health care provider.