Nitrate contamination of potable water sources is becoming one of the most important water quality concerns in California and across the United States. The maximum contaminant level (MCL) for nitrate is 45 mg/L as nitrate (NO3-), which is approximately equivalent to 10 mg/L as nitrogen (N). The major health concern of nitrate exposure through drinking water is the risk of methemoglobinemia, or “blue baby syndrome,” especially in infants and pregnant women. Due to the nature of the infant digestive system, nitrate is reduced to nitrite which can render hemoglobin unable to carry oxygen (SWRCB 2010).

Website: https://ucanr.edu/sites/groundwaternitrate/files/139107.pdf