Nitrates (NO3) are inorganic chemicals dissolved in some water supplies as a result of feedlot and agricultural activities. Nitrate levels over 45 mg/L as actual NO3 (or 10 mg/L as Nitrogen, N) can be a serious health risk to infants and children.
According to the CDC, nitrate is a compound that is formed naturally when nitrogen combines with oxygen or ozone. Nitrogen is essential for all living things, but high levels of nitrates in water can be dangerous to health, especially for infants and pregnant women. Nitrates are also made in large amounts by plants and animals, and are released in smoke and industrial or automotive exhaust.
Nitrates may be successfully removed from water using treatment processes such as ion exchange, distillation, and reverse osmosis. For more information regarding removal of nitrates see Reverse Osmosis.