WHAT NITRATE-NITROGEN LEVELS ARE SAFE OR DESIRABLE?
The maximum safe level of nitrate-nitrogen in drinking water is 10 milligrams per liter (commonly written as “mg/l, and synonymous with “parts per million”). The equivalent of 10 milligrams of nitrate-nitrogen, expressed as NO3 nitrate, is 50 mg/l. Levels above this can affect an adult, and could potentially lead to a fatal blood disorder in infants under six months of age. Both the World Health Organization of the United Nations, and US and state regulations, recommend a MAXIMUM nitrate-nitrogen level no higher than 10 mg/l. The ideal level in human drinking water for nitrate-nitrogen or nitrate is 0 mg/l. WHAT ARE THE BIGGEST RISKS? Infants Methemoglobinemia, commonly known as ‘blue baby syndrome,’ can occur in infants under six months if nitrate-nitrogen levels are greater than 10 mg/l. Physiologically, nitrates are reduced to nitrites in the stomach. Nitrite enters the bloodstream and binds to hemoglobin, changing it to methemoglobin. The effect is interference with the blood’s abi
