Nitrogen baby-blue syndrome

Nitrate (measured as Nitrogen) 10 10 "Blue baby syndrome" in infants under six months -life threatening without immediate medical attention. Symptoms Infant looks blue and has shortness of breath. Runoff from fertilizer use leaching from septic tanks, sewage erosion of natural deposits... 

In many countries there are strict limits on the permissible concentration of nitrate in drinking water and in many surface waters. The limit is 50 mg/1 of nitrate in the EU and 44 mg/1 in the United States (equivalent to 11.3 and 10 mg of nitrate nitrogen in 11, respectively). These limits are in accord with WHO recommendations established in 1970 and reviewed and reconfirmed in 2004 and ensure that drinking water will not cause methaemoglobinaemia, also known as blue-baby syndrome (see Section 6.6.1.2). For example, the permissible concentration of nitrate in bottled water for infants in the Czech Republic is only 15 mg/1. 

Pretty, J. N., and G. R. Conway. 1990. The Blue-Baby Syndrome and Nitrogen Fertilisers A High Risk in the Tropics. London IIED, pp. 4-5. 

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