Nitrate nitrogen is a commonly used lawn and agricultural fertilizer.  It is a chemical formed in the decomposition of waste materials, such as manure or sewage.  If infants less than six months of age are drinking water (or formula made with water) that contains more then 10 ppm nitrate nitrogen, they are susceptible to methemoglobinemia.  This disease interferes with the blood's ability to carry oxygen.  Recent studies also suggest that high nitrate water may be linked to birth defects and miscarriages.  High nitrate levels also suggest that other contaminants might be present.

Acceptable results:  10 ppm or less

Sources:  Fertilizer, septic system effluent and animal waste.  In most cases, elevated nitrate levels indicate general contamination of the aquifer at the depth of the well.

Recommended testing:  Annually