Nitrate

NITRATE is one of the most common groundwater contaminants in rural areas. It is regulated in drinking water primarily because excess levels can cause methemoglobinemia, or "blue baby" disease. Although nitrate levels that affect infants do not pose a direct threat to older children and adults, they do indicate the possible presence of other more serious residential or agricultural contaminants, such as bacteria or pesticides. Nitrate gets into water from fertilizer runoff, manure from large animal feeding operations and wastewater treatment plant effluent. Independent data shows that detectable levels of nitrate are present in the water served to over 218 million Americans. Tap water in agricultural areas frequently has the highest nitrate concentrations. Private drinking water wells in the vicinity of animal farms and intensely fertilized fields, or in the locations where septic tanks are commonly used, can also have unsafe levels of nitrate.