How Nitrates End Up in Drinking Water Supplies

Excess nutrients from nitrogen- and phosphorous-based fertilizers, can leach into groundwater or seep into rivers and damage the aquatic life. 

Water high in nitrates, a compound that moves easily in water, can trigger blue baby syndrome in infants under 6 months old. The condition, if left untreated, can cause death.

Boiling the water won’t help. It further concentrates the contaminants. Dilution and filtering seem to be the best ways to limit exposure. 

"There are actually quite a few ways that nutrients or nitrogen compounds can end up in drinking water", says Andrew Ross, a water quality scientist with the Colorado Department of Public Health and Environment. Sources include everything from natural deposits in soil, to atmospheric nitrogen, to human activities.

“So that could be from sewage treatment, septic systems at homes, fertilizers on lawns, fertilizers on farms, livestock management,” Ross says.

Those last two – crop farms and livestock operations – are the biggest contributors to nutrient problems in the Gulf of Mexico. 

A 2008 study from U.S. Geological Survey scientists found corn and soybean farming in the Mississippi River watershed is the largest contributor of nitrogen in the Gulf, accounting for 52 percent of the nitrogen present.

Manure from livestock grazing on pasture is the biggest source of phosphorus, making up 37 percent, followed by corn and soybean farming at 25 percent.

Source: Net Nebraska