Designed to provide vital nutrients for growing crops, nitrate-infused fertilizers dumped on fields across the United States may actually be killing people.

The chemicals seep into rural water supplies where tiny amounts are dangerous for infants and increase the risk of various cancers in adults, according to a report from the Environmental Working Group (EWG). The report found that water systems serving 200 million Americans in 49 states contain some level of contamination.

Many of the 672 residents of Pretty Prairie, Kansas, farm massive fields of wheat, corn, and soybeans, but after a tough day in the fields, they can’t even trust their taps to safely quench their thirst. That’s because, for more than two decades, their water has contained an unsafe level of nitrate, which has been linked to cancer, that has seeped into the water system from the fields.

The nitrates found in fertilizer have long been linked to “blue-baby syndrome,” a deadly condition that restricts the amount of oxygen delivered through a baby’s bloodstream. The infant’s skin takes on a blue tint because of the reduced oxygen, especially around the fingers, earlobes, and lips where skin is thinner.

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Researchers connected nitrate to blue-baby syndrome more than fifty years ago, prompting the United States Environmental Protection Agency to limit the acceptable level of nitrate in water to 10 parts per million (ppm) in 1962.

But the U.S. Geological Survey found that nitrate levels exceeded 10 ppm in 4.4% of wells in the United States in 2004. In agricultural areas, like Pretty Prairie, nitrate levels are even higher at 7%, EWG reports.

According to studies by the National Cancer Institute, nitrate levels above just 5 ppm increase risk for colon, kidney, and stomach cancers. The EWG report found that 650 towns surrounded by farmland had nitrate levels above 7 ppm — 118 towns of those towns had levels that surpassed the 10 ppm limit set by the EPA.

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Instead of holding the massive agricultural companies that dominate American farming accountable, federal regulators compelled Pretty Prairie to build a $2.4 million water treatment facility. Though such projects make water safer, they place a huge financial strain on small communities. In January, the federal government denied Pretty Prairie a major grant that would have helped construct the water facility, so the facility has yet to be built. In the meantime, the town continues to provide bottled water to residents.

Existing federal programs pay farmers to adopt safer pesticide and fertilizer strategies and water protection tactics, but these efforts have not reached many of the places plagued by nitrate run-off, EWG says.  

“Farmers can take often simple steps to keep fertilizer and manure out of drinking water sources,” EWG Senior Vice President Craig Cox said in a statement. “But far too few farmers are taking action and federal farm policy doesn’t do enough to help them. The result is that rural Americans are burdened with the health risks and cleanup costs of unchecked farm pollution, when it makes more sense to keep nitrate and other contaminants from getting in the water in the first place.”


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Water in Hundreds of US Towns Contains Cancer-Linked Chemical, Report Finds

By David Brand