Nearly 20% Of Americans Drink Water W. High Levels Of Nitrates; Possible Link To Cancer, Birth Defects Through Ag Runoff

Close to 20 percent of Americans are exposed to water polluted with high levels of potentially cancer-causing nitrates, known to come mostly from agricultural runoff, according to new research published this month. In a first-ever review of nitrate levels in public water systems across the country, the Environmental Working Group found that 6,114 of them—from heavily agricultural rural areas to major cities, including Los Angeles, Phoenix and Philadelphia—have elevated levels of nitrates, affecting 18 percent of the country’s population, or roughly one in five people, between 2021 and 2023. “

We wanted to get a full national picture,” said Anne Weir Schechinger, the report’s author. “And the sheer size of the numbers—there are over 62 million people impacted by this—I was not expecting that.” The government set the legal limit of nitrate in water at 10 milligrams per liter in the early 1960s to help prevent cases of “blue baby” syndrome, a condition in which infants have low levels of blood oxygen. But research has since found that concentrations at 5 milligrams per liter and even lower are linked to colorectal and other cancers, thyroid disease and birth defects. Health advocates have pushed for lowering the limit, but the Environmental Protection Agency has yet to do so. The Trump administration gutted the division that would continue a review process started under the Biden administration, Schechinger noted.

Wastewater discharges are a major source of nitrate pollution, but the most widespread source is agriculture, occurring when fertilizer used to grow feed for livestock or manure from concentrated animal feed operations, or CAFOs, seeps into groundwater or leaches into waterways. These two types of agricultural production often occur in close proximity, making CAFO-intensive areas especially exposed to nitrate pollution.

A recent study from Yale University researchers found that proximity to CAFOs was linked to increased cancer rates in three of the states with the most CAFOs—California, the country’s leading dairy state, Iowa, the country’s leading hog producer and Texas, the leading producer of beef. Nitrate-contaminated water, the researchers found, was a major risk. The states with the highest exposure to nitrate in drinking water are heavily agricultural, the EWG analysis found, and many of the highest levels of pollution were in agricultural areas in those states. Agriculture is a major industry in the states with the highest levels of nitrate-polluted water, the analysis found: California, Pennsylvania, Washington, Kansas, North Carolina, New York, Nebraska, Texas, Arizona and Wisconsin. While these states also happen to have higher numbers of public water systems, the prevalence of agriculture was clearly a factor, Schechinger said.

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https://insideclimatenews.org/news/27042026/agricultural-nitrate-water-pollution/