Iowa Farmers Face Nitrate Standards as Cancer Concerns Rise

A 1945 medical report linked nitrate pollution in farm water to a deadly infant condition.

Dr. Hunter H. Comly documented the first case of "blue baby syndrome" in the Journal of the American Medical Journal. The infant, born healthy at eight pounds and eight ounces, developed vomiting and diarrhea. Doctors initially suspected a milk allergy. The baby’s skin turned blue due to a lack of oxygen in the blood. Comly identified high nitrate levels in the well water used to mix the formula as the cause.

The condition, methemoglobinemia, affected the protein responsible for delivering oxygen in red blood cells. Doctors treated the infant with methylene blue, a synthetic dye. The father brought a water sample to the hospital after suspecting the well water was the culprit. Comly’s report noted that the admitting physician welcomed this theory despite initial skepticism. Subsequent tests confirmed the presence of large amounts of nitrates in the water.

Comly recommended that well water used for infant feeding contain no more than 10 to 20 parts per million of nitrate-nitrogen. This figure became the basis for future regulations. In 1962, the U.S. Public Health Service established the first national nitrate drinking water standard. They adopted the 10 mg/L limit proposed by Comly. The standard remains in place today.

In Iowa, the source of much of the early data, water is treated to meet this standard. The state hosts nearly 11,000 factory farms that generate more than 170 billion pounds of manure. Synthetic fertilizers and manure runoff continue to introduce nitrates into the water supply. Residents are now linking rising cancer rates to this exposure. Many view the state’s cancer statistics as a crisis requiring action from lawmakers and researchers.

The current administration has paused efforts to reevaluate the nitrate standard. The office originally tasked with this scientific review has been shuttered. The U.S. Environmental Protection Agency stated that the work was largely transitioned to a different office. They concluded that the existing nitrate standard is not a candidate for revision. This decision has drawn criticism from environmental groups.

Michael Schmidt, general counsel for the Iowa Environmental Council, argues that the standard needs further study. He noted that blue baby syndrome is a short-term effect, while cancer risk is linked to long-term exposure. Research suggests that elevated nitrate levels over time increase cancer risk. Schmidt believes the current limit does not fully account for these extended health impacts.

Historical data supports the link between nitrate levels and infant health. A 1951 literature survey by Graham Walton found that hundreds of infants had been diagnosed with the condition, and 39 had died. In Minnesota, 139 cases of methemoglobinemia were recorded between 1947 and 1949, resulting in 14 deaths. Walton’s report highlighted that 83 of 129 wells involved in these cases were located within 50 feet of a barnyard, pigpen, privy, or cesspool.

The agriculture industry has long been tied to nitrogen pollution. Comly’s 1945 report noted that wells near barnyards and pit privies were most likely to cause cyanosis in infants. Edwin Schmidt, a 1956 researcher, found that soils contaminated with organic nitrogen from livestock had the highest nitrifying capacities. Despite these findings, farmers increasingly relied on nitrogen fertilizers and animal feedlots in the mid-20th century. Local newspapers in Illinois and Minnesota warned parents to test their well water for nitrates during this period.