Iowa’s midterm campaigns have brought a long-simmering issue to the fore: the state’s polluted waterways and elevated cancer rates. For decades, the topic was politically sensitive because it implicated the state’s powerful agricultural industry, a major producer of corn, soybeans, and hogs. Chemical fertilizers and animal waste carry nitrates and phosphorus into rivers, and the Des Moines area has faced repeated water-use restrictions as a result.
Iowa now has the second-highest rate of newly diagnosed cancers in the country, with prostate, breast, and lung cancer increasing faster than the U.S. average. New state-funded research at the University of Iowa finds that demographic and behavioral factors explain most—but not all—of the above-normal rates for five cancers. Researchers are now examining environmental factors, including nitrate levels, though the EPA does not currently classify nitrates as a cancer risk.
Candidates are responding in different ways. Democrat Josh Turek, running for U.S. Senate, directly links tap water and nitrates to cancer. His Republican opponent, Ashley Hinson, says treated water meets federal regulations and calls for more investment in infrastructure and conservation. In the governor’s race, Republican Zach Lahn has broken with many peers by connecting agrochemicals to the cancer crisis, while Democrat Rob Sand also prioritizes the issue. Both stop short of mandating conservation practices.
There is broad agreement that water quality is a serious problem, but the parties differ on how to address it. Republicans emphasize voluntary programs and infrastructure funding, while Democrats are more willing to point at agricultural pollution. The EPA’s nitrate review has stalled under successive administrations, leaving the scientific and regulatory questions unresolved.