Iowa is among a few states where cancer diagnoses are on the rise. A new analysis from the Harkin Institute for Public Policy & Citizen Engagement and the Iowa Environmental Council says that environmental exposures are partially to blame.
High pesticide and fertilizer use in the top corn-producing state, per- and polyfluoroalkyl substances (PFAS) in public drinking water supplies and elevated radon levels in soil and water threaten the health of residents and likely interact to drive up Iowa’s cancer rate, the second highest in the nation, the report’s authors say.
“These environmental risk factors are things that, by and large, we don’t have much ability to dramatically impact ourselves,” said Adam Shriver, director of wellness and nutrition policy at the Harkin Institute and one of the report’s lead authors. “They’re being imposed on the citizens of Iowa, really, without their input. And so it’s a basic fairness issue.”
Amid growing alarm over the far-reaching impacts of cancer in Iowa, the Harkin Institute and the Iowa Environmental Council launched an initiative last summer to explore the relationship between environmental risk factors and cancer rates in the state.
Pesticides, PFAS, nitrate and radon were the top environmental risk factors raised by a panel of scientific experts the organizations convened for the project. The finding echoed many of the same concerns expressed by attendees of “cancer listening sessions” held across the state last summer.
“I think we have enough evidence to convince us that there is something more than the traditional risk factors of obesity, smoking and alcohol use,” said Iowa state Rep. Austin Baeth, also a doctor practicing internal medicine in Des Moines. “And it’s in our environment. Because there’s really no other good reason why Iowa stands out in the nation as having the fastest-rising cancer rate.”
Radon is the second-leading cause of lung cancer in the United States, after smoking, and is the leading cause of lung cancer for people who have never smoked. Nearly a quarter of all cancer deaths in Iowa in 2026 are expected to be from lung cancer, the 2026 Cancer in Iowa Report by the Iowa Cancer Registry estimates.
While radon occurs naturally in Iowa soil, the remaining three environmental risk factors emphasized in the report are products and by-products of intensive agriculture and industrial manufacturing.
Iowa farms apply more than 60 million pounds of pesticides each year. Though that figure includes hundreds of compounds, the report focuses on the cancer risks of the three most commonly used chemicals in the state: acetochlor, atrazine and glyphosate.