In Johnson County, cancer rates for people under 50 are climbing faster than in the general population, with colorectal, uterine, kidney, and leukemia cases on the rise, according to a study conducted by the Iowa Environmental Council and the Harkin Institute for Public Policy & Citizen Engagement.

Colleen Fowle, water program director for the Iowa Environmental Council, said for people under 50, rates rose faster than the general population, most notably in those four types of cancer. Fowle noted a link between nitrates and pesticides commonly found in Iowa groundwater. 

“We see that the same types of cancer linked to those pollutants are the cancers that are rising in people under 50 in Iowa,” Fowle said.

Johnson County Supervisor Lisa Green-Douglass said the county can’t do anything about agricultural runoff.

“The state has tied the hands of local governments to not only monitor but to have any kind of authority on agriculture at all. We can’t regulate what happens in [agriculture] land in Johnson County,” Green-Douglass said. 

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Iowa Code explicitly prohibits local governments from adopting or enforcing local legislation related to “the use, sale, storage, transportation, disposal, formulation, labeling, registration, or manufacture of fertilizer or soil conditioners.”

Johnson County has prioritized obtaining data on water quality, Green-Douglass said, with the state pulling back funding this year.

“The county is paying for one more year of a sensor. It’s like $200,000 per sensor, with the help of the conservation department, pulled together some money so that we could continue that monitoring,” Green-Douglass said. 

Iowa’s statewide monitoring network, the Iowa Water Quality Information System, lost its dedicated state funding after lawmakers redirected roughly $500,000 from its annual budget to the Department of Agriculture and Land Stewardship in 2023, according to the Iowa Environmental Council. 

The system uses real-time sensors to track pollutants in rivers and streams, but relies now on temporary local and partner funding. The network secured donor funding following the legislation that has allowed the sensor network to remain in operation through June 2026, according to the council. 

Over the last three years, Johnson County has participated in many efforts to support water and soil quality, including joining the Middle Iowa Watershed Management Authority — coordinated regional water resources management — as well as two soil quality programs, the Soil Quality Restoration program and the Pocket Prairie grant program. 

“The effects prairie plants have on the soil, it makes the soil very, very healthy, so that then water from heavy rains that filters through there ends up cleaner water,” Green-Douglass said. 

Fowle said one of the reasons for the study was ample conversation about lifestyle risk factors, and researchers wanted to specifically explore environmental risk factors. Even before starting the study, during listening sessions, Fowle said Iowa residents were “hungry” for information about cancer in Iowa.

“More and more people became interested and started reaching out,” Fowle said. “We heard that people were very concerned about their risk factors for cancer and how they could take personal ownership and reduce them, but they didn’t feel like they had enough information about environmental risk factors in order to adequately reduce their risk.”

Johnson County is more divided on opinions about Iowa’s cancer rates, Green‑Douglass said, with rural residents claiming they take proper precautions, while other residents express greater concern.

Fowle said this rise in cancer for people under 50 is concerning due to the way it affects patients even after treatment.

“We know that even if you survive cancer, it makes your other health challenges even more challenging. There’s a lot of continuing care that cancer survivors have to go through,” Fowle said.

Depending on the cancer site, Fowle said there’s a significant difference between the Iowa and the U.S. rates. According to the study, Iowa has a higher cancer rate than the U.S. in every form of cancer except four: stomach, ovary, all sites for children under 15, and all sites for children under 20.

Fowle said an easy first step for Iowa to take is to adopt the U.S. Environmental Protection Agency’s health criteria set in 2016.

The EPA sets health-based limits for chemicals in water, including carcinogens, to protect public health. Its 2016 update lowered recommended levels based on newer research, but Iowa has not yet adopted these standards, leaving state regulations less strict than federal guidance.

Fowle said one of the major concerns is how many cancer risk factors Iowans are exposed to, including nitrates, high use of pesticides, and contamination of PFAS — persistent, toxic industrial chemical compounds.

“We have an oncologist explain it to us as he sees it, as kind of like a bank of light switches, and you have to have several light switches turned on in order to receive a cancer diagnosis,” Fowle said. “So what we’re doing in our environment is we’re basically turning on all the switches.”

Jamie Gade, Johnson County Public Health social determinants of health coordinator, said establishing cancer causation can be difficult when so many factors can contribute, with a parent passing down a breast cancer gene or nitrate exposure.

“Twnety years ago, you had some water with super high nitrates or other things in it that then later you moved somewhere else, and you got cancer later on because that water you drank 20 years ago every single day for like five years,” Gade said.

While the study’s focus is environmental, Gade encouraged people to take action with lifestyle factors, with cancer likelihood increasing if the individual never exercises, doesn’t eat fruits and vegetables, binge drinks, or smokes.

According to national statistics, Iowa is below average on multiple health behaviors, with Iowa being 48th — meaning the worst behavior — for binge drinking, 43rd for exercise, and 31st for consumption of fruits and vegetables, according to America’s Health Rankings.

While Iowa has higher cancer incidence rates, Gade said Iowa’s mortality rate is similar to the rest of the U.S. 

“That’s kind of showing that people are getting the treatment that they need earlier than. I think it’s potentially more screening, which is great,” Gade said.

For those who feel alarmed at the results of the study, Gade encourages them to check the radon levels at their homes and get screened for cancer.