Iowa now records the second-highest rate of new cancer diagnoses in the United States, trailing only Kentucky, and is one of only a handful of states where the rate is still climbing while the national rate falls. Much of the public debate has centered on the state’s intensive agriculture — and, increasingly, on glyphosate, the world’s most widely used herbicide. But a February 2026 federal executive order has complicated any move to restrict the chemical, declaring it critical to national security and shielding its producers from certain liability. The result is a widening gap between mounting health concerns and the legal and economic barriers to acting on them.

Background

According to the Iowa Cancer Registry’s 2025 report, Iowa remains second in the nation for age-adjusted cancer incidence, with an estimated 21,200 new diagnoses and about 6,300 deaths projected for the year. The state’s rate ran more than 10 percent above the national average for the 2017–2021 period, and its rate among people under 50 also exceeds the national figure. Iowa began diverging from national cancer trends around 2013.

Researchers have been candid that no single cause explains the pattern. Mary Charlton, director of the Iowa Cancer Registry, has said cancer is complex and multifactorial, pointing to high binge-drinking rates, persistent smoking, low physical activity and statewide radon exposure alongside environmental factors. In simple terms: many risk factors stack on top of one another, and isolating any single one is difficult.

Agriculture is nonetheless a focus. Roughly 85 percent of Iowa’s land is used for crops or animal agriculture, and the state ranks among the top five nationally for industrial pesticide use. A March 2026 report from the Iowa Environmental Council and Drake University’s Harkin Institute — drawing on 29 experts and dozens of public listening sessions — examined four environmental risk factors: pesticides, nitrate, PFAS and radon. It identified glyphosate, atrazine and acetochlor as the state’s three most-applied pesticides.

The Policy: What the Federal Order Does

Glyphosate — the active ingredient in Roundup, originally developed by Monsanto and now owned by Bayer — sits at the center of a contested regulatory picture. In 2015, the World Health Organization’s International Agency for Research on Cancer classified it as “probably carcinogenic to humans.” The U.S. Environmental Protection Agency and the European Food Safety Authority have said they found no such link. The EPA is due to issue a reevaluation of glyphosate’s safety in 2026 following litigation. In simple terms: major scientific and regulatory bodies disagree on how dangerous it is.

On February 18, 2026, President Trump signed an executive order invoking the Defense Production Act of 1950 to declare domestic production of glyphosate-based herbicides and elemental phosphorus — a key input — critical to national security and the food supply. The order directs the Secretary of Agriculture to prioritize and allocate production, and it includes a clause conferring immunity under Section 707 of the Act to producers that comply with the order.

The order’s central argument is dependency. It states there is “no direct one-for-one chemical alternative” to glyphosate-based herbicides and that losing access would jeopardize agricultural productivity and the food supply. This is the practical obstacle to an outright ban: not a claim that Iowa’s soil itself prevents regulation, but that the U.S. farm system has been built around the chemical with no ready substitute at national scale.

How It Is Playing Out

The tension is unfolding on several fronts at once. One day before the executive order, Bayer proposed a $7.25 billion settlement to resolve current and future claims alleging glyphosate causes cancer; the company admits no liability and maintains the product is safe when used as directed. In January 2026, the journal Regulatory Toxicology and Pharmacology retracted a 2000 paper asserting glyphosate’s safety that had underpinned regulatory approvals for years.

Politically, the order split the administration’s own base. Health and Human Services Secretary Robert F. Kennedy Jr. backed it, warning that an abrupt ban could put a large share of farmers out of business, while “Make America Healthy Again” advocates who had campaigned against glyphosate condemned the liability shield. Republican Rep. Thomas Massie of Kentucky introduced legislation he says would undo the order.

Impact

For Iowans living amid the state’s cancer surge, the federal action narrows the near-term options. State and local governments face a separate constraint: a draft 2026 farm bill would mandate uniform national pesticide labeling, preempting states from requiring their own warnings. Combined with the executive order’s production mandate and liability clause, the effect is to concentrate authority over glyphosate at the federal level while litigation and settlement talks continue.

Independent research on agricultural exposure is ongoing. The National Cancer Institute’s decades-long Agricultural Health Study, which follows tens of thousands of pesticide applicators in Iowa and North Carolina, has found associations between certain farm chemicals and certain cancers, but its researchers caution that establishing causation for specific exposures takes years of additional follow-up.

Analysis

The competing claims come down to two definitions of security. The executive order treats uninterrupted access to glyphosate and phosphorus — with only one domestic producer — as a strategic asset to be protected from foreign supply shocks. Critics, including some regenerative-agriculture advocates, argue that genuine security lies in soil health, clean water and reduced chemical dependence. Both sides broadly agree on one point that complicates any ban: after decades of use, the conventional farm system has limited capacity to pivot quickly.

For Iowa specifically, the science remains unsettled. Glyphosate is one of several environmental factors under study, and the registry’s own experts resist attributing the state’s rates to any single agent. That scientific caution, paired with the new federal protections, makes sweeping regulatory action unlikely in the short term even as public concern grows.

Conclusion

Iowa’s cancer numbers have made it a national test case for how environmental and agricultural exposures are studied and regulated. Glyphosate has become the most visible flashpoint in that debate — but it is neither the sole suspect the science identifies nor a chemical the federal government is currently prepared to restrict. With a 2026 EPA reevaluation, a pending Supreme Court case, a contested farm bill and a multibillion-dollar settlement all in motion, the coming year is likely to determine how much room states like Iowa have to act.

Key Takeaways

• Iowa has the second-highest cancer incidence in the U.S. (behind Kentucky) and is one of only a few states where the rate is rising.
• Researchers stress the cause is multifactorial; glyphosate is one of several environmental risk factors under study, not an established sole cause.
• A February 18, 2026 executive order declared glyphosate and elemental phosphorus critical to national security, invoking the Defense Production Act and shielding producers from certain liability.
• The order’s core rationale is that there is no one-for-one substitute for glyphosate — the real obstacle to a ban, rather than any soil-specific claim.
• Parallel developments — the EPA reevaluation, Bayer’s $7.25B proposed settlement, a draft farm bill and Rep. Massie’s counter-bill — will shape the outcome in 2026.

Sources

Iowa Cancer Registry, “Cancer in Iowa 2025” annual report (Feb. 25, 2025).

Iowa Environmental Council & The Harkin Institute, Drake University, “Environmental Risk Factors and Iowa’s Cancer Crisis” (March 2026).

Investigate Midwest / Sentient Media, coverage of the Iowa environmental cancer report (March 2026).

PBS NewsHour, “As cancer rates fall nationally, Iowa sees a troubling rise in diagnoses” (2026).

The White House, Executive Order and Fact Sheet, “Promoting the National Defense by Ensuring an Adequate Supply of Elemental Phosphorus and Glyphosate-Based Herbicides” (Feb. 18, 2026).

CNN Health, glyphosate and MAHA coverage (Feb. 24, 2026); Food Safety Magazine (Feb. 23, 2026); Chemical & Engineering News (March 3, 2026).

International Agency for Research on Cancer (IARC), Monograph Vol. 112 (2015).