EPA Under Fire for Failing to Warn Public of Pesticide Cancer Risks

WASHINGTON, DC – March 30, 2026 – The U.S. Environmental Protection Agency, the nation's primary watchdog for environmental and public health, has systematically failed to require cancer warnings on pesticide products, even when its own scientists have identified significant cancer risks, according to two explosive new analyses released today. The reports, from the Center for Food Safety (CFS) and the Center for Biological Diversity (CBD), paint a stark picture of a regulatory system that allows chemicals linked to cancer to be sold to farmers and everyday consumers without the most basic information about their long-term health hazards.

The findings land just weeks before the Supreme Court is set to hear a landmark case that could fundamentally alter corporate liability and the power of the EPA to control pesticide labeling nationwide.

A Startling Discrepancy in Risk

The joint investigation reveals a chasm between the EPA's public safety goals and its regulatory actions. The agency’s official benchmark for acceptable cancer risk from pesticide exposure is a one-in-a-million chance over a lifetime. However, the Center for Food Safety's analysis found that the EPA has approved pesticides with cancer risks as high as one in every 100 people exposed—a risk level 10,000 times greater than its own standard.

Over the past four decades, the EPA has classified nearly 200 different pesticide active ingredients as either "likely" or "possible" human carcinogens. Yet, according to the Center for Biological Diversity's review of over 93,000 pesticide labels, the agency has mandated cancer warnings on a minuscule fraction of these products. Only 1.4% of products containing a "likely" human carcinogen and just 1.1% of those with a "possible" human carcinogen carry an explicit cancer warning.

"It's bad enough that the EPA approves cancer-causing pesticides," said Bill Freese, science director at the Center for Food Safety, in a statement. "But if the agency is going to allow such chemicals to be freely sold at Home Depot, Wal-Mart and farm-supply stores, the very least the EPA must do is require a clear cancer warning on the label. Warnings save lives by incentivizing users to wear protective equipment that reduces risk."

Lori Ann Burd, environmental health program director at the Center for Biological Diversity, expressed similar alarm. "It's dumbfounding that the EPA has failed to require any cancer warning on thousands of pesticide products sold to the public that the agency itself has linked to cancer," she stated. "Why should anyone have confidence in the EPA's ability to keep tabs on the pesticide industry and protect us all from harmful poisons when it won't even compel companies to put long-term health warnings on pesticides it knows are really dangerous?"

Unseen Dangers on Store Shelves and Dinner Plates

For most Americans, this regulatory gap means potential exposure to carcinogens without their knowledge. The analyses found that the vast majority of existing cancer warnings on pesticides are not the result of federal action but are mandated by California's Proposition 65, a state law that requires warnings for chemicals known to cause cancer or reproductive harm. This leaves consumers in the other 49 states without the same information.

For example, pesticides containing active ingredients like mancozeb, diuron, and chlorothalonil are all designated by the EPA as "likely" human carcinogens. These chemicals are widely used on fruits, vegetables, and grains across the country. Yet, outside of California, their labels are not required to mention the cancer risk identified by the very agency that approved their use.

The CFS report highlights even more specific, alarming examples from the EPA's own data. It found that the agency predicts drinking water contaminated with the pesticide thiophanate-methyl can cause cancer in up to four in 10,000 people. For other registered pesticides, residential and occupational use can pose a cancer risk to as many as seven in 1,000 people—a staggering 7,000 times higher than the EPA's one-in-a-million threshold.

A High-Stakes Legal Showdown

The timing of these revelations is critical. On April 27, the Supreme Court is scheduled to hear oral arguments in Monsanto Company v. John L. Durnell. The case centers on glyphosate, the active ingredient in Roundup, which thousands of plaintiffs claim caused their non-Hodgkin's lymphoma. Monsanto, now owned by Bayer, argues that it cannot be sued under state laws for failing to put a cancer warning on Roundup because the EPA approved the product's label without one.

This defense rests on the legal doctrine of federal preemption, which posits that federal law—in this case, the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA)—overrides state law. The company's position is that if the EPA is the sole arbiter of label content, then manufacturers should be immune from state-level lawsuits demanding different or additional warnings. A victory for Monsanto could effectively shield the entire pesticide industry from liability for failing to warn consumers about known health risks, as long as they have an EPA-approved label.

Conversely, if the court sides with Durnell, it would affirm the rights of individuals to sue companies for damages under state laws, preserving a crucial avenue for corporate accountability. The case forces a difficult question: Does the EPA's approval of a label represent a scientific ceiling for safety information, or is it merely a regulatory floor, with manufacturers still holding a separate duty to warn consumers of dangers they are aware of?

The new analyses from CFS and CBD add a potent layer to this debate, suggesting that relying solely on the EPA's labeling decisions has left the public dangerously uninformed. As the Supreme Court prepares to weigh in, the outcome will have profound consequences, determining not only the future of pesticide litigation but the fundamental right of the American public to know about the risks of the chemical products they use every day.