New Analyses: EPA Consistently Fails to Warn Public of Pesticide Cancer Risks

WASHINGTON, March 30, 2026 /PRNewswire/ -- The Environmental Protection Agency has routinely failed to put cancer warnings on pesticide products even when its own assessments have found a high risk of those products causing cancer, according to two new analyses released today by the Center for Food Safety and the Center for Biological Diversity.

The Center for Food Safety analyzed the level of risk the EPA permitted for both currently approved and legacy pesticide active ingredients. The analysis found that pesticides have been allowed on the market with a cancer risk as high as one in every 100 people exposed, a far greater level than the EPA's benchmark of a one in a million chance of developing cancer. Over the last 40 years, the EPA has approved 200 active ingredients that are "likely" or "possible" carcinogens.

The Center for Biological Diversity analysis examined pesticide product labels for all currently approved pesticide products. The EPA has instituted cancer warnings on only 69 of 4,919 pesticide labels (1.4%) containing an active ingredient that the agency has designated a "likely" human carcinogen. And the agency has instituted cancer warnings on just 242 of the 22,147 pesticide labels (1.1%) that contain an ingredient the agency has designated as a "possible" human carcinogen.

"It's bad enough that the EPA approves cancer-causing pesticides," said Bill Freese, science director at the Center for Food Safety. "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."

"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," said Lori Ann Burd, environmental health program director at the Center for Biological Diversity. "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?"

These new analyses come before the April 27 oral arguments in the Supreme Court case Monsanto Company v. John L. Durnell. Monsanto, since acquired by Bayer, is seeking substantial immunity from future lawsuits brought by Americans who used glyphosate-based products like Roundup and contracted rare cancers that numerous studies have linked to the pesticide. The case hinges on whether the EPA has sole authority to implement pesticide label warnings.

Both analyses found that the vast majority of cancer warnings on pesticides come from obligations under Proposition 65 in California, which requires warnings on products, including pesticides, that contain hazardous levels of chemicals linked to cancer, birth defects or reproductive harm. However, most Americans are not adequately warned about products' known cancer risks.

For instance, pesticide products containing mancozeb, diuron and chlorothalonil — three EPA-designated "likely" human carcinogens — are only required to include a cancer warning in the state of California. The pesticides are applied to a wide range of vegetable, fruit and grain crops grown in many other states, according to U.S. Geological Survey reports.

Full Summary of Analyses

The Center for Food Safety analysis focused on the active ingredients contained in currently approved and legacy pesticide products. It found that of the 570 unique pesticide chemicals that the EPA's Office of Pesticide Programs has analyzed for carcinogenic potential since 1985, more than a third (35%) are either "likely" human carcinogens (73) or "possible" human carcinogens (127).

For many of these pesticide ingredients the EPA has identified substantial cancer risks far exceeding its policy threshold of preventing a cancer risk of greater than one in 1 million people exposed.

For example, the EPA predicts drinking water contaminated with the pesticide thiophanate-methyl can cause cancer in up to four in 10,000 people exposed. Residential and occupational uses of other registered pesticides can cause cancer in as many as seven in 1,000 people exposed, a 7,000-fold higher risk than the EPA's threshold for unacceptable cancer risk.

The Center for Biological Diversity analysis focused on the pesticide labels of individual pesticide products and reviewed more than 93,000 historic and currently approved pesticide labels for all products now available to pesticide users. It found that the EPA has instituted cancer warnings on only 69 of 4,919 pesticide labels (1.4%) containing an ingredient that the agency has designated a "likely" human carcinogen and 242 of the 22,147 pesticide labels (1.1%) that contain an ingredient the agency has designated as a "possible" human carcinogen.

In the few instances when the EPA has instituted a cancer warning on pesticide labels, implementation can be haphazard and confusing. For instance, the agency has implemented cancer warnings on some products containing triphenyltin hydroxide. However other products with the same amount of active ingredient and approved for the same uses contain no cancer warning at all.

The Center for Biological Diversity is a national, nonprofit conservation organization with more
than 1.8 million members and online activists dedicated to the protection of endangered species
and wild places.

Center for Food Safety's mission is to empower people, support farmers, and protect the earth
from the harmful impacts of industrial agriculture. Through groundbreaking legal, scientific, and
grassroots action, we protect and promote your right to safe food and the environment. Please
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SOURCE The Center For Food Safety