The journal Regulatory Toxicology and Pharmacology has retracted a paper from the year 2000 asserting the safety of glyphosate—the active ingredient in the herbicide Roundup—which has been relied upon as a hallmark piece of evidence for regulatory approvals of the agricultural chemical since its publication.

In recent years, Roundup has faced increasing public scrutiny due to its potential adverse health effects like cancer, and Bayer’s Monsanto, the maker of Roundup, has been mired in lawsuits alleging harm from exposure to the chemical. Bayer announced in 2021 that it would end sales of glyphosate-based herbicides in the U.S. to manage litigation risks, because, at the time, more than 40,000 related lawsuits had been filed by cancer patients or their families against the company.

According to the retraction, such lawsuits have uncovered emails from Monsanto showing that employees of the company may have contributed to the data collection, writing, and review of the 2000 study without acknowledgement. Further correspondence with Monsanto revealed during litigation also indicates that the authors may have received undisclosed financial compensation from Monsanto for their work.

“This lack of transparency raises serious ethical concerns regarding the independence and accountability of the authors of this article and the academic integrity of the carcinogenicity studies presented,” states the retraction.

EPA Due to Deliver Decision on Glyphosate Safety in 2026

The U.S. Environmental Protection Agency (EPA) is due to deliver a safety reevaluation decision for glyphosate in 2026 following a lawsuit filed by the Center for Food Safety (CFS) and its allies challenging the agency’s determination that glyphosate is safe for humans and the environment. In 2022, the U.S. Court of Appeals for the Ninth Circuit overturned EPA’s safety decision, finding that the agency did not adequately consider the chemical’s risk of harm to humans or to endangered species in compliance with the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). At the time, the court ordered the completion of a new assessment by October 2022, which EPA said it could not meet, forcing the agency to withdraw its previous decision. This required EPA to draft and issue a new, complete, FIFRA-compliant glyphosate final registration review decision, which is expected to be completed in 2026.

Evidence of Glyphosate’s Carcinogenicity and Genotoxicity

The World Health Organization’s International Agency for Research on Cancer (WHO’s IARC) declared in 2015 that glyphosate is “probably carcinogenic to humans.”

Investigating WHO IARC’s conclusion, in 2025, a major rodent study was published in Environmental Health finding that glyphosate causes multiple types of cancer, such as leukemia, even at or below doses considered “safe” by EU regulatory agencies (specifically, the EU’s Acceptable Daily Intake level and No Observed Adverse Effect Level). Over two years, thousands of rats were exposed to glyphosate in utero via drinking water ingested by their mothers, and then through drinking water throughout 104 weeks of life. Statistically significant dose-related increases of various types of malignant tumors were observed. The findings were consistent with WHO’s conclusion, as well as other epidemiological evidence on the chemical’s carcinogenicity. The study was led by the Ramazzini Institute as part of the Global Glyphosate Study, with collaboration from institutions like Boston College and Mount Sinai.

In addition to glyphosate exposure resulting from direct contact, such as agricultural workers who have applied the chemical to crops, pesticide residues may be present in food and water consumed by the general population. Biomonitoring studies have found the widespread presence of glyphosate in U.S. adults’ and children’s urine.