A major scientific paper, used for over two decades by regulators and Monsanto to assert the safety of its Roundup weedkiller, has been formally retracted by a leading journal due to "serious ethical concerns" about its authorship and integrity.
The Ghostwriting Scandal Uncovered
The paper, titled Safety Evaluation and Risk Assessment of the Herbicide Roundup and Its Active Ingredient, Glyphosate, for Humans, was published in the year 2000 in the journal Regulatory Toxicology and Pharmacology. It concluded that glyphosate herbicides posed no cancer, reproductive, or developmental risks to humans.
Authored by three external scientists—Gary Williams, Robert Kroes, and Ian Munro—it was presented as independent validation. However, internal Monsanto emails revealed during US cancer litigation showed the company's deep involvement in its creation.
One email from Monsanto official Lisa Drake in May 2000 praised the "hard work" of seven Monsanto employees over three years of "data collection, writing, review and relationship building with the papers’ authors". Another email from scientist William Heydens in 2015 explicitly referenced ghostwriting the 2000 paper, suggesting paying outside scientists to "edit & sign their names" to company-prepared work.
Regulatory Reliance and Legal Fallout
For years, global regulators, including the US Environmental Protection Agency (EPA), cited the study as evidence of glyphosate's safety. The journal's editor-in-chief, Martin van den Berg, stated the retraction was due to concerns over author independence and the paper's reliance solely on unpublished Monsanto studies while ignoring other published research.
The retraction comes amidst ongoing legal battles where plaintiffs have won billions in damages, claiming Roundup caused their non-Hodgkin’s lymphoma. Lawyer Brent Wisner, who helped reveal the internal documents, called the study "the quintessential example" of how companies can undermine peer-review through ghostwriting and bias.
Official Responses and the Path Forward
In response, Bayer, which bought Monsanto in 2018, stated that Monsanto's involvement was acknowledged in the paper's credits and reiterated that global regulators deem glyphosate safe. The EPA said it was aware of the retraction but had never relied solely on that article, citing its review of over 6,000 studies. Its updated assessment, due for public comment in 2026, will not use the retracted work.
The retraction marks a significant moment in the long-running controversy, highlighting the critical issue of corporate influence in scientific literature that shapes public health policy worldwide.
