When a government agency decides whether a chemical in your food is safe, where does the science come from? Most of us assume it’s independent. In the case of Roundup — the world’s most widely used weedkiller — the manufacturer wrote the research, and it went unchallenged for 25 years.

In 2000, a study published in the journal Regulatory Toxicology and Pharmacology concluded Roundup posed no health risk to humans. But internal Monsanto emails released in 2017 litigation revealed company employees had ghostwritten the paper. Despite that, it remained in the scientific record, cited without caveat in hundreds of academic papers and dozens of government documents worldwide.

Harvard historian of science Naomi Oreskes and researcher Alexander Kaurov changed that. Their 2025 analysis found the ghostwritten paper ranked in the top 0.1% of all cited glyphosate literature. They requested the journal retract it. In November 2025, it did, citing “serious ethical concerns.” Oreskes and Kaurov also wrote about their findings in Undark.

The retraction comes as Bayer, which acquired Monsanto in 2018, faces roughly 65,000 Roundup cancer lawsuits. On February 17, the company proposed a $7.25 billion class settlement. The U.S. Supreme Court has agreed to hear a related case this term. Bayer maintains glyphosate is safe.

Oreskes, author of “Merchants of Doubt,” joined Robyn Vincent on The Metro to discuss how one ghostwritten paper shaped pesticide policy for a generation, and what it means now that it’s been thrown out.

Hear the full conversation using the media player above.

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