The Ghostwritten Glyphosate Study That Misled Regulators for 25 Years

For 25 years, one paper shaped global opinion about glyphosate's safety.

Regulators cited it. Policymakers leaned on it. Industry waved it like a permission slip.

And here in New Zealand, the same paper helped justify why glyphosate-based weedkillers such as Roundup® were treated as "low risk" and allowed to saturate our food, soil, and waterways with almost no independent oversight.

But now something extraordinary has happened:

That cornerstone paper has finally been retracted.

And not because of new science.

Because of ghostwriting.

The Cornerstone Glyphosate "Safety" Study Has Been Retracted

That's right.

The now-retracted paper — Williams, Kroes & Munro (2000) — concluded confidently that "under present and expected conditions of use, Roundup herbicide does not pose a health risk to humans".

The retraction notice says: "The paper had a significant impact on regulatory decision-making regarding glyphosate and Roundup for decades."

However, US Roundup/cancer litigation in 2017 revealed it to have been ghostwritten by Monsanto.

Yet in spite of that revelation, it continued over two decades to be cited as evidence supporting glyphosate's safety. This fact was subjected to strong criticism in a peer-reviewed paper.

Let that land for a moment.

A ghostwritten paper — presented as independent science — shaped global policy for 25 years.

Why Was This Paper So Influential?

The paper, by Williams, Kroes, and Munro, was published in 2000 and concludes, "under present and expected conditions of use, Roundup herbicide does not pose a health risk to humans".

For decades, it was treated as the foundational safety review behind regulator decisions.

Was It Really Ghostwritten by Monsanto?

But during US Roundup cancer lawsuits in 2017, court documents revealed something shocking:

Monsanto ghostwrote the paper.

Not "industry contributed." Not "industry provided data." Ghostwrote.

Regulators Kept Using It Anyway

Even after the ghostwriting became public, the Williams/Kroes/Munro paper continued to be cited by agencies, consultants, and industry groups defending glyphosate's safety.

In fact, a later peer-reviewed critique warned that relying on such tainted evidence undermines public trust and distorts chemical regulation.

Yet nothing happened.

Not until now.

What This Means for New Zealand

This retraction:

• Undermines the scientific foundation regulators used to claim glyphosate is "non-carcinogenic"
• Calls into question historical approvals and reassessments
• Strengthens the case for a full, independent, transparent review of glyphosate-based weedkillers
• Highlights the risk of relying on industry-funded data over independent evidence

And frankly, it raises the obvious question:

If the cornerstone paper is now gone, what exactly is left holding up the claim that glyphosate is safe?

A Major Shift in the Glyphosate Evidence Base

And meanwhile, our own testing at NoMoreGlyphosate.nz has found glyphosate or AMPA in common household foods — including honey, Weet-Bix, and cereals.

How can New Zealand continue to rely on regulatory decisions built on a foundation we now know was compromised?

Where This Leaves Us

This isn't a footnote.
This isn't an academic technicality.

This is a pillar collapsing.

A key paper is gone.
A quarter‑century of regulatory reassurance suddenly looks fragile.
And the burden shifts — finally — back onto regulators to prove glyphosate's safety with real, independent, transparent evidence.

Because one thing is clear:
If a ghostwritten paper can shape regulation for 25 years, then something in the system is deeply broken.

New Zealand has a chance to do better.
The question now is: will we?