WHO cancer agency edited “non-carcinogenic” findings from its glyphosate report

LONDON (Reuters) — The World Health Organization’s cancer agency dismissed and edited findings from a draft of its review of the weedkiller glyphosate that were at odds with its final conclusion that the chemical probably causes cancer.

Documents seen by Reuters show how a draft of a key section of the International Agency for Research on Cancer’s (IARC) assessment of glyphosate — a report that has prompted international disputes and multi-million-dollar lawsuits underwent significant changes and deletions before the report was finalized and made public.

IARC, based in Lyon, France, wields huge influence as a semi-autonomous unit of the WHO, the United Nations health agency. It issued a report on its assessment of glyphosate —a key ingredient in Monsanto Corp’s top-selling weedkiller RoundUp — in March 2015.

It ranked glyphosate a Group 2a carcinogen, a substance that probably causes cancer in people.

That conclusion was based on its experts’ view that there was “sufficient evidence” glyphosate causes cancer in animals and “limited evidence” it can do so in humans.

The Group 2a classification has prompted mass litigation in the United States against Monsanto and could lead to a ban on glyphosate sales across the European Union from the start of next year.

The edits identified by Reuters occurred in the chapter of IARC’s review focusing on animal studies.

This chapter was important in IARC’s assessment of glyphosate, since it was in animal studies that IARC decided there was “sufficient” evidence of carcinogenicity.

One effect of the changes to the draft, reviewed by Reuters in a comparison with the published report, was the removal of multiple scientists’ conclusions that their studies had found no link between glyphosate and cancer in laboratory animals.

In one instance, a fresh statistical analysis was inserted – effectively reversing the original finding of a study being reviewed by IARC.

In another, a sentence in the draft referenced a pathology report ordered by experts at the U.S. Environmental Protection Agency. It noted the report “firmly” and “unanimously” agreed that the “compound” — glyphosate — had not caused abnormal growths in the mice being studied. In the final published IARC monograph, this sentence had been deleted.

Reuters found 10 significant changes that were made between the draft chapter on animal studies and the published version of IARC’s glyphosate assessment.

In each case, a negative conclusion about glyphosate leading to tumors was either deleted or replaced with a neutral or positive one. Reuters was unable to determine who made the changes.

IARC did not respond to questions about the alterations. It said the draft was “confidential” and “deliberative in nature.”

After Reuters asked about the changes, the agency posted a statement on its website advising the scientists who participate in its working groups “not to feel pressured to discuss their deliberations” outside the confines of IARC.

Reuters contacted 16 scientists who served in the IARC expert working group that conducted the weedkiller review to ask them about the edits and deletions.

Most did not respond; five said they could not answer questions about the draft; none was willing or able to say who made the changes, or why or when they were made.

The chair of the IARC sub-group tasked with reviewing evidence of glyphosate’s effect on laboratory animals was Charles Jameson, an American toxicologist.

In testimony as part of personal-injury lawsuits against Monsanto in the United States, Jameson told lawyers for Monsanto he did not know when, why or by whom the edits had been made.

Monsanto is facing multiple legal claims in the U.S. from plaintiffs who allege glyphosate gave them or their loved ones cancer. Jameson is an expert witness for the plaintiffs.

He did not respond to questions for this article.

Scott Partridge, Monsanto’s vice president of global strategy, told Reuters the changes to the draft showed how “IARC members manipulated and distorted scientific data” in their glyphosate assessment.

IARC declined to comment.

Numerous national and international agencies have reviewed glyphosate. IARC is the only one to have declared the substance a probable carcinogen. Compared with other agencies, IARC has divulged little about its review process.

Until now, it has been nearly impossible to see details, such as draft documents, of how IARC arrived at its decision.

The European Food Safety Authority (EFSA) said that in its assessment of the weedkiller, the scientific decision-making process “can be traced from start to finish.” Jose Tarazona, head of EFSA’s pesticides unit, told Reuters: “Anyone can go to EFSA’s website and review how the assessment evolved over time. So you can see clearly how experts … appraised each and every study and also how comments from the public consultation were incorporated into the scientific thinking.”

In the United States, the Environmental Protection Agency published a full 1,261-page transcript of a three-day scientific advisory panel meeting on its ongoing evaluation of the carcinogenic potential of glyphosate in December 2016.

No such record of the deliberations behind IARC’s monographs is published.

In a previous response to questions about the transparency of the IARC process, the agency’s director, Chris Wild, referred Reuters to a letter in which he said his agency’s assessments are “widely respected for their scientific rigor, standardized and transparent process.” Wild also said IARC’s methods are intended to allow scientists to engage in free scientific debate at its monograph meetings.

IARC says its working group scientists are selected for “their expertise and the absence of real or apparent conflicts of interest.”

For the panel that evaluated glyphosate and four other pesticides in what is known as IARC’s Monograph 112, scientists from 11 countries met at the agency’s headquarters in Lyon for a week-long meeting starting on March 3, 2015.

The meeting “followed nearly a year of review and preparation” by IARC staff and working group members, “including a comprehensive review of the latest available scientific evidence,” IARC said in a statement at the time.

In June, Reuters reported how the chair of the IARC working group was aware of new data showing no link between glyphosate and cancer in humans, but the agency did not take it into account because it had not been published.

No drafts of IARC’s glyphosate assessment have surfaced before. However, a draft was obtained by Monsanto as part of the legal proceedings in the United States. Reuters reviewed chapter 3, the section on animal studies, which is the only section no longer covered by a confidentiality order of the court.

The glyphosate review in IARC’s Monograph 112 runs to 92 pages; the chapter on animal studies consists of just over 10 pages. Reuters has not seen any other sections of the draft and cannot say whether they also underwent significant edits.

In comparing draft and final versions of chapter 3, Reuters found that in several instances comments in the draft were removed; the comments noted that studies had concluded glyphosate was not carcinogenic. They were replaced in the final version with the sentence: “The Working Group was not able to evaluate this study because of the limited experimental data provided in the review article and supplemental information.”

This sentence was inserted six times into the final version.

Each time it replaced a contrary conclusion, noted in the draft, by the original investigators on the study being considered, such as: “The authors concluded that glyphosate was not carcinogenic in Sprague Dawley rats”; “The authors concluded that glyphosate technical acid was not carcinogenic in Wistar rats”; and “The authors concluded that glyphosate was not carcinogenic in CD-1 mice in this study.”

Reuters also found changes to the conclusions and statistical significance of two mouse studies. These studies were cited in IARC’s ultimate finding of “sufficient” evidence that glyphosate causes cancer in animals.

One edit concerned a 1983 study in mice. IARC’s published monograph contains a fresh statistical analysis calculation as part of its review of that study. The original investigators found no statistically significant link between glyphosate and cancer in the mice. IARC’s new calculation reached the opposite conclusion, attributing statistical significance to it.

This new calculation was inserted into the final published assessment, but was not in the draft version seen by Reuters. The change gave the working group more evidence on which to base its conclusion that glyphosate was probably carcinogenic.

In further discussion of the same 1983 study, IARC’s final published report refers to expert pathologists on a panel commissioned to reanalyze the work of the original investigators. The IARC draft notes that these pathologists “unanimously” agreed with the original investigators that glyphosate was not related to potentially precancerous tissue growths in the mice. IARC’s final report deletes that sentence.

Reviewing a second mouse study, the IARC draft included a comment saying the incidence of a type of animal cancer known as haemangiosarcoma was “not significant” in both males and females. IARC’s published monograph, by contrast, inserts a fresh statistical analysis calculation on the data in male mice, and concludes that the findings were statistically significant.

IARC’s assessment that gly-phosate is a probable human carcinogen is an outlier. In the 40 or so years since the weedkiller first came to the market, glyphosate has been repeatedly scrutinized and judged safe to use.

A year after IARC issued its evaluation, a joint United Nations and World Health Organization panel reviewed the potential for glyphosate in food to cause cancer in people. It concluded the weedkiller was “unlikely to pose a carcinogenic risk to humans.”

The U.S. Environmental Protection Agency, which first assessed glyphosate in the 1980s and has reviewed it several times since, says it has “low toxicity for humans.”

The European Food Safety Authority and the European Chemicals Agency, which advise the 28 members of the EU, have also assessed glyphosate within the past two years and ruled it safe.

But IARC’s Monograph 112 has had great influence.

It is weighing heavily on a pending European Union decision – due by the end of the year and possibly to be made next week – on whether glyphosate should be relicensed for sale across the 28 member states. France, one of the bloc’s agricultural powerhouses, has said it wants the weedkiller phased out and then banned, provoking protests by its vocal farmers, who argue glyphosate is vital to their business.

A failure to renew glyphosate’s license by the end of the year would see an EU ban kick in on Jan. 1, 2018.

In the United States, Monsanto – the firm that first developed and marketed glyphosate – is facing litigation in California involving at least 184 individual plaintiffs who cite the IARC assessment and claim exposure to RoundUp gave them a form of cancer known as non-Hodgkin lymphoma. They allege Monsanto failed to warn consumers of the risks. Monsanto denies the allegations. The case is ongoing.

Members of the U.S. Congress, concerned about what they described as IARC’s “inconsistent” standards and determinations for classifying substances as carcinogenic, last year launched investigations into American taxpayer funding of IARC. The investigations are ongoing.

In Europe, IARC has become embroiled in a public spat with experts at the European Food Safety Authority, which conducted its own review of glyphosate in November 2015 and found it “unlikely to pose a carcinogenic hazard to humans.”

With IARC monograph meetings, some outside observers are selected and allowed to witness proceedings, but they are banned from talking about what goes on. Journalists are generally not allowed in.

Last year, Reuters reported on an email sent by IARC to the experts on its glyphosate working group in which the agency advised them not to discuss their work or disclose documents. The email said IARC “does not encourage participants to retain working drafts or documents after the monograph has been published.”

Reuters sent questions about the draft version of the glyphosate assessment to members of the IARC working group that assessed the herbicide as well as to the head of IARC’s monograph program, Kurt Straif, and to Kathryn (Kate) Guyton, the staffer responsible for the glyphosate review. IARC responded by posting the following message on its website:

“Members of the IARC Monograph Working Group which evaluated glyphosate in March 2015 have expressed concern after being approached by various parties asking them to justify scientific positions in draft documents produced during the Monographs process. IARC would like to reiterate that draft versions of the Monographs are deliberative in nature and confidential. Scientists should not feel pressured to discuss their deliberations outside this particular forum.”

IARC answered none of Reuters’ specific questions about changes to the draft.



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  • RobertWager

    Add to this the $160,000 Portier has received from class action lawyers suing Monsanto claiming glyphosate caused cancer.

    Add to that someone at IARC witholding tow key reports that both found glyphosate did not cause cancer.

    • Harold

      Is WHO offering just their own statements, or are they offering sworn documents under oath. Is the WHO offering signed documents or just Banner and Title say so? There is a big difference between statements or opinions vs sworn statements and affidavits. The WHO is not a court of Law; perhaps you think that they are. Do you believe that the WHO organization is capable of overseeing itself? The fact that there is opposition is a fact that all the facts have not been placed upon the table. Do you care to justify and legitimize their secrecy for me; it seems to be everyone’s specialty these days.

    • SUNNY

      It is always interesting to watch how your industry always tries to smear the scientists whose data and science conflict with the industry junk pseudo-science ideology.

      The IARC only uses peer reviewed studies. There are many industry sympathizers who would like them to lower their scientific standards and look at non-published non-peer reviewed studies. Many of these studies are of lesser quality and many have been manipulated by industry to support their junk pseudo-science agenda. The IARC did the right thing by upholding their strict quality requirements for the studies they consider.

      Why would you want to see junk science used to make decisions instead of upholding the quality requirements of the IARC, which is the foremost cancer research agency on the planet?

    • ed

      Monsanto’s own scientists found that their agent orange derivative caused cancer. A little extra cash gets rid of most of that type of thing but still it is a bit unethical don’t you think.

    • Kissing optional
  • RobertWager

    It explains a great deal about how this one organization found the exact opposite to every other review in the world.

    • ed

      The pressure from Monsanto was to dumb it down from “it does cause cancer”, a finding that they themselves long knew about their agent orange derivative from their own internal scientific research, to “it may cause cancer”. That was not good enough to fend off the lawsuit in North America, so now we must go one step farther to, “it is so safe that you can srink it.” That is something that when asked have refused to do to date. In fact one of them said when asked to drink it, ” you would have to be a retard to drink yhat stuff. They are ever more afraid of it than they are of the cancer.

    • SUNNY

      Every other review in the world? I think you made that up.

    • Shlomo
  • Kissing optional

    Removing the declaration that all of Monsanto’s ‘scientists’ claimed they didn’t find a link in animals …
    did anyone doubt that this was their claim in the first place?
    And does their claim of denial really have anything to do as relevant to the published declaration of what the non-Monsanto scientists observed?

  • Corolla Sedan

    Cancer is fungus should we blame every fungal food manufacturer,dairy farmers who feed their cattle with silage,poultry farmers who feed their poultry with medicated pellets,meat growers who give antibiotic to animals,builders who build suspended floor houses for fungus to grow underneath,sugar cane growers as sugar feeds candida which creates all these fancy diagnostic names diseases.Finally fungus is in the air around the globe,whom should we sue for that GOD?Yes phosphates do contribute to cancer,but who on earth is sure enough to point finger at Monsanto only.First we should point finger at Chem trails,this should be good starting point.

    • Happy Farmer

      Thanks for the good laugh.

      • ed


      • Corolla Sedan

        The reason you are happy laughing is, there is one synthetic hormone called Oxytocin sprayed Globally also when you see pinkish clouds that’s Lithium to sedate you.

    • Harold

      You have listed problems and for each of them we already have in place governing authority’s who are mandated to solve those problems but they continue to fail. For each problem there has already been a “starting point’ and each of those who were in charge of it; but what hinders the public? It certainly isn’t God. You can always do what you think seems fit in the pursuit of money, but if you die in the process, by disrupting your own god given nature, God wins either way. Behind every problem there are those with tremendous wealth. How has making the ultra rich – just that – rich – been good for us? We have allowed them to control every aspect of our lives and now we are witnessing what they have left behind for us to control; only our measures of servitude.
      Unlike Happy Farmer, I did not see a “good laugh.” Your points were well taken.

    • GreenSenior

      Chem trails? Really? Give it up….it’s a pipe dream.

      • Harold

        Tell me all about Chem trails. I’d like to know what you think Corolla needs to give up on. Tell me of names of the three chemicals that the aircraft are spraying into the atmosphere on a regular basis. Tell me about cloud seeding while your at it. Id like to know what the “dream” is and what you were referring to exactly.

      • Corolla Sedan

        May chem trails have mercy upon your innocent mind.Google Australia to be vaccinated for cholera by Paxvax aerosol company.Do not put your head out from under rock you live, they will spray you for cholera so they say.It could be another Tuskegee experiment.

  • Denise
  • dave bainard

    IARC ‘scientist’ get lessons from IPCC ‘scientist’ on how to retain their paychecks through circle jerk consensus.

    • GreenSenior

      Way to go, Dave! And the world is flat and the sun revolves around the Earth. Yay, the truth at last!

      • Harold

        Do you find pleasure in your agreement with the masses? At one time the masses did believe the earth was flat and also people were jailed as heretics by the church and state for not believing that the sun evolves around the earth. As it was then and as it is today, the very few were the ones who knew of, or did discover the truth; discoveries were not ever accredited to the masses and their collaborative mainline opinions. You seem to be of the opinion that if the masses say so – then what you are hearing must be true; that is the “consensus” – right?

  • Denise

    Facts vs fiction. Most people want to know the truth (facts) and have a right to know so they can protect their families from harmful chemicals and products. This is the service US Right To Know (usrtk) provides for people.

    • Happy Farmer

      Yes, people do deserve the truth. This article shows there are people stretching and manipulating the (truth, facts, fictions, etc), on every front.
      Including the sources you and I like to cite.

      • Kissing optional

        Actually sir, you do not include sources.
        You protect your choice by mockery.
        As in your reply to Corolla
        ‘Happy Farmer’
        “Thanks for the good laugh.”

  • Tom Phischer

    Wow talk about fake news , actually accusing the WHO of deception! These are the world’s top independant scientists… billions at stake so no wonder the pressure to report this bs

  • Shlomo

    the above article is shown to be deception:


  • FarmersSon63

    This will be the end of the IARC.

  • bufford54

    Pass the salt…….

  • GreenSenior

    According to “Nation of Change” & “The Guardian,” the European Food Safety Agency “cut and pasted” large sections of Monsanto research INTO the findings IT used to conclude that glyphosate is probably NOT carcinogenic. https://www.nationofchange.org/2017/09/16/european-glyphosate-safety-report-copy-pasted-monsanto-study/
    Might it be that THOSE are the sections IARC DELETED from its own research (& referred to in this story) concluding the opposite? This is such a convoluted story by now (as are most involving Monsanto), it’s hard to know, exactly. But if that IS the case, I believe IARC did the right thing!

  • Happy Farmer

    You are right-I do not have sources listed. So, what if I said “It appears that almost all sources are subject to stretching and manipulating data, regardless of which side they are on”.

    My reply to Corolla was not intended to be mockery at all. My thoughts when reading it were that he was mocking all “those facts”. That is why it is a good laugh for me. If that is not what he intended to do, I still did not intend to mock him. You only assumed that.

    • Kissing optional

      Very well sir. I accept that you assumed and I assumed.
      Now I look forward to any peer reviewed, independent links you would care to post within the bounds of WP’s criteria in regards to what is a safe dosage for human consumption of the patent guaranteed mineral chelator, glyphosate.
      By human consumption, I am referring to drift and or residual at any point of the usual three to five applications typical of ‘conventional’ agribiz operation, be it pre, post, late immergent, desiccate and any or every other application.

      • Happy Farmer

        Here’s a fact from my farm regarding glyphosate use. I spray glyphosate as a pre-burn 1 time per season. On about 1/3 of my fields I spray it Post-harvest to control perennial weeds.

        • Kissing optional

          I am always curious if a farmer would even consider using the chemical if it wasn’t a subsidized by tax payer thru the ‘inputs deduction’?
          I understand the reluctance to recognize the harm because of the profit, but if the farmer had to actually pay the full cost, would the blinders remain?
          Please understand, I know you didn’t implement the tax structure and you certainly didn’t create the propaganda that it is a benign product.
          But when they say “you can drink it”… please, don’t.

  • Denise

    Reuter’s reputation for fair and balanced reporting isn’t what it used to be. Somebody got to them.

  • RobertWager

    Did you actually read this article that outlined exactly what IARC did? I think not.

  • Bern Sand

    During a chat with a contractor in Northern BC, hired by a
    Timberlands (TFL) licensee to mark-off and area of which SOON to be sprayed, I
    shared my concerns about these sprays used in recently logged off area; the
    comment back was this (glyphosate) herbicide spray is harmless…”you
    could drink the stuff” WHY DOES this SPRAY KILL EVERTHING..except
    the spruce then. NO ANSWER. “I want to see you drink a cup
    of this stuff” You don’t need scientific documentation to tell you
    that this glyphosate (SPRAYS) KILLS healthy foliage…

  • Harold

    Question: If “these are the world’s top independent scientists” (WHO); why suddenly did they change their minds about glyphosate? Monsanto = good scientist. No Monsanto = good scientist. Monsanto examiner = bad scientist.


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