Monsanto is stepping up its attack on the WHO's classification of glyphosate as a probable human carcinogen, writes Peter Saunders. Dismissing the finding as 'junk science' the company is convening its own industry friendly panel and pushing its secret studies at regulators. Don't let them get away with it!

In May 2015, the leading medical journal Lancet Oncology published a brief account of a review by the International Agency for Research on Cancer (IARC) [1].

The IARC working party had considered five organophosphate pesticides, tetrachlorvinphos, parathion, malathion, diazinon and glyphosate, and had classified the first two as possibly carcinogenic and the other three as probably carcinogenic.

Four of the evaluations appear to have been accepted with little or no comment. Glyphosate, however, is central to a highly profitable and powerful industry, the manufacture of glyphosate-based herbicides and the development and supply of glyphosate-tolerant GM crops to be used with them.

So Monsanto, the leading company in the field, instead of engaging the IARC working group in a discussion of its results and their implications, immediately dismissed the review as "junk science" and demanded its immediate retraction.

The IARC Monograph is based entirely on published science

Contrary to the impression you might get from Monsanto's press releases, this was not a study specially set up to attack glyphosate. The IARC was created by the WHO in 1965 to promote international collaboration in cancer research. It was soon being asked for advice on whether certain agents (mostly chemicals) in the environment and in food were carcinogens.

Because gathering together and evaluating the relevant information turned out to be a major task, the IARC began commissioning panels of experts to review the evidence on particular agents or groups of similar agents. The latest volume of monographs, on five organophosphate pesticides, is the 112th in the sequence.

The panels do not decide for themselves how to proceed. They follow guidelines that were set up in 1971 and have since been modified from time to time in the light of experience. These are described in the Preamble to the IARC Monographs, which is available on the web [2].

A key feature of the IARC process is transparency. The members of the working group must have no real or perceived conflicts of interest. The evidence they consider must be openly available.

This is in complete contrast to reviews carried out by the industry or by regulators, which are largely based on evidence that independent scientists are not allowed to see. Remember that Gilles-Eric Séralini had to resort to a Freedom of Information suit to discover the evidence on the basis of which the EU had licenced Monsanto's GM maize MON810.

The working group must explain in detail in their report how they arrived at their evaluations. There is a strict protocol for deciding in which category a substance is to be placed, from Group 1, 'The agent is carcinogenic to humans' to Group 4, 'The agent is probably not carcinogenic to humans'.

In this case, the Working Group explain that they have placed glyphosate in Group 2A, 'probably carcinogenic to humans', because they found sufficient evidence to establish that glyphosate is carcinogenic in animals, but that while there is a clear association between glyphosate and cancer in humans, they cannot completely rule out the possibility that this is due to chance, bias or confounding, rather than cause and effect.

They also considered that the data on genotoxicity (damage to the genetic information in cells) and oxidative stress (disturbance to the balance of free radicals) provide independent support for the classification [1].

The IARC stopped just short of saying that glyphosate definitely causes cancer, but on this evidence I wouldn't bet against it. Which is what the industry is telling us to do.

Monsanto's response - obscure and belittle

Monsanto reacted exactly as we have come to expect: they immediately demanded that the WHO retract the monograph. They tried to play down the importance of the classification by pointing out that Group 2A also includes working in barber shops and shift work.

They did not, however, explain on what grounds they were rejecting the evidence in earlier IARC monographs that both do in fact increase the risk of cancer [3,4]. They criticized the IARC for taking only a week to carry out its evaluations [5,6], when the meeting they were referring to was only the final stage in a process that had taken a year.

Monsanto's chief argument is that many regulatory agencies have found glyphosate is safe. That would carry more weight if the regulators had carried out their own research and if the results of all the experiments were available for independent scientists to study. But that isn't what happened. It is generally a matter of the agency accepting the word of the industry, and on the basis of evidence that no one else is allowed to see.

Recently, for example, it was announced that an EU study had concluded glyphosate is safe and that therefore its license to be used in Europe should be renewed [7]. The announcement explained that the review had been carried out not by an EU agency but had been delegated to one country, Germany, as "Rapporteur Member State."

What the announcement did not explain was that rather than doing the work itself, the German Federal Institute for Risk Assessment (BfR) had delegated it to a body called the Glyphosate Task Force, a consortium of chemical and biotech companies including Monsanto "joining resources and efforts in order to renew the European glyphosate registration with a joint submission." [8], [9]. It is difficult to conceive of a more blatant conflict of interest.

The BfR's reaction to the IARC report is interesting. They write [6],
"It is not possible to fully comprehend the indications for a genotoxic potential of glyphosate based on the short report published by IARC, in particular also due to the fact that the assessment included studies using different glyphosate containing plant protection products that are not specified in any detail."
This sounds like someone trying to cover their back, just in case handing the review over to the biotech industry turns out not to have been such a good idea after all. The world's regulators must be all too well aware that if the IARC conclusions are accepted, they are going to have to explain to their governments why they gave them such egregiously bad advice.

Governments may have put pressure on the regulators to accept what the industry told them, but if things go wrong it is the regulators that will be hung out to dry.

The BfR does, however, raise an important point. Almost all the relevant studies have been on glyphosate alone. But no one uses pure glyphosate as a herbicide. It is always combined with adjuvants, chemicals that are added to make it more effective.

Thus what is being tested is not what we are actually being exposed to. The industry and the regulators insist that this does not matter because the adjuvants are inert. Only they are not inert. Just to cite one example, research has shown that the polyethoxylated tallowamine POE-15, a major adjuvant in Roundup, is highly toxic [10].

In any case, the whole point of adjuvants is that the mixture is a much more effective herbicide than the so-called active ingredient (in this case glyphosate) used alone. So we would expect the mixture to be more toxic and more carcinogenic too. It is possible that it might not be, but it is foolhardy to licence the herbicide without bothering to find out.

Monsanto's next steps ... setting up its own 'panel'

Having failed to bully the WHO into retracting the monograph, Monsanto have announced that they are asking Intertek Science & Regulatory Consultancy, a commercial firm, to convene and facilitate a panel of its own.

We do not yet know the members of the panel or how it will carry out its work, but Intertek states on its web site [11] that its guiding principle has always been "to protect client interests while helping our clients achieve their milestones in bringing new products to market, or proactively defending established ones." In this case, of course, the client will be Monsanto.

In the meantime, according to the Washington State University web site, a collaboration between a WSU researcher and Monsanto has found no glyphosate in breast milk from women in areas where Roundup is used [12].

This claim is in contradiction to earlier research, and there are several important questions about how it was carried out that cannot be answered because the work has never been published nor the details made available [13]. The US Environmental Protection Agency (EPA) has nevertheless indicated it will include this study in its review of glyphosate regulations. Why?

Unpublished studies must be disallowed in this process

The IARC has found that glyphosate is carcinogenic to animals and probably carcinogenic to humans [14]. The review was carried out by an international panel of experts, none of whom had conflicts of interest, real or perceived.

It must be taken seriously, just as the 111 previous IARC volumes have been. For Monsanto to dismiss it out of hand tells us more about Monsanto than about the monograph.

The GM lobby accuses the IARC of cherry-picking the evidence because it did not take into account all the research that some others have included in their reviews, but the Working Group followed long-established criteria which specify that only evidence that is openly available and whose quality and relevance can therefore be judged by the panel may be considered. Regulators should adopt the same practice.

Decisions about human safety and the environment are far too important to be taken on the basis of evidence that other scientists and the public are not allowed to see.

Action: Add your name to the Independent Scientists Manifesto on Glyphosate.

This article was originally published by the Institute of Science in Society (ISIS).

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  12. "WSY researchers find U.S breast milk is glyphosate free." Will Ferguson, WSU News, 23 July
  13. "WSU researchers fnid glyphosate-free breast milk for Monsanto. Sustainable Pulse, 24 July 2015.
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