Smell a rat? Flawed GM cancer study highlights flawed media approach


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Five of the ten controls developed tumours too
Five of the ten controls developed tumours too

Related tags Gm crops Genetically modified food Genetically modified organism Gm

A French study on the effects of Monsanto’s genetically modified (GM) maize in rats has said little about the safety or otherwise of GM crops – but it has said plenty about how the media can be used to push an agenda.

The study itself has been widely criticised, but at a time when pressure is on reporters more than ever to be the first news organisation to ‘break’ a story, many members of the public will have read nothing but the initial, scaremongering reports – which reflect exactly what the researchers intended.

There are several issues that bother me here. However, as a journalist, top of the list is the fact that reporters given pre-embargo access had to sign an agreement that they would not speak to any outside experts before the embargo was lifted.

This more or less guaranteed that no early reports would question Séralini’s findings – and, worryingly, some pretty well-respected news outlets agreed to this condition. The contract was essentially an abuse of the media, and of the embargo system, to quash early criticism.

It also took advantage of journalists who failed to grasp that the peer review process is not gospel; even published studies need to be questioned.

Nearly immediately, anti-GM groups started leveraging the reports to push their agenda​, leading Russian authorities to temporarily ban imports of the crop and the French government to call for an EU-wide ban.

Passion and urgency, but a lack of data

There are few issues in food today that stir up such impassioned – and such ill-informed – views as GM materials in our food supply. As such, Séralini et al knew that many news outlets would take their results as presented, run with them, and never take a second look, and in many cases they were right.

Meanwhile, the researchers have refused to publish their full data set.

Frankly, this is bizarre. It is normal and expected for scientists to make their data available so others can assess their methodologies and attempt to replicate results.

However, even without the full data, there were some glaring faults, as EFSA and other food safety agencies around the world​ have pointed out.

I smell a rat…

Some of the most obvious were the small sample size (just ten per group) and that the rats used were genetically predisposed to develop tumours. In fact, the Sprague-Dawley rats have a 70 to 95.8% chance​ of developing tumours within their two-year lifespan – that’s before any treatment of any kind. Especially if they only number ten, these rats were not suitable controls, and it’s hardly surprising that five of the ten Sprague-Dawley rats in the control group developed tumours.

In addition, Séralini listed no conflict of interest for this study, but Embargo Watch – which has an interesting take on this issue​ – pointed out that he also has a book on GMOs out this week. Coincidence…?

In short, it doesn’t matter what your ideologies are, this study was hugely flawed. Nevertheless, it managed to get a lot of publicity with little analysis by taking advantage of the media’s desire to be first on a story in a high-speed world.

It actively took advantage of widespread paranoia about GM foods and a lack of understanding of scientific methodologies.

So what next?

We need a cool head to examine what is going on with the safety or otherwise of GM crops, without the baggage of a predetermined viewpoint. Unfortunately, few individuals have that, even researchers, as this study underlines.

My hope is that there are lessons to be drawn anyway; it could lead to better testing of the safety of GM crops, including the development of methodologies that will be acceptable to global food safety authorities…as well as a much larger dose of scepticism among journalists next time someone tells them to whom they can and cannot talk.

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1 comment

Serafini's conclusions

Posted by David Whitley,

Thank you for discussing this important study. I thought the main conclusion of Serafini was that more and bigger studies needed to be done and that the design and results of his study were adequate to justify that conclusion. I got the impression that most of the criticisms surrounding the study have been on the conclusions of the press rather than those of the researchers.
It could be that the researchers took advantage of the febrile mental landscape within the media however it seems strange to blame them for it. Better do something that will contribute to greater balance of individual and collective mind in future. (I have suggestions to offer if you are interested).
I have no expertise in experimental design but it has been pointed out that treatment groups of 10 rats is the norm in the 90 day feeding studies that have previously been accepted as demonstrating the safety of GM foods. Given the small numbers in seems sensible to choose a strain of rats that is susceptible to cancer and see whether there is a significant difference between the treatment groups. If they are not susceptible you may get no cancers in either group and learn nothing and if they are too susceptible you may get too many cancers in both groups and learn nothing. In this case the susceptibility seems to have fitted the group size and treatment.
I do not see the validity of saying that the researchers had a predetermined viewpoint. They may have had expectations but they set up and carried out a two-year randomised trial to reduce the influence of those expectations. Perhaps those who conduct 90-day trials have been less driven by an inquiring mind than Serafini.
Please do keep this matter under scrutiny at least until more bigger and better studies are conducted and the truth becomes clearer.

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