GM Foods Give Rats Cancer, Except They Don't: A Case Study on Bad Science and Worse PR

An increasingly discredited study led by French researcher Gilles-Eric Séralini purporting to show an increased risk of cancer in lab rats fed genetically-modified maize raised a particularly ugly flag even before it came out. Said flag had to do with...

Oct 13 2012, 1:00pm

The study was a red flag even before it was released to the public. The problem was the embargo: journalists granted early access to the paper (not me!) weren’t allowed to consult any other scientists about said paper before the embargo release date. Meaning, if you wanted to write a story about the results, you couldn’t get a second-opinion. Breaking the embargo supposedly would put the offending journalist on the hook for the entire cost of the study. A journalist could of course just wait until the public release to write something solid with outside sources, but this was too big to wait: a GMO-cancer link, right in the midst of California’s heated GMO labeling debate.

In my years of receiving daily swarms of embargoed research news, I’ve never seen anything like it. But more than just being unusual, it’s really, really gross. That embargo policy has since been disowned by most everyone involved, except Séralini himself.

Embargo Watch, an excellent blog keeping tabs on the somewhat bizarre world of science research embargoes, agrees:

Sorry, folks, but this is an outrageous abuse of the embargo system — which, after all, is an agreement between two parties. One of the main reasons for embargoes — if you take many journals at their word — is to give reporters more time to write better stories. Part of how you do that is talking to outside experts. And scientists — ones interested in science, anyway, not those interested in spin and political points — should welcome that kind of scrutiny.

The embargo was message control, of course. The study, now available at the (obviously not biased in any direction [not that sustainable food is a particularly bad bias to have]) Sustainable Food Trust website, has a similarly unusual PR machine behind it. There’s a related book and a movie out even. Head over to the SFT site right now and tell me something doesn’t feel a little, well, conflicty. Meaning, there’s an ugly sense of ownership over the study by an organization that is clearly more interested in a particular result: GM foods produced negative health effects.

The study has been latched onto by the whole anti-GMO crew at large, as one might expect. But the really ugly thing is that, sans PR offensive screaming otherwise, the study doesn’t prove anything. At all. It demonstrates some not-pretty things about its proponents, but not so much about GMOs and cancer. This has been widely discussed elsewhere — The New York Times has a good breakdown — and last week, the European Food Safety Authority and Germany's Federal Institute for Risk Assessment both slammed the results.

In a press release, the EFSA, said: "The design, reporting and analysis of the study, as outlined in the paper, are inadequate," and that the paper is insufficient to be used as a basis for risk assessment. The basic idea behind the complaints is that the study used a too-small sample of a particular breed of rat prone to developing cancer anyway. While the study (or its mouthpiece rather) boasts about looking at rats over their entire average lifespan, only about one-third of the variety of rat used for the study lives to 104 weeks, which for such a small sample size (10 rats of each sex), is not a high enough survival rate. You’d need about 64 rats to find statistical significance.

The GMO-fed rats probably would have gotten cancer anyway, is the point. And, of course, one bullshit study doesn’t prove that GM food is safe either. Meanwhile, Séralini refuses to release his data, on the (not at all becoming for a scientist) grounds that Monsanto won’t release its data either. He seems fairly demure in comments to Nature (which, in another red flag, wasn’t on the list of journalistic outlets to receive an advance copy of the paper):

"Of course, this should be replicated by others, but we believe in these results," he says. He agrees that more rats would have boosted his study's statistical power, but says that he did not design the experiment to show differences in tumour incidences, because he was not expecting to find any — no previous tests on GM foods had suggested a cancer risk.

It seems they still don’t.

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