Sep 20 2012
By all accounts this study looks like the perfect storm of ideologically motivated pseudoscience. French researchers Gilles-Eric Séralini at the University of Caen, who have a history of opposition to GM food, have published a highly dubious study allegedly linking consuming the GM corn or exposure to the roundup pesticide with increased risk of tumors and death. However:
In an unusual move, the research group did not allow reporters to seek outside comment on their paper before its publication in the peer-reviewed journal Food and Chemical Toxicology and presentation at a news conference in London.
So – they presented their controversial findings, which they consider “alarming,” but prohibited journalists from doing their job before presenting the results. That’s more than suspicious – I think it’s unethical. Transparency in science is critical, especially when that research has immediate implications for public safety and can have a profound effect on public opinion.
It is much easier to provoke fear than to reassure with careful analysis. It’s almost as if the researchers wanted an undiluted initial shock reaction to their research before the careful analysis could even take place.
But the internet moves fast these days, and that careful analysis is already beginning – leaving those news outlets who swallowed the press release in the dust. The New Scientist has an excellent analysis, based partly on a French blogger who has dissected the study. Problems already identified with the study include the following:
- The population of rats used have a high propensity for tumors.
- There were only 20 rats in the control group, and 80 in the exposure groups, an atypical asymmetry.
- The data reports that “some” of the test groups had a higher tumor incidence, while others did not – sounds suspiciously like cherry picking the data.
- The statistical analysis done by the team was atypical, characterized by nutrition researcher Tom Sanders as “a statistical fishing trip,” while a more standard analysis was excluded.
- Exposure to GM corn or the herbicide Roundup had the same negative effects. It is inherently implausible (admittedly not impossible) for such distinct mechanisms to have the same effect.
- There was no dose response at all – which is a critical component of demonstrating a toxic effect.
- The researchers did not control for total amount of food consumed, or fungal contaminants, both of which increase tumors in this population of rat.
These are only the most obvious problems with the study – the kinds of things that journalists would have been told if they were allowed to show the study to other scientists before reporting on the study.
Frankly, if a journalist is given such a restriction I think they should either refuse to report on the study, or solely report about the odd restriction, or ignore the restriction and show it to other scientists anyway. The integrity of the science reporting process is more important than this one study or this one research group.
This group has a clear conflict of interest in that they have a history of strong opposition to GM foods and have published dubious research in the past overcalling the risks of GM food. However, I do not believe that an apparent conflict of interest automatically condemns research, if the research is rigorous and transparent.
However, when you combine a conflict of interest (in this case a strong ideological bias) with questionable research methods and then squirrely dealings with the media, you have cause for concern.
Already the French government has ordered a probe into the possible safety concerns of GM corn. That seems like an overreaction to this one questionable study, but as long as they do an honest inquiry into the science the end result should be legitimate. I just hope they publicize the outcome of their investigation, even if negative, as much as the “alarming” research that provoked it.
51 Responses to “The GM Corn Rat Study”
Leave a Reply
You must be logged in to post a comment.