GMO: The Seralini Study

Remember a researcher named Gilles-Eric Seralini, his 2012 GMO study, and the controversy that swirled around it?

He fed rats GMOs, in the form of Monsanto’s Roundup Ready corn, and they developed tumors. Some died. The study was published in the journal, Food and Chemical Toxicology (wikipedia). Pictures of the rats were published.

A wave of biotech-industry criticism ensued. Pressure built. “Experts” said the study was grossly unscientific, its methods were unprofessional, and Seralini was biased against GMOs from the get-go. Monsanto didn’t like Seralini at all.

The journal which published the Seralini study caved in and retracted it.

Why? Not because Seralini did anything unethical, not because he plagiarized material, not because he was dishonest in any way, but because:

He used rats which (supposedly) had an inherent tendency to develop tumors (the Sprague-Dawley strain), and because he used too few rats (10). That’s it. Those were Seralini’s errors.

Well, guess what? Eight years prior to Seralini, Monsanto also did a rat-tumor-GMO study and published it in the very same journal. Monsanto’s study showed there were no tumor problems in the rats. But here’s the explosive kicker. Monsanto used the same strain of rats that Seralini did and same number of rats (10). And nobody complained about it.

Michael Hansen, senior scientist at Consumer’s Union, explains in an interview with Steve Curwood at (click here for the full article):

“Well, basically what Dr. Séralini did was he did the same feeding study that Monsanto did and published in the same journal eight years prior, and in that study, they [Monsanto] used the same number of rats, and the same strain of rats, and came to a conclusion there was no [tumor] problem. So all of a sudden, eight years later, when somebody [Seralini] does that same experiment, only runs it for two years rather than just 90 days, and their data suggests there are problems, [then] all of a sudden the number of rats is too small? Well, if it’s too small to show that there’s a [tumor] problem, wouldn’t it be too small to show there’s no problem? They already said there should be a larger study, and it turns out the European Commission is spending 3 million Euros to actually do that Séralini study again, run it for two years, use 50 or more rats and look at the carcinogenicity. So they’re actually going to do the full-blown cancer study, which suggests that Séralini’s work was important, because you wouldn’t follow it up with a 3 million Euro study if it was a completely worthless study.

CURWOOD: Now as I understand it, the Séralini work is one of among only very few studies that have been conducted by independent scientists as opposed to industry scientists when it comes to the question of Roundup. How correct is that?

HANSEN: Well, that is actually fairly correct. There was an article published in 2011 in the Journal of Food Policy that was actually very interesting because it looked at this issue of conflict of interest, both financial conflict and professional conflict of interest. And for articles in which there was a professional conflict of interest, there were 41 studies, and that means one or more of the authors in each of the studies worked in the industry. Of those 41 studies, every single one of them found no problem. For studies where there was not a professional conflict, that is where none of the authors came from industry, there were 51 studies, 12 of them found problems. That was a highly statistically significant difference, the probability of that happening by chance was less than one in 1000, was less than .001. So what that suggests is that if a study on GMOs involves an industry scientist, if they’re an author on it, it will invariably find no problem at all with the GMO….



The health effects of a Roundup-tolerant NK603 genetically modified (GM) maize(from 11% in the diet), cultivated with or without Roundup application and Roundupalone (from 0.1 ppb of the full pesticide containing glyphosate and adjuvants) indrinking water, were evaluated for 2 years in rats. This study constitutes afollow-up investigation of a 90-day feeding study conducted by Monsanto in orderto obtain commercial release of this GMO, employing the same rat strain andanalyzing biochemical parameters on the same number of animals per group as ourinvestigation. Our research represents the first chronic study on thesesubstances, in which all observations including tumors are reportedchronologically. Thus, it was not designed as a carcinogenicity study. We reportthe major findings with 34 organs observed and 56 parameters analyzed at 11 timepoints for most organs.


Biochemical analyses confirmed very significant chronic kidney deficiencies, forall treatments and both sexes; 76% of the altered parameters were kidney-related.In treated males, liver congestions and necrosis were 2.5 to 5.5 times higher.Marked and severe nephropathies were also generally 1.3 to 2.3 times greater. Infemales, all treatment groups showed a two- to threefold increase in mortality,and deaths were earlier. This difference was also evident in three male groups fedwith GM maize. All results were hormone- and sex-dependent, and the pathologicalprofiles were comparable. Females developed large mammary tumors more frequentlyand before controls; the pituitary was the second most disabled organ; the sexhormonal balance was modified by consumption of GM maize and Roundup treatments.Males presented up to four times more large palpable tumors starting 600 daysearlier than in the control group, in which only one tumor was noted. Theseresults may be explained by not only the non-linear endocrine-disrupting effectsof Roundup but also by the overexpression of the EPSPS transgene or othermutational effects in the GM maize and their metabolic consequences.


Our findings imply that long-term (2 year) feeding trials need to be conducted to thoroughly evaluate the safety of GM foods and pesticides in their full commercial formulations….

Study Linking GMOs and Tumors Vindicated Yet Again…MSM Stays Silent