Questions about the In Vivo study

When it was published, the long-term (two years) in vivo toxicological study on NK603 GM maize, and its associated pesticide Roundup, also tested on its own, received worldwide media exposure, raising many questions about this ground-breaking scientific work. Study protocol, rat strain, dosage... In this article, Prof. Séralini and his team of researchers answer point by point all the questions about their study.

 What is the magnitude of the difference in mortality between controls and the historical norm?

As each experiment has its own specific conditions, the historical norm is too broad to be a relevant comparison. The controls are in the normal life average, and our differences are in relation to the experiment controls.

How do you explain the absence of biochemical signs in males?

Yes, there are. Not all the results are presented in the study, however, as this was impossible given their number. There is always a chronological difference between biochemical disturbances, the first ones, and pathological lesions, which we observe in both sexes. In males, the pathological lesions were earlier and more significant than in females at hepatorenal level, and it is these lesions that are presented.

The same differences are found in all treatments, so how do you know it's not your controls that are abnormal? Or that it's not due to chance?

Our controls correspond to the values observed in the species. The pathological observations have logical explanations for all treatments, are consistent and numerous enough not to be linked to chance; the statistics pushed to biochemical level are concordant and show it. Our in vitro studies concur.

How can you be sure that such a low depletion of ferulic and caffeic acids explains such a wide range of pathologies?

For us, these are understandable indicators of the variations in maize metabolism that may have taken place, and very interesting logical leads in relation to the scientific literature and our work. They in no way exclude the action of other toxic metabolites due to the GMO, which is why we are requesting funding for proteomic and transcriptomic analyses. To find out more about the crucial details of event mechanics.

Do you have any interesting results for Roundup tissue assays, microbiology and transgene assays?

Yes, we do have some results that need to be completed, and which give us some very interesting leads that will be published at a later date. Several publications are planned after this initial work.

Why use the threshold of 17.5*17.5 mm in males and 20*20 mm in females to count tumors?

This is the size threshold above which over 95% of tumors are non-regressive.

What is the basis for the pathogenesis criteria used in table 2? Which classification did you use?

By differential elimination of the smallest differences. Anatomopathology studies were carried out on a blind basis. They corroborate biochemistry and mortality observations.

Have you measured glyphosate residues in NK603 or kibbles?

Yes, we checked its use and the presence of all pesticides. Values were below regulatory thresholds. The limits of quantification in the different matrices are different.

You mention an effect on oxidative stress in rats due to your treatments. Are oxidative stress markers disrupted?

Yes, for cytochromes in the liver, and GST too, for example.

Was the corn sprayed with other pesticides? Did you find any other residues?

Yes, normally, including a fungicide. These were not organic crops that we could test later. There are no pesticides above quantification thresholds in food.

Not all tumors are cancerous. Why did you count everything at once?

In this first publication on this study, we have counted all the non-regressive tumors that most often lead to death. Non-cancerous tumors had more serious repercussions than internal carcinomas, because they compressed organs, caused hemorrhage, etc. The grade of the cancer was not related to mortality. Cancer grade was not related to mortality. We'll go into more detail by organ in later publications. Of course, we have had cancers that are indicated in the article, even in the photo captions.


Do the results you found in this study correspond to the disturbances found in the subchronic tests reanalyzed previously in your publications, which Monsanto under-interpreted?

Yes, these are signs of hepatorenal toxicity that were previously published after only 90 days of treatment, and which are firmly declared as pathologies in our long-term experience.

Do you think these pathologies can be transposed to humans?

Very generally, yes, but not all. In fact, the slightest sign of toxicity in rats must be taken into account when banning a product. For 50 years, studies have been carried out on rats or human cells for products not tested on humans (where only drugs are tested, not GMOs, pesticides or chemicals). And for drugs, tests on rats or 2-3 mammals precede any clinical trials. If they show serious effects, humans are not treated afterwards. Hormonal disruptions are in any case relevant in women for contributing to breast tumors, and hepatorenal effects have been found in vitro on human cells.

Why do you quote Zhang et al.'s 2012 reference? This reference is not about GMOs.

One hypothesis is that novel microRNAs produced by GMOs may interfere with metabolism. We couldn't ignore it, but we have other explanatory hypotheses.

How do you explain the fact that the effects presented are not found in human populations? Has no one ever noted an increase in breast cancer in populations exposed to Roundup?

There is an explosion in the number of breast tumors, which is not explained by epidemiological studies. We remind you that since GMOs are not labelled, the consumption of GMOs in the USA is not recorded, nor is the use of Roundup worldwide.

Do the concentrations of ferulic acid found correspond to those indicated in Monsanto's experiment?

Unfortunately, Monsanto did not measure hepato-renal and mammoprotective acid concentrations directly in the diet, but only once for ferulic acid in GMO and control corn.

You say that 76% of parameters are disturbed in the kidney. How does this indicate toxicity? I don't understand this method.

We count all the disturbed parameters against the controls and compare the number of parameters related to renal activity against all the parameters. We have 48% renal parameters among all the parameters measured, yet 76% of the disturbed parameters are markers of renal activity! Any doctor would freak out over a patient in this situation. (In one of our previous publications, this figure was 42% of disturbed parameters, for 24.9% measured, in the male kidney and for consumption in an average quarter on 19 GMOs; regulatory tests). The kidney is 1.5 times more affected than other organs.

Roundup increases lifespan in males? Isn't that the best indicator of the herbicide's safety? This increase is even dose-dependent. Strangely, you don't mention this. Why not?

We leave this misleading interpretation to you! The treated males were sicker than the controls in any case, even if in 1 case out of 6 treatments (3 in males + 3 in females) there was no excess mortality for any dose before the average life expectancy. These rats do lose weight, however (we'll look at this in another publication), and this may give them a certain resistance.

Have you compared your results with those of Sakamoto's Japanese study or another? Contrary to what you say, you are not the first to have studied the safety of a GMO for 2 years.

Yes, none of them has been as detailed as ours, and none of them has dealt with NK 603 corn beyond 3 months.

You carried out the study in a GLP environment. Is the study classified as GLP? If it isn't, doesn't that discredit it?

There was no standard protocol for this type of lengthy study with GMOs, and we're establishing and improving it, which is a world first. So there could be no pre-established standard for this type of test. What's more, it's a research protocol in which we've added ongoing biochemical and microscopic analyses to understand what was going on. Now it can serve as an example for establishing GLP standards for GMOs, much more serious than what health agencies do today, which work neither scientifically nor honestly. However, this work was of course carried out in a GLP environment.


Pr. Séralini's team.

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