19 comments on “Another Anti-GMO Scare Tactic Bites the Dust

  1. Hi Julee;

    I fear you are right that this study won’t go quietly into that good night. Did you notice that, not once, did Seralini publish pictures of the control rats with those of the 3 he did?

    • With all due respect, I could say the same about you. I don’t find GM Watch to be a credible website. I ‘regurgitate’ what the mainstream says because it is the truth. Why would I say something other than what I believe to be true?

      The Seralini study had major flaws and was not conducted using proper scientific protocols. For example, the control group was not mentioned, let alone shown. Had it been included, there would have been multiple tumors as well because it is a norm of this particular species to grow tumors.

      This is science 101. Something even I can understand. The study is a joke to scientists. Pure trash. If these tumors really grow as a result of GM food, then Seralini should repeat the study and do it right this time. Oh but, wait, it isn’t possible to repeat so better to just cry foul and sue. He may indeed win the lawsuit, but that doesn’t make the study any better.

      Oh wait, were those my own words? Why yes, they were.

      • LOL !

        2+2 =4

        “You’re just repeating corporate mainstream math !” – anti-gmoer.

    • I’ll comment. One link goes nowhere, but the other just says the journal didn’t make a proper decision and defends the Seralni paper. It is on GM Watch, your blog, and the blog that also says so many things about me, my approach to research, and allegations of lax standards. It is an baseless personal attack that strives only to discredit me and my record, which has never been questioned by anyone in science– not even close. GMWatch is an activist fringe site that hates science and scientists that don’t regurgitate the anti-GM line.

      Of course, the blog loves Seralini, which I think is great. Enjoy. If his work is so spot on it would intermesh with research from all over the globe, new labs would find comparable results, people would understand the mechanism by which tumors were induced (by an enzyme used in amino acid synthesis that has the exact activity as the existing corn enzyme). Just like any of his papers, it will be a scientific dead end, dead to science and scientists, but loved and adored as stellar-perfect evidence by GM Watch and activists everywhere.

      • Without commenting on the articles you immediately employ an ad hominem attack on the source.

      • The Editor-in-Chief of Food and Chemical Toxicology, A. Wallace Hayes, has come under severe criticism after retracting from his journal the paper by Seralini et al on the long term toxicity of Roundup and a Roundup-tolerant GM maize. He has now published a defence of the retraction, which we reproduce below.

        Here are some of the major problems with Hayes’ defence of his retraction decision:

        1. Hayes states that Dr Seralini’s “claim (ie, conclusion) that Roundup Ready maize NK603 and/or the Roundup herbicide have a link to cancer is unreliable” because the data on this are “inconclusive”. He goes on to say that “Dr. Séralini deserves the benefit of the doubt that this unreliable conclusion was reached in honest error. The review of the data made it clear that there was no misconduct. However, to be very clear, it is the entire paper, with the claim that there is a definitive link between GMO and cancer that is being retracted.”

        BUT there is no claim or conclusion in the paper “that Roundup Ready maize NK603 and/or the Roundup herbicide have a link to cancer”; nor does the “entire paper” “claim that there is a definitive link between GMO and cancer”. IN FACT, THE ENTIRE SERALINI PAPER DOES NOT MENTION THE WORD “CANCER” ANYWHERE!

        This was a long term toxicity study – the clue is in the title: “Long term toxicity of a Roundup herbicide and a Roundup-tolerant genetically modified maize”. Seralini did not set out to look for carcinogenicity, or to conduct a carcinogenicity study. He has said he did not expect to find evidence of carcinogenicity, but he did find evidence of tumours in the treatment groups during the study, which he reported, as he should. Tumours unexpectedly found in a chronic toxicity study MUST be reported according to OECD452 chronic toxicity protocol (“lesions”), so Seralini had to note them in the paper. But he noted them without drawing definitive conclusions or extrapolating his findings to human carcinogenicity.

        His toxicity study has now been retracted on the grounds of claiming “a definitive link between GMO and cancer”, which it nowhere makes. So, did Hayes actually read the Seralini paper before retracting it? Because if he did, how come he doesn’t know what the paper says?

        Hayes not having read the paper is, of course, the charitable interpretation of his actions, because if he is familiar with the paper’s contents it might be hard not to conclude that he has deliberately misrepresented them.

        2. Hayes defends the study done by Monsanto (Hammond et al., 2004) which his journal also published, but which it has not retracted. The Monsanto study, Hayes says, included 20 rats per sex per group, whereas Seralini et al only included 10 rats per sex per group. But what Hayes fails to acknowledge is that the Monsanto study only *analysed* 10 rats per group (i.e. 50% of the animals) for blood and urine chemistry (the main chronic toxicity endpoints), meaning selection bias was introduced. Seralini used 10 per sex per group in total, so just as many animals per group were analysed without any possibility of selection bias. Thus, Seralini’s methodology was more rigorous than that of Monsanto’s, while generating just as much data per group.

        3. Hayes admits the chronic toxicity findings are justified by a study of the size that Seralini et al carried out. In that case, why not simply ask Seralini to publish a clarification to his paper to the effect that the “chronic toxicity findings statistics are significant; tumour findings need followup”, if that is what is felt to be necessary? That is the correct approach according to the Committee on Publication Ethics (COPE) guidelines that Hayes claims to be abiding by. There is nothing in the COPE guidelines that justifies or requires the retraction of the whole paper.

        4. Hayes argues that his appoinmtment of a former Monsanto editor (Richard Goodman) as an Associate Editor at his journal (FCT) with particular responsibility for biotechnology, could not have been a biasing factor in the (re)review of the Seralini paper that led to its retraction. Hayes claims that part way through the (re)review of Seralini’s data, Seralini requested that Goodman not take part in this process and that Hayes readily agreed to this.

        BUT Hayes also admits that, “Professor Goodman, along with all other members of the editorial board was involved in initial discussions of the Séralini paper and the request to view raw data.” The fact that this former Monsanto employee was involved in discussion of the (re)review of the Seralini paper from the start, and up until Seralini directly requested that this stop, means that he could not only have influenced the discussion but even more crucially the selection of the review panel members. This is especially the case because we know Goodman was appointed by Hayes in the light of his criticisms of the Seralini paper and as having particular expertise in this area, all of which suggests that Hayes would have been likely to take his views into account.

        Food and Chemical Toxicology Editor-in-Chief, A. Wallace Hayes, Publishes Response to Letters to the Editors

        Cambridge, MA, December 10, 2013

        The following statement will be published in the journal, Food and Chemical Toxicology, alongside a selection of letters to the editors regarding the decision to retract the paper by Séralini et al.(Séralini et al., 2012).

        In November 2012, this journal published an article titled “Long term toxicity of a Roundup herbicide and a Roundup-tolerant genetically modified maize,” by Séralini et al.(Séralini et al., 2012). The publication of this article caused quite a stir in the media, as well as in the scientific community. The journal received many letters expressing concerns about the validity of the findings. A careful and time-consuming analysis found that the data were inconclusive, and therefore the conclusions described in the article were unreliable. Accordingly, the article was retracted. Since the public announcement of the retraction, the journal has received many letters to the editor; a selection of these letters will be published, along with this response to those letters. Many of these letters expressed concerns about the decision making process behind this action, particularly what role (if any) current or former Monsanto employees played, whether or not COPE guidelines were followed, and if the journal was also considering retraction of a similar paper by Hammond et al.(Hammond et al., 2004). The answers to these questions are below.

        The membership of the editorial board is composed of academic, government, and industrial scientists. Contrary to what has been suggested by some, the appointment of Professor Richard Goodman, University of Nebraska, as an Associate Editor was not influenced by Monsanto or any other party. Members of the editorial board are chosen based on their expertise as scientists. It is the goal of this journal to have a variety of different viewpoints. In this case, as in other cases, I as Editor-in-Chief listened to as wide and diverse a set of expertise as possible. To wit, Professor Goodman, along with all other members of the editorial board was involved in initial discussions of the Séralini paper and the request to view raw data. When the request was made to Dr. Séralini to review the raw data, the journal suggested to Dr. Séralini that all parties involved sign a confidentiality agreement. This confidentiality agreement was designed to protect Dr. Séralini and his data so that it was (A) not viewed by anyone he did not want to view his data and (B) that it would not go beyond the people he agreed would review the raw data. Not initially, but during the process, Dr. Séralini made a direct request that Professor Goodman be excluded, and we at FCT readily and quickly agreed. It is understandable that Dr. Goodman’s involvement, however small, might be cause for concern for some. However, the decision to retract the paper was mine alone, made by me exclusively and not by a vote of the editorial board. Further, when Dr. Séralini asked for Dr. Goodman’s involvement to stop, I agreed, fully and promptly.

        The Monsanto Company did write a letter to the editor regarding this article, and it was published along with a number of other letters to the editor (Hammond et al., 2013); neither the company nor any of their scientists put any pressure on the Editor in Chief regarding this matter.

        A second concern that has been raised is whether this retraction follows the COPE guidelines. The COPE guidelines were consulted when making this decision. According to the COPE guidelines, “Journal editors should consider retracting a publication if… they have clear evidence that the findings are unreliable, either as a result of misconduct (e.g. data fabrication) or honest error (e.g. miscalculation or experimental error).”(COPE, 2009). The retraction statement could have been clearer, and should have referred to the relevant COPE guidelines. The data are inconclusive, therefore the claim (ie, conclusion) that Roundup Ready maize NK603 and/or the Roundup herbicide have a link to cancer is unreliable. Dr. Séralini deserves the benefit of the doubt that this unreliable conclusion was reached in honest error. The review of the data made it clear that there was no misconduct. However, to be very clear, it is the entire paper, with the claim that there is a definitive link between GMO and cancer that is being retracted. Dr. Séralini has been very vocal that he believes his conclusions are correct. In our analysis, his conclusions cannot be claimed from the data presented in this article.

        At this point it is very important to state that the retraction does not reflect or impact the journal’s view on GMOs or associated organizations. Our journal would, in fact, very much welcome the opportunity to review follow-up studies that have a greater sample size, a fine-tuned method, and proper controls. We are also actively searching and recruiting people to provide a balance view on this topic to serve on the editorial board.

        Finally, the letters post-retraction have questioned whether an earlier study done by Monsanto received different treatment from our journal. This article was published in 2004, well before I became Editor-in-Chief. However, I take the issue seriously and have reviewed this paper in detail. The Hammond et al. article was a 13 week feeding study performed in rats feed grain from Roundup Ready corn which is tolerant to the herbicide glyphosate (Hammond et al., 2004). The authors reported the following: “Purina TestDiets formulated Roundup Ready corn grain into rodent diets at levels of 11 and 33% (w/w). The responses of rats fed diets containing Roundup Ready corn grain were compared to that of rats fed diets containing non-transgenic grain (controls). All diets were nutritionally balanced and conformed to Purina Mills, Inc. specifications for Certified Lab Diet 5002. There were 400 rats in the study divided into 10 groups of 20 rats/sex/group. Overall health, body weight, food consumption, clinical pathology parameters (hematology, blood chemistry, urinalysis), organ weights, gross and microscopic appearance of tissues were comparable between groups fed diets containing Roundup Ready and control corn grain… This study complements extensive agronomic, compositional and farm animal feeding studies with Roundup Ready corn grain, confirming it is as safe and nutritious as existing commercial corn hybrids.” The authors also stated “The study design was adapted from OECD Guideline No. 408 (1981) and the study was reported to have been conducted in general compliance with OECD Good Laboratory Practice (GLP) guidelines at the Metabolism and Safety Evaluation-Newstead, toxicology laboratory.”

        In accordance with OECD Guideline No. 408 (OECD, 2009a), the Hammond et al. study was limited to 90 days following and used 20 rats/sex/group, and was conducted in general compliance with OECD Good Laboratory Practice (GLP) guidelines, as previously stated. The Séralini et al. study ran for two (2) years with only 10 rats/sex/group and was reported to be done in a GLP environment according to OECD guidelines (which guideline is not explicitly stated in the paper). Séralini et al. state that they had “had no reason to settle at first for a carcinogenesis protocol using 50 rats per group,” as recommended in OECD Nos. 451 and 453 (guidelines for Carcinogenicity Studies and Combined Chronic Toxicity/Carcinogenicity Studies, respectively)(OECD, 2009a; OECD, 2009b), and instead seem to have opted for 10 rats/sex/group as recommended by OECD No. 408 (guidelines for Repeated Dose 90-day Oral Toxicity Study in Rodents). While the number of animals used may have been sufficient to reach conclusions regarding oral toxicity, it proved insufficient for conclusions related to the carcinogenicity of the test substances.

        In conclusion, FCT has retracted this article because our thorough investigations revealed that its methods were scientifically flawed. The low number of animals, and the strain selected, rendered the conclusions unreliable. No definitive conclusions could be drawn from the inconclusive data. Therefore, in accordance with both the COPE guidelines and the journal policy, it was necessary to take this action of retracting the article.

        A. Wallace Hayes, PhD, DABT, FATS, FIBiol, FACFE, ERT
        Registered Toxicologist (France and EUROTOX registries)
        Harvard School of Public Health
        Editor-in-Chief, Food and Chemical Toxicology


        COPE, 2009. Retraction guidelines.
        Hammond, B., Dudek, R., Lemen, J., Nemeth, M., 2004. Results of a 13 week safety assurance study with rats fed grain from glyphosate tolerant corn. Food Chem. Toxicol. 42, 1003–14.
        Hammond, B., Goldstein, D. a, Saltmiras, D., 2013. Response to original research article, in press, corrected proof, “‘Long term toxicity of a Roundup herbicide and a Roundup-tolerant genetically modified maize’”. Food Chem. Toxicol. 53, 459–64.
        OECD, 2009a. OECD Guideline for the Testing of Chemicals.
        OECD, 2009b. Combined Chronic Toxicity \ Carcinogenicity Studies.
        Séralini, G.-E., Clair, E., Mesnage, R., Gress, S., Defarge, N., Malatesta, M., Hennequin, D., de Vendômois, J.S., 2012. Long term toxicity of a Roundup herbicide and a Roundup-tolerant genetically modified maize. Food Chem. Toxicol. 50, 4221–31.

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  2. FO – illogical reasoning.

    The EFSA was recently shown to have serious conflicts of interest, a source you cite. It was a very thorough report, yet you continue to ignore these claims because it is inconvenient and doesn’t agree with your current beliefs. You have yet to comment on it. That isn’t in search of truth, and it is well known that much of the mainstream is funded by corporations. Much of “science” is. So to think there is not a vested interest in protecting profits is naive. Disregarding information without analyzing the information is the opposite of a scientific, logical mind. You subscribe to groupthink, strawman attacks, and information bias. There are logical arguments presented in the two links, yet you refuse to address them so you skip them, saying the entire site is not credible, and therefore, not worthy of a response. There may have been information presented on the site that was incorrect or biased at some point. Does it mean all information is biased and incorrect? No it doesn’t. You must review the information on a case by case basis. But you dont do that. When your camp says these people are bad, you go along with it. By disregarding entire sources which oppose your groupthink, you are not searching for truth.

    Anyone can paraphrase something said against the seralini study. Why dont you read those articles and comment on the points they mention.

    • Claire, “Disregarding information without analyzing the information is the opposite of a scientific, logical mind”– maybe a little self-application of this? The Seralini paper does not have complete controls, conveniently omitted, they fail to mention that there are strong statistical limits on their work and even little things like glyphosate-treated rats in some groups live longer (due to bad statistics, not a biological effect, IMHO).

      If there’s any place where groupthink, strawman attacks, and information bias are alive and well it is in the anti-GM movement. Wow.

      I’m perfectly glad to switch my thinking on this topic when presented with real data. That’s how I make decisions. I just haven’t seen any yet that is both compelling and repeated.

      Seralini will be vindicated when someone else produces research with sufficient numbers and interpretations within the data that are consistent with his findings. I’m not holding my breath. Seriously, if there was a problem here science would be all over it.

      • I am not Claire and it is not my blog. Information bias is everywhere: in governments, industry, academia, etc. Like I posted in response to Jules below, read the articles (they both work fine for me) and tell me which points they bring up that are incorrect or false. Its not difficult to analyze a short article. Stop repeating problems with the seralini study and address what is written in the article. I am looking for what is wrong im those articles, both of which are live. I will copy and paste them since instead of addressing what is actually written,you first made an attempt to discredit the source, a logical fallacy.

      • I dont think you completely read my post. I directly acknowledge that no source is above critical review, and state “…There may have been information presented on the site that was incorrect or biased at some point. Does it mean all information is biased and incorrect? No it doesn’t. You must review the information on a case by case basis…”

        That was with reference to gmwatch, in case it was not clear. You also are guilty of dodging what it is I am asking you to address and repeating an attack on the paper. I get it, you dont like it. What about I i posted, because if I need to say it, I didn’t post the seralini study here, I posted two short links and asked the author and now you to weigh in on what was stated.

  3. If something in those two articles is not credible, post it. Don’t ignore it and then repeat mainstream mantras against the seralini study.

  4. Transgenesis are you really that unaware that your anti-GMO crowd and it’s surfeit of websites are ALSO a big giant groupthink (your word not mine) with an agenda? GM Watch is an activist website with acitivist agendas and activist spins in every article published. The very thing you continually accuse me of is so blatantly in your own wheelhouse it is laughable to me.

    When you accuse me of not looking for the truth, I am not offended because I truly believe you have been sadly and grossly mislead by a movement, not the facts. I’d rather have mainstream science on my side any day, and it is.

  5. im aware when you receive information from certain sources, it may be subject to their opinions or influenced in a such a way that the information is not truthful, reliable, etc. Notice nowhere have I mentioned or stated that gmwatch was the most objective there is. What I have said is that you must evaluate information and statements based on the content, not the source of publication, something you still dont seem to understand.

    Do i dismiss journals because they publish something i think is biased or influenced by industry? No of course not, i dismiss said piece of information. How can you truthfully and honestly question your own beliefs if you refuse to acknowledge someone or something that disagrees with your beliefs? if you do not question your own beliefs then you are not seeking the truth.

    You are using a strawman argument again, assuming i believe or said something and arguing against that, instead of acknowledging what i actually said, posted , or referenced. You are also guilty of ad hominin attacks against sources which you deem unworthy of analysis. You might have mainstream scienceas your basis of belief, but you lack logic and critical thinking, which to me is more important that what party you support.

    Notice you have yet to address points made in the articles i proposed. If i had paraphrased them and typed them out instead of posting a link to gmwatch, would you have addressed it then? Are you scared to acknowledge information from someone in the opposite camp?

    The statement “id rather have mainstream science on my side” shows you have picked a side and made up your mind regardless of any argument put forth. When presented with information you are still refusing to address or acknowledge it.

    I use logic in my thinking and analysis, i dont subscribe to a belief and automatically dismiss everything hat doesn’t jive with it. i havent been mislead by anything, because i am not a follower.

    Yet again after another post, try to read the articles and tell me what your thoughts are on the information presented in them. Maybe i need to paraphrase them for you? Would that get you to participate in the debate?

  6. This was a poor display of “truth seeking” on your part. All this blog does is talk to like-minded individuals who are unable to question their own beliefs. This will be my last post since you are incapable of honestly looking at the situation from both sides. You’ve made up your mind regardless of any new information. If you expect Monsanto to come out and say “yes our products are harmful” and only will accept that as valid information, you are not a rational person.


    Food and Chemical Toxicology, the journal which recently retracted the infamous Seralini study, also published four safety assurance studies by Hammond et al.

    The feeding trial I will discuss on Sprague-Dawley rats (same rat strain as Seralini’s) by Hammond et. al. was published in 2004 and cited by Seralini, but curiously has not drawn any attention. It is the “mirror” piece of science that triggered Seralini’s investigation. The full text of the study is linked in the title.

    The study is a safety assessment to ensure that the Round Up Ready corn is as safe as conventional corn involving two components. Firstly, it is an evaluation of safety of the newly introduced trait, Round Up Resistance conferred by the Round Up Ready transgene (CP4 EPSPS). Secondly, it is an assessment for possible toxicity due to unintended pleiotropic effects resulting from the insertion of the transgene. [*]

    It is my opinion, the study does not provide robust evidence to support either claim and is just as inconclusive as Seralini, and should likewise be retracted. The following dissection should clarify the reasons why.

    Safety of introduced CP4 EPSPS trait

    Allergenicity of Round Up Ready(CP4 EPSPS) transgene protein has not been ruled out.

    Committees of global experts have created decision trees largely based on assessment of IgE-mediated food allergenicity for risk assessment.[8] The WHO guidelines state that a transgene with greater than 6 amino acid homology to a known allergenic epitope or > 35% of the sequence, should be further screened on 25 individual serum samples with high IgE titers to that air borne or food borne allergen.[2] CP4 EPSPS protein has homology of 7 contiguous amino acids ( 7 amino acid chain is clearly longer than 6) to a known and prevalent allergen- dust mite allergen (der p 7).[1]
    Hammond cites Harrison et al, a study on digestibility of CP4 EPSPS protein as evidence for lack of allergenicity of the introduced transgene. While digestibility is a preliminary step in screening novel proteins, it is not a substitute for immunologic studies. He also cites studies on Round Up Ready soybeans which allegedly do not show allergenicity, though they did not do a targeted analysis on serum from patients with dust mites allergies and thus would not uncover it in soybeans.The largest inhibition ELISA on CP4 EPSPS was reported for Round Up Ready soybeans on a trivial sample of 4. [9] Moreover studies on Round Up Ready soybeans are not a substitute for studies on Round Up Ready corn.

    Research to verify lack of cross-reactivity is not cited by Hammond et al, and a literature search failed to uncover such studies on 25 serum samples with high levels of IgE to dust mites.[9] Inhibition ELISA studies can and should be conducted to assess for the presence of allergenic cross-reactivity between the EPSPS CP4 protein in corn and der p 7 to definitively rule out allergenicity [10] This is a minimal standard of risk assessment for known allergens, while everyone accepts that even this standard leaves large gaps since not all allergies are IgE mediated.

    Toxicity due to pleotropic effects resulting from insertion into the corn genome [*]

    Random integration of a transgene may cause gene disruptions leading to sequence changes,
    production of new proteins or formation of new metabolites or altered levels of
    existing metabolites that could compromise safety. This includes the potential production of new allergens or toxins.[5] A proteomics study on maize demonstrated that 43 proteins were up- or down-regulated in transgenic seeds with respect to their controls specifically related to the insertion of a single gene into a maize genome by particle bombardment.[4]
    Non-targeted “omics” profiling studies might be able to detect unintended and unexpected changes that targeted compositional analysis underpinning the current risk assessment by Hammond et al would not, making this safety assurance study more conclusive. [11]

    Experimental design flaws

    Invalid reference groups.

    The experiment was conducted on 400 rats fed two doses of corn (11% & 33%). A balanced experimental design using 400 rats would consist of 50 rats/sex/dose on transgenic corn compared to 50 rats/sex/dose of its isogenic parent line grown side by side.

    See Table 1. Hammond’s reference groups A-F are grown in random geographic locales such as Indiana, Iowa and Colorado, while the genetically engineered corn was grown in Ohio!

    Agronomic factors (soil, fertilizers), and environmental influences (location, weather, stress) are factors that should be considered during “GE versus non-GE” evaluations. [3] The environment has been shown to play an important effect in the protein, gene expression and metabolite levels of maize samples tested, where 5 proteins, 65 genes and 15 metabolites were found to be differentially expressed.[5] Approximately 100 total proteins were differentially expressed as a consequence of environmental influence in a proteomics study. [4]

    Thus reference control A-F in Table 1 are inappropriate reference groups used to establish invalid reference ranges. Shrinking the experimental group to 80 (20/sex/dose) while increasing the control group to 320 animals serves to increase type II error (false negatives), reducing sensitivity of detecting adverse health effects.

    I could stop right here. If the reference ranges for non-GE corn are invalid, it isn’t possible to compare GE and non-GE for statistical differences within 2 standard deviations as the study does.
    But I shall go on.

    Data is reported for HALF the animals.

    Elementary school arithmetic for non-scientists. Number of animals (N) in Tables should be 20 because there were 20 rats/sex/group. Don’t feel too bad if you aren’t finding it easy, because the “esteemed” scientists and editors at Food and Chemical Toxicology evidently flunked elementary school arithmetic as well.

    There is a very good reason a system of blinding has been used for hundreds of years in research to prevent bias. Scientists often want a particular outcome from an experiment, and it is possible to choose the animals to test in such a way as to achieve desired results. In a non-blinded experiment, where the researchers know which animals are exposed to which food, and test results are published for half the animals ( N 4-10, instead of 20 in Tables 2,3,4), the researchers are free to cherry pick the rats based on overt clinical signs. If the transgenic corn was engineered with a metabolite toxic to the kidneys, the most affected rats would be identifiable, as they would be drinking excessively and urinating excessively. Rats with liver disease could likewise be avoided for sampling because their white skin would glow yellow due to jaundice. Bias does not have to be due to deliberate deception but due to human nature and strongly held beliefs.

    Data and conclusions of a non-blinded experiment reporting data for half the animals should be declared invalid by design.
    I could stop right here, but I shall go on.

    Statistics are invalid

    Tables 2-4 do not report precise number of rats. Means and standard deviations cannot be calculated for ranges of rats.

    A study with four times as many control/reference animals (N=320) as experimental (N=80) is intuitively grossly imbalanced which raises questions about the accuracy of the statistics cited. Unfortunately, statistics are not my strong suit.

    Kidney toxicity

    Sprague Dawley rats suffer from spontaneous kidney disease, chronic progressive nephropathy (CPN) which confounds toxicology studies. CPN primarily affects males and is felt to be exacerbated by ad libidum feeding and high protein diets.

    Blood tests associated with kidney function (BUN, creatinine) are not significantly elevated until advanced stages of disease, which makes the “normal” tests reported in Tables 4 & 5 meaningless.
    A urinalysis does indicate progression and loss of renal function by declining urine specific gravity, elevated levels of urine protein/ albumin, and casts- prior to elevation of blood tests.
    These inexpensive and crucial functional tests are not published in this study nor any Hammond et al feeding trial.
    I could stop right here, but I shall go on.

    The findings reported in Table 7 are vague and not descriptive of the specific histopathological changes. The earliest lesions of CPN in young rats are convolutions of a single proximal tubule showing basophilia and crowded nuclei, representing simple tubule hyperplasia, with thickened basement membrane (especially of the Bowman’s capsule), which is not reported in this study. The study instead reports mononuclear cell infiltrate, which is generally a feature of inflammatory/ immune mediated processes. However, CPN is not an inflammatory or vascular disease, and it has no immunological or autoimmune basis. [6]
    Regeneration is reported in 17/20 rats, which is disproportionately high to the number of animals in whom degeneration is reported, while these processes occur simultaneously. Thus without a review of histopathology slides by independent pathologists assurances of absence of reno-toxicity can not be made.

    Furthermore, pathologists recommend histopathological grading on a scale of 0-4 (kidneys graded by the study pathologist as minimal = 1 (less than 25% of renal tubules affected); mild = 2 (T 25–50%); moderate =3 (T 50–75%); or marked = 4 (T 75%); [7] [6] which likewise was not done in this study, making a valid comparison of severity between the groups impossible.

    In any case, sample sizes of 9-10 for whom results are published are too low to parse toxic effects fron confounding spontaneous kidney disease – unless the potential toxin has a very strong effect in a very short period of time.

    So, if you recall the main, and I believe, valid criticism of Seralini as having sample sizes too small to draw conclusions, the same is the case with this study. The sample size is too small to rule out kidney toxicity, separate and apart from the other flaws I listed above.
    The difference is that Hammond et al reaches the questionable conclusion that this GMO corn does not cause harm, even as half the laboratory animals disappeared, while Seralini accounts for all of his rats but concludes that the corn is harmful.

    I could stop right here, but I shall go on.

    Liver toxicity

    Tables 2,3,4 report normal liver enzymes which would suggest that the corn is not hepatotoxic. Unfortunately they do not.

    Liver enzyme tests are not liver function tests-they are tests of inflammation. In fact, liver enzymes can appear relatively normal in the face of liver failure. Bilirubin is a marker of jaundice most often associated with hepato-biliary disease. In cats the most common form of liver disease is known as hepatic lipidosis or fatty liver disease. The same disease is recognized in rats and in people, and it is called non-alcoholic fatty liver disease (NAFLD).
    Its prevalence rate is rising- especially among kids.

    I present an illustrative case report with blood work and a urinalysis in a cat with imminent liver failure, in whom liver enzymes were nearly normal. The test most crucial for diagnosis was serum and urine bilirubin.

    Total bilirubin (t.bili) in Table 4 is reported for 4-6 out of 20 male rats and 7-8 out of 20 female rats. Bilirubin values in the urine are not published for the rats at all. These are red flags!

    The study reports mulifocal chronic inflammation in most of the rats in Table 7 which could be histopathological indicators of chronic inflammatory hepatitis. Histopathological inflammation should cause elevation of liver enzymes, interestingly reported to be within normal ranges, which doesn’t really make sense.

    The liver represents a suitable model for monitoring effects of a diet, due to its key role in controlling the whole metabolism. A study examining effects of Round Up Ready soy diet were studied on liver of female mice in order to elucidate possible interference with ageing. Several proteins belonging to hepatocyte metabolism, stress response, calcium signalling and mitochondria were differentially expressed in GM-fed mice, indicating a more marked expression of senescence markers in comparison to controls. Moreover, hepatocytes of GM-fed mice showed mitochondrial and nuclear modifications indicative of reduced metabolic rate. The study demonstrated that GM soybean intake can influence some liver features during ageing while liver enzymes (the tests reported by Hammond et al) were not afffected at all. The mechanisms remain unknown, underlining the importance of investigating long-term consequences of GM-diets and the potential synergistic effects with ageing, xenobiotics and/or stress conditions. [12] [13]

    I hope I’ve clarified why this study by Hammond et al does not meet its stated goal of reassuring me of safety of this crop. The other three studies linked above relied on the same flawed experimental design.

    In spite of lack of ” conclusiveness” factor I outlined above, this study has not been retracted, which suggests that the agricultural biotechnology science establishment is promoting scientific double standards .

    I could go on — but I won’t. Hopefully, I’ve given you enough food for thought.


    1.BMC Structural Biology Screening of transgenic proteins expressed in transgenic food crops for the presence of short amino acid sequences identical to potential, IgE – binding linear epitopes of allergens Gijs A Kleter1 and Ad ACM Peijnenburg1
    E 2.Evaluation of Allergenicity of Genetically Modified Foods Report of a Joint FAO/WHO Expert Consultation on Allergenicity of Foods Derived from Biotechnology January 2001 Food and Agriculture Organization of the United Nations (FAO) Rome, Italy
    I 3. ISB NEWS REPORT • MAY 2010 Molecular Profiling Techniques as Tools to Detect Potential Unintended Effects in Genetically Engineered Maize. Eugenia Barros. http://researchspace.csir.co.za/dspace/bitstream/10204/4465/1/Barros1_2010.pdf
    4 4. J Proteome Res. 2008 May;7(5):1850-61. doi: 10.1021/pr0705082. Epub 2008 Apr 5. Proteomics as a complementary tool for identifying unintended side effects occurring in transgenic maize seeds as a result of genetic modifications. Zolla L, Rinalducci S, Antonioli P, Righetti PG.

    5. Comparison of two GM maize varieties with a near isogenic non-GM variety using transcriptomics, proteomics and metabolomics. Eugenia Barros,Sabine Lezar, Mikko J. Anttonen,
    , Jeroen P. van Dijk, Richard M. Röhlig, Esther J. Kok3, and Karl-Heinz Engel

    6.Toxicologic Pathology, 32:171–180, 2004A Contemporary Overview of Chronic Progressive Nephropathy in the Laboratory Rat, and Its Significance for Human Risk Assessment

    7. Toxicol. Sci. (2012) 128 (2): 346-356. Chemically Exacerbated Chronic Progressive Nephropathy Not Associated with Renal Tubular Tumor Induction in Rats: An Evaluation Based on 60 Carcinogenicity Studies by the National Toxicology Pgram Ronald L. Melnick, Kathleen M Burns, Jerrold M. Ward and James Huff http://toxsci.oxfordjournals.org/content/128/2/346.long

    8. Environ Health Perspect. 2003 Jun;111(8):1114-21.
    Clinical and laboratory investigation of allergy to genetically modified foods.
    Bernstein JA, Bernstein IL, Bucchini L, Goldman LR, Hamilton RG, Lehrer S, Rubin C, Sampson HA.


    10. Clinical and Molecular Allergy 2007; 5:2 Assessment of allergen cross-reactivity Rob C Aalberse

    11.Molecular profiling — a tool for addressing emerging gaps in the comparative risk assessment of GMOs Jack A. Heinemann, Brigitta Kurenbach,, David Quist http://www.sciencedirect.com/science/article/pii/S0160412011001322

    12. Histochem Cell Biol. 2008 Nov;130(5):967-77. Epub 2008 Jul 22.
    A long-term study on female mice fed on a genetically modified soybean: effects on liver ageing.
    Malatesta M, Boraldi F, Annovi G, Baldelli B, Battistelli S, Biggiogera M, Quaglino D.

    13. Cell Struct Funct. 2002 Aug;27(4):173-80.Ultrastructural morphometrical and immunocytochemical analyses of hepatocyte nuclei from mice fed on genetically modified soybean.
    Malatesta M, Caporaloni C, Gavaudan S, Rocchi MB, Serafini S, Tiberi C, Gazzanelli G.

    [*] The study as designed by Hammond et al does not permit evaluation for pleotropic effects since there is a confounding factor that has not been segregated out. The corn was treated with Round Up- a mixture of glyphosate, AMPA and proprietary adjuvants. These additional chemicals make it impossible to tease away any potential metabolic toxicity caused by transgene insertion on the genome from chemical toxicity of Round Up and its adjuvants. It is also the reason that Seralini in his retracted paper came up with the “complicated design” separating rats into groups exposed to transgenic corn alone ( to evaluate effects of transgene insertion on the genome in isolation of Round Up) and those exposed to Round Up in the drinking water.

    • When the scientific community in general is concerned about these studies, I’ll be concerned about them too. That is my short answer. I trust the experts because they can interpret data much better than I. Why would I trust my own interpretation over a PhD plant geneticist’s? Would you ask a person who can’t play the piano to perform a Beethoven sonata? Good science draws a crowd and is repeated, and when that happens I take notice and so do top-tier media outlets and journals. Until then, it escapes my radar. I know this isn’t the response you want, but it’s what I will offer. Keep in mind that I don’t have to publish your comments at all, but I do, out of respect for an opposing viewpoint.

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