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for a responsible, fair & sustainable food system

European Scientists: EU GM Crop Safety Testing Flawed

Immediate release (5 Oct 2012)

Calls to: Pete Riley, GM Freeze 07903 341 065

The European Network of Scientists for Social and Environmental Responsibility (ENSSER) today responded to the criticism levelled at the recent research paper reporting the results of the long-term feeding of GM maize to rats. [1] The statement points out that the same criticism could be applied to tests carried out by Monsanto, which are used of proof of safety by the European Food Safety Authority (EFSA).

The response follows the 4 October publication of the EFSA GMO Panel’s initial response to the experimental results of CRIIGEN’s work by a team led by Professor Gilles-Eric Séralini. It details arguments raised against the CRIIGEN work and explains why they don’t stand up.

ENSSER welcomed CRIIGEN’s scientific paper and notes that the work follows on the lab’s study of the data submitted by Monsanto to EFSA in support of the application to market the company’s own GM maize. This analysis indicated toxicological effects in liver and kidneys in a 90-day oral feeding trial conducted by the company. [2]

Séralini’s team’s latest experiment extended the length of the trial to two years (ie, lifetime exposure) using various treatments and compared results with untreated controls. [3] The prolonged exposure to GM maize and Monsanto’s weedkiller Roundup (using the chemical glyphosate as an active ingredient) produced a similar, but more serious, impact on the kidneys and livers in male rats.

ENSSER concludes:

After a careful comparative analysis of both industry published data and that of CRIIGEN, ENSSER concludes that most arguments which attempt to invalidate the Séralini et al. study cannot hold up to closer scrutiny. Raised criticisms are to a large extent either wrong or apply double standards.

The group acknowledges that the Séralini study is not perfect:

The weak point of the pilot study by Séralini et al. is the number of animals used, which does not allow a statistical analysis of the raw data regarding one parameter measured out of over 30 – mortality. This has been acknowledged by the authors and needs to be considered/remediated in follow-up studies.

Yet ENSSER clearly points out:

  1. EFSA had already approved the GM maize (NK603) and its associated use of the herbicide glyphosate as safe in 2009 [5], so “their credibility is at stake” if they were to concede that the extended rat feeding trial conducted by CRIIGEN raised significant concerns about the crop’s safety. A clear case of conflict of interest.
  2. The CRIIGEN trials followed OECD guidance for oral toxicity testing and used:
    • The same breed of rats as Monsanto.
    • The same feeding method as Monsanto (free access).
    • The same procedures for monitoring the health and growth of the rats as Monsanto.

The Statement goes on to say:

All previous studies finding adverse effects of GE crops have been treated by regulators with: Only those studies showing adverse effects receive a rigorous evaluation of their experimental and statistical methods, while those that claim proof of safety are taken at face value.

ENNSER says critics of CRIIGEN have, “A long-documented record of rejecting the basic principles of the EU biosafety legislation and opposing the improvement of risk assessment standards.” The scientists are critical of, ”The proven close links between industry and EU risk assessors and the documented, disproportional influence on regulations by developers and owners of the technology.”

Pete Riley of GM Freeze said:

Professor Séralini’s team are to be congratulated on a genuine attempt to unearth the facts about the safety of GM crops. They exposed the double standards of the regulators and those who clamour for the deregulation of GM crop approvals. There are clear flaws in the EU’s GM crop approval process that urgently need addressing, but EFSA is not the right body to do this.

The obvious next steps are: 1) For a review and overhaul of the statutory risk assessment process by a group with no vested interests, and 2) For an independent group to carry out further long-term toxicological trials on GM crops building on what the CRIIGEN team have done.

In the meantime we need a freeze on all GM imports with the RR trait, as well as on any future approvals for either cultivation or import.



[1] ENSSER, 4 October 2012. “Review of the Séralini et al. (2012) publication on a 2-year rodent feeding study with glyphosate formulations and GM maize NK603 as published online on 19 September 2012 in Food and Chemical Toxicology”. Available at CRIIGEN 2012 study: Long-term health impacts of GM and Roundup

[2] Séralini et al, 2009. “A Comparison of the Effects of Three GM Corn Varieties on Mammalian Health”. Int J Biol Sci 5:706-726

[3] Séralini G-E, Clair E, Mesnage R, Gress S, Defarge N, Malatesta M, Hennequin D, Spiroux de Vendômois J, 2012. “Long term toxicity of a Roundup herbicide and a Roundup-tolerant genetically modified maize”. Food and Chemical Toxicology (copy available on request)