The European Food Safety Authority has published its review of a controversial study which revealed rats fed on genetically modified maize developed tumours at a much higher rate than a control group. The study, released last month, was conducted by a French professor of microbiology, Gilles-Eric Séralini, and was published in a peer reviewed journal.

image expired

Seralini’s study is the first to measure the effects of feeding rats on a diet of GM maize throughout their entire lives; the professor had claimed that EFSA risk assessment testing, which measures the effects of consumption of GM material over a much shorter period, is insufficient. However, when his study was released in September, it attracted negative attention from several scientists almost instantly; Professor Seralini’s shrewd behaviour at the time of the release was also the subject of much discussion.

Following an initial review carried out at the request of the European Commission, the EFSA concluded on Thursday (4th October) that Seralini’s paper, which suggests a variety of GM maize (NK603) and glyphosate herbicide could have toxic effects, “is of insufficient scientific quality to be considered as valid for risk assessment.”

The food safety watchdog said it would continue its investigation into the research. The Authority’s review is only a preliminary measure in a longer process; a full analysis of the paper is expected to be released later in October.  

EFSA said that, as “the design, reporting and analysis of the study, as outlined in the paper, are inadequate,” it has invited Séralini and his research team to share further information. EFSA concluded in a statement on Thrusday that “The numerous issues relating to the design and methodology of the study as described in the paper mean that no conclusions can be made about the occurrence of tumours in the rats tested.”

Per Bergman, who led the Authority’s work commented, “Some may be surprised that EFSA’s statement focuses on the methodology of this study rather than its outcomes; however, this goes to the very heart of the matter. When conducting a study it is crucial to ensure a proper framework is in place. Having clear objectives and the correct design and methodology create a solid base from which accurate data and valid conclusions can follow. Without these elements a study is unlikely to be reliable and valid.”

Main findings of Initial Review

The EU investigators who carried out the scientific assessment of the study raised a number of points of contention, which they said would need to be addressed before “[the research] could be viewed as well-conducted and properly-reported study.”

The EFSA scientists pointed out that the rats used by Seralini and his team are susceptible to the development of tumours, a fact which is not discussed in the research; Seralini’s supporters, on the other hand, claim most industry feeding studies use this type of rat. The EFSA also claim that some of the rats did not have a control group to measure against and questioned Seralini’s use of test groups eighty percent smaller than the OECD recommended group size (10 animals per group, as opposed to 50).

The French researchers’ methodology and lack of stated aims were also called into question. EFSA investigators also said, “Many endpoints – what is measured in the study – have not been reported in the paper. This includes relevant information on lesions, other than tumours, that were observed. EFSA has called on the authors to report all endpoints in the name of openness and transparency.”

However, Seralini and his supporters contend that the immediate response to his study, especially from sceptical scientists who offered condemnation just hours after its publication, and who have been widely quoted in the mainstream press, exposes the “fundamental challenges faced by science in a world increasingly dominated by corporate influence.”

Seralini supporters issue open letter in defence

In an open letter signed by an international coalition of scientific experts and published in Independent Science News, Seralini’s supporters state that the challenges his research has faced “are important for all of science but are rarely discussed in scientific venues.”

The scientists make mention of previous attempts to discredit researchers who have gone up against transnational agribusinesses, criticise current risk assessment practice and decry governments’ use of science “as a political football.”

In the letter, published on Tuesday (2nd October), the experts take aim at the EFSA and hint at the existence of an agricultural-industrial complex. They conclude that “When those with a vested interest attempt to sow unreasonable doubt around inconvenient results, or when governments exploit political opportunities by picking and choosing from scientific evidence, they jeopardize public confidence in scientific methods and institutions, and also put their own citizenry at risk.”

On the topic of NK603 they state, “If the starting point of a scientific product assessment is an approval process rigged in favour of the applicant, backed up by systematic suppression of independent scientists working in the public interest, then there can never be an honest, rational or scientific debate.”

While the EFSA said it does not currently believe Professor Seralini’s research provides grounds for it to revisit its assessment on NK603 maize, in a letter to the Professor EFSA said, “In a second output EFSA will take into account information received [from the authors and] an overview of assessments made by member states.”

The EFSA’s review is available here

Tweet