Rat feeding studies with genetically modified maize - a comparative evaluation of applied methods and risk assessment standards

Abstract

A 2-year rat feeding study with genetically modified NK603 maize sparked an international scientific and public debate as well as policy responses by the European Commission. The European Food Safety Authority (EFSA) evaluated the study as defective based on conceptual and methodological shortcomings by retroactive application of the recommendations of its recent guidance on 90-day feeding studies. Our comparative analysis of the three relevant NK603 publications, including a 90-day feeding study of Monsanto, showed that all of them satisfy or fail to satisfy the EFSA evaluation criteria to a comparable extent; the rejection of only one of the papers is, thus, not scientifically justified. We also show that EFSA's criteria are not standard practice in 21 other rat feeding studies lasting at a minimum of 12 months. The review reveals critical double standards in the evaluation of feeding studies submitted as proof of safety for regulatory approval to EFSA. We specifically argue that the current approach to declare statistically significant differences between genetically modified organisms and its parents as 'biologically irrelevant' based on additional reference controls lacks scientific rigor and legal justification in the European Union (EU) system. Only recently, the EU authorities started building up an implementing system based on its own legislation and supportive of the EU approach to risk assessment in the context of technology assessment. Until these issues are resolved, we do not expect that neither the public nor the scientific debate will subside.

Outcome of the public consultation on the draft guidance on the agronomic and phenotypic characterisation of genetically modified plants

“…As we have described in previous commentaries, also published in Meyer and Hilbeck (2013) and, again, are repeating here, the 'comparative analysis' includes a hidden normative element and decision-making step at the technical level and intermingles it with statistical analyses solely on the quantitative nature of a data set that has been designed to contain a lot of unrelated 'noise', additionally, making the detection of differences that can be assigned to the GM component almost impossible -by design. This approach is scientifically questionable -certainly biased -and the normative dimensions are undeclared.…”

“…While over the past years, no norms, standards, and scientific criteria for the concept of familiarity and its core instrument of reference controls were developed, it is still at the discretion of applicants and authorities if and how to use the respective test results." (Meyer and Hilbeck 2013) Interestingly, EFSA again fails to determine scientifically sound selection criteria for choosing the non-GM reference varieties, which are the basis of the concept of 'familiarity'. To establish a 'natural variation' that could contribute somehow to EU environmental and health risk assessment the non-GM reference varieties should have relevance in the food and feed supply of the EU.…”

The Seralini affair: degeneration of Science to Re-Science?

“…Meyer and Hilbeck [21] have published an in-depth comparative analysis that included both Séralini et al [2] and Hammond, et al [4], which comes to the same conclusion.…”

“…These are not synonymous. Furthermore, as Schubert [19], Meyer and Hilbeck [21] and others have pointed out, if Hayes' reading of this recommendation were applied uniformly, most of the scientific literature would have to be retracted. It is the nature of research results that they are inconclusive.…”

A challenge to scientific integrity: a critique of the critics of the GMO rat study conducted by Gilles-Eric Séralini et al. (2012)

“…Heinemann [4] defended Seralini et al's paper long before it was retracted, and Meyer and Hillbeck [7] demonstrated how the criticism by the European Food Safety Authority (EFSA) suffered from double standards. Following these, I question here whether there exists sufficient substantive evidence given by critics (other than EFSA) to deny the validity of Seralini et al's findings.…”