EFSA reconfirms previous risk assessment conclusions of Monsanto’s GM maize NK603

Following a request by the European Commission, the European Food Safety Authority (EFSA) assessed the scientific publication by Mesnage et al. (2016), including its relevance for the risk assessment of maize NK603.

In their publication, Mesnage et al. (2016) reported that maize NK603 is substantially non-equivalent to a non-GM maize comparator, and point to unintended changes in maize NK603. Mesnage et al. (2016) analysed the proteomic and metabolomic profiles of maize NK603 kernels and compared those to a non-GM maize line used as a comparator. In addition, the authors quantified the levels of expression of the CP4 EPSPS protein in maize NK603.

The maize kernels used for the -omics analysis were obtained from a field trial with maize NK603 (treated and untreated with glyphosate-containing herbicides) and the non-GM comparator at a single location, not further described in the publication, over two consecutive seasons, without replication per year. Consequently, there is a lack of statistical power for the analysis to demonstrate the significance of the identified differences described in the publication. Moreover, the publication does not provide sufficient information on the genetic similarity between the GM line (DKC 2678 Rounduptolerant NK603) and the non-GM comparator. Uncertainty therefore remains on the similarity between the maize NK603 variety and the non-GM comparator used in the field trial. EFSA considers that there are severe shortcomings in the experimental design, as well as uncertainties on the suitability of the test material as described by Mesnage et al. (2016). Furthermore, the interpretation of the results is incomplete, since the authors did not take into account natural variability of the endpoints analysed. Uncertainty remains with regard to potential contamination of the study materials by pathogens and the related confounding effects on the study results.

In conclusion, the evidence reported by Mesnage et al. (2016) is insufficient to indicate the necessity to revise the risk assessment conclusions on maize NK603. The publication presents no new scientific information that would invalidate the previous EFSA GMO Panel risk assessment conclusions of maize NK603. Therefore, EFSA considers that the previous risk assessment conclusions on maize NK603 remain valid and applicable.