europa    seventh

In the context of the ongoing debate on the risk assessment of GM food/feed in Europe, it is crucial to put the findings of the 2-year feeding study in a perspective that covers:

  1. The scientific quality of chronic toxicity and carcinogenicity testing in rats to whole foods/feeds.
  2. The scientific value of long-term feeding trials for GM food/feed risk assessment.


The evaluation of the scientific value will be conducted in a carefully designed and transparent step-by-step approach.


Criteria to evaluate the scientific quality of 2-year feeding trials will be developed and applied prior to the actual feeding trials. The scientific value will mainly be evaluated by clarifying what toxicity relevant information from risk assessment would trigger a long-term feeding study. In both cases G-TwYST will draw on the experience and standards in other toxicity assessment contexts.

Evaluation of the scientific quality of long-term GM food/feed feeding trials

In order to identify criteria to evaluate the scientific quality of long-term feeding studies, guidance documents for aspects of toxicity assessment relevant to the scope of the WP have been identified and analyzed. The criteria cover all aspects of the feeding trials.

Based on these documents a draft set of suitable criteria has been established by the project team and will be applied to the feeding trials being performed by the G-TwYST project and by the GRACE project as well as to the feeding trials having been performed by other research groups/consortia in the past.
The criteria as well as the experience and insights gained from their application for GM food/feed testing have been discussed in a mini-workshop to which external experts were invited. Subsequently, the draft list of criteria has been revised according to the recommendations resulting from the workshop and a final set of quality criteria has been published at the reports pages of the project website.


Justification of long-term feeding trials for GM food/feed risk assessment

In order to define the triggers that would justify performing a chronic toxicity/carcinogenicity feeding trial, the scientific literature and guidance documents on 90-day feeding trials from a broad range of toxicity assessment contexts will be searched and collected from publicly accessible databases (scientific literature, research projects, data collections, and bibliographies) and further accessible sources such as the GRACE central access database.
Previously applied or suggested trigger items will be subjected to a review by the project team and candidate trigger items will be identified. In a subsequent step the usefulness of the candidate triggers will be evaluated by analyzing the data obtained by the Project with GM maize NK603 and GM maize MON8 10 in 90-day, the 12-month feeding trials, and the preliminary results of the 2-year feeding trials as well as the results of feeding trials having been performed by other research groups/consortia in the past, thereby allowing to determine the added value of long-term feeding trials for GM food/feed risk assessment.
The candidate trigger items and the experience in applying them in practice will be discussed and recommendations will be compiled in a second mini-workshop, to which external experts will be invited (M26, month 43). Based on the results of this workshop a report characterizing the proposed trigger items and describing the underlying rationale will be prepared and published at the project website.

Latest news

Go to news >

Comments on statistical methods for safety assessment published

March 6, 2018


In safety assessments a large number of non-target effects  has to be analysed statistically. A recent paper published in the Journal of Agricultural and Food Chemistry advocates an approach which leads to over-optimistic conclusions. In a recent Correspondence to this journal the concerns about the misapplication of methodology are explained. See: Safety Assessments and Multiplicity Adjustment: Comments on a Recent Paper, available on the Journal of Agricultural and Food Chemistry website at http://pubs.acs.org/doi/abs/10.1021/acs.jafc.7b03686.

Registration for Final Conference open

1 March, 2018


On April 16, 2018 G-TwYST organises a conference on general conclusions and recommendations from three scientific projects: G-TwYST, GRACE and GMO90+. Registration for this conference is compulsory and can be done by completing the registration form at the G-TwYST website. Registration is open until April 6, 2018.

More information, including a preliminary programme, is available on the G-TwYST Final Conference webpage.