Final results and recommendations of the EU research project GRACE
Experts from 20 countries came together in Potsdam from 9th – 10th November to discuss answers to the following questions:
- What is the added value of 90-day rat feeding trials for the safety assessment of genetically modified plants?
- Can alternative approaches reduce or substitute these animal trials?
- How to increase the scientific rigour of risk/benefit assessment of genetically modified plants?
The need to reconsider the value of rat feeding trials for the safety assessment of genetically modified (GM) plants and the controversial debate about scientific findings on the safety of GM plants were the main drivers for the EU-funded research project GRACE (GMO Risk Assessment and Communication of Evidence).
GRACE picked up the stake by two main work streams:
- Improving the interpretation of 90-day rat feeding trials, clarifying their added value and exploring alternative approaches to reduce or substitute animal trials,
- developing and testing an approach to systematically gather and evaluate the quality of existing evidence on the impact of GM plants.
In doing so GRACE developed and implemented high standards for stakeholder engagement and transparency in all key stages of the project: during planning as well as interpreting of the results. All GRACE data are available for public scrutiny and debate.
(A) Feeding trials:
GRACE scientists did not find any indication that a routine performance of 90-day feeding studies with whole food/feed would provide additional information on the safety of genetically modified (GM) maize MON810 when compared to the compositional comparison of the GM variety and its closest conventional comparator in terms of an initial safety assessment. Moreover, the 90-day feeding trials performed did not reveal any scientific trigger for an extension of the feeding period. Data gathered in the course of an additional 1-year feeding trial are in accordance with the conclusions made in the 90-day trials, i.e. that the feeding of maize MON810 to rats did not lead to adverse effects. Consequently, the 1-year study conducted in GRACE did not provide relevant additional information when compared to the 90-day studies.
The data generated by GRACE showed that non-targeted feeding studies may lead to randomly generated significant differences between animal feds with the GM test material and animal fed with a control diet. Such results are not informative for risk assessment. GRACE data support the scientific reasoning that only in case a trigger is available from the initial molecular, compositional, phenotypic and/or agronomic analyses, feeding trials with whole food/feed may provide an added scientific value for the risk assessment of GM crops. Thus, feeding trials might be considered, provided that the study design can be tailored to the posed safety concern.
Due to these limitations of rat feeding trials with GM whole food/feed, a mandatory performance in the course of GMO risk assessment cannot be justified in the light of the European goal to replace and reduce animal tests.
With respect to alternative studies it was concluded that available methods are very promising but cannot yet replace animal feeding trials in routine GMO risk assessment. In the future, they might help to decide whether an animal feeding trial is necessary and what should be the focus of this feeding study. Two different approaches were tested in the context of GRACE:
- The so called omics approaches may detect unintended compositional differences (proteins, metabolites etc.) of GM crops in comparison with non-GM plants. Thereby omics may contribute to scientifically justify rat feeding trials with whole food/feed and to target the study design to the posed safety concern.
- In vitro studies such as the exposure of GM plant extracts to cell cultures provided promising results but will have to be validated.
(B) Improved methods for evidence synthesis
The project also established new and more comprehensive methods for systematically collecting and assessing existing scientific evidence on environmental, health and socio-economic effects (risks and benefits) of GM plants: systematic reviews and evidence maps. These methods make it possible to draw more robust conclusions on these effects, systematically reflecting the entire body of research available.
In testing these methods for the purpose of GMO risk research and assessment it was for instance confirmed that the conclusions of previous risk assessments on GM insect resistant Bt crops are still valid. Bt maize showed no effects on populations of non-target organisms such as beetles and butterflies or to soil microorganisms compared to conventional maize.
GRACE Final Conference
- 9-10 November 2015 (Potsdam, Germany)
GRACE Stakeholder Workshops on Draft Results, Conclusions and Recommendations
- Use of Evidence Synthesis in GMO Impact Assessment
5-6 October 2015
- Feeding and Alternative Studies on GM Maize
7-8 October 2015