GM Crop Farm-Scale Evaluations:
Background Papers
The Farm-Scale Evaluations of Genetically Modified Herbicide Tolerant
Crops
Paper for February 2001 AEBC Meeting
A Paper by the Biotechnology Safety Unit, Department of the Environment, Transport and the Regions
The farm-scale evaluations are a three year programme of ecological studies into the effects on the abundance and diversity of farmland wildlife, associated with genetically modified herbicide tolerant (GMHT) crops managed with their companion herbicide as compared with equivalent non-GM crops.
The farm-scale evaluations were announced in autumn 1998 as part of the Government's initiative to strengthen and co-ordinate the assessment and control of GM crops. This comprised:
- A voluntary agreement between Government and the industry body, SCIMAC,
- for a programme of farm-scale evaluations of GMHT crops; and
- no general unrestricted cultivation of GM crops in the UK until the farm-scale evaluations are complete;
- The setting up of a subgroup of the Advisory Committee on Releases to the Environment (ACRE) to consider the wider biodiversity implications of the introduction into agriculture of GM crops and make recommendations on how such impacts should be assessed and controlled;
- Review of the controls on pesticides with respect to their use on GM crops.
These actions were taken in response to concerns originally raised by ACRE and at the National Biotechnology Conference in 1997 and subsequently by English Nature and concerned non-Governmental Organisations (NGO).
The crops in the FSE either have or are very close to obtaining approval for general cultivation throughout EU under Directive 90/220 on the release of genetically modified organisms into the environment. The GM crops are oil seed rape and maize tolerant to the broad-spectrum herbicide glufosinate ammonium, Libertyâ, and sugar and fodder beet tolerant to glyphosate, Roundupâ.
The European Regulatory Authorities and their scientific advisers had assessed the risks to the environment and human health for compliance with the requirements of the directive but questions remained about the impact of the new herbicide regime on the abundance and diversity of farmland wildlife. The farm-scale evaluations were therefore set up to address this specific remaining area of uncertainty.
The Government acted to ensure that these crops would not be introduced into commercial agriculture until it was satisfied that this would not give rise to an unacceptable impact on the environment.
Mr Meacher's statement in 1998 and the specification for the research contract make clear that the farm-scale evaluations are investigating the effects of the management of the crops with the relevant herbicide not GM crops themselves. However, the Government is taking the opportunity to monitor the growing crops and our understanding of pollen flow. In the maize and rape fields the dispersal of pollen and resulting cross-pollination events in the non-GM half of the field and nearby sexually compatible crops is being monitored and in the case of rape, cross-pollination with wild relatives is monitored.
Other concerns have been raised about the safety of GM crops such as the stability of genetic modification, horizontal gene transfer, antibiotic resistance markers, viral vector promoters. As they have arisen, these issues have been referred to ACRE for advice. In 1999 ACRE published a comprehensive review of the risk assessment for the first herbicide oilseed rape to receive EU approval (from PGS now Aventis). They are currently reviewing the dossier and concerns raised about the GMHT maize which already has EU-wide (Part C) approval (Aventis T25 maize). They have also given specific advice on the safety of the 35S promoter and horizontal gene transfer.
Decisions and procedures at the end of the FSE
The field work on the spring sown crops is due to end in autumn 2002 and that on the autumn sown rape in summer 2003. The results of the ecological studies will be collated and analysed by the research consortium against the null hypothesis that there are no significant differences between the biodiversity associated with the management of the particular GMHT crop and the comparable non-GM crop at the farm scale. The hypothesis will be tested separately for each indicator. The data will reveal whether or not there are any statistically significant differences in the abundance and diversity of the indicator species between the two cropping regimes. The results and statistical analysis will be presented for scrutiny by the independent Scientific Steering Committee overseeing the evaluations. When they are content the work will be published in peer reviewed scientific journals. The raw data will also be made available for study.
Ministers are likely to wish to refer the results to ACRE and the Advisory Committee on Pesticides (who have to approve the herbicide for use with the crops involved) for advice. ACRE might then conduct a public consultation exercise as part of its evaluation of the results. Both advisory committees will then advise Ministers, the National Assembly in respect of Wales and the Scottish Executive for Scotland. In the light of this advice Ministers would then make a joint decision on the future commercialisation of each of the GMHT crops involved in the FSEs. This would also depend on whether decisions had been taken by member states on consent under Part C of directive 90/220 and the other approvals necessary for commercial growing, such as seed listing, were in place.
Separation Distances
The GMHT crops in the farm-scale evaluations have been assessed for their impact on the environment and safety for human health through the Directive 90/220 process. The Advisory Committee on Novel Foods and Processes and the Advisory Committee on Animal Feeds have advised, through ACRE, that the crops in the FSE do not pose a risk to health if eaten by humans or animals. Similarly, any seeds or plants arising from cross-pollination with conventional crops do not pose a risk to health if eaten. ACRE has advised that the presence of these GM plants in fields does not pose a risk to the environment. Therefore, there is no need on safety grounds for separation distances between the GM crops and other crops, or other features in the environment.
Separation distances are used to deliver product integrity. The industry body, SCIMAC, working with MAFF, has developed a code of practice and guidance for farmers on the growing and management of GMHT crops. This is designed to safeguard the GM crop and nearby conventional crops by the use of good agricultural management, separation distances and volunteer control. The level of interaction and resulting presence of GM traits in conventional crops is a matter for ongoing discussion between all interested parties. It will need to be resolved if GM crops are to enter commercial agriculture in the UK.
With respect to the GM crops in the farm-scale evaluations, the separation distances being used will ensure that a very small amount of GM material arising from cross-pollination with conventional crops, if any, will enter the UK food and feed chain.
Page published 20 February
2001;
Page last modified
10 August, 2002