Position Statement on Genetically Modified Organisms in the Environment - updated 15 October 2003


  1. The development of genetically modified organisms (GMOs)BN1 is more than a greatly accelerated form of microbial, plant or animal breeding. It can effectively create novel life forms by transferring genes from one species into another species, including animal genes into plantsBN2. GM technology has given breeders the potential to effect these changes at rates unparalleled in the Earth's history. Conventional breeding also produces new strains of organism, some of which may affect native wildlife. However, the use of transgenic techniques, incorporating new combinations of genes into crops and other commercially valuable organisms, may pose additional and different risks to our natural heritage due to potential impacts on ecological systems. There is also potential for GMOs to enable changes in agricultural, forestry and fisheries management, which could be either beneficial or detrimental to wildlife.
  2. Biodiversity has resulted from four billion years of evolution. The UK has international obligations to safeguard its native biodiversity, in particular through the EU Habitats Directive, the EU Birds Directive, and the Convention for Biological Diversity. In the UK, much of our biodiversity is closely associated with agricultural systems and activity, and with managed forests and aquatic habitats. The biodiversity associated with agricultural systems is already being affected significantly by intensification, with many species of farmland birds, butterflies and plants having declined very substantially over the past 50 yearsBN3.
  3. Using certain types of GM crops has the potential to reduce biodiversity further by increasing such intensification. There are also potential risks to biodiversity arising from gene flow and toxicity from some GM crops. However, the JNCC recognises that the use of some GM crops may have potential benefits for farmland wildlife, especially if their use results in management practices having a reduced impact on the environmentBN4. The JNCC believes there should be careful assessment of the implications for biodiversity, and for the environment generally, before decisions are made on the commercial release of genetically modified organisms (GMOs).
  4. This position statement represents the combined views of the three British statutory nature conservation agencies of which JNCC is a joint committee. The agencies are statutory consultees in the process by which applications for release of GMOs into the environment are considered, and also have a general duty to advise government on conservation policies. We are solely concerned with potential impacts of GMO releases on the living environment and on sustainable use of our natural resources, including protected sites and the wider countryside. We have no locus on matters of public health and safety. The agencies, working through the JNCC, advocate using the precautionary principle where commercial releases are proposed, and consider that the release and use of a specific GMO is appropriate only when all of the following criteria are satisfied:



  1. Risk assessment and public consultation
  2. Rigorous environmental risk analysis is undertaken for potential releases of the GMO, including where appropriate analysis of the risks to biodiversity of changes in husbandry, agricultural practices, soil processes and other land and water use, which may result from the adoption of GM technology.
  3. Risks to native biodiversity are shown by comprehensive analysis of evidence to be acceptably low. Direct risks from GMOs may include toxicity of transgenic organisms to wildlife, competitive displacement of native species by transgenic organisms or hybrids with wild species, and effects on soil and aquatic ecosystems. Indirect risks include changes in land and water use and management that are detrimental to the wildlife that use farmland, woodland, freshwater or the seas.
  4. It is demonstrated that GM crops and trees developed to be resistant to insect, bacterial and fungal attack will not have significant adverse effects on native species, including beneficial insects, which rely upon such organisms within food webs, in comparison to the impacts of current systems of agriculture and forestryBN5.
  5. There are adequate safeguards against gene flow between the GMO and native organisms where transgenes are likely to affect fitness, decrease genetic diversity or increase toxicity. The preferred method should be to avoid releasing transgenic organisms with sexually compatible wild relatives in the UK. Applicants wishing to release transgenic native species into the environment should consider incorporating genetic isolation mechanisms into the genomes of the GMOs themselvesBN6. Best practice techniques (such as those described by the Advisory Committee on Releases to the Environment (ACRE) in its report Guidance on Best Practice in the Design of Genetically Modified Crops) should be used in the construction of transgenic organisms.
  6. It can be satisfactorily demonstrated that deliberate or unintentional crossing of the GMO with other GM products that are present in the UK environment will not lead to 'stacked-gene' organisms with increased fitness or capacity to cause harm to non-target species. We do not consider that voluntary codes of practice alone will be able to prevent transgene stacking occurring in crops or wild relatives, so risk assessments for commercial releases of transgenic outcrossing species should consider stacking to be inevitable.
  7. Effective public consultations, appropriate to the nature and scale of the release, are undertaken within a timetable that is reasonable.
    Land use
  8. The use of GMOs should not promote agricultural or forestry intensification on land of nature conservation valueBN7 and should not inhibit the widespread continuation or adoption of more environmentally sustainable methods of agriculture, forestry and fisheries.
  9. Crops engineered to express industrial or pharmaceutical compounds, that are able to outcross with food crops or wild plants in the UK, should not be grown in open fields unless and until it is demonstrated that they will not have adverse impacts on the environment. Incorporating genetic isolation mechanisms may be a method of limiting the risks to the environment if such mechanisms can be demonstrated to be reliable. Otherwise such crops should be grown in containment. We believe that the environmental effects of artificially constructed genes will be even harder to predict than those that occur naturallyBN8.
  10. Reliable mechanisms are set up to enable coexistence between different types of farming systems, including GM, 'conventional' and organic systems, in advance of the commercial growing of GM cropsBN9. Coexistence mechanisms should not prejudice the ability of farmers to manage their land for the benefit of biodiversity or natural resources, for example by requiring increased use of herbicides to control volunteers or by reducing farmers' choice of rotations, management practices or entry into agri-environment schemes.
  11. Effective legislation is put in place to minimise the occurrence of adventitious GM material in both non-GM and GM seed. Thresholds should be set at the minimum detectable level and regularly revised to reflect improvements in analytical technologies. Regulation of adventitious presence should be based on minimising risks to the environment and not solely on food labelling standards.
  12. Legislation is put in place to establish liability for environmental harm caused by the deliberate release of GMOs.
    Monitoring and Clean up
  13. Weed and pest resistance are monitored in areas where crops tolerant to herbicides and insects are grown, and strategies to manage the development of resistance are implemented and enforced.
  14. Plans and resources have been put in place to ensure there is adequate monitoring of the use and possible spread of GMOs in the environment following their commercial and experimental release, with specific work to detect effects on different habitats and species, fulfilling the requirements of Directive 2001/18/EC. This will require a publicly accessible database containing accurate information on the location of all GMO releases that will enable any environmental changes identified in general surveillance and monitoring work to be analysed for possible correlation.
  15. In environmental clean-up work, GMOs are only used where there is a demonstrable advantage over conventional methods. All clean-up techniques are less desirable than pollution preventionBN10.


  1. The JNCC considers that future research and development effort on GMOs must ensure that there is adequate regulation of commercially-orientated and experimental releases into the environment, and that detrimental effects of releases on wildlife are properly assessed. We will therefore:
    1. Continue to provide objective advice both to Government and to industry over potential effects of the release of GMOs on terrestrial and aquatic wildlife. The statutory agencies will continue to act as assessors to ACRE.
    2. Continue to press for changes in the regulatory system to take account of, and minimise, potential ecological effects when assessing the risks of releasing GMOs.
    3. Continue to press for more research on the impact and extent of gene flow from GMOs to native terrestrial and aquatic species, and also on the ecological effects (including those in the soil) of crop management changes resulting from the use of GMOs.
    4. Recognise the need for field-scale studies on the effects on biodiversity of growing GM crops that require or enable changes in management practices, compared to other types of agriculture – for example, herbicide-tolerant and insect-resistant crops.
    5. Continue to urge Government and industry to ensure that there is effective monitoring of possible ecological effects from GMO releases.
    6. Continue to recommend that commercial releases of GMOs, including herbicide-tolerant and insect-resistant crops, are not undertaken until sufficient research has been completed and evaluated, appropriate risk assessments have been carried out to provide public assurance that risks to the environment are acceptably small, and appropriate public consultation has taken place.
    7. Press for the development of legislation to set and enforce standards of seed purity that ensure adequate protection of the environment, and to establish reliable and practicable coexistence measures and clear lines of liability for environmental harm caused by GMO releases.
    8. Continue to advise Government on the impact on biodiversity of international agreements relating to trade and global environmental issues, especially those agreements involving GMOs.

Annex A. Background Notes

The term "genetically modified organisms" for the purpose of this position statement includes a wide range of transgenic (GM) crops, trees, insects, fish, livestock and microorganisms that are currently under development and either have been or could be released into the environment within the foreseeable future.
Genetic (transgenic) engineering is a more radical form of plant and animal breeding, by which genes from other species (or even phyla) can be inserted into the recipient genome. These genes have never been, and in many cases could never naturally be, part of the recipient species' gene pool. Due to the often subtle nature of interactions between transgenes and native genes, it is impossible to predict accurately their behaviour if they should out-cross to native species without carrying out detailed studies of fitness parameters in a range of environments. It is likely that some genes are inherently more risky than others. For example, genes conferring resistance to insects, viruses and fungi in GM crops such as oilseed rape, if transferred to native species, have the potential to increase fitness of the resulting hybrids. These could then become ecological weeds, with the potential to invade native ecosystems and cause adverse impacts on biodiversity.
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Recent research and survey has revealed severe declines in UK farmland bird populations, especially in those species associated with lowland arable and mixed farmland. Because of these declines, farmland bird populations have been included as one of the Government's 'Quality of Life Counts' headline indicators of sustainable development. Long-term research in southern England has identified increased pesticide efficacy as a major factor contributing to declines of skylarks, partridges and corn buntings. Herbicide efficacy is very important in determining the breeding success of these species; low breeding success is strongly associated with highly efficient weed control programmes. One of the factors involved in this effect is the reduction in invertebrate density caused by lack of weeds in arable fields. It has been demonstrated that bird chicks fail to thrive when invertebrate densities are low.
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There is little doubt that biotechnology has great potential to be able to alleviate some of the problems associated with conventional intensive agriculture, especially if out-crossing from GM crops to native species can be prevented. Reductions in, or even elimination of, pesticides by using pest- and disease-resistant varieties, coupled with the prospect of nitrogen fixation and perennial crops, are attractive goals for genetic engineering. They could contribute towards more sustainable agriculture, as long as there were no reductions in biodiversity by diminishing invertebrate food sources, or through toxin transfer through the food chain. Present trends in GM crop engineering are, however, in the opposite direction, with herbicide tolerance being widely used to increase herbicide efficacy, exacerbating the adverse effects of agricultural intensification.
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Pest and disease resistances are currently being engineered into a wide range of crops, although none are currently close to commercial growing in the UK. Insect resistance has been achieved mainly by expressing various types of toxic proteins (for example, Bt proteins and lectins) into GM plants. Although some instances of toxicity to non-target invertebrates have been demonstrated in the laboratory, the limited amount of fieldwork that has been carried out so far (mainly in the USA) suggests that these impacts are not translated into significant population-level effects when compared to using pesticides on conventionally grown crops. Pest- and disease-resistant crops could also have effects on soil ecosystems, which are extraordinarily complex and difficult to study. We recommend further research in this area.
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Recent research has shown that gene flow from some GM crops to native plants and to non-GM crops is inevitable, but there is little research on the impact of such crossbreeding on the genetic fitness of any resulting hybrids. Risks associated with gene flow can be minimised in experimental plots, but may increase if GM crops are grown commercially. The JNCC is especially concerned about the transfer of insect, fungal and viral resistance to native plant populations, causing possible disruption to the population dynamics of the plants themselves and their parasites and predators. However, transgenes that increase fitness of crops or wild relatives in agricultural environments may also pose risks to biodiversity. For example, the presence of one or more herbicide tolerance genes in volunteer oilseed rape plants could cause farmers to instigate changes in weed management that have an adverse impact on arable plant communities in crops and field margins. The technology for preventing gene transfer (by male sterility, pollen incompatibility and changing flowering times) already exists, but has not yet been incorporated into commercially available GM crops. The ACRE report on best practice in the design of GM crops outlines these technologies in more detail. Any adverse impacts resulting from gene flow from transgenic animals, such as fish and insects, into wild populations might be especially difficult to control or reverse, since these species are highly mobile. Technologies for producing sterile transgenic fish are already commercially available, but none of these are currently 100 per cent reliable. It may be hard to predict the impacts of transgenes on fitness of wild animals without conducting experiments in the open environment, especially since transgenes may affect animal behaviour in complex ways. Important uncertainties about rates and patterns of gene flow, and the practical difficulties of preventing escape of transgenic animals, may make it hard to construct valid risk assessments for such deliberate experimental releases.
Besides the need to demonstrate that any changes in land use and management associated with the use of individual GMOs are at least benign and preferably beneficial to wildlife, there is a need for strategic thinking within government as a whole about the likely impacts of biotechnology on agricultural sustainability in the UK and worldwide. We value the continuing role of the Agriculture and Environment Biotechnology Commission in promoting strategic thinking and debate on these issues.
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Constructing 'designer' genes is now routine in medical biotechnology and may be an attractive option for the farming industry when more advanced GM crops are formulated. There is already considerable interest and research into inserting genes coding for industrial raw materials, pharmaceuticals and nutrient supplements ('nutraceutical' crops) into various crop plants, some of which are capable of out-crossing to native species. We believe that this could have serious effects on ecosystems if such genes were to become incorporated into native plants.
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If coexistence between GM cropping and other farming systems is possible, mechanisms are likely to differ between crop species. These may include management practices and/or the use of genetically isolated varieties. Management practices could include minimum separation distances, rotations, volunteer control and cleaning of machinery. The JNCC believes that management practices alone are unlikely to be sufficient to ensure long-lasting coexistence for UK crops that have high rates of outcrossing and/or sexually compatible wild relatives – for example, oilseed rape, sugar beet and fodder beet. The JNCC is also concerned that some changes in farming practices designed to enable coexistence could harm non-crop biodiversity in and around fields.
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Genetically modified bacteria and fungi are already being used experimentally to deal with oil spills and heavy metal contamination. There is considerable potential in extending this to other types of bioremediation, dealing with other types of pollution and contamination. Even if the risks to biodiversity from such GMOs are demonstrated to be relatively low, we are concerned that the existence of these GMOs should not reduce pressure to prevent pollution.