Consensus Report

Each report is produced by a committee of experts selected by the Academy to address a particular statement of task and is subject to a rigorous, independent peer review; while the reports represent views of the committee, they also are endorsed by the Academy. Learn more on our expert consensus reports.

This book explores the risks and benefits of crops that are genetically modified for pest resistance, the urgency of establishing an appropriate regulatory framework for these products, and the importance of public understanding of the issues. The committee critically reviews federal policies toward transgenic products, the 1986 coordinated framework among the key federal agencies in the field, and rules proposed by the Environmental Protection Agency for regulation of plant pesticides.

Key Messages

  • It is important that the tests that are performed be rigorous, logical, and scientifically sound.
  • Both conventional and transgenic pest-protected crops could have effects on nontarget species, but these potential effects are generally expected to be smaller than the effects of broad-spectrum synthetic insecticides.
  • For some novel pest-protectants developed for future commercialization, longterm toxicity testing may be warranted. Tests which involve feeding of large quantities of pest-protected plants to animals have limitations, and the results can be difficult to interpret.
  • Health impacts that the committee considered fall into three general categories: allergenicity, toxicity, and pleiotropic effects of genetic modifications.
  • Monitoring for pleiotropic changes in plant physiology and biochemistry during the development of pest-protected plants should be an important element of health-safety reviews, in addition to testing the toxicity of the introduced gene products.
  • Pest resistance to pest-protected plants could have a number of potential environmental and health impacts such as a return to the use of more harmful chemicals or replacement of an existing pest-protected variety with novel varieties for which there is less information available about health and environmental impacts.
  • Pollen dispersal can lead to gene flow among cultivated crops and from cultivated crops to wild relatives but that only trace amounts of pollen are typically dispersed further than a few hundred feet.
  • Regulators should be sensitive to the unique issues facing researchers, plant breeders, and seed distributors, particularly those in the public sector or those who have not traditionally been subject to federal regulation.
  • Tests should be conducted whenever possible using the protein as it is expressed in the plant.
  • The committee finds that, operating under the coordinated framework, EPA, USDA, and FDA have successfully applied existing statutes to address the introduction of transgenic pest-protected plant products, but concludes that there is room for improvement.
  • The committee found some areas where the risk assessment process for transgenic pest-protected plants could be improved.
  • The committee found some room for improvement in the procedures used in USDA's review of out-crossing or gene flow for virus-resistant squash.
  • The committee found that the three agencies have common data requirements specifically for biology of the recipient plant, molecular biology methods used to develop the product, identification and characterization of inserted genetic material and its product(s), and identity and characterization of selectable markers.
  • The committee is not aware of any evidence that foods on the market are unsafe to eat as a result of genetic modification.
  • The present committee found the three general principles to be valid within the scope of issues considered by the 1987 paper, and the present report further clarifies and expands on these principles.
  • The transfer of either conventionally bred or transgenic resistance traits to weedy relatives potentially could exacerbate weed9 problems, but such problems have not been observed or adequately studied.
  • The use of conventional pest-protected crops might have the potential to lead to human and animal health impacts.
  • The use of pest-protected crops could lead to greater biodiversity in agroecosystems where they replace the use of those insecticides.
  • There is a need to significantly increase research aimed at assessing the potential risks posed by conventional pest-protected plants, and make improvements of conventional breeding procedures, if found appropriate.
  • There is an urgency to complete the regulatory framework for transgenic pest-protected plant products because of the potential diversity of novel traits that could be introduced by transgenic methods and because of the rapid rate of adoption of and public controversy regarding transgenic crops.
  • When the active ingredient of a transgenic pest-protected plant is a protein and when health effects data are required, both short-term oral toxicity and potential for allergenicity should be tested. Additional categories of health effects testing (such as for carcinogenicity) should not be required unless justified.