ABSTRACT
Crops genetically engineered to express insecticidal proteins have been used in U.S. agriculture since 1996 and are being increasingly adopted worldwide. The ecological safety of these crops has been extensively considered by regulatory agencies
4.1 Introduction .................................................................................................. 103 4.2 Commercial History of Plant Insecticidal Proteins ...................................... 104 4.3 Framework for Ecological Safety Assessment of Insecticidal Proteins ....... 105 4.4 Regulatory Perspective on Insecticidal Protein Ecological Safety .............. 107 4.5 Problem Formulation: Characterization of the Nature of Insecticidal
Proteins and Their Anticipated Ecological Effects ...................................... 108 4.6 Characterization of Exposure and Effects of Insecticidal Proteins
on Nontarget Species .................................................................................... 110 4.6.1 Lepidopteran-Active Corn: Cry1Ab and Cry1F ................................ 110 4.6.2 Coleopteran-Active Corn: Cry3Bb1 and Cry34Ab1/Cry35Ab1 ........ 113 4.6.3 Lepidopteran-Active Cotton: Cry1Ac ............................................... 116 4.6.4 Lepidopteran-Active Cotton Pyramids: Cry1Ac + Cry2Ab2
and Cry1Ac + Cry1F ......................................................................... 116 4.7 Nontarget Risk Characterization Relevance to Ecological Safety ............... 118 4.8 Insect Resistance Management in Relation to Ecological Safety
of Insecticidal Proteins ................................................................................. 120 4.9 Future Needs and Considerations for Insecticidal Protein Ecological
Safety Evaluations ........................................................................................ 120 References .............................................................................................................. 121
prior to their commercial release, and is confirmed by a growing body of published research and experience under a variety of environments and management regimes. Ecological risk assessment provides a framework to understand the safety of these crops by considering the hazard potential of the expressed proteins in conjunction with environmentally relevant exposure scenarios. The ecological risk assessment framework applied to plant-expressed insecticidal proteins also provides insights into data and assessment requirements for forthcoming transgenic crops.
