This chapter focuses on the importance of problem formulation (PF) in the environmental risk assessment process, which involves the identification of the possible hazards associated with a stressor, i.e. transgenic RNAi expressing plants or RNAi-based pesticides. The risk hypotheses developed from the PF that can be used to hypothesize pathways to risk and support the design of experimental studies to determine environmental impacts are also discussed.

This book contains a series of chapters reviewing the current scientific knowledge on RNAi, methods for developing RNAi systems in transgenic plants and a range of applications for crop improvement, crop production and crop protection. Some chapters examine both endogenous systems in transgenic plants and exogenous systems where interfering RNAs are applied to target plants, pests and pathogens. The biosafety of these different systems is examined and methods for risk assessment for food, feed and environmental safety are discussed. Finally, aspects of the regulation of technologies exploiting RNAi and the socioeconomic impacts of RNAi technologies are discussed.