three workshops to seek input from the public. A critical early challenge was to refine the charge. The committee defined the future of agriculture to be the next 10–20 years. Beyond 20 years, it was felt that predicting technological innovations and their effects is extremely difficult. For example, it would have been extremely prescient for someone to predict in 1979 that within 20 years transgenic varieties would constitute upwards of 25% of all planted acreage of some crops. A 20-year span apparently is also sufficient for adverse unexpected effects of technology to manifest themselves. In the case, for example, of the chlorinated hydrocarbons, widespread use beginning in the early 1950s culminated in regulatory restrictions in the early 1970s (Chapter 2).
The committee also felt that the term pesticide required a more precise definition for the purpose of its report. The legal definition, set forth in the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), is in part inconsistent with biological definitions of pesticides. The definition also has social aspects; public perceptions color related policy discussions and decisions (Chapter 2). Accordingly, the committee took a broad view of pesticide, including the strict legal definition, but also including microbial pesticides, plant metabolites, and agents used in veterinary medicine to control insect and nematode pests (Chapter 2).
With respect to the first charge—to identify circumstances in which chemical pesticides will continue to be needed in pest management—the committee decided early during its deliberations that an assessment of the full range of agricultural pests and of the composition and deployment of chemical pesticides to control pests in various environments would be an impossible task because of the large volume of data and the number of analyses required to generate a credible evaluation. The committee reviewed the literature and received expert testimony on the potential effects of pesticides on productivity, environment, and human health (Chapter 2) and on the potential to reduce overall risks by improving IPM approaches that use chemicals under diverse conditions—soils, crops, climates, and farm-management practices. The committee concluded that uses and potential effects of chemical pesticides and alternatives to improve pest management vary considerably among ecosystems. That conclusion was reinforced by expanded solicitation of expert opinion (Chapter 5). Overall, the committee concluded that chemical pesticides will continue to play a role in pest management for the foreseeable future, in part because environmental compatibility of products is increasing —particularly with the growing proportion of reduced-risk pesticides being registered with the Environmental Protection Agency (EPA) ( Chapter 4), and in part because competitive alternatives are not universally available. In many situations, the benefits of pesticide use are high relative to risks or there are no practical alternatives.