BOX 1.4 Harms, Hazards, and Risks
The charge of the committee was to identify, but not to quantify, risk issues concerning products of animal biotechnology, and to provide criteria for selection of those risk issues considered most important that need to be addressed or managed for the various product categories. In order to provide criteria for selection of risk issues, it is important to understand how risk is determined. As outlined in Chapter 5 and as set forth by NRC (1983; 1996), a hazard: is an act or phenomenon that has the potential to produce harm, and risk is the likelihood of harm resulting from exposure to the hazard. This committee used the NRC (1996) definition of risk to develop a set of working steps to prioritize concerns. Because risk is the product of two probabilities: the probability of exposure, and the conditional probability of harm given exposure has occurred, the steps in risk analysis are to: (1) identify the potential harms, (2) identify the potential hazards that might produce those harms, (3) define what exposure means and the likelihood of exposure and 4) quantify the likelihood of harm given that exposure has occurred. (The committee notes that risk analysis in other fields can and does include additional steps in risk assessment; see Kapuscinski, 2002). Multiplying the resulting probabilities then was used to prioritize risk. While absolute probabilities are difficult to determine at this time, relative rankings from high to low are possible based on available evidence for each category. The risks, harms, and hazards are different for each chapter because the issues are different (i.e., a hazard resulting in an animal wellbeing concern might not be an environmental or human health concern).
Discussion of concerns regarding impacts of GE mice on the environment and human health also are limited in this report for several reasons. GE mice are not part of the animal production system for human food, and laboratory mice are highly unlikely to escape the confines of animal facilities because of their economic value and the generally high-quality care given to laboratory rodents. While mice might be a high risk for escape, might feralize easily, and might carry many different transgenes, the functionality of the transgenes used in mice rarely has been for a construct that will increase fitness in natural environments. Thus, the overall risk for most constructs is expected to be low. If mice were developed to be resistant to pest control measures (pesticides) or to be more disease resistant, then risks would be much higher. However, the use of mice in this way seems quite unlikely.