Background And Historical Significance Society and Risk Analysis

Risk analysis is continuously evolving to address the concerns of society. The next three sections present a short discussion of key concerns for risk analysis of interest to society. The structure of managerial frameworks of risk analysis has an effect on society because it influences how effectively risk is managed. Discussion is provided of various managerial structures and their impacts on risk communication processes.

Society and risk assessment Prediction of risk and attendant uncertainty is not a simple process. In constructing risk assessment models, assumptions

TABLE 3.3. FAO/WHO Principles of Risk Communication (Joint FAO/WHO Consultation, February, 1998, Rome, Italy)

1. Know the audience.

2. Involve the scientific experts.

3. Establish expertise in communication.

4. Be a credible source of information.

5. Share responsibility.

6. Differentiate between science and value judgement.

7. Assure transparency.

8. Put the risk in perspective.

about the underlying mechanisms or processes and formal statistical inferences from available data are made. These assumptions and inferences from limited data may be very subjective judgments that can become points of dispute and controversy for other risk analysts and stakeholders.

For the risk assessment to be used effectively to support decision making about risk management strategies, the risk manager and the stakeholders must understand the risk assessment. An understanding of the risk assessment involves familiarity with: 1) the simplifying assumptions used in constructing the models; 2) whether or not the particular models used are based on consensus of the scientific community; 3) the magnitude of the uncertainty associated with the data and the models; and 4) the procedures for estimation of the likelihood of the occurrence of adverse events for given scenarios. If clear, complete explanations of the assumptions and methodology are provided so that the analysis could be repeated, then the risk assessment is called "transparent." However, one could say that transparency is in the eye of the beholder, because risk assessors must tailor different levels of technical detail for transparency to various audiences of stakeholders and risk analysis professionals.

Besides estimating the magnitude of the risk and the uncertainty of the risk estimates in a transparent fashion, another desirable aspect of a risk assessment framework includes generality. The models must describe processes in a manner that permits application to a wide range of scenarios, for example, depicting a variety of current farm-to-fork food production processes. However, a model may also be too general, requiring many unsupported assumptions or unwarranted inferences and leading to inaccurate estimates of risk. In contrast, the data and the underlying scientific theory may permit useful estimates of risks for only a small specific set of scenarios.

The underlying tension between these two poles of generality and specificity should be addressed in the preliminary phase of risk assessment. This tension can also be addressed in the risk assessment by conducting sensitivity analysis. Sensitivity analysis reveals the effect of changes in model parameters on the estimates of risk. If values of a parameter have high impact on the estimate of the risk (high sensitivity), and the actual value of the parameter is not known accurately, then the uncertainty of the risk assessment results will be great. A thorough analysis of the uncertainty of estimates and the effect of alternative models derived from different assumptions would permit evaluation of more general scenarios, while providing protection against unwarranted conclusions.

Each risk assessment can be thought of as unique. Therefore, a unique combination of procedures appropriate for that risk assessment needs to be developed by the risk assessor. For example, some of the methodologies appropriate for engineering applications, such as fault tree analysis, lack the flexibility to account for dynamic growth that is necessary for modeling risk of adverse consequences from many microbial hazards. Because risk assessments are unique, the Codex Committee on Food Hygiene (CCFH) does not specify methodologies in its principles and guidelines document for microbiological hazards (Table 3.1). For example, the NRC framework (1983) discussed later in this chapter is applicable to microbial hazards, although the methodologies to account for dynamic growth of pathogens in exposure models were probably not anticipated during formulation of the framework for carcinogenic risk assessment.

For a society, the goal of risk assessment is to model realistically the probabilities of consequences, with attendant uncertainties, for given scenarios and not to develop "conservative" estimates of the probabilities of consequences. A model should separate for the risk manager and stakeholders "true" variability (irreducible heterogeneity among hosts, pathogens, or environmental matrix) from uncertainty (ignorance reducible by new research data) imposed by the data and the assumptions of the models. The imposition of conservatism throughout a risk assessment model is not good practice, because bias that may be difficult to quantify is imposed on the risk estimate. Conservatism should be the judgment of the risk management process or of the society, informed by the risk assessment that provides a range of possibilities rather than a worst case.

Society and risk management The concerns and influence of a society on risk management might be inferred from the history of legislation passed by elected and appointed representatives and enforced by governmental regulators. Table 3.4 lists some key legislation that influenced food safety and risk assessment in the United States. Of particular note for this chapter is the

TABLE 3.4. Some Legislative History for Food Safety and Environmental Risk Assessment (ENVIRON, 1988; Cohrssen and Covello, 1989; Code of Federal Regulations, Title 9, volume 2, Chapter III, USDA/FSIS Statutory Requirements)

1. Clean Air Act (1970, amended 1974, 1977, 1990, 1997)

2. Clean Water Act; Safe Drinking Water Act (1972, amended 1974, 1977, 1978; 1997)

3. Comprehensive Environmental Response, Compensation, and Liability Act; Superfund Amendments and Reauthorization Act (1981; 1986)

4. Egg Products Inspection Act (1970; 84 Stat. 1620, 21 U.S.C. 1031 et seq.)

5. Federal Crop Insurance Reform and Department of Agriculture Reorganization Act of 1994 (Pub. L. 103-354; 7 U.S.. 2204e)

6. Federal Food, Drug, and Cosmetic Act (1938, 52 Stat. 1040, amended 1958. 1960, 1962, 1968; amended 1996, 1998 as Food Quality Protection Act (21 U.S.C. 301 et seq))

7. Federal Insecticide. Fungicide, and Rodenticide Act (1948, amended 1972, 1975, 1978; amended 1996, 1998 as Food Quality Protection Act)

8. Federal Meat Inspection Act (1907, 34 Stat. 1260, amended by Wholesome Meat Act, 81 Stat. 584 (21 U.S.C. 601 et seq.))

9. Pathogen Reduction/HACCP Rule (1996, 61 FR 38868)

10. Poultry Products Inspection Act (1957; 71 Stat. 441, as amended by Wholesome Poultry Products Act, 82 Stat. 791 (21 U.S.C. 451 et seq.))

11. President's Food Safety Initiative (1997)

Delaney Clause of 1958 (Table 3.4. item 6), which imposed a zero-risk cancer standard designed to prohibit food additives including pesticides with carcinogenic potential from concentrating in processed foods. A zero-risk standard does not require quantitative risk assessment, but rather a simple statistical test at some prescribed level for the presence of a carcinogen hazard in a processed food.

The changing climate of risk analysis over the past 40 years is evidenced by two recent pieces of legislation that imply or explicitly require risk assessments for food safety under certain conditions. The Federal Crop Insurance Reform and Department of Agriculture Reorganization Act of 1994 established the Office of Risk Assessment and Cost-Benefit Analysis to review the risk assessments and cost-benefit analyses that are used in support of major regulations in the U.S. Department of Agriculture (USDA). The Food Quality Protection Act of 1996, with amendment in 1998, modified the Delaney Clause relating to pesticides and changed the language from "zero risk" to "reasonable certainty that no harm will result from aggregate exposure to pesticide residue." Thus, "safe" food, with respect to pesticides, is not implied by a lack of statistically significant demonstration for the presence of a carcinogenic hazard. Rather, "safe" food is implied by estimates of "reasonable" dietary risk and consideration of sensitive subpopulations.

Society and risk communication In the past, risk assessors may not have considered that risk communication was their responsibility at all, except for communicating with the risk manager. Public meetings might have been convened to announce the results of the risk assessment or to explain the policy decisions that were drawn from an assessment. The attitudes projected by more recent work of the NRC (1996) and the President's Commission on Risk Management (1996) point the way to opening risk analysis to more interactive dialogue throughout the process. Thus U.S. federal agencies (EPA, USD A, and FDA) arc more commonly convening public meetings to introduce risk assessment teams and to solicit data at the start of major risk assessments rather than at the end of the assessments.

10 Ways To Fight Off Cancer

10 Ways To Fight Off Cancer

Learning About 10 Ways Fight Off Cancer Can Have Amazing Benefits For Your Life The Best Tips On How To Keep This Killer At Bay Discovering that you or a loved one has cancer can be utterly terrifying. All the same, once you comprehend the causes of cancer and learn how to reverse those causes, you or your loved one may have more than a fighting chance of beating out cancer.

Get My Free Ebook

Post a comment