Regulatory Industrial And International Implications

Risk assessment, as described in the introduction of this chapter, is a structured, systematic process linking sound scientific research and policy. The outputs of a risk assessment, predictions for given scenarios of the risk of an adverse event with attendant uncertainty, would inform the risk manager, who has the responsibility of devising risk management strategies. One possible strategy for government risk managers is imposing regulations that require certain criteria or standards to be met. The justification for establishing stan dards is to protect the public health. However, the risk manager would consider other factors such as a cost-benefit analysis, in addition to the results of the risk assessment, that impact the decision about the appropriate level for standards to protect public health. Actually, setting regulatory standards is a risk management activity, which incorporates the stakeholders in structured dialogue through regulatory rulemaking. As such, the expanded concept of risk characterization has many similarities to regulatory activities. As discussed above, there is movement toward requiring standards defined in regulations to be supported by risk assessments. Assessments can be used to support regulations by comparing a "baseline" risk that exists when there are no regulatory requirements to the expected risk when there is compliance with the regulatory requirements.

As alluded to above, often the information and data necessary to conduct a full risk assessment are not available. However, for a variety of social, ethical, and political reasons, there is a compelling need to act. Thus agencies have defined regulatory standards using an assortment of procedures, including the ones described above, qualitative analysis, safety assessment, worst-case scenarios, and other practices, such as grandfathering prior procedures that appeared "safe" on the basis of experience over a long period of time. A possible consequence of applying these somewhat ad hoc procedures is the imposition of standards for exposure that are not directly linked to demonstrated reductions in public health risk. As food safety decisions become more risk based, risk assessments will replace these ad hoc but perhaps workable and useful procedures. A consequence is that the data, assumptions, and methodology supporting a risk assessment will be more carefully scrutinized. Risk assessment methodology will become more crucial as our society moves away from food systems designed simply to reduce exposure to hazards toward more risk-based systems designed specifically to protect public health.

Food Safety Standards

As part of their regulatory activities, agencies set food safety standards. A food safety standard is a description of a specified amount of product relating, in theoretical probabilistic terms, the distribution of levels of hazardous materials that would provide reasonable certainty of no harm to consumers. For example, in the food microbiology area, a food safety standard would specify, in theoretical probabilistic terms, the distribution of the number of pathogens in a finished food product (USDA, 1999) originating from a hypothetical "worst-case" product. In the chemical area, a food safety standard might specify that a process-average level of a hazard must be less than a specified value.

To determine "safety" standards based on science, one would need to know the dose-response relationships or the highest amount of hazardous agent that could be ingested by different human subpopulations in a given food matrix without adverse outcome. Information on the minimum "apparent infective dose" might be inferred from food microbiology data generated in outbreak investigations of foodborne disease. True "infective dose" is dependent on many factors and is impossible to measure directly in humans and difficult to estimate. One true "infective dose" does not exist for the entire human population. Rather, infective doses depend on humans being in particular situations. In this sense, the infective dose depends on the particular scenario under consideration. For example, the infective doses for healthy adult consumers are expected to differ from the infective doses for the subpopulation of consumers with immune dysfunction or recent antibiotic administration (which reduces the protective effect of the indigenous GI tract microflora). Another example is that dose-response relationships may differ according to food matrix. Because of the enhanced ability of bacteria to survive in fatty matrices, the same doses in fatty foods might result in higher probabilities of illness than those for nonfatty foods. However, in the absence of knowledge about dose-response relationships for given scenarios, the food safety standards are established by some government agencies to reflect conservative estimates of "infective dose" for the hypothetically most susceptible individual based primarily on expert judgment. As more data become available, the standards would be adjusted. For example, the standard with respect to the presence of E. coli 0157:H7 has become stricter because from recent outbreaks, it is thought that this pathogen may be highly virulent, and apparently, small ingested doses could cause illness and even death in susceptible subpopulations.

Risk Assessment and HACCP

Hazard Analysis and Critical Control Point (HACCP) programs are evolving as a risk management strategy in food production, processing, distribution, and preparation systems worldwide. HACCP programs involve the identification of critical control points (CCPs) of a process. A CCP is defined in the Code of Federal Regulations (Title 9, Chapter III, Part 417.1) as "a point, step, or procedure in the food process at which control can be applied, and as a result, a food safety hazard can be prevented, eliminated, or reduced to acceptable levels." The risk manager determines the acceptable level of safety such that consumption of the product is associated with reasonable certainty of no harm (safe or unadulterated). The USDA is embracing HACCP as a regulatory tool in an effort to properly place responsibilities and to provide flexibility in manufacturing procedures (USDA, 1996, 1999). Thus, under HACCP regulations, establishments are required to identify CCPs and establish process "control limits" for them. These "control limits" are used to evaluate the effectiveness of the processing, that is, whether the process is in control so that the product woufd be "safe." In this sense, HACCP appears to be an integration of risk management and process control.

Some similarities exist between the inputs for the first elements of risk assessment (hazard identification) and HACCP (hazard analysis). For example, hazard identification and hazard analysis might both consider data from epidemiological investigations that reveal risk factors, food vehicles, associations with adverse health outcomes, the nature and severity of illness, and effects in sensitive subpopulations.

The result of the hazard analysis is a description of the hazardous agents, their levels, and how they might enter into the product. The goal of processing would be the control of the hazard for the final product, such that the final product would meet a food safety standard defined by governmental regulation. Once this is accomplished, the establishments would identify the CCPs of the process that would control the hazard and result in a product that meets the food safety standard, if the processing at these CCPs were controlled. To determine what "to be in control" means, the establishment needs to determine processing objectives or standards for the CCP and process control procedures for evaluating whether or not the processing objectives are being met.

As discussed above, risk assessment could be used in defining the food safety standard that would be used as an objective for designing an HACCP plan. The standard of "safe" under HACCP, however, may not be risk based. Rather, determining a "safe" product is often a subjective judgment based on historical practices, such as good agricultural or good manufacturing practices. These practices thus may become acceptable for good manufacturing and would be incorporated into the HACCP plan. Alternatively, the judgment of "safe" might be based on use of a "quasi-risk assessment" procedure such as one of those discussed above. A common approach in process design might be that simply reducing exposure is sufficient to provide a "safe" product. This approach might lead one to the opinion that occasional samples containing detectable levels of a hazard do not necessarily indicate that the product is unsafe. The consequence of this somewhat flawed logic could be that manufacturing practices may become acceptable that reduce exposure but still would not provide the lowest-risk product that could be obtained.

Under the HACCP regulatory philosophy, once a food safety standard is defined, establishments would be required to determine their own processing procedures to achieve the food safety standard. In reality, establishments may not be able to design processing procedures that guarantee a "safe" product. Thus, in addition to the requirement of a HACCP plan, U.S. agencies are defining acceptable "process performance" goals for selected control steps (USDA, 1999). The regulatory process performance goals assume only minimal procedural constraints. For example, a process performance goal for a thermal treatment control step would require that the process achieve a theoretical .v — log10 relative reduction of certain pathogens on raw product that has not been temperature abused or has been handled according to some acceptable handling procedures before the control step. In this example, the government is performing a hazard identification and identifying the control step and processing goals for the control step. The process control procedures and control limits for ensuring that the process is achieving the process performance goal are still the responsibility of the establishment. In addition, the agencies provide compliance guidelines to assist the industry to achieve the process performance goal (USDA, 1999).

Risk assessment can illuminate the possible risks that could occur for particular manufacturing processes. However, risk assessments or other quasi-risk assessment procedures that are performed by government agencies usually estimate possible risk that reflects the product of the industry as a whole. We emphasize here that the calculation of risk in this application depends on the processing scenario that describes the handling or the processing of the product before the product reaches the control step and after the product leaves the control step. From such an assessment, a food safety standard and corresponding process performance goal are established for the control step. The process performance goal is defined such that, for some defined scenario, the product produced at the control step from a process satisfying the process performance goal would satisfy the food safety standard and thus be considered "safe." Thus establishments are required to design their processes for the specified control step, cognizant of handling of the product before and after, to satisfy the process performance goal.

However, it might be possible for an establishment to control its process with the use of certifications for incoming material or other means to produce a product that satisfies the food safety standard, even though their process at the specified control step might not meet the regulatory process performance goal. That is, an establishment might be able to more effectively control the process preceding and subsequent to the control step than the level of control assumed by the government for establishing the process performance goal. In addition, an establishment can develop particular knowledge of its product to design processes such that the final product satisfies the food safety standard, even if the process performance goal is not satisfied. Thus, manufacturers may be able to devise alternative process performance goals such that the final product would satisfy the required food safety standard (USDA, 1999).

A risk assessment that accurately models the processes, including storage, thermal, and cooling processes, would provide information to establishments that would help them define CCPs and processing goals for the CCPs. In general, a good risk assessment model would allow establishments to more effectively design processes based on food safety criteria. In fact, a complete risk assessment would provide estimates of risk and attendant uncertainty corresponding to different scenarios of processing, from which CCPs and control limits could be established (Zwietering and Hasting, 1997). The coevolution of risk assessment and HACCP will be crucial to development of risk-based standards that not only reduces exposure but reduces risk.

International Activities

Much attention has focused in the U.S. and in the international arena on definitions, principles, and guidelines for risk assessment (Codex Committee on Food Hygiene, 1998; ICMSF, 1998; McNab, 1998; NACMCF, 1998). Two leading international organizations in global food safety are the World Health Organization (WHO) and the Food and Agriculture Organization (FAO).

Both organizations participate in deliberations of the Codex Alimentarias Commission (CAC). The 163 member countries of the CAC contribute to the work of various committees, such as the Codex Committee on Food Additives and Contaminants (CCFAC) or the Joint FAO/WHO Expert Committee on Food Additives (JECFA), that develop international consensus documents for assessing and managing risk. The scientists convened by JECFA since 1956 have established Acceptable Daily Intakes (ADIs), Provisional Tolerable Weekly Intakes (PTWIs), and other end points for more than 700 chemical hazards in foods (Kaferstein, 1998). JECFA advises the CCFAC on the appropriate level for numerical standards for these chemical hazards. This advice may lead to approval by the CAC of Maximum Residue Limits (MRLs) or Maximum Limits (MLs) as internationally recognized standards for protection of public health (Kaferstein, 1998). The CAC has also adopted guidelines for radioactive hazards in foods (Kaferstein, 1998). The FAO/WHO are also developing an advisory body similar in function to JECFA that would address scientific issues involved in setting standards for microbiological hazards in foods in for international trade.

The U.S. or any other government may choose to impose standards for foods eaten by its consumers more or less protective than those standards approved by Codex (WHO, 1998). Especially where Codex limits do not exist for certain hazards, disputes may arise between countries that trade in a food commodity but impose different standards or levels of protection for their citizens. The World Trade Organization (WTO) is the body that arbitrates such international disputes (WHO, 1998). Article 5 of the Agreement on the Application of Sanitary and Phytosanitary Measures (SPS) states that sanitary measures to protect public health must be supported by a risk assessment that takes "into account risk assessment techniques developed by the relevant international organizations." Thus, on the international level, development of standardized procedures and risk assessment techniques continues to be important.

The Codex Committee on Food Hygiene (CCFH) is developing key documents relating to this issue of international food safety and microbial hazards. Documents have been prepared to address separate frameworks for risk assessment and risk management. The first document on risk assessment, the "Principles and Guidelines for the Conduct of Microbiological Risk Assessment" (CCFH, 1998), was prepared under an expedited process and was finalized less than 3 years after development of the original discussion paper. The principles from this document (CCFH, 1998) are listed in Table 3.1. A second document dealing with risk management principles was prepared from a FAO/ WHO Consultation on Risk Management (1996). The principles from this document (FAO/WHO, 1996) are listed in Table 3.2. At present, a draft document based on the FAO/WHO Consultation on microbiological risk management (1996) is just entering the Codex process (Discussion Paper on Recommendations for the Management of Microbiological Hazards for Foods in International Trade, CX/FH 98/10, www.fao.orgjWAICENTIFAOINFOI ECONOMICjESNjcodexIReports). The structure presented in these three documents seem to us more consistent with the original NRC paradigm from 1983 in that the RC is defined strictly in the domain of risk assessment. Although these documents acknowledge the need for risk communication as part of risk management activity, they do not address in depth the interactive elements of risk analysis (assessment, management, and communication) described by the NRC (1996) and discussed in this chapter. Undoubtedly, future deliberations of the Codex Committees will address the tensions and interactions involved with risk analysis for both microbiological and chemical hazards.

Another recent development reflected in the Codex discussion paper on risk management is the notion of "Food Safety Objective'" (FSO) (ICMSF, 1998) defined in Item as "a statement based on a risk analysis process which expresses the level of hazard in a food that is tolerable in relation to an appropriate level of protection." However, this FSO definition does not represent a consensus position at the time of this writing. Further elaboration of the definition of terms in this definition and corresponding procedures to determine FSOs are needed. As discussed in this chapter, the application of risk analysis for establishing regulations and food safety goals is in its infancy. The openness of the analytical-deliberative process of risk analysis as discussed in this chapter is needed to develop solutions to address global food safety issues.

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