There are many hazards associated with food that can and do result in injury and harm to human health. Millions of people worldwide suffer from some sort of "food poisoning" each year. Uncontrolled application of agricultural chemicals, environmental contamination, use of unauthorized additives, microbiological hazards and other abuses of food along the food chain can all contribute to the potential of introducing or failing to reduce hazards related to food. With increased awareness of the effects of food hazards on human health, the increasing importance and rapid growth of world food trade and the demand by consumers for a safe food supply, analysis of the risks associated with food has become more important than ever before.
Consumers have expressed concern about the safety of food additives, agricultural and veterinary chemical residues, biological, chemical and physical contaminants, radionuclide contamination and uncontrolled and unacceptable food handling practices and processing which can result in the introduction of hazards to food at all stages along the food chain, from primary production to the consumer. These concerns have been voiced most often by consumers in the developed world; however, continuous improvements in global communication have heightened the interest of consumers throughout the world on these matters.
The Codex Alimentarius Commission defines a hazard as a biological, chemical or physical agent in, or condition of, food with the potential to cause an adverse health effect. Therefore food hazards can be classified into three categories: physical, chemical or biological. Physical hazards (e.g. stones in rice or beans; bone pieces in meat) are the most easily understood; the impact of chemical and biological hazards on human health is far more difficult to understand because of the complexities of interactions between hazards and human biochemistry and the absence of scientific data to confirm the theories. Human responses to disease or to agents that cause adverse reactions are dependent on a number of variables, many of which are interlinked. In addition, health effects may be severe in one person, mild in another and completely absent in others.
PROCESS OF RISK ANALYSIS
The risk to the world's population from hazards in and on food depends largely on the degree of control exercised by producers, processors and official food control authorities to prevent or minimize the risks to acceptable safe levels. Food safety risk analysis is an emerging discipline, and the methods used for assessing and managing risks associated with food hazards are still being developed.
It is important to recognize the difference between "hazard" and "risk". As stated above, a hazard is a biological, chemical or physical agent in, or condition of, food with the potential to cause harm. In contrast, risk is the estimated probability and severity of adverse health effects in exposed populations consequential to hazards in food. Understanding the association between a reduction in hazards that may be associated with a food and the reduction in the risk of adverse health effects to consumers is of particular importance in development of appropriate food safety controls. Unfortunately, there is no such thing as "zero risk" for food (or for anything else).
The risk analysis process comprises three separate elements: risk assessment, risk management and risk communication. It is widely recognized as the fundamental methodology underlying the development of food safety standards. Decisions are needed to determine what the hazards are and to identify their immediate, interim and long-term effects on human health (risk assessment); to establish the appropriate measures of control to prevent, reduce or minimize these risks (risk management); and to determine the best way to communicate this information to the affected population (risk communication).
Risk assessment is a quantitative evaluation of information on potential health hazards from exposure to various agents. It involves four interrelated steps:
· Identification of the hazard and comprehension of the danger it represents, the impact in terms of human health and the circumstances under which the danger is present (hazard identification)
· Qualitative and/or quantitative evaluation of the adverse effects of the hazard on human health (hazard characterization)
· Qualitative and/or quantitative evaluation of the likely degree of consumption or intake of the hazardous agent (exposure assessment)
· Integration of the first three steps into an estimate of the likely adverse effect in the target population (risk characterization)
The entire risk assessment process requires the use of sound and scientifically derived information and the application of established scientific procedures carried out in a transparent manner. Unfortunately, sound scientific data are not always available for the qualitative and quantitative evaluations necessary for an absolutely sure final decision; consequently a degree of uncertainty must be factored into the decision.
The importance of risk assessment lies not only in its capacity for estimating human risk, but also in its function as a framework for organizing data as well as for allocating responsibility for analysis. The risk assessment process can include a variety of models for reaching conclusions; for example, the concept of acceptable daily intake (ADI) may be considered a component of risk assessment.
Biological hazards of concern to public health include pathogenic strains of bacteria, viruses, helminths, protozoa, algae and certain toxic products they may produce. Of these hazards, pathogenic bacteria in foods currently present the most significant problems internationally. Assessment of the risks associated with bacterial pathogens presents unique complications. Any method for assessing the risk of hazards from foodborne bacteria will be complicated by factors related to methods used to grow, process and store food for consumption. These factors can vary greatly depending on cultural and geographical differences. Such factors characterize the scenario for a given food and are an essential element for a risk assessment for bacterial hazards.
In many cases sufficient data will not be available to support a quantitative assessment of risks associated with bacterial pathogens. For a number of reasons, including the many uncertainties associated with how and when an organism may express its pathogenic potential, it has not yet been determined whether a quantitative risk assessment approach is possible and appropriate for characterization of risk associated with foodborne bacterial pathogens. Thus, by default, a qualitative approach to characterizing risk may be the only current alternative. To bring about regulatory changes the scientific community must advance beyond qualitative microbial risk assessment and generate the data needed to make quantitative assessments. FAO/WHO consultations had difficulty with quantitative microbiological risk assessment, and one recommendation is to establish an FAO/WHO Expert Committee on Microbiological Risk Assessment.
Chemical risk assessment is a fairly well established process and in general permits the assessment of risks from long-term chronic exposure to a chemical. It includes the assessment of food additives, residues of pesticides and other agricultural chemicals, residues from veterinary drugs, chemical contaminants from any source and natural toxins such as mycotoxins and ciguatoxin.
Risk assessment requires evaluation of relevant information and selection of the models to be used in drawing inferences from that information. Further, it requires recognition of uncertainties and, when appropriate, acknowledgement that alternative interpretations of the available data may be scientifically plausible. Data uncertainties arise both from limitations on the amount of data available and from evaluation and interpretation of actual data obtained from epidemiological and toxicological studies. Model uncertainties arise whenever attempts are made to use data concerning phenomena that are likely to occur under other sets of conditions for which data are not available.
Risk management is defined within the Codex Alimentarius as the process of weighing policy alternatives in the light of the results of risk assessment and, if required, selecting and implementing appropriate control options including regulatory measures. The goal of the risk management process is to establish the significance of the estimated risk, to compare the costs of reducing this risk to the benefits gained, to compare the estimated risks to the societal benefits derived from incurring the risk and to carry out the political and institutional process of reducing the risk.
The outcome of the risk management process, as undertaken by committees within the Codex Alimentarius system, is the development of standards, guidelines and other recommendations for food safety. In the national situation it is likely that different risk management decisions could be made according to different criteria and different ranges of risk management options. Risk managers, in developing approaches to managing risk, use the risk characterization that results from the risk assessment process. Risk management decisions can be based on establishing safe handling procedures and practices, food processing quality and safety assurance controls and food quality and safety standards to control hazards in food. These standards must take into consideration the proper use of food additives which have been determined to be safe and their permitted levels and scientifically determined acceptable safe limits for contaminants and agricultural chemical residues in food, using the risk assessment process.
The outcome of the risk assessment process should be combined with the evaluation of available risk management options in order that a decision on management of the risk can be reached. Implementation of the management decision should be followed by monitoring of both the effectiveness of the control measure and its impact on the risk to the exposed consumer population, to ensure that the food safety objective is being met.
While research and scientific studies continue to provide the answers needed for making informed decisions in risk analysis related to hazards in food, the uncertainty and unresolved questions continue to cause concern to decision-makers. Only continued research and scientific study can provide the necessary answers. Until these answers are available, much of what is known about hazards and assessing and controlling risks is based on only partial information, with uncertainties factored into the analysis.
Risk communication is the third and final element of the risk analysis process. The Codex Alimentarius definition of risk communication is narrow: "an interactive process of exchange of information and opinion on risk among risk assessors, risk managers and other interested parties". A definition with broader scope is that of the United States National Academy of Sciences: "an interactive process of exchange of information and opinion among individuals, groups and institutions... [which] involves multiple messages about the nature of risk and other messages, not strictly about risk, that express concerns, opinions or reactions to risk messages or to legal and institutional arrangements for risk management".
Communicating the results of risk assessment and risk management serves many purposes. The quality and safety of food depends on responsible action by all involved at all stages in the food chain, including consumers. Consumers require access to adequate information about potential hazards and appropriate precautions to be taken in the final preparation and serving of food. In addition, consumers need to be aware of and to understand food safety control measures implemented by their government in the interest of consumers' health.
Communication provides the public with the results of expert scientific review of food hazard identification and assessment of the risks to the general population or to specific target groups such as infants or the elderly. Certain people, such as those who are immunodeficient, allergic or nutritionally deficient, require particular information. Communication provides the private and public sectors with the information necessary for preventing, reducing or minimizing food risks to acceptably safe levels through systems of food quality and safety management by either mandatory or voluntary means. It also provides sufficient information to permit the populations with the greatest level of risk from any particular hazard to exercise their own options for achieving even greater levels of protection.
This training manual on food quality and safety systems is intended for trainers in food quality and safety assurance at the government and industry levels. It focusses on food hygiene practices and the Hazard Analysis and Critical Control point (HACCP) system. The manual consists of three sections: Principles and methods of training; Recommended International Code of Practice - General Principles of Food Hygiene; and The Hazard Analysis and Critical Control Point (HACCP) system. The last two sections were designed to reflect the recommendations and guidelines of the Codex Alimentarius Commission on food hygiene and HACCP worldwide. Each section is divided into specific training modules. This format allows the instructor to select sections and modules according to the levels of knowledge, experience and specific responsibilities of the students.