Food safety and public health risks associated with products of aquaculture

摘要

The Sanitary and Phytosanitary (SPS) Agreement within the framework of the World Trade Organization emphasizes the need to apply risk analysis as a basis for taking any SPS measure. With the adoption of the food-chain approach for food safety, the responsibility for the supply of safe food is shared along the entire food chain from primary production to final consumption. Thus the application of risk analysis to the aquaculture sector, which produces nearly half the fish that is consumed worldwide, has become very important. Guidelines for performing risk analysis have been brought out by the Codex Alimentarius Commission or Codex. Risk analysis is a process consisting of risk assessment, risk communication and risk management. Risk assessment is the scientific evaluation of known or potential adverse health effects resulting from human exposure to foodborne hazards. This consists of four steps: hazard identification, hazard characterization, exposure assessment and risk characterization. The output of risk assessment may be a qualitative or a quantitative (numerical) expression of risk as well as attendant uncertainties. Hazard identification considers epidemiological data linking the food and biological/chemical agent to human illness and the certainty associated with such effects. At the hazard characterization step, a qualitative or quantitative description of the severity and the duration of the adverse health effect that may result from the ingestion of the micro-organism/toxin/chemical contaminants is made. During exposure assessment, an estimate of the number of bacteria or the level of a biotoxin or chemical agent consumed through the concerned food is made. The Codex defines the risk characterization step as the process of determiningthe qualitative and/or quantitative estimation including attendant uncertainties of the probability of occurrence and the severity of the known or potential adverse health effect in a given population based on hazard identification, exposure assessment and hazard characterization. As an example of a risk assessment, the Food and Agriculture Organization of the United Nations/World Health Organization risk assessment for choleragenic Vibrio cholerae in warmwater shrimp in international trade is presented. Risk management is 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. Risk communication is an interactive process of exchange of information and opinion on risk among risk assessors, risk managers and other interested parties. Examples of risk management measures adopted based on risk assessment are presented.