500 likes | 731 Views
Why Risk Analysis?. General public concern over real or imaged food-borne hazards to health Recognition of the absence of systematic framework for assessing the risks associated with food in international trade
E N D
Why Risk Analysis? General public concern over real or imaged food-borne hazards to health Recognition of the absence of systematic framework for assessing the risks associated with food in international trade Inclusion of risk assessment principles in national legislation and new legislative conditions that facilitate product-liability claims Trade agreements that require scientific validation of food safety (sanitary) measures used by national governments (SPS directs members to base national measures on risk assessment as appropriate to the circumstances)
Structure of Risk AnalysisA Scientifically Based Process • Risk Assessment • Hazard Identification • Hazard Characterization • Exposure Assessment • Risk Characterization • Risk Management • Risk Evaluation • Option Assessment • Option Implementation • Monitoring and Review • Risk Communication
Why Risk Assessment • The scientific evaluation of known or potential adverse health effects resulting from human exposure to food borne hazards • First step in risk analysis • Provides very useful output • annual occurrence of illness • annual rate of illness per 100 000 population
The Steps in Risk Assessment 1. Hazard Identification: The identification of known or potential health effects associated with a particular agent 2. Hazard Characterization: The qualitative and quantitative evaluation of the nature of the adverse effects associated with biological, chemical, and physical agents which may be present in food. For chemical agents a dose response assessment should be performed. For Biological?
The Steps in Risk Assessment 1. Exposure Assessment: The qualitative and quantitative evaluation of the degree of intake likely to occur 2. Risk Characterization: Integration of hazard identification, hazard characterization and exposure assessment into an estimation of the adverse effects likely to occur in a given population, including attendant uncertainty
Statements of Principle Relating to the Role of Food Safety Risk Assessment 1. Health and safety aspects of codex decisions and recommendations should be based on a risk assessment, as appropriate to the circumstances 2. Food safety risk assessment should be soundly based on science, decisions should take into account the uncertainty in the output of the risk assessment
Statements of Principle Relating to the Role of Food Safety Risk Assessment 3. There should be a functional separation of risk assessment and risk management, while recognizing that some interactions are essential for a pragmatic approach 4. Risk assessment should use available quantitative information to the greatest extent possible and risk characterizations should be presented in a readily understandable and useful form
General Principles of Microbiological Risk Assessment • Microbiological risk assessmentshould be soundly based upon science • There should be a functional separation between risk assessment and risk management • Microbiological risk assessmentshould be transparent • Microbiological risk assessmentshould clearly state the purpose of the exercise, including the form of risk estimate that will be the output
General Principles of Microbiological Risk Assessment • Microbiological risk assessmentshould be conducted according to structured approach that includes • Hazard Identification • Hazard Characterization • Exposure Assessment • Risk Characterization
General Principles of Microbiological Risk Assessment • Any constraints that impact on the risk assessmentsuch as cost, resources or time, should be identified and their possible consequences described • The risk estimate should contain a description of uncertainty and where the uncertainty arose during the risk assessment process
General Principles of Microbiological Risk Assessment • Data should be that uncertainty in the risk estimate can be determined Data and data collection systems should be, as far as possible, be of sufficient quality and precision that uncertainty in the risk estimate is minimized • Where possible risk estimates should be reassessed over time by comparison with independent human illness data • A Microbiological Risk Assessment may need re-evaluation, as new relevant information becomes available
General Principles of Microbiological Risk Assessment • A Microbiological Risk Assessment should explicitly consider • the dynamics of microbiological growth, • survival, and • death in foods, and • the complexity of interaction between human and agent following consumption • as well as the potential for further spread
Guidelines for Application • General considerations • Statement of purpose of Risk Assessment • Hazard Identification • Exposure assessment • Hazard characterization • Risk characterization • Documentation • Reassessment
Risk Management The process of weighing policy alternatives to accept, minimize or reduce assessed risks and to select and implement appropriate options
Elements of Risk Management 1. Risk Evaluation • Identification of a food safety problem • Establishment of a risk profile • Ranking of the hazard for risk assessment and risk management priority • Establishment of risk assessment policy for conduct of risk assessment • Commissioning of risk assessment • Consideration of risk assessment results
Elements of Risk Management 2. Risk management option assessment • Identification of available management option • Selection of preferred management option, including consideration of an appropriate safety hazard • Final management decision
Elements of Risk Management 3. Implementation of management decision 4. Monitoring and review • Assessment of management decision • Review risk management and/or assessment necessary
General Principles of Food Safety Risk Management 1. Risk management should follow a structured approach • Risk evaluation • Risk management option assessment • Implementation of management decision • Monitoring and review
General Principles of Food Safety Risk Management 2. Protection of human health should be the primary consideration in risk management decision Areas of considerations • Economic costs • Benefits • Technical feasibility • Societal preference
General Principles of Food Safety Risk Management 3. Risk management decision and practices should be transparent • Identification and systematic documentation of all elements of the risk management process including decision making 4. Determination of risk assessment policy should be included as a specific component of risk management
General Principles of Food Safety Risk Management 5. Risk management should insure the scientific integrity of the risk assessment process by maintaining the functional of risk management and risk assessment 6. Risk management decisions should take into account the uncertainty in the output of the risk assessment
General Principles of Food Safety Risk Management 7. Risk management should include clear, interactive communication with consumers and other interested parties in all aspects of the process 8. Risk management should be a continuing process that takes into account all newly generated data in the evaluation of and review of risk management decisions
General Principles of Food Safety Risk Management 9. Risk management decisions should address the whole farm to table continuum including imported goods 10. Risk management decisions should be reviewed as new information become available 11. The efficacy of risk management measures has to be periodically assessed with regard to the risk management goals. These measures have to be reviewed if appropriate.
Who Does What?Codex Committees and Risk Management Codex committees on: • Food Additives and Contaminants (CCFAC) • Residues of Veterinary Drugs in Food (CCRVDF) • Pesticides Residue (CCPR) • Food Hygiene (CCFH) • General Principles (CCGP) • Food Labeling (CCFL) • Food Import & Export Inspection and Certification System (CCFICS) • Nutrition and Foods for Special Dietary Uses (CCNSFDU) • Methods of Analysis and Sampling (CCMAS)
Who Does What?Independent Expert Bodies and Risk assessment Joint FAO/WHO Expert Committee on Food Additives (JECFA) • Food Additives • Contaminants (CCFAC) • Residues of Veterinary Drugs in Food (CCRVDF) Joint FAO/WHO Meeting on Pesticide Residues (JMPR) • Pesticides Residue (CCPR)
Main TasksIndependent Expert Bodies JECFA • Toxicological evaluation • Setting specification for identity and purity Toxicological • Toxicological studies in the most sensitive species • Determination of the No observed adverse effect level (NOAEL) • Adequate safety factors • Estimation of the acceptable daily intake (ADI)
Main TasksIndependent Expert Bodies JECFA Acceptable Daily Intake : An estimates of the amount of a substance in food drinking water, expressed on a body weight basis, that can be ingested daily over a lifetime without appreciable health risk • Assures no hazard to the consumer • Based on risk assessment and safety factors: extrapolation to human 10 x difference between humans 10 x • Overall safety factor, 100 x • Additional safety factors (2-10 x) if data are uncertain
Main TasksIndependent Expert Bodies JECFA Toxicological Evaluation of Contaminants • With threshold PTWI: Provisional Tolerable Weekly Intake • No threshold ALARA: As Low As Reasonably Achievable
Main TasksIndependent Expert Bodies JECFA Food Additives JECFA ADI Codex Maximum Level Codex Committee on Food Additives and Contaminants
Main TasksIndependent Expert Bodies JECFA Chemical Contaminants JECFA PTWI Codex Maximum Level Codex Committee on Food Additives and Contaminants
Main TasksIndependent Expert Bodies JECFA Veterinary Drugs JECFA ADI & MRL Codex Committee on Residues of Veterinary Drugs in Foods Codex MRLs
Main TasksIndependent Expert Bodies JMPR • Review of pesticide use patterns • Toxicological assessment • Exposure assessment • Proposes MRLs, based on Good Agricultural Practices (GAP) • Estimates ADI, based on Toxicological Evaluation • Compares with ADI, using MRLs and exposure estimates
Main TasksIndependent Expert Bodies JMPR FAO Panel of Experts on Pesticides in Food • Review of pesticides use patterns (GAP), chemistry and composition and methods of analysis • Propose maximum residue limits • Exposure assessment with WHO group WHO Experts Groups on Pesticides Residues • Toxicological assessment • Environmental assessment • Public and occupational health assessment • Exposure assessment with WHO group
Main TasksIndependent Expert Bodies JMPR Pesticides Residues JECFA ADI & MRLs Codex MRLs Codex Committee on Pesticide Residues
Other Expert Bodies For Microbiological Agents Agents (bacteria, viruses, etc) • International Commission on Microbiological Specification for Food (ICMSF)? • Codex Committee on Meat Hygiene (CCMH) • Codex Committee on Food Hygiene (CCFH) • Recommendation in the form of codes of Hygienic practices • General principles of food hygiene • HACCP
Risk Assessment of Chemical Agents in Food Hazard identification • Epidemiological studies Data derived from human clinical studies, genetic pridisposition, age and gender related susceptibility, socio economic status, nutritional status • Animal studies Animal data from long term (chronic) studies Animal data from short term (acute) toxicity studies No Observed Effect Level (NOEL) No Observed-Adverse Effect Level (NOAEL) Maximum Tolerated Dose (MTD)
Risk Assessment of Chemical Agents in Food Hazard characterization • Dose response extrapolation Uncertainty in extrapolation Hazard may change with dose or may disappear Change in metabolism with dose • Dose-scaling (mg per kg of body weight) • Genotoxic and non-genotoxic carcinogens • Threshold approaches (ADI) • Non-threshold approaches Ban the chemical from commercial use Establish a level of risk that is sufficiently Small (negligible)
Risk Assessment of Chemical Agents in Food Exposure Assessment Estimates dietary intake of food additives, residues of pesticides , and veterinary drugs and contaminants • Total diet studies • Selective studies of individual foods • Duplicate portion studies • Direct monitoring of human tissues and body fluids • Detailed food consumption data • Staple foods from different regions
Risk Assessment of Chemical Agents in Food Risk Characterization Estimate of the likelihood of adverse effects in human populations as a consequence of the exposure • Threshold < ADI adverse effects is nationally zero • Non-threshold acting agents population risk is the product of exposure and potency • Uncertainties with respect to the relevance of the experimental findings of human • Uncertainties with respect to the specific human sensitivity for effects of a chemical that can not be studied in experimental animals
Risk Assessment of Biological Agents in Food Food will always present minimal biological risk Biological agents of concern • Bacteria • Viruses • Protozoa • Algae Standards and codes of practices HACCP
Risk Assessment of Biological Agents in Food General mechanisms in causing human illness by Biological Hazards • Produce toxins which may cause effects that range from mild symptoms of short duration to severe intoxications that can have long term or life threatening consequences (Threshold level easier to quantify) • Produce pathological responses that result from ingestion of viable organism capable of infecting host (qualitative risk assessment)
Risk Assessment of Biological Agents in Food Hazard identification • Epidemiological studies Limitations • The expense and difficulty involved in outbreak investigations • The lack of reliable or complete epidemiological data • The inability to isolate and characterize new pathogens
Risk Assessment of Biological Agents in Food Hazard characterization: to provide qualitative or quantitative estimates of the severity and duration of adverse effects due to the presence of pathogen in food Limitations • host susceptibility to pathogenic bacteria is highly variable • attack rates from a specific pathogen vary widely • virulence of a pathogenic species is highly variable • pathogenicity is subject to genetic variation resultant from frequent mutation • Foods will modulate the ability of bacteria to infect and/or otherwise affect the host
Risk Assessment of Biological Agents in Food Exposure Assessment: an estimate of either the number of pathogenic bacteria or the level of bacterial toxin in food Limitations • Ecology of the bacterial pathogen concern • Processing, packaging and storing of food • Preparation steps, such as cooking, which may inactivate bacterial agents • Cultural factors relating to consumers
Risk Assessment of Biological Agents in Food Risk characterization: depend on the considerations and information described in the hazard identification, hazard characterization and exposure assessment steps. Qualitative estimate of the potential for adverse effects from a particular agent on a specific population Quantitative?
Risk Analysis and Hazard Analysis Risk Analysis: is the systematic evaluation of the risks arising from hazards in food, including risk assessment, management and communication and normally a clear statement as to whether an attribute of the food safety and to what degree it represents a food safety risk. Hazard Analysis: is frequently based on qualitative observations and qualitative evaluation of information relating to food processing and handling operations. HACCP: is a risk management option