Food Safety Risk Assessment - International Scientific Panels
Risk assessment: scientific basis of food safety measures
FAO and WHO promote the application of risk assessment in all matters involving food safety. This must be based on sound scientific advice and evidence provided by panels of competent and independent experts. Risk assessment is one of the components of risk analysis - the other two being risk management and risk communication.
The Codex Alimentarius Commission (CAC) defines risk assessment as a scientifically based process consisting of the following four steps: i) hazard identification; ii) hazard characterization; iii) exposure assessment; and iv) risk characterization. The risk assessment process is a means of providing an estimate of the probability and severity of illness attributable to a particular pathogen-commodity combination. The four-step process enables this to be carried out in a systematic manner, but the extent to which the steps are carried out will be dependent on the scope of the risk assessment. This can be defined clearly by the risk manager through ongoing dialogue with the risk assessor.
Risk assessments provide information for identifying and characterizing food hazards. Risk assessment information is useful in determining which hazards are of such a nature that their prevention, elimination or reduction to acceptable levels is necessary. The information is also useful in determining the most effective intervention strategies.
At present, there are two long-standing panels that provide advice to Codex, governments and industry. They are the Joint FAO/WHO Expert Committee on Food Additives and Contaminants (JECFA) and the Joint FAO/WHO Meeting on Pesticide Residues (JMPR). In addition, FAO and WHO convene ad hoc expert consultations whenever needed to address specific issues not covered by the permanent panels. In recent years, several expert consultations have been held on microbiological hazards in food, the risk assessment of foods derived from biotechnology and on animal feeding and food safety. FAO and WHO are currently studying the possibility of establishing an overall expert body on food safety risk assessment that would oversee the entire work in this field and ensure the necessary link, synergy and harmony between the specific expert panels and consultations.
Joint FAO/WHO Expert Committee on Food Additives (JECFA)
The Joint FAO/WHO Expert Committee on Food Additives (JECFA) is an international expert scientific committee that is administered jointly by FAO and WHO. It has been meeting since 1956, initially to evaluate the safety of food additives. Its work now includes the evaluation of contaminants, naturally occurring toxicants and residues of veterinary drugs in food. To date, JECFA has evaluated more than 1300 food additives, approximately 25 contaminants and naturally occurring toxicants, and residues of approximately 80 veterinary drugs. The Committee has also developed principles for the safety assessment of chemicals in food that are consistent with current thinking on risk assessment and take account of recent developments in toxicology and other relevant sciences. As of June 2001 the Committee had met a total of 57 times.
JECFA serves as a scientific advisory body to FAO, WHO, and their member governments, and to the Codex Alimentarius Commission (CAC). Advice to the CAC on food additives, contaminants and naturally occurring toxicants is normally provided via the Codex Committee on Food Additives and Contaminants (CCFAC) and advice on residues of veterinary drugs via the Codex Committee on Residues of Veterinary Drugs in Foods (CCRVDF).
All countries need to have access to reliable risk assessments of chemicals in food, but relatively few have the expertise and funds available to carry out separate risk assessments on large numbers of chemicals. JECFA performs a vital function in providing a reliable source of expert advice, and some countries use information from JECFA in formulating their own regulatory programmes. In the same way, CCFAC and CCRVDF develop standards for chemicals in food based on JECFA evaluations.
For food additives, contaminants and naturally occurring toxicants, the Committee:
elaborates principles for evaluating their safety;
conducts toxicological evaluations and establishes acceptable daily intakes (ADIs) or tolerable intakes;
prepares specifications of purity for food additives; and assesses intake.
For residues of veterinary drugs in food, the Committee:
elaborates principles for evaluating their safety;
establishes ADIs and recommends maximum residue limits (MRLs);
determines criteria for the appropriate methods of analysis for detecting and/or quantifying residues in food.
For food additives, JECFA normally establishes ADIs on the basis of available toxicological and other relevant information. Specifications of the identity and purity are also developed for food additives, which help to ensure that the product in commerce is of appropriate quality, can be manufactured consistently, and is equivalent to the material that was subjected to toxicological testing.
For contaminants and naturally occurring toxicants, levels corresponding to 'tolerable' intakes such as the provisional maximum tolerable daily intake (PMTDI) or provisional tolerable weekly intake (PTWI) are normally established when there is an identifiable no-observed-effect level. When a no-observed-effect level cannot be identified the Committee may provide other advice depending on the circumstances.
In the case of veterinary drugs, data on good practice are evaluated and corresponding MRLs in animal tissues, milk or eggs are recommended. Such MRLs are intended to provide assurance that when the drug has been used properly, the intake of residues of the drug present in food is unlikely to exceed the ADI.
For more information, please see relevant FAO and WHO Websites:
FAO/WHO Joint Meeting on Pesticide Residues (JMPR)
The JMPR is comprised of the Joint Meeting of the FAO Panel of Experts on Pesticide Residues in Food and in the Environment and the WHO Core Assessment Group. JMPR carries out toxicological evaluation of pesticide residues, normally resulting in an estimate of the ADI. In addition, JMPR proposes maximum residues limits (MRLs) for individual pesticides in or on specific commodities. These MRLs are primarily based on the residue levels estimated in supervised field trials when the pesticide is used according to Good Agricultural Practices (GAP). In cases where initial estimates indicate that the ADI may be exceeded, more refined intake calculations are performed using national food consumption data and information from pesticide residues monitoring programmes.
These Expert Committees establish chemical safety standards based on a review of toxicological studies in the more sensitive test animal species. They factor in an adequate level of safety, use risk assessment procedures, consider use and consumption patterns and define the specifications of the identity and purity of food grade chemicals to be used.
For more information, please visit the relevant FAO and WHO
Microbiological risk assessment
Since 1999, and at the request of the CAC, FAO and WHO have initiated a series of joint expert consultations to assess risk associated with microbiological contamination of foods (JEMRA). This followed the adoption by the CAC of the Principles and Guidelines for the Conduct of Microbiological Risk Assessment (MRA).
The aim of these joint expert consultations is to provide a transparent review of scientific data on the state of the art of MRA, and to develop the means of achieving sound quantitative risk assessments of specific pathogen-commodity combinations. The work includes an evaluation of existing risk assessments; a review of the available data and current risk assessment methodologies, highlighting their strengths and weaknesses and how they may be applied; provision of examples; and identification of data and information needs/gaps. A further aim of these consultations is the development of guidelines relating to the different steps of risk assessment, such as hazard characterization and exposure assessment. The purpose of such guidelines is to help the risk assessor, the risk manager and other interested parties to understand the principles and science behind the risk assessment steps.
A series of such consultations have already been organized. They have dealt with the risk assessment of Salmonella spp in broilers, Salmonella Enteriditis in eggs, Listeria monocytogenes in ready-to-eat foods, Campylobacter in broiler chickens, and Vibrio spp. in seafood. The work plan and priorities for MRA are established in close collaboration with the Codex Committee on Food Hygiene.
For more information, please visit the FAO and WHO relevant
GM Food Risk Assessment
The use of modern biotechnology for the genetic modification of plants, microorganisms and animals for the production and processing of foods poses additional concerns to certain consumer groups. WHO and FAO recognize that modern biotechnologies have potential to raise agricultural productivity, reduce dependence on harmful chemicals and increase the nutritional value of foods. However, they also acknowledge that there are possible risks to human and animal health and to the environment, which require a case-by-case assessment.
FAO and WHO jointly organized a series of expert consultations to consider general safety and nutritional aspects of foods derived from modern biotechnology. The consultations addressed 'Strategies for Assessing the Safety of Foods Produced by Biotechnology' in 1990, 'Biotechnology and food safety' in 1996, and 'Safety aspects of genetically modified foods of plant origin' in 2000 and 2001. The latter consultations addressed specifically questions on safety that were raised by Codex Intergovernmental ad-hoc Task Force on Foods derived from Biotechnology. The 2000 Consultation reframed the concept of substantial equivalence and identified a set of priority issues that are to be addressed in future FAO and WHO consultations. The 2001 Consultation revised the international guidelines on the assessment of potential allergenicity of novel recombinant proteins to address broader concerns or critics of the previous approach. A second consultation in 2001 was convened to consider the criteria essential for the risk assessment of food and food ingredients produced with the aid of or containing viable or non-viable genetically modified micro-organisms.
For more information, please visit the FAO and WHO relevant
Selection of experts
FAO and WHO have complementary functions in selecting members for JECFA. FAO is responsible for selecting members to deal with the development of specifications for the identity and purity of food additives and the assessment of residue levels of veterinary drugs in food. WHO is responsible for selecting members to deal with the toxicological evaluations of the substances under consideration. Both FAO and WHO invite members who are responsible for assessing intake. The selection of members is made only after a careful consideration of the scientific credentials of the various candidates, and a balance of scientific expertise and other experience is considered essential. FAO and WHO have established rosters of experts from which individuals would be selected to serve at expert consultations. In order to establish rosters, FAO and WHO issue calls for applications, which describe the essential qualifications of the applicants, selection procedures for the roster and other relevant information. The rosters are posted on the respective WHO and FAO websites. FAO and WHO meet the costs of experts' attendance at JECFA meetings.
FAO, and WHO, have initiated a new approach for the identification, selection and nomination of its JMPR Panel Members. A roster call for submission of applications has been issued and given wide distribution.
This call describes the objective and criteria for Panel Membership. The review process of the applications received will be carried out in cooperation between FAO and WHO and with respected, well-known independent experts.
FAO/WHO New Procedure
A new procedure for the identification and selection of experts serving in joint FAO/WHO expert panels and consultations has been adopted in 2000 and has been applied since then. This new procedure enhances the principles of transparency, equal opportunity, excellence and independence, and seeks to harmonize the working procedures between different expert bodies and between FAO and WHO. This new procedure involves the following steps:
1. A call for experts is made in advance of each expert meeting. The call provides the background, objective and technical agenda of the expert meeting/consultation and indication of the profile required for the experts to be considered. It also includes clear indication of criteria to be used for selection, including expertise and workload involved. This call is disseminated widely, i.e. through Internet, communications to Member States, Codex Contact Points, and other relevant mailing lists.
2. A five-member selection panel composed of:
One representative of FAO (from the technical unit concerned);
One representative of WHO (from the technical unit concerned);
Three experts designated by FAO and WHO.
The panel reviews the applications and identifies those experts who fulfil all conditions stipulated in the call.
3. The retained applicants are requested to sign a standard "Declaration of Interest" and indicate institutional affiliation before their names are included in the roster. The roster is maintained by the Secretariat and is publicly available on Internet.
4. The Secretariat selects individuals from the roster to serve on a given expert meeting taking into account pre-established criteria, including the agenda of the meeting, the geographical representation, and the representation of different schools of thought, etc.
5. The Secretariat invites the experts and reminds them of the fact that they serve in their personal capacity and not as representatives of their respective governments or institutions. It also stresses the issue of confidentiality of the documentation, deliberations and conclusion until the report is issued.