Background
The Joint FAO/WHO Meeting on Pesticide Residues (JMPR) is an independent international expert body jointly administered by the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO). Since 1963, JMPR has met annually to conduct scientific evaluations of pesticide residues in food and to provide advice on acceptable levels of pesticide residues in commodities traded internationally. Its recommendations form the scientific basis for the establishment of Maximum Residue Limits (MRLs) by the Codex Alimentarius Commission.
Prospective dietary exposure assessment is one of the key parts of JMPR’s risk evaluation of pesticide residues. JMPR conducts both chronic (long-term) and acute (short-term) assessments using established methodologies: chronic exposure via the International Estimated Daily Intake (IEDI), which combines Supervised Trial Median Residue (STMR) values with food consumption data to compare against the Acceptable Daily Intake (ADI), and acute exposure via the International Estimated Short-Term Intake (IESTI), which considers high percentage of consumption and Highest Residues (HR) relative to the Acute Reference Dose (ARfD). To better address global consumption patterns, JMPR has also begun trialing the Global Estimated Chronic Dietary Exposure (GECDE) approach, including GECDE–high and GECDE–mean models. However, methodological questions remain regarding the definition of the exposure scenarios of potential concern, in relation to chronic or less-than-lifetime toxicological effects, how models may address them, and approaches to ensure chronic and shorter-than-life risk assessments consistently and transparently reflect population exposure across regions.
At its 56th session, the Codex Committee on Pesticide Residues (CCPR), requested additional information from JMPR on developments in dietary exposure methodologies, citing concerns about transparency, conservativeness, and dissenting opinions. In response, FAO and WHO plan to convene an ad hoc expert meeting to independently review the methodology. The purpose of this ad hoc expert meeting is to define the exposure durations to be modelled to address less-than-lifetime toxicological effects, to review and compare the methodologies currently available to address those exposure durations, other relevant approaches, and make recommendations to FAO and WHO and address concerns raised in CCPR56.
The continued application and refinement of these methodologies are essential to ensure that dietary risk assessments remain scientifically sound, robust, and transparent. FAO and WHO therefore call for qualified experts to contribute to forthcoming work on dietary exposure assessment of pesticide residues in food.
The meeting is expected to take place from 28 September to 2 October 2026, location to be determined. The working language is English.
Objective of the meeting
The objectives of the meeting are to:
- Define the less-than-lifetime exposure durations of potential toxicological concern, including those that are life-stage specific.
- Review and compare the methodologies currently available to address these exposure duration; if such methodologies are not available, define how these exposure duration should be modelled.
- Technically review and assess the GECDE model concept and compare its performance with that of other exposure assessment models available to address less-than-lifetime toxicological effects, with particular focus on the GECDE–high model.
- Review the strengths, limitations, and assess uncertainties and potential impacts associated with each model.
- Discuss how transparency, scientific robustness, and representativeness of the prospective methods can be ensured in relation to the level of protection required and ideally with actual dietary exposures to pesticide residues.
- Discuss how the results can be transparently and meaningfully reported, so that they can be interpreted and considered appropriately by the Codex Alimentarius Commission (CAC) for future standard-setting.
- • Provide recommendations on decision-making during the risk assessment process, taking uncertainties and conservativeness into account, and clearly communicating the implications to risk managers.
Topics to be discussed during the consultation
Experts invited to this ad hoc meeting will contribute to discussions on methodological approaches and practical considerations in dietary exposure assessment of pesticide residues. Key topics include:
- Characterization and definition of exposure scenarios: to consider the toxicological scenarios (chronic, life-stage, and less-than-lifetime exposure, acute) of potential concern and review the strengths, limitations, and uncertainties in defining these scenarios.
- Technical review of the GECDE Model approach: to validate the GECDE model approach and analyze its suitability for establishing pesticide MRLs.
- Exposure methodologies assessment: evaluation of IEDI and IESTI versus GECDE approaches; assessing the impacts of application and relevance of GECDE–mean and GECDE–high models.
- Alignments with toxicology: matching exposure duration to effect type (acute, chronic, sub-chronic), considering sensitive periods and life stages. Characterize vulnerable subpopulations with respect to the toxicological effects.
- Risk characterization: to evaluate how various exposure methodologies perform across different toxicological scenarios.
- Residue considerations: to compare MRL setting based on field trial data versus monitoring data of raw agricultural commodities and/or foods as consumed to reflect actual exposure to pesticide residues; Discuss options for refining assessments when exceedances occur.
- Results communication: identification of driving food items (in consumption surveys) and driving commodities (in field trial data), affected populations-regions, magnitude of exceedances, and relevant toxicological effects underpinning Health-Based Guidance Values (HBGVs), including reporting to CCPR. Should all scenarios be reported for all substances, or only those where there is a potential toxicological concern? Discuss the table format in which the results need to be reported.
- Food consumption data: to discuss quality criteria for survey inclusion, percentiles for high-residue calculations, aggregation of age groups, and recipe development.
- Recommendation on the approach to enhancing transparency and addressing the conservativeness and its impacts.
Expertise and resources requried
FAO and WHO are looking for experts to contribute to forthcoming work in the area of dietary exposure assessment of pesticide residues in food. All applicants should meet the following general criteria:
- Advanced University/College degree or show appropriate professional expertise in residue chemistry, statistics, epidemiology, toxicology, public health, agriculture, food safety, international food trade, or related fields;
- At least five years of experience in one or more relevant fields:
- Dietary exposure assessment of pesticides or chemicals, including familiarity with IEDI, IESTI, GECDE, and related models;
- Probabilistic modeling, uncertainty analysis, and model validation for exposure assessment;
- Pesticide residue evaluation, familiar with the relationship between raw commodities and foods as consumed, evaluation of dietary survey data quality and aggregation, and understanding of health-based guidance values (ADI, ARfD, HBGVs), exposure-duration relationships, sensitive life stages, and relevant toxicological endpoints.
- Food safety, particularly of residues of pesticides.
- Scientific publications in peer-reviewed journals or in scientific reports, in particular, relevant publications within the last ten years on the topics related to this meeting;
- Evidence of leadership or invited participation in national or international scientific bodies, committees, and other expert advisory bodies pertinent to the scope of this work.
Applications
- Interested applicants should complete the online application and submit their Curriculum Vitae (CV) at: https://extranet.who.int/dataformv6/index.php/739428?lang=en
- The CV should include a description of education, relevant work experience, evidence of national or international expertise on the topic, including a list of peer-reviewed publications or other scientific documents relevant to the factors indicated above (please do not include reprints in your submission unless specifically requested at a later date). Applicants must have a good working knowledge of English, as correspondence and meetings will be in English only.
Deadline of application
Please make application and submit CVs at your earliest convenience, but no later than 30 March 2026.
Selection of experts
Applicants' CV will be reviewed based on the criteria listed above by a selection panel consisting of three or more individuals appointed by FAO and WHO. All qualified individuals will be notified and added to the JMPR roster of experts that is also valid for future work. Selected experts may be expected to assist in the preparation of background papers and report drafts (in English). In selecting experts, FAO and WHO will consider, in addition to scientific and technical excellence, diversity and complementarities of scientific backgrounds, and balanced representation across different technical areas and disciplines, geographic regions, including developing and developed countries, as well as gender. Unselected candidates are not routinely notified.
Expert invitation
Selected experts will be invited by joint secretariat to contribute to the meeting only in their individual scientific capacity. An expert will not represent the government of the country of which he or she is a citizen, or the institution with which he or she is associated. The experts designated will not receive any remuneration; however, where a physical expert meeting is held, travel costs, subsistence allowance, and other related expenses will be the exclusive responsibility of FAO and WHO.
Management of the conflict of interests
Before participating in any related activity, all the selected experts will be required to declare any potential interests associated with the subjects and substances that will be evaluated. Experts will be asked to indicate, in writing, all interests (financial and intellectual) on their part or that of their spouse that may affect, or be perceived to affect, their scientific independence as experts, including one or more of the following conditions: (i) employment (past or present) by any commercial enterprise or private or civil sector association; (ii) receipt of research or other study grants from such enterprises or associations; and (iii) shareholdings in commercial enterprises active in fields related to food safety.
Identification of an interest does not necessarily indicate a conflict nor automatically exclude an individual from participation. For example, as an expert, it is expected that many, if not all, will be employed in some capacity related to the subject matter. These declarations must be completed and evaluated before a formal invitation will be issued. Declaration documents will be retained by the Joint Secretariat, and a summary of declarations will be included in the report of the work. In addition, a confidentiality undertaking must also be completed prior to appointment to ensure proper handling of dossiers and proprietary information.
Any questions regarding this call for exerpts shoud be sent to both:
Guibiao Ye
Division of Plant Production and Protection (NSP)
Food and Agriculture Organization of the United Nations
Viale delle Terme di Caracalla 00153, Rome, Italy
Email: jmpr@fao.org
Julianne De Oliveira Mota
Department of Nutrition and Food Safety (NFS)
World Health Organization
20 avenue Appia 1211, Geneva 27, Switzerland
Email: jmpr@who.int