[Call for Experts] WHO initiative to evaluate PFAS

February 19, 2024

The World Health Organization (WHO) is seeking experts to serve as members of an ad-hoc expert group to assist WHO with an upcoming assessment of the risks to human health from PFAS.

This call for experts provides information about the upcoming WHO assessment, the role of the expert group, the expert profiles being sought, and the application and selection process.

1. Background

Public health concern about human exposure to per- and polyfluoroalkyl substances (PFAS), including from exposure through drinking-water and food, is increasing. A number of countries and authorities have published or proposed guidance values for PFAS in drinking-water in recent years, but the values which have been proposed vary considerably. New data for these substances are continually published, and there are significant uncertainties in the extrapolation of laboratory toxicological data to human health effects for these chemicals, which means that assessments rely significantly on expert judgement. Hence, there is a lack of consensus about the levels of PFAS which may be a health concern.

Given the discrepancies in values established or proposed by various authorities, a systematic collection and assessment of the evidence is warranted to establish health-based values. WHO is hiring a contractor(s) to lead systematic collection and assessment of the evidence, which will be conducted in three parts that include (1) Landscape review on health effects of PFAS, (2) Methodology development for an in-depth assessment of the risk to human health of PFAS from exposure via ingestion, and (3) Provision of guidance to ensure that the activities listed under (1) and (2) align with best practices in collection, synthesis and review of the evidence. WHO is convening an expert group to provide input and to support finalization of this work, through online consultations and an expert meeting.

Future work is also envisaged by WHO to undertake a more in-depth assessment of PFAS on the key end-points of concern, with a view to establish health-based guidance values. This could be a starting point to establish values for consideration by WHO’s normative and standard-setting processes to address the risks to human health from chemical contaminants in drinking-water, in food and through occupational exposure to chemicals.

2. Objective of the call

The objective of the call is to identify qualified experts who are willing to serve as a member of the expert group for WHO’s initiative on PFAS. Terms of reference of the group are (in brief) to:

  • Undertake expert review of the methods, summary and conclusions of the landscape review and evidence synthesis developed by the contractor(s);
  • Advise WHO on methodologies to evaluate PFAS;
  • Advise WHO on most relevant PFAS and end-points to focus on for the in-depth assessment.

3. Basic and essential qualifications of experts

Successful candidates should meet many or most of the following qualifications:

  • Hold an advanced university degree(s) in a relevant field of study (e.g. toxicology, pharmacology, biochemistry, pathology, epidemiology, immunology, environmental sciences, engineering, biostatistics);
  • Scientific excellence evidenced by publications in peer-reviewed specialized journals, government publications or similar;
  • Professional experience in one or more of the following technical areas:
    • Risk assessment processes, in particular processes relevant for FAO/WHO JECFA, Codex, the GDWQ and other international assessments
    • Protocols and best practices for systematic collection and synthesis of evidence on human health effects and occurrence/exposure for chemicals, including chemicals with extensive data sets and complex mixtures, ideally PFAS, in water and food
    • Methodologies to derive health-based values, considering mixture approaches (combined and cumulative exposure), including ideally PFAS
    • Reviewing, evaluating, and extrapolating experimental, animal, and other biological data on toxic chemicals to humans, including identifying data gaps and areas for more in-depth assessment, including ideally for PFAS
    • Evaluating chemicals as contaminants, including ideally PFAS
    • Chemical identification, nomenclature and analytical chemistry, including ideally PFAS
    • Monitoring and managing PFAS in drinking-water supplies
  • Familiarity with WHO’s requirements for developing normative publications, including the Guidelines for drinking-water quality and other WHO normative and standard-setting products relating to chemicals;
  • Experience in contributing to scientific assessments at the national or international level;
  • Ability to converse in and write documents in English;
  • Ability to participate in virtual and in-person expert consultations (first in-person consultation anticipated to take place in the second half of 2024);
  • Ability to work with people from different cultural backgrounds as well as with scientists from various disciplines.

4. Application

Interested applicants are invited to submit their curriculum vitae (no more than 10 pages in A4 format), and filled Declaration of Interest (DoI), and a list of publications, no later than 19 February 2024 (CET). An applicant shall be made available by his or her employer for engaging in this WHO work and be released for an international in-person meeting at least once a year and ad hoc virtual meetings.


Apply and view additional information here.