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"By denying scientific principles, one may maintain any paradox." – Galileo Galilei

A Look at IARC’s Invite-Only Working Group Meetings and a Culture of Secrecy

By now we are familiar with IARC’s flawed Monographs Program and the controversy that envelopes its antiquated hazard-based carcinogen assessments. But little is known about the Working Groups that meet to deliberate on the carcinogenicity of various substances and produce Monographs, or official reports, on their findings. Here’s a deeper look inside the Working Group make-up and the closed-door culture of IARC’s Monographs Program.

 Working Group: Deconstructed

IARC’s Monographs Program Working Groups are a small, hand-picked cohort of scientists from around the world who are responsible for evaluating carcinogenic hazards of various chemicals that IARC has prioritized for review. After IARC lists a chemical for review, the agency makes a call for data and experts. Once selected, about 20-30 Working Group members then spend a week-long, all-expenses-paid visit to IARC’s headquarters in Lyon, France, to review a select set of scientific papers behind closed doors. In accordance with IARC’S preamble, Working Group members apply a decades-old, hazard-based evaluation approach to evaluate potential carcinogenic hazards. After five days of review and deliberation, Working Group members conclude (or, rather, have concluded 1,002 out of 1,003 times) that a substance poses a carcinogenic hazard to humans. Shortly after, IARC publishes a short summary of its official carcinogenic classification of the chemical. It is important to note, though, that the summary does not include any scientific data to justify its position. The data is only included in the official Monograph report, which is typically published by the Monographs Program anywhere between several months to nearly two years following the initial Working Group meeting in Lyon.

 Why This is Troublesome

 IARC’s Working Group structure and conclusions are problematic for several reasons.

  • The Working Group is not accountable to anyone. The Working Group serves as the judge by deciding what studies to include and what studies to exclude. It also serves as the jury by determining how to weigh and interpret studies, and determining the sentence – pronouncing guilt that a substance poses a carcinogenic hazard to The Group is also the Executive by pronouncing its official decree or carcinogenic classification via a Monograph, which can be used by regulatory bodies such as California’s Office of Environmental Health Hazard Assessment to implement policy and regulate businesses.
  •  Lack of Process, Accountability and Transparency. The Monographs Program also lacks a thorough process and comprehensive criteria for selecting studies. As a result, the Working Group may not have the best and highest-quality studies available to review. This was the case with the latest data from the Agricultural Health Study (AHS), the largest and most comprehensive study to date on glyphosate exposure. The AHS was excluded from review during the Working Group’s evaluation of glyphosate and the development of Monograph 112.
  • IARC does not require disclosure of bias by experts who review their own work or that of their close colleagues. As such, this is now common practice. Between 2012 and 2015, 61 scientistsworked on Monographs that cited their own research.
  • The classification process is also carried out without any substantive external accountability, or independent scientific peer review of their analyses, rationales, justifications or decisions.
  • Confusing Communications. Working Groups meet and develop hazard-based conclusions on a substance’s carcinogenicity that often mislead the public. IARC’s Working Group only evaluates potential hazards. They do not provide information on the actual risk associated with relevant levels of exposures. This causes unnecessary confusion and alarmism.

How to Fix the Working Group Problem

There are several things that IARC can implement to improve Working Group transparency and processes, and help build the credibility of the agency’s overall Monographs Program. Below are CAPHR’s principles for reform:

  • Require Reliance on Weight of Evidence— When making determinations in its monographs, IARC should give the most weight to those studies that are of the highest quality and greatest relevance to humans. Currently, IARC relies on a limited view of the available scientific evidence, which considers only selected findings, ignores conflicting evidence, and fails to fully consider the quality of individual studies. A weight of the evidence approach evaluates each relevant study for its strengths and limitations before its conclusions are used as part of the review.
  • Establish Standard Criteria for Selecting Studies— IARC should establish clearly defined, transparent criteria for assessing the quality and reliability of studies for its monograph reviews. Currently it is unclear how IARC determines which studies it will consider and which it will disregard.
  • Increase Transparency and Utilize Input from Stakeholders— IARC should openly engage with and allow participation from stakeholders during monograph development, including meetings with experts. IARC should clearly articulate in its monographs how it considered stakeholder input and provide stakeholders an opportunity to comment on a draft monograph.
  • Explain Conflicts of Interest— IARC should disclose all conflicts of interest among the participants and advisors to its working groups, not just those affiliated with industry. For example, IARC has not disclosed instances when its advisors and monograph working group members from the academic or NGO community may have a personal or professional stake in the outcome of the monograph.
  • Improve Monograph Releases— IARC should release all monograph information at one time and do away with its current practice of releasing short summaries of its findings months before supporting information is made public. IARC’s current publication practice fails to provide the evidence and exposure levels used to support its classifications of substances as carcinogenic, causing misunderstanding by media and the public.

IARC should implement these reforms to increase transparency and effectiveness of Working Group processes, and restore credibility in its flawed carcinogen assessments.