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

More Evidence of IARC Data Suppression and Manipulation

A Reuters special report released last week highlights how the International Agency for Research on Cancer’s (IARC) Monographs Program edited out “non-carcinogenic” findings from its glyphosate review. Released in March 2015, IARC’s Monograph 112 report labeled glyphosate as a “Group 2A” carcinogen, meaning that it probably causes cancer in humans.  According to Reuters, a key section of IARC’s assessment underwent significant changes and deletions before the report was finalized, ultimately influencing the agency’s classification of the world’s most popular herbicide.

The edits, which were made to a 10-page chapter of the 92-page report that focused on animal studies, included repeat evidence of:

  1. Data Deletion: IARC scientists deleted conclusions by multiple scientists that their studies found no link between glyphosate and cancer in animals. For example, IARC altogether removed a comment that said pathologists, commissioned to reinvestigate the results of a 1983 mouse study under IARC evaluation, “unanimously” agreed with the original conclusions that found “no statistically significant link between glyphosate and cancer in mice.”
  2. Data Manipulation: IARC scientists supplanted existing data with new statistical data – “effectively reversing the original finding of a study under IARC review.”  The new calculation came to the exact opposite conclusion of the original study data. Altogether, there were 10 instances where IARC scientists removed or swapped a negative conclusion about glyphosate’s link to cancer with a “neutral or positive one.”

Keep in mind Reuters had access to just over 10% of the original report. What other edits exist in the original report?


Repeat Offenders

This latest revelation comes on the heels of two earlier reports of data suppression by IARC scientists. As POLITICO reported last August, Charles Jameson, an American toxicologist and chairman of the Working Group’s animal studies subgroup, told lawyers in a sworn deposition that IARC failed to share with his group two other German studies that showed no link between glyphosate and cancer.

Reuters also reported last June how the chairman of the IARC Working Group, former National Cancer Institute employee Aaron Blair, had withheld new data from the prominent Agricultural Health Study, which showed no link between glyphosate and cancer in humans from the Working Group.

Together, those discoveries prompted a congressional investigation by the House Oversight Committee Chairman Trey Gowdy on why IARC intentionally buried key research – research that would have reversed IARC’s conclusion on glyphosate.

IARC’s conclusion on glyphosate has proven to be an outlier, with other regulatory bodies coming to contradictory conclusions. A year after IARC issued its evaluation, a joint United Nations and World Health Organization panel reviewed the potential for glyphosate in food to cause cancer in people. It concluded the weedkiller was “unlikely to pose a carcinogenic risk to humans.” In addition, the European Food Safety Authority (EFSA) and European Chemicals Agency (ECHA) both concluded that scientific evidence did not support classifying glyphosate as a carcinogen.

Rather than respond to criticisms, IARC has taken steps to reduce transparency. Last year, Reuters reported on an IARC email to members of the glyphosate Working Group advising them not to discuss their work or disclose documents. Reuters’ report today also notes that after being asked about the changes made to the animal studies section, IARC posted the following statement on its website:

“Members of the IARC Monograph Working Group which evaluated glyphosate in March 2015 have expressed concern after being approached by various parties asking them to justify scientific positions in draft documents produced during the Monographs process. IARC would like to reiterate that draft versions of the Monographs are deliberative in nature and confidential. Scientists should not feel pressured to discuss their deliberations outside this particular forum.”

This latest report further diminishes the credibility of IARC’s Monographs Program, its carcinogenic classifications, and the agency at large.  As CAPHR has emphasized, sound science relies upon a foundation of fair and even-handed review of data, clear communication with the public, and transparency. IARC lacks all of the above, bringing its scientific integrity into question. Reform of its Monographs Program is urgent and overdue.