IARC on RF: What’s Next?

Adapted from an article by Louis Slesin, PhD, June 11, 2021 | Original Microwave News article here.

In 2019, an IARC advisory group recommended — as a “high priority” — that the agency reassess the risk after the release of the NTP and Ramazzini animal studies, both of which showed increases in tumor counts following long-term RF exposure.1 The advisory group recommended that the reevaluation be completed between 2022 and 2024.

Briefing at the European Parliament

On May 30, just three days after colloquium of the German Federal Office of Radiation Protection (known as the BfS), the European Parliament held a briefing on 5G radiation and health at which Michèle Rivasi, a member from France, called for action. “It is time for IARC to reevaluate the impact of RF radiation on health,” she said.

Fiorella Belpoggi, the lead author of the Ramazzini RF–animal study, was the first speaker at the briefing. She has urged IARC to do a fresh cancer assessment ever since her findings were released in 2018.

Kurt Straif also spoke, and he too favors a new look at the RF-cancer risk. “I fully support the recommendation of the 2019 IARC advisory group,” he told me after the meeting. Straif was in charge of the IARC Monographs program when the RF working group evaluated RF radiation in 2011. He is now with the Barcelona Institute for Global Health (IS Global).

Any reevaluation would include “all eligible and pertinent evidence,” including the cancer epidemiology and the recent animal studies, Straif said.

Just a few weeks ago, Linda Birnbaum, the former director of the U.S. National Toxicology Program, together with a number of public health colleagues, advised the Italian government that when IARC takes the new animal data into account, RF will “certainly” be upgraded to at least a probable and perhaps even a proven human carcinogen. (Details here.)

A date for a new RF working group meeting has not been set, according to Veronique Terrasse in IARC’s Media Center. It would be announced “approximately one year in advance,” she said in an email. This means that it won’t happen before next summer, at the earliest.

As it happens, May 30 was the tenth anniversary of the IARC working group decision to label RF a 2B carcinogen.

By Invitation Only

The IARC-BfS colloquium was a by-invitation-only affair, and Microwave News was not invited. The BfS declined to provide a copy of Deltour’s PowerPoint presentation, as did Deltour and Schüz. Copies of most her 36 slides were however leaked to the Environmental Health Trust (EHT), which passed them on to me. They are available here.

With respect to the general conclusion that the incidence of brain tumors has been stable over many decades (slide 34), there are reasons to interpret this with caution.

  • From 1979 to 2016, incidence rates of brain tumors were “relatively stable” among those 59 years old or younger. But Deltour also stated that the rates among 60-69-year olds and 70-84-year olds were increasing
  • (slide 13). Most brain tumors develop in the older age groups, so this is where you are most likely to see changes in incidence trends.
  • Deltour states that the reliability of her analysis is dependent on the “completeness” of the cancer registry data (slide 34).

But at least for Sweden, the Nordic country with the largest population and the most cases of brain tumors, the cancer registry has been shown to be substantially incomplete. In fact, this was reported by a member of the Deltour-Schüz study team, Maria Feychting of the Karolinska Institute, not long ago (details here).

Rising Rates of GBM in Denmark and Sweden

Deltour had almost nothing to say about changes in the incidence of low-grade and high-grade brain tumors, notably glioblastoma multiforme (GBM; these are highly aggressive and soon lethal). She mentioned GBMs only once (slide 7), and the point she is making is hard to decipher.

This omission is surprising given the reports, published over the last few years, showing that high-grade tumors are becoming more common in at least two of the Nordic countries —Denmark and Sweden. At the same time, low-grade tumors are declining, leaving the total number of glioma essentially unchanged. This trend was first shown in England by Alasdair Philips in 2018, and confirmed by Frank de Vocht at the University of Bristol.

In a brief email exchange, Schüz told me that his team has incidence data by tumor subtype and that publishing these time trends “is one of our objectives.” He did not elaborate.

I shared Deltour’s PowerPoint with Philips and asked him to comment. Here’s what he told me:

“I think we all can all agree that the overall incidence of glioma is fairly stable. The important question now is: Is something in our environment promoting low-grade gliomas into high-grade GBMs? This appears to be happening in England as well as in other countries. We need to know if this is a real effect or whether it’s due to better imaging and/or changing definitions. That’s what IARC should be working on.”

Canadians Also See No Increase in Glioma

Also late last month, a group in Canada, led by Paul Villeneuve at Carleton University in Ottawa and Daniel Krewski of the University of Ottawa, published its own analysis of glioma trends in Canada between 1992 and 2015. They too found no consistency with the increases predicted by Hardell and the Interphone project, including its Canadian component.

In their paper, Villeneuve and Krewski cite Philips’s suggestion that cell phones may be causing more aggressive tumors to develop. They, like Deltour, do not present any glioma subtype data. I asked Villeneuve why. He replied that investigating those trends was outside the primary objective of the project. This is “worthy of further research,” he added.2

Villeneuve pointed out that he had submitted his paper for publication in 2019. It had been delayed until now, he said, because much of Canada had closed down due to the COVID pandemic.

Alumni of the Danish Cohort Study

It’s tempting to call the new IARC-BfS analysis the Revenge of the Danish Cohort Study.

Like the glioma trends project, the cohort study comes in three parts, and it too purports to show no brain tumor risks following the introduction of mobile phones. Schüz is the lead author of the two most recent updates, published in 2006 and 2011.

The first results of the cohort study came out in 2001. Christoffer Johansen, a member of the current Schüz-Deltour project, is the lead author. At the time, Johansen was at the Danish Cancer Society in Copenhagen, where Schüz and Deltour also used to work before moving to IARC about ten years ago.

Back in 2011, IARC’s own RF working group rejected the findings of the Danish Cohort Study in favor of those of Interphone and Hardell, which do show a cancer risk. This decision was largely due to the cohort study’s fundamentally flawed exposure assessment — those with the heaviest cell phone use are in the control group! (More here.)

IARC is the International Agency for Research on Cancer, an agency of the World Health Organization (WHO).


  1. IARC evaluations — spelled out in its Monographs — are considered the gold standard on the identification of cancer agents. The first volume, on a number of different chemicals, appeared in 1972. RF radiation is Volume 102. More about IARC Monographs here and more on IARC classifications here.  ↩
  2. In late 2019, Faith Davis of the University of Alberta, in Canada, reported that the incidence of GBM, though rising slowly over the last 20 years, has not jumped up in the U.S. and Canada, as it has in England. Story here.  ↩