Friday, April 18, 2014
Comments on "Do people understand IARC’s 2B categorization
of RF fields from cell phones?"
In May, 2011, a working group composed of 31 experts on
electromagnetic field (EMF) radiation convened by the International Agency for
Research on Cancer (IARC) of the World Health Organization (WHO) reported on
the results of an extensive review of the health effects research. The
committee concluded that radio frequency energy is a Group 2B carcinogen, which means this type of
electromagnetic radiation is possibly cancer-causing in humans.
In arriving at this conclusion, the working group relied heavily
on the results of the Interphone Study, a 13-nation study sponsored by the WHO,
and a series of studies conducted by Dr. Lennart Hardell in Sweden.
The journal Bioelectromagnetics recently
published a "letter to the editor" which questions the 2B
classification (1). Although the letter makes a few valid points — most
laypersons don’t understand the meaning of “possibly carcinogenic” or “40% risk
increase” — the authors' intent seems to be to undermine the credibility of the
IARC working group’s review of the health effects of exposure to radio
frequency energy. In his science blog on mobile phone radiation and
health, Dr. Dariusz Leszczynski has called this letter, "A travesty of science."
The letter is a polemic which argues that the IARC working group
should have been composed of members “who are not involved in the EMF field” to
avoid conflicts of interest. The authors recommend that scientific review
panels be composed of individuals who have no expertise in the specific field
of study under review — a rather odd solution to this age-old problem.
Ironically, the authors cite Dr. Ahlbom’s work to dismiss Dr.
Hardell’s research; yet, Dr. Ahlbom was the scientist with the undisclosed
conflict of interest. Dr. Ahlbom opted not to attend the IARC working group
meeting after WHO informed him he could not chair the epidemiology subgroup
after Mona Nilsson, a Swedish investigative journalist “outed” him for his
undisclosed associations with the cellular industry.
The authors failed to discuss the results published in Appendix
2 of the major Interphone study paper which finds that after correcting for one
of the study biases the 40% risk increase for the heavy cellphone use group
becomes an 80% risk increase.
The authors also failed to mention the peer-reviewed research
that has been published since the IARC working group was convened in 2011.
These more recent studies provide greater evidence of the carcinogenicity of
cell phone radiation.
Why are the authors of this paper so motivated to dismiss the
science and the consensus of the 30-member IARC working group (not counting the
member from our National Cancer Institute who walked out of the meeting in
protest)? One must wonder whether the authors disclosed all of their
conflicts of interests?
***
(1) Wiedemann PM, Boerner FU, Repacholi MH. Do people understand
IARC’s 2B categorization of RF fields from cell phones? Bioelectromagnetics.
2014 Apr 15. doi: 10.1002/bem.21851. [Epub ahead of print]
Abstract
In May 2011, the International Agency on Cancer in Research
(IARC) issued an official statement concluding that cell phone usage was
“possibly carcinogenic to humans.” There have been considerable doubts that
non-experts and experts alike fully understood what IARC’s categorization
actually meant, as “possibly carcinogenic” can be interpreted in many ways. The
present study is based on an online survey indicating that both the
characterization of the probability of carcinogenicity, as well as the
description of the risk increase given in the IARC press release, was mostly
misunderstood by study participants. Respondents also greatly overestimated the
magnitude of the potential risk. Our study results showed that IARC needs to
improve their scientific communications.
Excerpts
Using Survey Monkey (Palo Alto, CA), an online survey consisting
of 13 questions was conducted in April 2012. Information about this on-going
survey and the opportunity to participate was made available to all 27,000
students of the University of Innsbruck in Austria. A total of 2,013 students
with a mean age of 24.5 years participated, with 66% of the respondents being
female and 34% male. The students were from a wide variety of academic
disciplines, and participation was anonymous and voluntary. The survey used
parts of the original IARC [2011] press release as stimulus material.
Participants were instructed to read the text from the original IARC press
release: “The WHO/International Agency for Research on Cancer (IARC) has
classified radiofrequency electromagnetic fields as possibly
carcinogenic to humans (Group 2B), based on an increased risk forglioma,
a malignant type of brain cancer associated with wireless phone use. The IARC
[2011] did not quantitate the risk; however, one study of past cell phone use
(up to the year 2004), showed a 40% increased risk for gliomas in the highest
category of heavy users (using their phones for 30?min per day over a 10-year
period).”
… We asked, “What does a 40% risk increase mean?” and “How many
additional cases will suffer from cancer?” Respondents could choose between
five answers (1) 1 in 4, (2) 4 in 10, (3) 4 in 100, (4) 1 in 40, and (5) a
number >0. As shown in Figure 2, the majority of respondents interpreted a
40% risk increase as 4 in 10. The correct answer depends on the baseline, that
is, the normal brain cancer incidence in the population studied. Since IARC
does not present any baseline information, a number >0, is the only
meaningful answer to the information provided from Text 1. Figure 2 shows that only
about 10% of the respondents picked the correct category (N?>?0).
…The relative risk statement should be strengthened by
information on the incidence rate expressed as the number of new cases per unit
of population per year. Given that the incidence of adult glioma is
approximately 4.7 per 100,000 persons a year, a 40% increase in risk would mean
an additional 1.9 cases of glioma per 100,000 people each year.
… A good 2B narrative should address the issues of who, why and
what follows from the 2B classification. The “who” refers to the need to
characterize the authors of the classification. The key issue here is that the
credibility of the classification of RF fields depends on trust in the process
and in the people who conducted the classification. There should be some
concern that there are working group members who are the very researchers
assessing the quality of their own studies. This would be a reason for people
to question the credibility of the classification. A solution to this
credibility issue for IARC could be to more thoroughly determine and account
for the various potential conflicts of interest and to search for potential
working group members without such conflicts. An example could be to select
working group members who are not involved in the EMF field to conduct a truly
independent review.
… The Interphone Study noted that: “Overall, no increase in risk
of glioma or meningioma was observed with use of mobile phones. There were
suggestions of an increased risk of glioma at the highest exposure levels, but
biases and error prevent a causal interpretation.” IARC claims this is a
positive study according to their definition when the study authors do not.
This is a credibility issue. This existing ambiguity in the 2B-evidence base
opens IARC’s classification to contrasting interpretations and opinions. From a
communications standpoint, it is necessary to clearly and transparently inform
about the pro and contra arguments for the classification based on the selected
evidence. The other positive study [2009] was clearly demonstrated [2009] to be
an outlier compared with the majority of other epidemiological studies. While
IARC’s definition of 2B was technically complied with, because two epidemiology
studies showed positive results, there is considerable doubt about the
interpretation of what is a positive effect.
… The central message of the present study is that IARC needs to
improve their current scientific communications, and in doing so, keep within
its mandate vis-à-vis its parent WHO. We believe that focusing, for example, on
adding a quantitative explanation to verbal probability expressions or using
comparisons and narratives could help to ensure that everyone understands the
state of the scientific findings and their underlying uncertainty. This may
also enable all parties to draw the necessary conclusions for future health
policy activities.
Conflicts
of interest: The Science Forum EMF, founded by Peter Wiedemann, is a project of
the Institute for Technology Assessment and Systems Analysis (ITAS) at the
Karlsruhe Institute of Technology (KIT), a member of the Helmholtz Association
of German Research Centres.
The World Health Organization’s overall risk assessment of all health outcomes for mobile communication technologies has started and is expected to be completed by the end of 2014.
