Monday, April 21, 2014

No link between mobile phone radiation and cancer, says Padma awardee doctor

A news article published today in The Indian Express is titled, "No link between mobile phone radiation and cancer, says Padma awardee doctor" (; article reprinted below). 

Dr Siddhartha Mukherjee, a Pulitzer Prize-winning professor of medicine from Columbia University, called on the World Health Organization to remove cellphone radiation from the list of carcinogens in a lecture he presented in New Delhi.

Why am I not surprised? 

Because on April 13, 2011, shortly before the International Agency for Research on Cancer (IARC) declared that radio frequency energy, including cell phone radiation, is "possibly carcinogenic" in humans, Dr. Mukherjee published an article in the New York Times Magazine, "Do Cellphones Cause Brain Cancer?" (  He argued that "not a single trial or test that has attributed carcinogenic potential has been free of problems," and labeling something "potentially cancer-causing" is "like crying 'wolf' about cancer."

IARC uses five categories to classify the carcinogenic risk of thousands of agents, mixtures, and exposures:

  • Group 1: carcinogenic to humans.
  • Group 2A: probably carcinogenic to humans.
  • Group 2B: possibly carcinogenic to humans.
  • Group 3: not classifiable as to carcinogenicity in humans.
  • Group 4: probably not carcinogenic to humans. (Wikipedia,
Apparently, Dr. Mukherjee would like IARC to use only Groups 1 and 4 as he does not like "shades of gray." He forgets that the absence of conclusive evidence of harm is not evidence of safety. Perhaps we should stop warning people about ultraviolet radiation as this exposure is classified in Group 2A? Whatever happened to the "better safe than sorry message"?

In his recent lecture, he asserted, "But I am willing to revise this assessment if there is additional data available" to which my reply is "read the peer-reviewed research published since you wrote your article in 2011." We have additional evidence of carcinogenicity in humans. In fact, two peer-reviewed papers have been published making the case for a stronger classification for cell phone radiation's carcinogenicity.
On April 21, 2011, I wrote Dr. Mukherjee the letter which appears below. I argued the case why my colleagues and I believe that cell phone radiation is carcinogenic.  I have yet to receive a reply.

By the way, I have no conflicts of interest; Dr. Muhkerjee's recent lecture was co-sponsored by the cellphone operators association of India.

No link between mobile phone radiation and cancer, says Padma awardee doctor

The Indian Express (New Delhi), Apr 21, 2014

Photo caption: Pulitzer award winning India-born oncologist Dr Siddhartha Mukherjee addresses a press conference in the capital on Monday.

Summary: Calls for revision of World Health Organization’s list of carcinogens, says not enough data to establish the link.

India-born oncologist Dr Siddhartha Mukherjee on Monday urged World Health Organization to remove cellphone radiation from the list of carcinogens on the ground that the “preponderance of evidence suggests there is no link” between radiation from mobile phones and cancer. In an event sponsored by COAI (formerly known as Cellphone Operators Association of India), India International Centre and Open Health Systems Laboratory,  he delivered a lecture making a strong case for the revision.

Dr Mukherjee, author of the Pulitzer winning book The Emperor of All Maladies: A Biography of Cancer that was published in 2010, is currently in India to accept the Padmashree award. He is an assistant professor of medicine at Columbia University and a staff physician at Columbia University Medical Center in New York City.

In a recent article in The New York Times he had argued that the drastic increase in cellphone usage does not mirror incidence of brain cancer, neither is the radiation emitted by cellphones of the nature that can directly damage DNA. He also termed as “loose” WHO’s definition of “possible carcinogens”, some of which “defies logic” in their proclivity to be more conservative.
However, he says, “The last word has not been said on the matter of cellphone radiation and cancer. The interphone trials (that sought to examine the link) have a serious recall bias — people did not always correctly recall the extent of their cellphone usage. There is a need to examine how radiation of that wavelength can be carcinogenic. I would ask WHO to downgrade cellphone radiation in the list of carcinogens, which includes coffee. But I am willing to revise this assessment if there is additional data available.”

But he says there is not enough data to make a similar claim about radiation emitted by cellphone towers ...

April 21, 2011

Siddhartha Mukherjee, M.D., Ph.D.
Columbia University
Herbert Irving Cancer Research Center (Audubon III )
Room 603 1130 St. Nicholas Avenue
New York, NY 10032

Dear Professor Mukherjee:

First, I would like to congratulate you on your Pulitzer Prize. I look forward to reading your book.

I am writing you about your recent New York Times magazine article and NPR interview about cell phone radiation and brain tumor risk. Although I agree that epidemiologic research does not yield conclusive evidence, my colleagues and I have carefully read and analysed this research and conclude that the evidence is highly suggestive of increased brain tumor risk due to prolonged cell phone use.

My colleagues and I published a meta-analysis of 23 case-control studies (Myung, SK, Ju W, McDonnell DD, Lee YJ, Kazinets G, Cheng C-T, Moskowitz JM. Mobile phone use and risk of tumors: A meta-analysis. Journal of Clinical Oncology. 2009. 27(33):5565-5572). Although overall we found no evidence of increased tumor risk (including brain, eye, facial nerve, salivary gland, NHL), in our opinion it is a mistake to simply look at the “weight of the evidence” as many scientific committees and government health agencies have done, because not all of the evidence warrants equal weight. In our meta-analysis, cell phone use was associated with significantly increased tumor risk in the high quality or non-industry-funded studies, and significantly associated with decreased tumor risk in the low quality or industry-funded studies. The latter findings were most likely attributable to bias. Moreover, we found that 10 or more years of cell phone use was associated with significantly increased brain tumor risk. Another recent review obtained similar results (Khurana VG, Teo C, Kundi M, Hardell L, Carlberg M. Cell phones and brain tumors: a review including the long-term epidemiologic data. Surgical Neurology. 2009. 72(3):205-14.)

Since these two review papers were published, pooled results from the Interphone study were published from data collected in 13 nations between 2000 and 2004 (Interphone Study Group. Brain tumour risk in relation to mobile telephone use: Results of the INTERPHONE international case-control study. International Journal of Epidemiology. 2010. 39(3):675-694). Like many other epidemiologic studies, most participants in Interphone hardly used cell phones. In fact, the typical user had fewer than 100 hours of lifetime use. Furthermore, as you know brain tumors can take decades to develop so it’s unrealistic to expect to see increased tumor risk in the short term. The typical user in the Interphone study had their phones for about five years.

We agree that the quality of the epidemiologic research has been problematic, and that one cannot draw causal inferences from case-control studies. The Interphone study had numerous problems which have been discussed in the literature (Morgan, LL. Estimating the risk of brain tumors from cellphone use: Published case-control studies. Pathophysiology. 2009. 16(2-3):137-147). However, most of these biases work against finding increased tumor risk. 

Nonetheless, the study found increased risk of glioma in the highest decile of use group (i.e., lifetime cell phone use of 1,640 or more hours). This finding held up in 44 sensitivity analyses that controlled for potential study biases including the concern that some glioma patients may have exaggerated their cell phone use. (Also, a separate methods study indicated that recall bias was not differential for cases and controls.)

The final analyses reported in the second appendix to the Interphone study corrected for what was likely the most important study bias—participation bias. These analyses found a “dose-response relationship”—increased glioma risk with increasing number of years of cell phone use. Among those who used cell phones 10 or more years, Interphone found more than a doubling of glioma risk compared to cell phone users of less than 2 years. These results were similar to those found in a study conducted by Lennart Hardell and colleagues in Sweden. (In these analyses, the risk estimate for the highest decile of use group increased from 1.40 reported in Table 2 to 1.80.)

Three Interphone study investigators including the lead investigator, Elisabeth Cardis, along with Siegal Sadetzki and Bruce Armstrong, have recently called for precautionary health warnings. About a dozen nations have issued warnings to limit children’s cell phone use or to keep cell phones a safe distance from the body, especially the head and genitals. Typical recommendations include use of a wired headset, speakerphone or text and not use phones in locations with weak signals or in moving vehicles.

In addition to the epidemiologic evidence for tumor risk, there is considerable evidence from animal and cellular studies of biologic reactivity to cell phone radiation. Here, too, the evidence is inconsistent, but according to a review by Henry Lai, the research conducted independent of industry funding was far more likely to find harmful effects than industry-funded studies.

The U.S. government needs to cultivate and fund a scientific community that operates independent of industry for us to develop an unbiased, scientific knowledge base that can be used to develop policies that minimize population health risks from the adoption of EMF technologies. A $1 per year fee on cell phones would generate $300 million annually for this work.

Although brain tumors are rare and the research on cell phone radiation is not yet conclusive, with more than 300 million cell phones in use in the U.S. we believe it is imprudent from a public health standpoint to wait before issuing precautionary health recommendations. At a minimum, precautionary principle actions are immediately warranted.

Please feel free to call me if you would like to discuss these issues.

Best regards,

Joel M. Moskowitz, Ph.D.

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]


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.


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 for glioma, 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.