Real versus Simulated Mobile Phone Exposures in
Comments on Reverberation Chamber Exposure System
During the 1990s, I ran the Wireless Technology Research program, overseen by a U.S. government Interagency Working Group and funded through a trust organized by the wireless phone industry. In our original research agenda, long-term animal studies were contemplated, although they were later eliminated as the industry pulled funding. In the WTR program, we spent more than two years and $5M studying and evaluating different exposures systems so that the most rigorous exposure systems for predicting human risk could be used for our studies. The results of that work are published in the books whose cover pages are attached herewith, as well as in other presentations at professional meetings and special issues of journals throughout that time. The WTR exposure system work was front and center at every relevant toxicological meeting conducted through the 90s, so not a secret. Overall, we learned in the WTR work that it was important to be conveying information over the signals — voice or data — in order to achieve the ‘real-life’ modulation impact on biological triggers that are known. For example, to take this into account in the WTR exposure systems, we ran a tape recording of voice during exposure times in order to achieve a closer approximation of real-life use. We also learned that, if studying brain tumors, it was important to have a ‘head-only’ exposure system as opposed to a ‘whole body’ exposure system. We were able to achieve that type of exposure system for rats but found it to be not feasible for mice. Again, findings of rat studies using this approach are included in the books referenced as well as elsewhere. When the NTP study was being designed, it was baffling that the exposure system developed under the WTR was not carried forward. The WTR system was the most extensive and rigorous system available at the time. In fact, Niels Kuster who was one of your named exposure system consultants, was part of the working groups that developed the WTR systems and indeed tried to purchase the system at auction when the WTR disbanded in 1999. Thus, the value of the system was known as well as the rationale used to develop it. This lapse in using the appropriate exposure systems creates difficulties in interpreting the meaning of the NTP results. First, when the ‘whole-body’ is exposed as in the NTP study, there are a host of physiological compensations triggered in response to the exposures in cells, tissues, organs and organ-systems that are near impossible to quantify in terms of how they impact the outcomes being studied. This could be one of the reasons for the internal inconsistencies in the NTP study. The inconsistencies could well be the result of biological phenomena not measured in the study design and thus not interpretable as evidence of either effect or no-effect. Further, it appears that the exposure systems used in the NTP study did not employ the type of modulation that occurs with real mobile phone use — no information carried on the signals, no voice modulation, and no signal perturbations derived from other competitive signals in the environment which accrues in effect another, uncontrolled type of signal modulation. Taken together, the chance of triggering biological cascades could be exacerbated or limited by the system used. We know modulation to be the main trigger for bioactivity. See the attached paper for reference by Panagopoulos, Johansson and myself. Finally, this incomplete exposure system could be, and in fact is likely, accruing imprecision across the independent variable that would tend to bias results toward the null or underestimate the true risks. So, my main questions for the investigators are the following:
1. Given the shortcomings in the exposure system detailed above and expressed in the published literature prior to the designed of the study, what was the power of the NTP study to find statistically significant differences between exposed and unexposed in the study for each of the dependent variables studied?
2. Given the limitations that are derivative of those exposure-outcome specific power calculations, what admonitions in interpretation do the investigators prescribe?
Comments on Peer Review of NTP Findings in Rats and Mice
It is important to take into account the purpose of doing a study like this — I assume the purpose is to predict possible risks of tumors in humans who use cell phones. The need for this study flowed from two flaws in the system propagated through U.S. government agencies as regards cell phone safety: The first is the lapse in judgement that resulted in cell phones making into the marketplace without the benefit of pre-market testing. Had the findings presented in the NTP study been found in the context of pre-market testing, these questions that are being addressed now would have been able to have been addressed, not in the context of a wide-spread, after-the-fact human experiment, but as normal scientific iteration that would have either resulted in more refined studies ahead of deployment into commerce, or a prescription for technological changes in cell phone design that would have mitigated risks, or both. The second lapse in judgement was the allowance by the U.S. government’s Interagency Working Group that oversaw the work of the WTR to pull back wireless industry funding for these long-term bioassays that were originally prescribed to be done under the WTR program. Had those studies been allowed to be completed, the NTP study would now be looked at in the context of scientific corroboration and not a study of first impression. Given the above lapses, the NTP investigators were put in a no-win political situation as they deployed this study. It was not possible to design a pre-market study because the scenario was no longer premarket, and it was not possible to design a study that would have direct and long-standing relevance to the actual risks to cell phone users because the exposures over time have been a rapidly moving target. Further, given that a basic underlying premise of these types of toxicological studies is that, where there is a risk to be found, cause induces effect, it is necessary to design the study with some knowledge of mechanisms of harm that are operating. And, it is possible that different iterations of the technology could have different variations on mechanism of harm. Attached is a paper that addresses such issues.
Finally, the quantitative measures of exposure used in the analyses appear to focus primarily on thermal effects and not non-thermal effects. See attached paper on the ramifications of such a limitation. My main questions for the investigators are the following:
1. Given the changes in wireless technology signaling and devices over the past two decades — the fifth generation of signaling is now being deployed suggesting that the technology and resultant exposures in people are changing every 4 to 5 years — what admonitions in interpretation do the investigators prescribe as per the relevance of these findings to cell phones of yesterday and of today?
2. What mechanisms of harm were in the thinking of the NTP at the time the study was designed and initiated?
3. Given the above shortcomings, what admonitions in interpretation do the investigators prescribe?
George L. Carlo
Science and Public Policy Institute
*Get the full paper at the link below and add to the conversation on this topic in the comments, all input helps lead the way to insight.
Comments on Reverberation Chamber Exposure System
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