The German RF research institute, Forschungsgemeinschaft Funk (FGF), in cooperation with COST281 and the German state of Baden-Württemberg sponsored an international workshop for about 40 scientists, government officials and industry observers on Nov. 25–27 at a conference center near Löwenstein, Germany, to review key in vitro evidence for exposure effects of RF EMF from mobile phones on the incidence of human cancer or genetic defects.
Gerd Friedrich, FGF, Bonn, and colleagues explained that the workshop, titled “Genetic and Cytogenetic Aspects of RF Field Interaction,” also was developed so that experts could consider “whether existing limits of maximum exposure really guarantee safe use of modern techniques of communication,” and whether there may be so-called “non thermal” genetic effects from exposure below intensities at which there is a measurable rise in body temperature.
Invited speakers included Isabel LaGroye, PIOM, University of Bordeaux, France; Vijayalaxmi, University of Texas Health Science Center, San Antonio, Texas, USA; Rafi Korenstein, Tel Aviv University, Jerusalem, Israel; Maria Rosaria Scarfi, ICEmB, University of Naples, Italy; Dariusz Leszczynski, STUK, Helsinki, Finland; Luc Verschaeve, Vito, Boeretang, Belgium; Myrtill Simko, University of Rostock, Germany; Roland Glaser, Humboldt University, Berlin, and Kenneth Foster, University of Pennsylvania, USA.
Participants looked at strengths and limitations of assays used to identify genetic damage, then applied some of this information to the interpretation of key findings of RF exposure effects reported by a small number of research groups. These include:
- DNA strand breaks and other genetic damage
- “Nonthermal genomic instability”
- Micronucleus induction reported
- Synergistic effects of RF plus another environmental factor
- RF-induced gene expression
Dr. Oskar Grözinger, chief of the radiation protection section of the Ministry of Environment and Transport for Baden-Württemberg, opened the workshop with general remarks on policy and research needs. He said that research can help to answer public resistance and fear that is leading to delays and even cancellation of base station siting in Germany. Public fear has also delayed progress on next generation technologies such as UMTS. Some mobile radio network operators have begun to in-vest in other areas, he added.
Grözinger explained that lack of information can add to fear, and at present “there is a huge public interest in knowing about existing and planned site of mobile radio transmitters.”
COST281 and WHO Disagree on Need for Base Station Epidemiologic Study
At the Löwenstein workshop, a disagreement emerged between the World Health Organization (WHO) and the European Union’s COST281 program over whether epidemiologic studies near mobile phone base stations are needed. Dr. Lawrence Goldstein of the WHO International EMF Project, Geneva, began his presentation by repeating the organization’s definition of health, which mentions a person’s “complete mental, physical and social well being,” not merely the absence of disease.
Recognizing that wireless technologies are becoming ever more sophisticated, and numbers of juvenile mobile phone users and base stations are increasing, WHO EMF Project staff believe that epidemiologic studies are needed to determine whether base stations pose a health risk—from cancer to sleep disturbances and headaches— among residents, Goldstein said. WHO staff believe that personal dosimetry and monitoring can be developed successfully for mobile base station epidemiology, he added. (For more views from WHO, see story page 9).
Further, WHO staff are considering whether children might represent a sensitive subpopulation, and WHO plans to devote some attention to this question in the coming years as part of its “Health Environments for Children” initiative. Goldstein said that the WHO International EMF Project plans to explore, among other questions, whether children use mobile phones in a different way than adults.
Finally, Goldstein announced that WHO will sponsor a workshop on Feb. 24–26, 2003, in Luxembourg, on the use of the Precautionary Principle as a response to uncertainty in scientific knowledge, with particular attention to possible health effects of extremely-low frequency (ELF) and RF EMF, and discussion of an appropriate public health response.
But Norbert Leitgeb of the University of Graz, Austria, secretary of the European Union’s (EU) Cooperation in Science and Technology project COST281, who spoke immediately after Goldstein, reported that at the COST281 meeting at the Royal Society in London on Nov. 10–11, members decided to oppose base station epidemiologic studies. For several reasons, COST281 will recommend to the European Union that such research is not needed, Leitgeb said. Reasons have been summarized in a formal statement (see story on page 9) on the COST281 Web site at www.cost281.org/over.php this month.
The abstract book from the COST281 and FGF-sponsored meeting in Löwenstein is available in the “Documents Section” of the COST281 Web site, www.cost281.org/index.php
Larger Role for Biophysics in Risk Assessment?
Also at the Löwenstein workshop, Kenneth R. Foster of the University of Pennsylvania pointed out that some of the major questions in the mobile telephone-health effects debate were addressed decades ago by physics research, but are still ignored in current discussion.
One long-standing issue with both RF and with ELF fields has been the lack of a credible mechanism for toxic effects at typical exposure levels. The public health community usually gives little weight to such biophysical considerations when evaluating epidemiologic evidence about EM fields, Foster said. Recent conclusions of the California Department of Health Services’ EMF Program offer a good example of this approach.
Foster agreed that epidemiologic results may always carry more weight in risk assessment but argued that there is a valuable role for biophysicists to play in the science related to the health issue. At least tentative hypotheses are needed to plan experiments and interpret data. But the bioeffects literature is filled with inconsistent experimental results, much clearly preliminary, and with speculations about possible mechanisms.
“Any correct biophysical theory must take into account both the strength of the interaction with the field and the dynamics of the biological system, including the presence of thermal noise and dissipative mechanisms,” said Foster.
“When this is done, there are no established mechanisms other than thermal by which RF fields at typical environmental levels can produce observable biological effects, let alone effects that might be related to genetic damage.” For example, it has been established for decades that a physical structure acted on by a field will exhibit a finite response time, which imparts a lowpass response; that is, the system exhibits decreasing sensitivity to fields at higher frequencies.
Also, thermal energy present in a living biological system is agitating molecules at such a rate that far exceeds any effect of RF fields at plausible exposure levels. Foster said. Calculations typically indicate that the difference between the amount of energy that you can couple into a molecule by RF fields, and background thermal energy, is many orders of magnitude. Nevertheless, the strength of interaction required to overcome such thermal thresholds is rarely mentioned in the recent crop of theories about possible mechanisms for RF bioeffects. A lot of discussion overlooks the fact that you cannot add significant amounts of energy to microscopic objects with radio-frequency energy at plausible exposure levels, because of rapid dissipation of energy. As a result, speculation abounds about implausible mechanisms for RF effects. People ask, “Which is wrong, the biology or the physics?” But it can be very hard to interpret experimental evidence after the fact. In most such cases, the initial data were somehow interpreted incorrectly or were artifacts, Foster believes.
Like others in recent years, Foster called for the EMF research community to be more careful in evaluating preliminary data. “We need the scientific community not to assume that some reported change in a biological parameter after RF exposure is an effect of the fields. Journals need to be more careful in accepting reports of one-shot experiments or studies that rely extensively on post-hoc interpretation of preliminary data. At the minimum, editors should require investigators to repeat their experiments before submitting the results for publication and reduce the amount of post hoc interpretation of their data.