The use of electricity is of great benefit to society in residential and occupational settings. Many of our daily routines would be severely disrupted were it not for electric power to control our indoor climate, store and prepare our food, clean our homes and clothing, and perform other tasks at home and at work. The ever-expanding use of electricity has not, however, come without risks: Most notable is the potential for shocks and burns from contact with energized electrical conductors. Recently, public concern has grown over the possibility that more subtle adverse health effects might exist as a result of exposure to the electric and magnetic fields (EMF) surrounding electric power transmission and distribution lines and the electric devices that have become common tools of the residence and workplace.
Numerous epidemiologic studies show an association between living near power lines and the incidence of some childhood cancers. In addition, several studies suggest that some adult cancers might be associated with occupations in which workers are exposed to elevated levels of power frequency (50-60 Hertz [Hz]) EMF. Most epidemiologic studies focus on the magnetic fields associated with 50 or 60 Hz power systems. The reported associations are generally weak and the suggested causality is highly uncertain. Reports of these studies in the popular news media, however, have excited a great deal of public concern, which in turn has been a driving force in setting research agendas for the study of extremely low-frequency (ELF) EMF by government agencies and private organizations.
Research on the biologic effects of exposure to ELF-EMF has been under way for more than two decades, and an extensive literature has accumulated. However, the scientific literature has not clearly demonstrated mechanisms by which power frequency EMF might induce changes that would lead to detrimental health effects. Research findings in this area are characterized by large uncertainties and, until recently, relatively few efforts have been made to replicate results in independent
laboratories. Furthermore, in cases where reproduction of experimental results has been attempted, the results have not been reproduced consistently. These uncertainties have led to a continuing controversy within the scientific community regarding the potential for 60 Hz EMF to harm human health and to a public outcry for resolving the uncertainties.
Because of the increasing public concerns, several workshops were held between 1990 and 1992 to review the state of knowledge and to discuss strategies for future research work to illuminate the issues. These workshops included participants from the Department of Energy (DOE), the National Institute of Environmental Health Sciences (NIEHS), the Environmental Protection Agency, the Electric Power Research Institute, public utilities, state governments, scientists, and others. The workshops established a basic framework for an enhanced national program in EMF research that was ultimately authorized by Congress in the Energy Policy Act of 1992 (Public Law 102-486).
Under Item 303, Section 2118, the act outlined a 5-year, $65 million program, that would involve a partnership of government and industry in determining whether environmental exposure to power frequency EMF poses a public health risk. The resulting Electric and Magnetic Fields Research and Public Information Dissemination (EMF-RAPID) program, has three primary components: The first is to determine whether exposure to EMF produced by the generation, transmission, and use of electric energy adversely affects human health. Second is to carry out research, development, and demonstration of technologies that would mitigate any adverse human health effects. Finally the program would provide for dissemination of information related to the possible human health effects of EMF exposure. The legislation established a National EMF Interagency Committee (IAC) and a National EMF Advisory Committee (NEMFAC) to guide the effort. In addition, the secretary of energy was directed to enter into an agreement with the National Academy of Sciences (NAS) to evaluate the research activities completed under the program and to report its finding to DOE, IAC, and NEMFAC.
In response to the directions of the Energy Policy Act of 1992 and a request from DOE, the National Research Council (NRC), the principal operating agency of the Academy, through its Board on Radiation Effects Research, established a committee of scientists and engineers to aid in its review of the activities conducted under the EMF-RAPID program. The NRC committee was also asked to review the research agenda and strategies adopted by DOE and NIEHS, as well as those suggested by other federal and nonfederal groups. More specifically, the NRC committee was asked to: review and evaluate the scientific and technical content of projects completed under the EMF-RAPID program; to review continuing research projects for scientific content and suitability to meet the goals of the EMF-RAPID research plan; to recommend modifications to the EMF-RAPID program, as appropriate, based on information the committee acquires about new research findings not available when the national research agenda was developed; and to assess the scientific and technical content, and recommend changes as necessary, for activities initiated under the EMF-RAPID program to promote the transfer of information derived from research projects.
The results of the NRC committee review and evaluations are to be reported to DOE and to IAC and NEMFAC annually. A final report, to be submitted at the conclusion of the EMF-RAPID program, will assess the research activities conducted under the act. This report is the first annual report concluded by the NRC committee under the EMF-RAPID program.
A great deal of care has gone into the development of the research strategy for the EMF-RAPID program, and no glaring omissions in the program can be identified. Previous research conducted on the biologic effects of exposure to EMF and published in the scientific literature has been criticized as being abundant with inconsistencies, containing large uncertainties, and not having been confirmed by other investigators. Another criticism is that experiments have
predominantly been conducted with exposures that are large relative to those encountered in the residential environment under normal conditions. Therefore, the research strategy for the EMF-RAPID program has as its major objectives the identification and quantification of appropriate environmental exposure parameters, the reproduction of several crucial biologic experiments, a commitment to reduce experimental uncertainty through the use of a team approach to experiment design, and the requirement of good laboratory practices in the research. An important component of the research strategy has been an effort to bring new researchers with excellent credentials for biologic research into this field of study. The research strategies seem consistent with the stated goals of the program.
RESEARCH STRATEGY AND AGENDA
The EMF-RAPID program must balance the desired depth and breadth within its limitations of time and budget. This has brought about a focus on research areas that are most critical to developing a data base that could be used in risk assessment studies. A major difficulty in assessing the ability of the research agenda to meet its risk assessment goal is the lack of a specific, defined methodology for undertaking risk assessment for any agent that interacts similarly to EMF exposure in contributing to adverse health effects. Without such a methodology, it is difficult to set a research agenda that will maximize the probability of success. Under the circumstances, the research strategy has been designed to focus initially on replication of experiments deemed important to identifying possible risk factors.
Among the major difficulties affecting the potential of the EMF-RAPID program to meet its goals are the methods of research administration and the limitations on time and budget. First, it is difficult to obtain definitive results on demand from a program of investigator-initiated basic research. Second, a significant amount of program time was devoted to setting up the machinery for initiating the coordinated program; this delayed the start of the actual research. The first research grants were awarded nearly two years after the program’ s congressional authorization.
At a minimum, this suggests that Congress should consider extending the program for 2 years, to 1999, to allow completion of the planned research.
The administration of the EMF-RAPID biologic research program by means of the National Institutes of Health’s (NIH) investigator-driven, grant-funded method of research funding also is a major difficulty. Although a highly refined method of funding investigator-initiated basic scientific research, it was not developed with the intent of organizing and funding a program of research with a specific aim. This also has contributed to a delay in meeting the program’s 5-year deadline.
Some areas of hypothetical importance to explaining a possible link between exposure to power frequency EMF and as yet unidentified adverse health effects are not included in the program; however, the program ’s emphasis on the health end point of cancer and on exposures to standard sinusoidal 60 Hz EMF is the only reasonable research agenda in view of cost limitations and the unlimited number of co-promotor and other feasible health end point effects, and the only way to ever bring the program to a conclusion that will satisfy most reasonable concerns.
Several studies have begun under the EMF-RAPID program in the areas of engineering, managed by DOE, and in vitro and in vivo biology, managed by NIEHS. The engineering studies focus on source characterization and exposure assessment for the power-frequency EMF to which people are commonly exposed. Electric and magnetic field management portions of the program are being postponed until later, when a better understanding of the environmental characteristics of EMF and their biologic significance might be available.
The in vitro studies focus on confirmation of earlier work on the effects of 60 Hz exposures on expression of the early-response genes, such as myc, fos and jun, and on the properties of membrane transport in mammalian cell systems. In vivo studies focus on the effects of EMF exposure as a promoter or copromoter of tumors and on the alteration of melatonin levels in animals exposed to EMF and on the likely consequences of observed changes in melatonin
concentrations. It must be recognized that when attempting to replicate previous experiments, one must follow the original protocol with obsessive precision because, there being no accepted theory of why one should see any effect at all, one has no idea as to which steps are truly essential and which can be modified or bypassed.
Six studies were scheduled to begin in fiscal year 1994 under the exposure assessment and source characterization portion of the program. Four of these are for the development of guidelines for measurement procedures and for establishment of a data base to make data that is collected readily available. The other two studies are for the initiation of a 5-year project of human exposure assessment and environmental surveys. It would have been preferable to initiate the latter two projects after the completion of the first four, but the time allocated by the program did not permit this delay. Exposure assessment and source characterization studies are scheduled in four more project areas in fiscal year 1995, but none was in progress at the time this report was prepared (July 1995).
The exposure assessment and source characterization is a large undertaking burdened with significant inefficiencies as a consequence of the schedule. Because it is not known which aspects of ELF-EMF exposure, if any, adversely affect human health, a prudent measurement program requires comprehensive measurements covering a wide range of the EMF attributes. To do otherwise risks failing to capture the relevant information. Even then, the EMF measurements taken might fail to capture the appropriate attribute or combination of attributes, and therefore it is possible that some of the accumulated data will be irrelevant. Consequently, it is difficult to understand the urgency of extensive statistical sampling projects to fill data bases that will be needed only if adverse health effects are confirmed.
Two objectives are identified for the electric and/or magnetic field management portion of the EMF-RAPID engineering research activity. First, there should be an evaluation of the costs, benefits, and effectiveness of options for managing EMF exposure, and second, if needed, new techniques
should be developed for management on the appropriate EMF components. Both are appropriate and attainable engineering efforts, once the relevant characteristics of exposures are understood.
The planned engineering research activity for quality assurance has just one objective and one project (funding for quality control efforts in a program the size of the EMF-RAPID program is clearly appropriate). The project identified is an expansion of a continuing effort currently funded by DOE outside the EMF-RAPID program.
In Vitro Studies
Fourteen projects were initially funded under the in vitro portion of the EMF-RAPID program. The primary focus of these projects is on the reproduction of seminal work in calcium ion transport, membrane transport, enhanced expression of early response genes, free-radical effects, and cellular promotion and copromotion by exposure to EMF. Confirmation of earlier results, or the lack on confirmation, should lead to firm conclusions about whether 60-Hz magnetic fields are biologically active in mammalian cells. If the results are positive they should be useful in establishing testable hypotheses for further studies.
In Vivo Studies
About one-third of the funds available in the initial grants of the EMF-RAPID program for the study of biologic response to 60 Hz magnetic field exposure was applied to the study of possible in vivo effects. Six studies begun in 1994 were split between exploring the role of 60 Hz magnetic fields on the modulation of melatonin and on the role of 60 Hz magnetic fields as a cocarcinogen in three tumor systems. This effort is focused on an extremely limited scope of exposure characteristics and biologic responses, and it must be recognized that if a component of EMF other than the putative 60 Hz sinusoidal character is biologically active or if the response is manifest in terms other than the particular end point under investigation, this set of studies might not detect possible effects of EMF exposure, and negative findings could be inconclusive.
Furthermore, the effort is so small that it does not provide for replication of results, as does the in vitro portion of the research program.
Because the program has only recently begun, just one project has been completed and provided to the NRC committee for review. That project, prepared under the public information dissemination portion of the EMF-RAPID program, was the development of Questions and Answers About Electric and Magnetic Fields Associated with the Use of Electric Power (DOE, NIEHS, 1995). The NRC review committee believes this is an excellent document for the audience intended. For the most part, the booklet provides factual, unbiased information in a language that is useful to a large segment of the population. However, in the process of simplifying concepts, several minor technical errors were introduced. It must be noted that these errors are not significant, should not mislead anyone, and are considered to be offset by the availability of information at a level that can be understood by the lay public. This effort to present information in a clear and concise manner is considered extremely important.
A major weakness in the ability to design an appropriate research agenda for the EMF-RAPID program is the lack of a defined methodology to be used for the risk assessment task to be fulfilled at the conclusion of the program. Existing risk assessment methodologies are developed to quantify the human health risk under low environmental exposures from a compound known to be carcinogenic at high doses. These methods are not suitable for EMF risk assessment because it is not clearly established that EMF is carcinogenic at any dose. Without a defined methodology, it is not clear how the studies in engineering and biology will fulfill the goal of supporting the risk assessment task of the EMF-RAPID program. This committee strongly recommends that the
Risk Assessment Working Group develop the process by which data will be incorporated into a formal risk analysis and to make that process known to the program managers to guide the research-planning effort.
The investigator-initiated grant process by which health effects research is funded by NIEHS can have severe consequences on the timely start of urgently needed research. This process was not designed to promote focused and directed research as outlined in the EMF-RAPID program. To use the system most effectively, and given the unique character of the ELF-EMF research agenda, it is recommended that a special study section be used to evaluate new proposals and competing renewals. The study section should include individuals with a broad and specific knowledge of EMF research. The special study section approach was used with good effect to initiate the NIEHS portion of the EMF-RAPID program. In addition, a funding mechanism should be included to allow for the rapid implementation of studies that seek to either replicate key findings or to test new hypotheses derived from continuing work. The selected use of cooperative agreements or supplementary applications is recommended to allow a more timely performance of highly focused studies.
The design of engineering studies suffers from a lack of knowledge of the relevant mechanism for the interaction of EMF with biologic systems. This knowledge is needed to provide efficient program direction. Investigators now must balance the need to characterize environmental electric and/or magnetic field exposures to guide studies in biology and epidemiology with the desire to know “all” about the characteristics of EMF. A sequential and conservative approach must be applied to identify the range of EMF parameters encountered in residential and occupational exposure and simultaneously to avoid large statistical surveys that might precisely quantify irrelevant parameters.
In the same manner that the program planning for engineering studies suffers from not knowing the biologically relevant field parameters, the planning of biologic studies suffers from the lack of information about the risk assessment technology to be used. The EMF-RAPID program also is limited in that it includes little effort to seek information on the effects of EMF exposures other than to sinusoidal 60 Hz magnetic fields. Moreover, the emphasis is almost exclusively on cancer as the end point. Effects from the combination of alternating current fields from power lines or electrical devices with the static components of the geomagnetic field, or from transients that involve relatively large and rapid changes in the electric or magnetic field, could be important in initiating biologic response. Consideration also should be given to such biologic end points as neurobehavior and reproduction and development.
A primary goal identified by the EMF-RAPID program is to examine techniques to mitigate risks from exposure to EMF. Within the context of the limited schedule, and given the lack of information about biologic effects, pursuing this goal seems premature. It is recommended that this task be delayed until the risk factors have been better defined.
Finally, the delays encountered in starting the program and the time constraints inherent in the grants process strongly argue for an extension of the sunset clause of the Energy Policy Act of 1992. Two more years are needed to ensure timely completion of the research projects still to begin under the EMF-RAPID program. We urge Congress to consider allowing an extension.
With any program of this complexity, there comes a time when it is necessary to determine that an adequate answer is at hand and that research should be curtailed. The EMF-RAPID program should include a formally structured administrative mechanism to conclude whether the data taken in toto support the concept that a significant risk from ELF-EMF does, or does not, exist. Most programs established to evaluate potential risks of exposure to environmental agents are difficult to terminate, given the interests of the individuals involved. The competing interests should be recognized and a method to integrate multiple pressures should be developed. This could be accomplished within the formalities of the risk assessment process, or it could be a separate process of review of the risk assessment.
The information booklet, Questions and Answers About Electric and Magnetic Fields Associated with the Use of Electric Power, is a commendable effort of exceptional value for providing information to the lay public. However, our review revealed several minor errors. We recognize that the booklet was subjected to numerous reviews and that the minor errors we detected should not mislead the lay reader. However, it is recommended that experts in engineering, physics, and biology should review subsequent booklets.
Although commendable, the booklet provided only a brief discussion of the results of in vitro and in vivo investigations of the effects of exposure to ELF-EMF. We recommend that another booklet expand the discussion to include laboratory studies. In addition to summarizing completed research, the booklet should discuss uncertainties, the origin of uncertainties, and their effects on the risk assessment process. This information should be prepared for the lay audience, but it should include a relatively complete listing of appropriate scientific literature for the more interested reader.