Electric power is used all over the world. In the United States, the generation, transmission, and use of electric energy is associated with the production of weak electric and magnetic fields (EMF) which oscillate 60 times per second (power-line frequency). These fields are a fact of daily life: they are emitted by power lines, transformers, service wires, and electrical panels as well as by home appliances (such as electric blankets, waterbeds, clocks, shavers, and televisions). Electricity has been used, to great advantage, for 100 years without society being aware of any adverse health effect, other than thermal injury and electrocution.
Thus, when Wertheimer and Leeper reported in 1979 that children living near power lines had an increased risk for developing cancer, the concern was immediate, and a controversial area of research was born. Yet, despite a multitude of studies, there remains considerable debate over what, if any, health effects result from exposure to EMF. There is still no clear answer to the question, "Can exposure to electric and magnetic fields resulting from the production, distribution, and use of electricity promote cancer or initiate other health problems?"
Faced with growing concern on the part of the public about whether EMF might be adverse to human health, Congress mandated the Electric and Magnetic Fields Research and Public Information Dissemination (EMFRAPID) Program in the 1992 Energy Policy Act, Public Law 102-104. The National Institute of Environmental Health Sciences (NIEHS) and the Department of Energy (DOE) were given the responsibility for directing and managing the program. This five-year effort, jointly funded by Federal and matching private funds, was designed to improve our understanding of the potential adverse health effects of exposure to extremely low frequency (ELF) EMF, especially those produced by the generation, transmission, and use of electricity. The EMFRAPID Program sought to explain any links between EMF exposures and human health and any special conditions under which cause-effect relationships might occur. The 1992 Energy Policy Act requires a report from the NIEHS Director outlining the possible human health risks upon completion of the Program.
As part of its strategy for preparation of the report, the NIEHS developed a novel program that brought together diverse areas of science. The program involved large numbers of research scientists with diverse expertise both within and outside the EMF research field. With the aid of the National EMF Advisory Committee and the EMF Interagency Committee, the NIEHS used its existing peer-review grants process, worked with the DOE to characterize and improve methods for measuring exposure, and conducted a two-year study of carcinogenicity in experimental animals.
As the program entered its last two years, the NIEHS enacted a two-tiered process for collecting and evaluating information for the Director's report: Science Review Symposia were held in which open public debate was encouraged with regard to key research findings on EMF; and a rigorous, multi-disciplinary, scientific assessment of available data on the health effects of EMF was conducted by a Working Group. This publication represents the output of the working Group. The process was publicly open, scholarly, objective, and sufficiently flexible to accommodate the changing face of EMF research and public health concerns.
In the first step of the process, with the aid of their advisory committees and scientists in the field, the NIEHS opened the review on the interaction of ELF EMF with biological systems by holding the first Science Review Symposium in Durham, NC, in March 1997. The participants addressed specific questions concerning the mechanisms governing the interactions of ELF EMF with biological systems in vitro and using biophysical theories. The participants included engineers, molecular biologists, toxicologists, physiologists, epidemiologists, mathematicians, and physicists, some specialized in EMF and others from different fields. The report of the discussions has been published (Portier & Wolfe, 1997). Two further symposia were held, one on the epidemiology of exposure to ELF EMF in San Antonio, Texas, in January 1998 (Portier & Wolfe, 1998a), and the other on in-vivo/clinical investigations in Phoenix, Arizona, in April 1998 (Portier & Wolfe, 1998b). Through this series of three symposia, the NIEHS identified the key aspects of science that should be used in making any decision about health effects.
In the second step of the process, a Working Group was selected carefully after screening by the NIEHS and discussions with its two standing external advisory boards. The members of the Group represented a wide range of scientific disciplines, with and without a particular interest in EMF. During a nine-day working session in Brooklyn Park, Minnesota, they conducted a careful, thorough scientific review of all of the evidence related to health effects associated with exposure to ELF EMF. Certain members of the Group developed drafts in advance of the meeting to be used as the basis for discussion on specific aspects of research on ELF EMF. At the meeting, subgroups read, modified, and rewrote the drafts to reflect the consensus of the Group.
The attached document is the report of the Working Group on the
health effects of exposure to ELF EMF. The evaluations of carcinogenicity
were reached following the guidelines used in the International
Agency for Research on Cancer (IARC) Monographs on the Evaluation
of the Carcinogenic Risk of Chemicals to Humans, with minor
modifications (see footnotes, Appendix A). Evaluations of other
health end-points followed the same criteria, with minor exceptions
relating to final evaluations (see footnotes, Appendix A).