Microwave Exposure: Safeguarding Public Health in the Absence of National Standards
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H. A. KUES, P. E. MAZIK, AND J. C. MONAHAN Microwave Exposure: Safeguarding Public Health in the Absence of National Standards Henry A. Kues, Phyllis E. Mazik, and John C. Monahan The lack of a national safety standard for exposure to electromagnetic radiation has generated considerable public concern and a plethora of court cases. The involvement of the Applied Physics Laboratory in this arena began in the mid-1960s following disclosure of Soviet irradiation of the U.S. embassy in Moscow, and over the years has included measurements, research, education, and assistance to governments around the world. This article describes a recent case in which the scientific expertise and knowledge developed at the Laboratory were used to assist a local government. It presents one city’s attempt to deal with health concerns associated with electromag- netic exposure by endeavoring to protect and educate the public while allowing for the development of beneficial technologies. (Keywords: Antenna ordinance, Electromagnetic radiation, Radio frequency protection guidelines, Telecommunications.) INTRODUCTION Frequently, scientists and engineers at The Johns case-by-case basis. This article describes one such con- Hopkins University are asked to provide advice in their sulting relationship. The case is representative of the field of expertise to public organizations, scientific increasing need for research to provide the appropriate panels, and local and national governments. Public scientific base necessary to support a national standard service has long been the mission of the University, and for exposure to electromagnetic radiation. staff members at APL, as part of the University, support During the last half century, use of electromagnetic this role regularly. In fact, the Laboratory’s Mission radiation has increased tremendously, especially the Statement includes “. public service through educa- portion of the electromagnetic spectrum commonly tion, research, and the application of knowledge to called radio frequency (RF) radiation that includes the human affairs.”1 Laboratory staff members are also microwave region (Fig. 1). To the general public, the asked to provide individual consulting services, re- proliferation of military, industrial, and consumer appli- quests for which are reviewed by the Laboratory on a cations of RF radiation are evident in everyday life— 288 JOHNS HOPKINS APL TECHNICAL DIGEST, VOLUME 18, NUMBER 2 (1997) MICROWAVE EXPOSURE: SAFEGUARDING PUBLIC HEALTH Nonionizing radiation Ionizing radiation ELF, VF Radio frequencies Infrared UV X rays, g rays AM radio: 535–1605 kHz Light CB radio: 27 MHz Cordless phones: 49 MHz TV Ch 2–6: 54–88 MHz FM radio: 88–108 MHz Marine radio: 160 MHz TV Ch 7–13: 174–216 MHz TV UHF Ch 14–69: 470–800 MHz Cellular radio, specialized mobile radio, paging: 806–946 MHz Antitheft devices: 10–20 kHz and/or 915 MHz Microwave ovens: 915 and 2450 MHz Personal communication services: 1800–2200 MHz Intrusion alarms/door openers: 10.5 GHz Microwave radio: 1–40 GHz Satellite communications: 100 MHz–275 GHz 103 106 109 1012 1015 1018 60 Hz 1 kHz 1 MHz 1 GHz Frequency (Hz) Figure 1. Diagram of the electromagnetic spectrum (ELF = extremely low frequency, VF = voice frequency). from numerous radar sites, industrial and commercial BACKGROUND use of microwave ovens, radio and television stations, In the mid-1960s, investigation of the effects of advanced medical devices, and computers, to the in- microwave radiation exposure began at APL with creasing use of communication systems such as cellular Project Pandora.2 At that time, a multidisciplinary telephones and satellite–Earth stations. The societal team of investigators, including Eugene V. Byron, an benefits from these technological advances and their numerous applications are self-evident. However, the electrical engineer at the Laboratory, was assembled by increased use of new technologies results in a complex the Department of Defense and tasked by the Depart- electromagnetic environment, and, ultimately, an in- ment of State to evaluate the exposure of personnel at crease in exposure of the population to RF radiation. the U.S. embassy in Moscow, following concerns raised Increased exposure to RF or microwave radiation and by the disclosure of routine Soviet irradiation of the the potential for adverse health effects due to exposure embassy building. Subsequently, Laboratory employee have raised concerns of the medical and scientific Robert C. Mallalieu performed a retrospective study for communities, government agencies, and the public. the Department of State, encompassing the period Unfortunately, with ever-tightening federal budget con- from January 1966 to February 1977, which provided straints, there is a lack of funding for the research a model of the microwave intensity distribution within 3 necessary to provide a definitive scientific base for any the embassy. national exposure standard. Over the years, the Laboratory has been tasked by The lack of a national safety standard for exposure the U.S. Armed Forces with numerous systems engi- to microwave radiation and the continuing reports of neering evaluations, and in 1982, a major biological potential health hazards associated with exposure have research program was begun to investigate potential alarmed the general public, and it is no longer uncom- health hazards from exposure to microwave radiation. mon for a legal challenge to be instituted whenever a This research program, under the direction of APL’s company undertakes the installation of a new facility, Henry A. Kues, is a cooperative effort with The especially for communications systems. In an effort to Wilmer Ophthalmological Institute of The Johns protect the public health, to provide a forum for public Hopkins University School of Medicine, the Tri- education and public input regarding the installation Service Microwave Bioeffects Program (formerly the of a facility, and to allow for monitoring of power Walter Reed Army Institute of Research/Microwave density exposure levels, the city of Stamford, Connect- Branch), and the Food and Drug Administration. icut, instituted a novel approach to address these issues. Using animal models, studies conducted under this JOHNS HOPKINS APL TECHNICAL DIGEST, VOLUME 18, NUMBER 2 (1997) 289 H. A. KUES, P. E. MAZIK, AND J. C. MONAHAN program demonstrated a direct relationship between also included a provision specifying a field survey by a RF exposure and the production of ocular changes, scientific panel with sensitive RF detection meters including increased vascular permeability, altered prior to the public hearing. Presently, the city of Stam- electrophysiological responses indicative of impaired ford is the only municipality to have such an ordinance visual function, and the frank destruction of corneal regulated by a local health department. It should be and retinal tissue.4 noted that public utilities with antennas mounted on Numerous animal studies have documented the towers fall under the exclusive jurisdiction of the state production of other biological consequences from RF of Connecticut’s Department of Public Utility Control. exposure, including compromised immunity, altered neurological function, genetic effects, altered drug activity, and a variety of behavioral effects.5–11 Howev- THE CITY OF STAMFORD RF er, not all experimental studies demonstrated clear PROTECTION ORDINANCE effects, and, in fact, some studies failed to find any After receiving an application for a microwave- effect for a given endpoint, especially at low exposure emitting facility, the Director of Health convenes a levels. The lack of consistent findings has fueled debate panel of three experts in the field of bioelectromagnetic within the scientific community concerning the appli- science. The Stamford Health Department selects an cability of some of the data to humans, especially re- expert, the applicant selects one, and the third expert garding safe or unsafe exposure levels. This lack of is a neutral party chosen by the other two experts. In complete agreement has resulted in some foreign gov- lieu of an application fee, the applicant is responsible ernments and several nongovernmental bodies in the for paying any fees and expenses charged by the three United States adopting somewhat different recommen- experts for their services. A timeline of this application 12–17 dations for safe exposure levels. Currently, the review process is shown in Fig. 2. United States has no national standard to ensure safe The department then schedules an evening public exposure to RF radiation. Thus, industry, the military, hearing. Before the hearing, the panel of experts con- and local municipalities usually adopt one of the non- ducts a field survey of the proposed site and surrounding binding recommendations such as the American Na- neighborhood with Health Department staff. The ap- tional Standards Institute/Institute of Electrical and plicant provides sensitive electronic equipment to Electronics Engineers (ANSI/IEEE) C95.1-1991 or the measure background RF levels in the vicinity of the National Council on Radiation Protection and Mea- site, and, if possible, power density measurements are surements guidelines. A few local jurisdictions have set taken at similar operating sites at other nearby loca- 18–20 their own standards as has the Laboratory. tions to obtain comparative data on existing facilities. In 1982, considerable concern was raised about the The applicant provides public notice of the evening effects of exposure