An Assessment of Potential Health Effects from Exposure to PAVE PAWS Low-Level Phased-Array Radiofrequency Energy (2005)

Because radars are an important feature in the operation of the military in times of peace and war and because microwave and laser systems have been developed as strategic weapons to deliver energy as well as systems for guidance or surveillance, one would expect that the U.S. Air Force and perhaps other branches of the military might have conducted research to explore effects of microwaves on biological systems. A major source of that type of research has been a responsibility of the Directed Energy Bioeffects Division in the Human Effects Division (HED) of the Air Force Research Laboratories (AFRL) at Brooks Air Force Base in San Antonio, Texas. For obvious reasons, some of that work has been classified by the U.S. government, while other results in biological systems have been published in the open scientific literature or in unclassified U.S. Department of Defense documents. The congressionally mandated study conducted by the NRC committee included a charge to examine and assess all classified national security data that might be relevant to PAVE PAWS.

In order to ascertain whether research by the U.S. Air Force had produced any evidence for biological effects that might relate to potential health effects of electromagnetic radiation with characteristics relevant to the radiations produced by the PAVE PAWS beam, members of the NRC committee with appropriate personnel security clearances and expertise in the engineering and biological disciplines were asked to review the Air Force’s classified research and results. To

do that part of the charge, two site visits were conducted. The first was a preliminary visit conducted on April 25, 2002, in which the goal was to examine the reports and documents summarizing all of the classified research results that might be relevant to the PAVE PAWS study and to determine whether additional expertise and a second visit would be necessary to review the Air Force’s results of classified research. The Director of the Board on Radiation Effects Research and two committee members, one with biological expertise and one with physics expertise, examined the classified reports and data summaries in the Directed Energy Bioeffects Division of the laboratories at Brooks AFB. The site-visit team asked the Air Force to provide all reports and data summaries for all electromagnetic radiation research related to the PAVE PAWS beam characteristics. This visit included an extensive presentation by Dr. Albanese, in addition to presentations by other scientists, including Air Force personnel and civilians who were associated and familiar with the Air Force’s research activities related to electromagnetic radiation interactions with biological systems. The team was hosted in Building 1162 (Tejeda Laboratory) at Brooks Air Force Base by Richard L. Miller, Ph.D., Chief, Directed Energy Bioeffects Division (AFRL/HED). Also present were Major Lester Ogawa, Dr. Johnathan Kiel, the Senior Scientist in Electromagnetic Radiation Effects, and Dr. Walter Rogers. At the time of the NRC committee’s visit, Dr. Rogers was a Research Electrophysiologist for Veridian, but he had been the key investigator on the Electromagnetic Health and Safety program report when he was an employee for Southwest Research Institute. Part of the review included a discussion and answer session with scientists and Air Force administrative staff and part of the review included an executive session in which the NRC site-visit team examined reports and data summaries.

The second site visit was conducted on January 30-31, 2003. For the second visit, two additional committee members with appropriate personnel security clearance and scientific expertise (the additional expertise requirement was based on the review conducted by the first review team) were added to the team. In addition, a physician with appropriate personnel security clearance was included as an unpaid consultant. A total of four committee members, plus an M.D. consultant (a member of the Institute of Medicine of the National Academies) and the NRC board director, reviewed the classified information provided during the two-day visit.

Prior to the site-visit team’s arrival, the full committee’s members developed a series of questions that they instructed the review team to ask of the Air Force during their visit. Those questions included:

1. Where did the parameter “1 volt/meter/nanosecond rise time” come from?

2. Does the Air Force have any evidence for actual measurements of precursors?

3. Does the Department of Defense have any other data (molecular, cellular, or animal) that are relevant to the PAVE PAWS exposures (i.e., other experimen-

tal results known to the Air Force from experiments conducted using relevant wavelengths and power densities that are below thermal thresholds)?

In addition to focusing on a discussion of the Air Force’s answers to the above questions, a major focus of the review was a final report of the U.S. Air Force’s Electromagnetic Health and Safety (EHS) research program. The results of the Air Force-sponsored studies conducted over a period of approximately 15 years (from the 1980s to 1996) were reviewed from the perspective of whether any of the results obtained are relevant to exposure of humans to the PAVE PAWS system or informative about effects that might relate to potential human health effects from exposures to PAVE PAWS. As stated in the final report provided by the Air Force, the thrust of the EHS program is summed up by the unclassified title Biological Effects of Exposure to Ultra-wideband Electromagnetic Energy (U) (AFRL-HEX 2002). Copies of the final classified report were provided to each review-team member for use during the two-day visit.

In its review of the classified data, the review team had to rely on the responsible Air Force personnel to provide access to all data as requested by the committee. The Air Force administrative personnel were very cooperative in making the classified materials of the EHS program available to the committee. In this particular review, the committee has no evidence to suggest that summaries of data obtained by the Air Force in research related to the EHS research program were withheld from the committee. Because of the large volume of data obtained over several years in this multimillion-dollar research program, the reviewed materials were primarily summary and tabulated material. Information provided in the summary reports did not indicate the existence of biological effects in the accumulated data that are relative to PAVE PAWS exposures. It was helpful that the review team was able to meet separately with Dr. Albanese, given that he had raised his personal concerns on several occasions to the full NRC committee and to the site-visit team. Dr. Albanese was able to observe the materials and briefings that were provided to the review team, and was asked specifically whether there was any additional information that should be reviewed by the team. The two suggestions made by Dr. Albanese were followed up by the team: first, the suggestion that the U.S. Navy might have conducted some relevant research; and second, the suggestion that contractors at other sites conducted experiments that might be relevant (see Chapter 5, Annex 5-2). Finally, members of the review team and the full NRC committee feel that it would be prudent for the Air Force to declassify as much of the classified EHS material as possible in the interest of improving the public’s confidence in the U.S. Air Force’s disclosure, even though the review team saw no evidence of results that would change the NRC committee’s conclusions or recommendations related to its assessment.

The NRC’s review team members produced an unclassified summary and presented it to the full committee at its meeting the following month in Washington, DC, February 10-11, 2003. Based on the report by the review-team members,

and following discussion by the full committee, the following conclusions and findings were made:

1. As best as could be determined from materials provided at our request, the Air Force did not design or conduct any classified studies addressing long-term exposure effects experiments directly relevant to the PAVE PAWS exposure conditions and therefore did not respond to the recommendations in the 1979 NRC Report.¹

2. However, the Air Force has completed a series of studies using high-power, short-duration RF exposures that include energy in the frequency range and average power of PAVE PAWS.

3. There are no classified experimental studies in the EHS program relating to carcinogenesis.

Experimental results reviewed by the site-visit team, while not generally statistically significant or at exposure conditions representative of PAVE PAWS, suggest that stimulation of cardiac or skeletal muscle might be demonstrated at high power levels and sub-second exposures. It was somewhat disappointing to the review team that some of the data summaries could not be easily traced back to certain key experimental characteristics.

The 1 volt/meter/nanosecond slope appears to be based on Dr. Albanese’s theoretical modeling and measurements in “biologically relevant” models that have been declassified.

The visit did not reveal any additional measurements of, or demonstration of, precursors in biological or model systems.

The review team learned that the U.S. Navy has conducted studies of transient microwave propagation in ocean media. The Navy was contacted and the committee received an unclassified report from Naval Surface Weapons Center (NSWC) (see Chapter 5 this report).

NRC (National Research Council). 1979. Analysis of the Exposure Levels and Potential Biologic Effects of the PAVE PAWS Radar System. Washington, DC: National Academy Press.

AFRL-HEX (Air Force Research Laboratory–Health Effects Classification). 2002. Biological Effects of Exposure to Ultra-wideband Electromagnetic Energy (U). AFRL-HEX classified report. Brooks Air Force Base, San Antonio, TX.