News:

Available Data Do Not Show Health Hazard to Cape Cod Residents From
Air Force PAVE PAWS Radar

(original document: http://www4.nationalacademies.org/news.nsf/isbn/0309093090?OpenDocument)

SANDWICH, MASS. -- Based on the available scientific data, there is no evidence of adverse health effects to Cape Cod residents from long-term exposure to radiofrequency energy from a nearby U.S. Air Force radar installation, says a new report from the National Academies' National Research Council. The committee that wrote the report specifically investigated whether the PAVE PAWS radar might be responsible in part for the reported higher rates of certain cancers in the area -- long a concern of area residents. The committee concluded that there is no increase in the total number of cancers or in specific cancers of the prostate, breast, lung, or colon due to radiation exposure from PAVE PAWS. However, the committee found in the scientific literature a few biological responses to radiofrequency exposures that were statistically significant. Such responses do not necessarily result in adverse health effects, the report notes, but additional studies are recommended to better discern the significance, if any, of those findings.

Operated on Cape Cod since 1979 by the U.S. Air Force Space Command, PAVE PAWS is a phased-array warning system designed to detect and track sea-launched and intercontinental ballistic missiles. PAVE PAWS was the subject of two 1979 Research Council reports that examined the safety and possible health effects of the radar. The new report follows up on the findings and recommendations of the 1979 studies.

"To address the public's concerns, we carefully evaluated all the available scientific evidence to determine whether there is a reasonable degree of certainty about the presence or absence of harm from PAVE PAWS," said committee chair Frank S. Barnes, distinguished professor, department of electrical and computer engineering, University of Colorado, Boulder.

The committee found no evidence of a mechanism or pathway by which levels of radiofrequency energy similar to those emitted by PAVE PAWS could change biological processes. Recent data on the PAVE PAWS waveform -- a graphic plot of radiofrequency emissions -- show exposure levels similar to those of "dish" radars to which the public also are continuously exposed.

The committee's analysis of long-term exposure to PAVE PAWS radar showed no increased incidence of cancer over time. In fact, a comparison of the standard cancer incidence rate for total cancers and breast, colon, lung, and prostate cancer in five towns of upper Cape Cod for the periods 1987-1994 and 1995-1999 revealed no consistent pattern of increase. Cancer is one important health measure, but the report also looked at a measure of overall health -- premature mortality before age 75 -- and this analysis showed that in 2001 the towns of Barnstable, Falmouth, Mashpee, and Sandwich each had lower rates than the state average. While the town of Bourne had an elevated premature mortality for that same year, the increase was not statistically significant.

One of the Research Council's 1979 reports stated, "PAVE PAWS radar may be anticipated to expose a limited number of members of the general public intermittently to low intensities of pulse-modulated microwave fields… There are no known irreversible effects of such exposure on either morbidity or mortality in humans or other species." But that report also recommended that the Air Force conduct additional research on possible health effects of PAVE PAWS radiation. The new report finds no evidence that the Air Force followed up substantially on the 1979 recommendation for further research.

The new report again recommends additional biological studies to investigate possible health effects of PAVE PAWS exposure in cell and animal systems. Specifically, it calls for the application of new biological research tools in studies using simulated exposures to PAVE PAWS radiation. The committee also requests studies of plant growth in the vicinity of PAVE PAWS, such as tree-ring growth before and after the radar went into operation. Though not directly applicable to human health, these studies do provide long-term data on biological effects under conditions similar to human exposure. The committee noted the existence of a recently initiated epidemiological study of health effects of PAVE PAWS, but the study was not completed in time to be a part of the current report. The report did note that future epidemiological studies would not be of value and should not be undertaken unless they have sufficient statistical power to actually detect health effects in the Cape Cod population.

In response to concerns voiced by some members of the public that classified data or reports that demonstrated effects of phased-array radar at low power densities might exist, the committee specifically looked to determine whether such studies or other useful information does exist. Committee members with scientific expertise and proper security clearances were tasked with examining classified research done by the U.S. Air Force that might show evidence of biological effects of radiation similar to PAVE PAWS that is relevant to humans. The committee found none.

The study was sponsored by the U.S. Air Force. The National Research Council is the principal operating arm of the National Academy of Sciences and the National Academy of Engineering. It is a private, nonprofit institution that provides science and technology advice under a congressional charter. A committee roster follows.

Copies of An Assessment of Potential Health Effects From Exposure to PAVE PAWS Low-Level Phased-Array Radiofrequency Energy will be available later this winter from the National Academies Press; tel. 202-334-3313 or 1-800-624-6242 or on the Internet at http://www.nap.edu. Reporters may obtain a pre-publication copy from the Office of News and Public Information (contacts listed above).