Epidemiological studies of radio-frequency radiation: current status and areas of concern

These comments deal with the possible impact on human populations of intense sources of radio-frequency radiation, and not the much lower level of the usual sources of such radiation associated, for example with household appliances. These intense sources were developed and extensively used first in World War II (1940–1945). Much of the health evaluation has been done by, and for, military organizations. There are important differences in the energy generated by low frequency (ELF) and radar; it then follows that there may be differences in their effects on human populations. Problems common to both types are: (1) the uncertainty as to biological mechanisms; (2) weak experimental evidence of effect; (3) epidemiological preoccupation with carcinogenesis, with its latency and low incidence. For both types there is the presumption of greater occupational than community risk, the latter often not well studied, and problems as to exposure quantification and specificity. To these one must add (4) the inherently epidemiological problems of a study at a given source of adequate sample size, case-findings, exposure estimation, confounders, and residential and job instability. Despite these problems, there are findings from sets of studies which suggest four possible health effects from radar (radio-frequency radiation) exposure: (A) disturbances in blood counts, not necessarily of clinical severity; (B) changes in chromosomes of white blood cells; (C) increases in frequency of unfavorable reproductive outcomes, especially spontaneous abortion, and (D) increases in cancers of certain sites. A review article on this topic was published (although after the Skrunda meeting) [6] providing evidence from various exposures on such possible effects. A brief critique is provided of evidence on these four possible effects, identifying some areas of uncertainty for which studies at sites like Skrunda could provide useful information.