The Spectrum Between Microwave Radiation and ELF

The following section is on the spectrum of electromagnetic radiation between microwave and ELF. It is part of Chapter 8, Man Made Electromagnetic Radiation Fields, of the book "Cross Currents: the Perils of Electrical Pollution" by Robert O. Becker.

The Spectrum Between Microwave and ELF

All of the above reports deal with electromagnetic fields at opposite ends of the no ionizing portion of the electromagnetic spectrum. The power-frequency fields oscillate at less than 100 times per second, while microwaves oscillate at hundreds of million times per second or more.  Nevertheless, it is apparent that the types of biological effects associated with each are virtually identical.  It is believed that this is the result of the modulation of the high-frequency microwave signal at lower frequencies.

For example, Dr. W. Ross Adey of California’s Loma Linda Medical Center has reported that the release of calcium ions from nerve cells following exposure to 16 Hz may also be produced by exposure of nerve cells to a microwave field odulated at 16 Hz.  The microwave alone (unmodulated) has no such efect.  The two types of modulation that are biologically important are pulsed and amplitude.

Modulation is the secret of transmitting information by means of electromagnetic fields.  AM radio, for example, is amplitude modulated:  the rado receiver “demodulates” the signal, removing the “carrier” radio-frequency wave and saving the slowly rising and falling modulation, which is what we then hear as music or voice.  Transmission of the carrier wave alone would produce no sound, or a steady tone, depending upon the type of AM radio used.  It appears that the body also demodulates the signal when exposed to modulated radio-frequency or microwave fields: the biological effect is that of the low-frequency modulation.

In this view, all biological effects are produced by ELF frequencies.  This makes good sense, because the body systems that pick up the electromagnetic field are “tuned” to the natural frequencies between zero and 30 Hz.  These systems will sense abnormal fields that are close to the normal (between 35 and 500 Hz).  The systems then produce an abnormal effect.  Microwave radar pulsed at 60 Hz would have the same bioeffect as a 60-Hz field alone, which explains the identical effects seen at ELF and microwave frequencies.  It also indicates that all intervening frequencies (VLF, AM radio, FM radio,and TV) will have the same biological effects, since they, too, are modulated.

This intervening portion of the spectrum has received only spotty attention, and the number of reports dealing with specific frequency bands in the radio frequencies is small.  Most attention has been directed to the most common sources of exposure, such as commercial AM and FM radio. In the early 1970s, Dr. William Morton of the Oregon Health Sciences University was asked by the EPA to look into an excessive incidence of uterine Aden carcinoma among residents of a Portland neighborhood that contained an unusual concentration of broadcast towers.  The project was expanded to study the relationship between EPA measurements of FM radio fields in Portland and the incidence of several types of cancer in the same area.  While no relationship with Aden carcinoma was found, a small but significant relationship was found between field intensity in the FM band and the incidence of no lymphatic leukemia.  The EPA took no action on this report.

In 1986, doctors B. S. Anderson and A. Henderson of the Hawaii Department of Health surveyed the city of Honolulu according to census-tract areas. They found that in eight out of nine census tracts containing broadcast towers, the incidence of cancers of all types were significantly higher than in adjacent census tracts that did not have broadcast towers.  No action has been taken by the State of Hawaii Department of Health.