Evidence shows almost a direct link between electromagnetic fields and cancer in rats. Researchers at Battell Pacific Northwest Laboratory in Richland, Washington, have shown that electromagnetic fields suppress the levels of a certain hormone called melatonin. Melatonin is produced by the pineal gland in the central part of the brain. It is a regulatory hormone and also modifies the functioning of the immune system. Low levels of melatonin have been linked to breast cancer as well as prostate cancer. Animal studies show that electromagnetic fields produce low melatonin, which, in turn, then increases the incidence of breast cancer and prostate cancer. These animal studies have been repeated and corroborated in multiple centers throughout North America. (42)
High- And Low-Voltage Wires
Many studies of the effects of electromagnetic fields on humans have also been done. Children and adults in Colorado living close to high-tension wires had a definite increase of all cancers. The likelihood of getting cancer is twice as high for children near the power lines. (43,44) A number of other investigations have corroborated these findings and have shown that men exposed to electrical and magnetic fields at work have an increased risk of leukemia, especially acute myeloid leukemia, brain tumors, and breast cancer. (49) Researchers at the University of California in Riverside confirm these results and say exposure to common sources of low- and high-energy electromagnetic radiation from overhead power lines probably promotes the growth of malignant tumors. (50) Many of these studies involve high-tension wires with 60 Hz (60 electromagnetic cycles per second).
It had been thought that the low-voltage power lines which had low frequencies and thus low energies would be too weak to have any biological effects. However, epidemiological studies show that low frequency electromagnetic fields produce weak electric fields in our bodies, affecting such biological function as hormone levels, the binding levels of ions to cell membranes, and certain genetic processes inside the cell such as RNA and protein synthesis. Calcium ions in the cell play a major role in cell division, which, in turn, has an important role in cancer promotion.
A study done by Savitz at the University of North Carolina in Chapel Hill measured the proximity of homes to power lines and also the low voltage of electrical and magnetic fields within homes. There was a positive correlation between childhood cancers, including leukemias and brain tumors, and the magnetic fields generated by the power lines. This study is important because it investigated high-voltage lines as well as low-voltage lines, which are on "telephone" poles in our cities. All the childhood cancer studies are significant because they are consistent and have been corroborated. They show an increased incidence of malignancies among people with long-term exposure to electromagnetic fields.
Computer Video Display Monitors
A concern that has commanded major news media coverage in the last several years is computer video display monitors and their potential to cause health problems. The "extremely-low-frequency" magnetic fields produced by these video monitors have been linked to cancers, breast disorders, and other health problems. The United States Environmental Protection Agency recommended that the extremely-low-frequency radiation fields produced by such display monitors be categorized as probable human carcinogens. The EPA states that "the findings show a consistent pattern of response that suggests, but does not prove, a causal link" between radiation levels and cancer in people. (50) In March 1990, Dr. William Farland, director of the EPA's Office of Health and Environmental Assessment, ordered that the researchers' recommendation be deleted.
A study by the magazine MACWORLD of monitors manufactured by different companies found certain uses to be hazardous and suggested several precautions. Workers should sit at least two feet away from the front of the monitor and stay at least four feet away from the back or sides of a coworker's monitor. The same precautions should be applied to laser printers. Color monitors produce more electromagnetic radiation than do monochrome monitors. The amount of radiation, it was discovered, is always higher at the sides, back and top of the monitor. The more powerful the monitor, the more radiation is emitted.
Some American computer makers already have low-radiation monitors for sale in Europe, where standards set by the government as well as their unions are very strict. IBM sells low-radiation monitors here in America but does not advertise them, perhaps fearing that these would create concern and anxiety about other terminals that the company produces. A review of sixteen studies shows that the preponderance of evidence links video display monitors with a risk of spontaneous abortion. (52)
Magnetic Resonance Imaging Scans
In the last ten years or so, there has been widespread use of magnetic resonance imaging scans (MRI scans). In many instances, MRI scans show more detail and hence give more information on a patient than conventional CT scans. Up until now, MRI scans have been thought to be without risk to the patient, that is, no radiation exposure or other harm. However, the newest and fastest MRI scanners may not be entirely safe.
Patients undergoing MRI scanning are exposed to three types of electromagnetic radiation: static magnetic fields, pulsed radiofrequency (RF) electromagnetic fields, and gradient (time-varying) fields. Atoms of all tissues resonate at specific frequencies within an electromagnetic field and produce radiofrequency signals, which are converted into images by MRI scanners.
The newest and fastest MRI scanners rely on the time-varying fields to obtain large amounts of information in milliseconds compared to the ten minutes or more needed by the conventional MRI scanners. The tremendous speed with which the newest MRI scanners acquire information results in a clearer image-one that is not distorted by patient movement or heartbeat-and a reduction in time for the patient to be in the magnet, which may also reduce the incidence of claustrophobia. However, time-varying fields, unlike static fields used in conventional scanners, produce electric currents in the body. These currents can cause cardiac arrhythmias or peripheral nerve stimulation, the latter of which has already been reported in three patients. There is, then, a potential for problems in patients with existing heart disease or seizure disorders. Only further research will help delineate the potential for harm to the body with the use of these very fast MRI scanners.
Electromagnetic fields have been used therapeutically for years to increase cell activity and heal bone fractures. Researchers report that cancer cells reproduce faster after exposure to electromagnetic fields and that these electromagnetic waves increase the activity of a certain enzyme called ornithine decarboxylase, which is involved in DNA synthesis and cell growth. (53) Certain cancer-promoting chemicals also stimulate the activity of this enzyme, and prior exposure to electromagnetic fields potentiate this effect. Exposure to the electromagnetic fields may alter the cancer cell membranes and make them more resistant to the immune system. (54)
Electromagnetic fields have other health consequences. Microwaves affect our circadian rhythms, which in turn affect our sleep patterns, growth, and repair mechanisms. The waves also affect the results of IQ tests in animals. Still other studies show that electromagnetic fields alter cortisol output, which, when secreted in larger amounts, suppresses the immune system.
With the fixed amount of land in our country and the fact that the population is growing, the demand for electricity will increase by about 40 percent by the year 2000. The proximity between people and high-tension wires will have to lessen to accommodate the increased demand. Utility companies may also choose to increase the voltage of the power lines to meet this growing need. Larger power lines will generate stronger electromagnetic fields and
Addressing the Problem
There are some simple steps that have been taken to minimize exposure to electromagnetic fields. There is already a way to reduce electromagnetic radiation from video display terminals. There are electric blankets made with reduced electromagnetic field strengths. Or simply use electric blankets only to preheat the bed. Redesign home appliances to minimize or eliminate fields. Move electric alarm clocks as far away from your bed as is practical. Route new transmission lines to avoid developed areas and increase the distance from the lines to the houses. Some utility companies are arranging their high voltage transmission lines to reduce the magnetic fields. The problem is that little can be done to reduce the electromagnetic fields from the low-voltage lines within our cities.
Electromagnetic waves do, in fact, have health consequences and are probably associated with the development of cancer. We obviously need to be wary about where we live, avoid high-tension wires, and take other common sense precautions.
From Cancer and Nutrition by Charles Simone, © 1992. Published by Avery Publishing, New York. For personal use only; neither the digital nor printed copy may be copied or sold. Reproduced by permission.