- Radio waves and microwaves consist of electrical and Magnetic fields transmitted through space in the form of invisible, penetrating waves of energy known as non-ionizing radiation (which we shall abbreviate to NIR). NIR is different from the “ionizing” radiation produced by x-ray machines and nuclear power plants or nuclear weapons.
- NIR is produced naturally by the sun but radio waves and microwaves created in the home, in industry and in government (primarily military) activities can increase our exposure to levels a million times higher than natural levels.
- The energy carried by the waves hitting a specific area is referred to as the power density and is normally measured in terms of milliwatts per square centimeter. mW/cm2.
- Low levels (below 10 mW/cm2) of NIR have been found to produce many adverse health effects in animals including temporary sterility, genetic changes and changes in the transmission of nerve impulses. The U.S. Environmental Protection Agency has found preliminary evidence that these low levels may affect the immune system, which means the body may be less able to fight off disease.
- At high levels (above 100 mW/cm2) NIR has been found to cause such adverse health effects in humans as cancer, nervous disorders, cataracts, heart disease, permanent sterility, genetic damage and, if exposure is prolonged, death.
- The World Health Organization found a highly significant position correlation between an unusual increase in heart disease and cancer and the installation of a large radar station (which emits high levels of NIR at ground level) in an isolated part of Finland called North Karelia.
- Unusual cataracts have been found in the eyes of radar workers who are exposed to high levels of NIR. Unlike cataracts caused by overexposure to high temperatures which form on the front surface of the eye lens, these cataracts form on the back surface of the lens, which is where radiation-caused cataracts could be expected to occur.
- Radio waves and microwaves are used for communication, in industry, for medical purposes and in the home. Radio and TV, long-distance telephone transmissions, citizen band radios (CBs), radar, taxi dispatch lines and communication satellites all use NIR to send their signals. High voltage power lines also emit NIR. In industry and medicine, radio frequency equipment is used for drying, heating and cutting. In the home, burglar alarms, microwave ovens, garage door openers and electronic toys emit low levels of NIR.
- The recommended allowable level of NIR on the job in the United States (10 mW/cm2) is 1,000 times higher than the standard set in the Soviet Union (0.01 mW/cm2). In addition, the Soviet Union has set a standard for exposure to NIR for the general public at 0.005 mW/cm2. The United States has no such standard for the general public.
- The use of microwaves and radio waves is rapidly increasing in the United States. Today there are 35 million electromagnetic devices for drying and heating processes in industry, more than 10 million microwave ovens in use, over 30 million citizen band radios and over 20 million radar sources. Microwave and radio wave use in the United States increases an estimated 15 percent per year.
Ionizing radiation, such as gamma rays (from radioactive materials used iii nuclear power plants or nuclear weapons) and x-rays, has the ability to destroy or cause mutation in body cells. In contrast, NIR does not generally have enough energy to cause this serious damage. This is because it is of longer wavelength and lower frequency (a smaller number of waves pass a certain point in a specified time). The longer wave lengths of NIR allow radio wave and microwave energy to travel long distances and penetrate body tissue.
When the source of microwaves or radio waves is turned off, emission of NIR is also stopped. This is different from many sources of ionizing radiation, like uranium, which emit constantly for many years.
The energy that microwaves and radio waves carry is absorbed by body molecules and creates heat in the body. This is why microwaves cook food. The heat created by the microwaves or radio waves in turn causes body molecules to be set into rapid motion, creating heat stress on all or parts of the body. Besides heat stress, many body organs have small blood vessels which make it difficult to carry heat away quickly, which could result in damage to that organ. Organs that are particularly sensitive to heat are the eyes, gall bladder, digestive tract, urinary bladder and the testes.
The U.S. Occupational Safety and Health ‘Administration recommends that exposure to NIR for workers be limited to 10 mW/cm2. This standard is not mandatory and many workers are exposed to levels much higher than this. One study found 90 percent of radio-frequency equipment operators and nearby workers are exposed to levels equal to or higher than 10 mW/cm2. The highest exposure level found was 1000 mW/cm2. About 25 percent of all workers in the United States are exposed to NIR.
The U.S. Food and Drug Administration has the authority to regulate the levels of radiation emitted from consumer products. Microwave ovens made after 1976 are subject to emission standards of mW/cm2 or lower measured 5 centimeters (about 2 inches) from the oven’s surface at the time of purchase. Most ovens emit radiation at levels between 0.1 and 1 mW/cm2, a range well within the standard. However, in older ovens gaps sometimes develop between the door and the frame which can allow higher emission of radiation. If the door frames are not kept clean and unobstructed during use, radiation can leak out. There is no way to detect these leaks without the proper monitoring device.
The U.S. Environmental Protection Agency regulates levels of radiation in the environment. No federal standards protect the general public from exposure to NIR. All of us are exposed to NIR from communication systems. Radiation from these sources is highest near radio and television transmitters. Levels as high as 21 mW/cm2 were found in the upper floors of office buildings close to the transmitters. On the whole, however, most city dwellers are exposed to levels lower than 0.0003 mW/cm2.
High levels of NIR are known to produce serious adverse health effects in humans. Additionally, levels of NIR below 10 mW/cm2 is a recommended level and not required by law. This level also ignores the increasing evidence of adverse effects at lower levels. Workers using radio frequency equipment should ask that their union or employer verify that at least the standard of 10 mW/cm2 is being met.
Consumers can minimize their exposure to non ionizing radiation by limiting their use of products emitting this radiation.
Unfortunately, however, the general public can do little to avoid exposure to NIR from communication sources. Public pressure can be put on the U.S. Department of Health and Human Services to establish and enforce a standard for exposure to the general.