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Natural and Man-Made Environmental Exposures to Static and ELF Electromagnetic Fields Grandolfo, M., and P. Vecchia Biological Effects and Dosimetry of Static and ELF Electromagnetic Fields, M. Grandolfo, S. M. Michaelson, and A. Rindi, Editors; New York, Plenum Press, pages 49-70, 19 references 1985 A review of natural background noise and man made environmental exposures in the 0 to 300 hertz (Hz) extremely low frequency (ELF) region was presented. According to the authors, natural ELF signals have their origin in lightning strokes, the earth's magnetic field, and the ionosphere. Static, ELF electric, and magnetic fields are of importance in the function of brain, bone growth and regeneration, and embryonic development. Biological sources produce magnetic fields that are substantially weaker than the earth's magnetic field. The strongest field is associated with the magnetized contaminants in the lung. Of several tissues that generate magnetic fields, the heart and eyes produce the strongest signals. The main sources of man made fields, which are stronger than those of natural origin, are high voltage transmission lines and devices with current carrying wires. Persons working at substations and those living close to high voltage lines, as well as workers in the electrochemical industry and research laboratories may be exposed to high electric and magnetic field strengths. High magnetic fields are generated by superconducting magnets, fusion reactors, and particle accelerators. Electric fields generated by home appliances vary from 2 volts/meter (V/m) for an incandescent light bulb to 250V/m for an electric blanket. The magnetic flux densities span ranges from between 0.1 and 1 microtesla produced by a refrigerator to between 1000 and 2500 microtesla generated by a 325 watt soldering gun, magnetic stirrer, power feeder cable, and hair drier. ELF fields are also generated by devices such as nuclear magnetic resonance instruments used in biological and diagnostic studies. Household appliances produce leakage currents that are below the values set by the American National Standard Institute.

Extremely Low Frequency Electromagnetic Emissions From Video Display Terminals And Other Devices Stuchly, M. A., D. W. Lecuyer, and R. D. Mann Health Physics, Vol. 45, No. 3, pages 713-722, 39 references September 1983 CODEN: HLTPAO Magnetic fields from video display terminals (VDT) were assessed. Frequency spectrum and magnetic field intensity from 5 to 500 Hertz (Hz) were measured in front of the screen in three VDT and at the yoke in back of one model and for various electrical devices. The magnetic field intensities at extremely low frequencies (ELF) were determined. The main contribution was at 60Hz. Odd harmonics had higher intensities than even harmonics and intensity decreased for higher harmonics. Total magnetic field intensity at ELF from 60 to 420Hz in the three VDT were 0.097, 0.213, and 0.217 Amperes per meter (A/m) at 30 centimeters (cm); 0.084, 0.97, and 0.131A/m at 50cm; and 0.063, 0.063, and 0.042A/m with the power off. In the VDT measured at the yoke in back, the total intensity over the range was 4.019A/m. Over the frequency range from 60 to 420Hz, the total magnetic field intensity for an electric typewriter at the keyboard was 0.127A/m and at the back was 1.64A/m; for a pocket calculator transformer, the magnetic field density was 0.558A/m; for a base board heater, 3.965A/m; for a hair dryer, 0.236A/m; a hand mixer, 9.295A/m; and for an electric kettle, 0.723A/m. The authors conclude that magnetic fields at ELF can interact with biological systems directly or indirectly. Electromagnetic emissions at ELF from VDT are of such low intensities that they are unlikely to be of any health significance.

File 149:HEALTH PERIODICALS DATABASE 1976-92/WEEK 28 TITLE: EMF-cancer link still murky. (electromagnetic fields) AUTHOR: Pool, Robert JOURNAL: Nature VOL.: v349 ISSUE: n6310 PAGINATION: p554(l) PUBLICATION DATE: Feb 14, 1991 ABSTRACT: In the past several years, it has been suggested that electromagnetic fields (EMFs) generated by power lines and electrical appliances, such as televisions, hair dryers, microwave ovens, or even curling irons, may cause health problems. Some studies show increased rates of brain cancer and leukemia among electrical workers and others who are exposed to strong EMFs at their jobs. It has also been suggested that children exposed to EMFs may have two to three times the risk of developing leukemia. John Peters, an epidemiologist from the University of Southern California, has recently released a study implying that the risks of developing leukemia are correlated with the level of exposure to EMFs. The study examined 2321eukemia patients under than age of 10, and a group of control subjects that were matched for age, sex, and race. The amount of EMF exposure for each child was determined in a number of ways. No correlation was found between the incidence of leukemia and the electric field exposure as measured by spot checking. An insignificant correlation was noted between incidence of leukemia and levels of exposure to magnetic fields, as measured by a continual measurements over a 24-hour period. A significant correlation was seen between the EMF exposure, as measured by wire coding, and an increased risk of leukemia. Those with the highest level of exposure had a 2.5-fold greater risk of developing leukemia. It is not understood how these differences in correlation depend on the way the EMFs are measured. It is possible that some types of EMF exposure may lead to an increased risk of leukemia. On the other hand, measurements taken by wire coding may be more sensitive. Further study is needed to see what factors are being measured by the wire coding and not by the other methods. Until that is understood, it is not clear if exposure to high levels of EMFs is related to an increased risk of leukemia. (Consumer Summary produced by Reliance Medical Information, Inc.) -13-

TITLE: Asbestos removal, health hazards, and the EPA. (Council Report) JOURNAL: JAMA, The Journal of the American Medical Association VOL.: v266 ISSUE: n5 PAGINATION: p696(2) PUBLICATION DATE: August 7, 1991 AVAILABILITY: FULL TEXT Online LINE COUNT: 00224 ABSTRACT: The Environmental Protection Agency (EPA) is often criticized for failing to respond vigorously and rapidly enough to potential hazards. Ironically, the EPA is now being accused by some of being overzealous. As it became clear that exposure to asbestos fibers in the air was a cause of lung disease, including a rare form of cancer, it became disturbing to consider how widespread the use of the fiber was. The strong and fireproof mineral fiber was also economical, and found its way into building materials, packing materials, and ceiling tiles. Even filters for drinking water were made of asbestos and tiny pieces of broken asbestos fiber could be found in the water. The removal of asbestos-containing materials was mandated for the nation's public schools, and 40 states have currently achieved over 90 percent compliance with the new standards. The cost for the renovations has been estimated at $3.8 billion. If public and commercial buildings are required to perform similar renovations, the EPA estimates 730,000 sites will need work costing from $100 to $150 billion. The issue hinges on the evaluation of the hazard itself. No one denies that asbestos is hazardous, but the amount of asbestos fiber in the air in many buildings is no greater than that contained in the outside air. However, it is also clear that some workers such as pipe fitters, maintenance workers, custodians, and firemen are likely to find themselves in situations where the exposure is much greater. Unfortunately, few data are available to accurately estimate the risk of low-level exposure to asbestos. Furthermore, it is unlikely that the mineral can be completely eliminated from the environment. Therefore, any rational program that is within society's economic resources must be based on some estimate of a reasonable limit, rather than the eradication of all exposure. The EPA should also attempt to enlighten society about the actual risks and the projected costs. All health workers should endeavor to educate the public about other hazards that are much more serious than asbestos exposure, including smoking and drug abuse. Even inadequate diet and inadequate exercise are more serious health threats to the average citizen than is asbestos exposure.