(word processor parameters LM=8, RM=75, TM=2, BM=2) Taken from KeelyNet BBS (214) 324-3501 Sponsored by Vangard Sciences PO BOX 1031 Mesquite, TX 75150 There are ABSOLUTELY NO RESTRICTIONS on duplicating, publishing or distributing the files on KeelyNet except where noted! May 16, 1993 ELF-RES.ASC -------------------------------------------------------------------- This file shared with KeelyNet courtesy of Walter Mohn. -------------------------------------------------------------------- This article is from the April, 1993 issue of Research & Development Magazine, Des Plaines, IL, page 73. -------------------------------------------------------------------- R&D ENVIRONMENTAL RESEARCH SECTION: "Worry Over Power Lines Likely to Last," by James Glanz Potential hazards of extremely low frequency fields (ELF) have taken an extremely low profile amid public accusations that microwaves from cellular phones might cause brain cancer. Far from the media crowd surrounding the cellular controversy , however, several researchers have expressed the opinion that studies of ELF's potential hazards are more likely to affect American industry and society in the long run. ELF, defined as electromagnetic radiation at frequencies below 300 Hz, includes the 60-cycle radiation emitted by everything from high-tension lines to toasters to video display terminals. "I think most of the heat is still on the power-line issue," says Bill Guy, professor emeritus at the Univ. of Washington's bioengineering center, Seattle. Guy, who has performed numerous laboratory studies on the physiological effects of microwaves, says there is "no documented literature that I know of that would indicate any danger of cancer [caused by] cellular telephones." The scientific record on ELF is less reassuring, says Larry Anderson, a researcher at Pacific Northwest Laboratories (PNL), Richland, WA. "I think what we're seeing is that most recent epidemiological studies tend to support the findings of earlier studies," he says, referring to elevated rates of leukemia for people who live near power lines. Other studies point to slightly increased rates of leukemia and brain cancer for people occupationally exposed to ELF, such as electricians and telecommunications workers. The number of people habitually exposed to ELF is likely to be far higher than those exposed to microwaves from hand-held cellular Page 1 phones, even if the phones do turn out to be a threat. Anyone whose sights are set on proving a link between microwaves and cancer would do well to study the history of such attempts in the ELF regime. Although many researchers are convinced of the link between ELF and cancer, others (such as Robert Adair, a physicist at Yale Univ.) point to the many conflicting studies or ridicule the often marginal statistical certainty of the results. In one case, an epidemiological study found an elevated incidence of cancer among people who lived near power lines, but a later study found that "residential traffic density is strongly associated with childhood cancer...among the same study population," report ed PNL's Thomas Tenforde in last year's Annual Review of Public Health. When they are not taken into account, such "confounding variables" can invalidate statistical conclusions. Particularly damaging to the persuasiveness of the cancer-ELF link is the lack of any established mechanism by which the weak fields that penetrate the body might have a deleterious effect on cells. Adair has written down thermodynamic equations that he says describe the current flowing through cell membranes, and he estimates that random, fluctuating fields around the membranes would have effects thousands of times larger than any external ELFs could have. As a result of such considerations, many researchers are looking for a mechanism by which this naturally occurring noise would " average out," permitting the weak but steady 60-cycle oscillations to have a noticeable effect on cells. In one theory, the ELF fields resonate with natural oscillation frequencies of cellular ions such as calcium and potassium. These frequencies can be related to the cyclotron frequencies of the ions in Earth's magnetic field, or they can be determined by the physiology of cell membranes. Other theories emphasize the spatial coherence of ELF-induced currents over an entire cell. The random currents are again presumed to cancel. Still another approach to the ELF question is to directly examine the effect of the fields on animals and cells in vitro. With these methods, some groups have found deleterious effects - and others have failed to. Despite all this uncertainty, there is one thing the ELF researchers can tell their cellular-phone counterparts for sure: Watch out for politics. "It's driven by factors other than just the science," warns PNL's Anderson of such research. "The issue is one of public interest. For that reason, whether or not there are health effects, we need to get some resolution to it." More Information: Thomas Tenforde (509) 375-3738 FAX (509) 375-3686 Page 2 FIGURE 1 Humans and Power Lines A Current Affair _________ \ / \ / ___/_\_/_\___ | 180 kV/m * |/ \| * | * |\ /| * | |/ \| *** 60 nA/cm^2 ____|_|_|____ /@ @\ * |/|\| * { V } 550 nA/cm^2 * |\-/| * \ - / |\/^\/| 200 nA/cm^2/ \_ |/\-/\| / x-----190 nA/cm^2 |^\/^\/^| //^| |^\\ ||/\|/\|| // | | \\ ||\/|^|\/|| ""' | | `"" ||/\|||/\|| [ ] 250 nA/cm^2 ||\/|^|\/|| ||^|| ||/\|||/\|| || || 370 nA/cm^2 ||\/|^|\/|| || || || ||2000 nA/cm^2 <_| |_> Lightning-rod effect of human magnifies effect of a 60-Hz, 10-kV/m electric field 18-fold. Such fields are commonly produced by over head power lines. The field induces currents of up to 2000 nA/cm^2 in the person's skin. Researchers are trying to find out whether those currents can have adverse effects. Source: William Kaune -------------------------------------------------------------------- If you have comments or other information relating to such topics as this paper covers, please upload to KeelyNet or send to the Vangard Sciences address as listed on the first page. Thank you for your consideration, interest and support. Jerry W. Decker.........Ron Barker...........Chuck Henderson Vangard Sciences/KeelyNet -------------------------------------------------------------------- If we can be of service, you may contact Jerry at (214) 324-8741 or Ron at (214) 242-9346 -------------------------------------------------------------------- Page 3