Nexus - 0212 - New Times Magazine-pages

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As humans also absorb microwave radiation and heat up accord- ingly, the possibility of hazard from microwave exposure prompted researchers in the early 1950s to consider setting exposure guide- lines. In 1953, H.P. Schwan of the University of Pennsylvania pro- posed that human exposure be limited to a maximum average power density of 100 watts per square metre or 10 milliwatts per square centimetre. Schwan's proposal, directed to the US Navy, was based on a calculation that exposure to this incident power should raise the temperature of the body by no more than 1°C, while power densities 10 times greater might produce heat damage. Thus, the proposed limit allowed a safety margin of about 10 times. The American National Standards Institute (ANSI) adopted this maximum exposure limit in 1966, with many Western nations adopting similar standards thereafter.’ Unfortunately, this maximum average exposure limit, which is still current in most Western countries, did not allow for the possi- bility of microwaves having athermal health effects. Subtle effects of low levels of microwave radiation which were not directly attributable to heating have been reported by researchers, mainly in Europe, since the 1950s but have been largely dismissed by promi- nent American researchers. However, as R. Bowers and J. Frey point out, “scepticism is not a sufficient basis for setting stan- dards".* It is revealing that athermal effects apparently were considered when the USSR established its maximum exposure standard of 10 microwatts per square centimetre per working day, a level 1000 times smaller than the US value. A strong supporter of the high American exposure limit has been Professor S.M. Michaelson of the University of Rochester School of Medicine. In 1967 Michaelson had written: “The occasional Teports of headache, lassitude, stomach-ache pains, sleeplessness, irritability, and other highly subjective symptoms among workers in the vicinity of microwave generating equipment have not been thoroughly investigated. These findings should not be ignored, as similar vague, mild, and undefined symptoms have been experi- enced in the course of microwave studies in this laboratory. Such symptoms could indicate a basic microwave effect." However, six years later at the 1973 Senate hearings he testified that there was no substantial evidence of injury to human beings from microwave radiation below the 10 milliwatt level. Over a decade later, despite a growing literature of subtle and harmful tadio frequency radiation effects, a report by Michaelson still min- imises the significance of much of this research and in his conclud- ing remarks he states, "Depending upon the circumstances, what may be an adverse effect for one individual may be beneficial to another."* Professor Michaelson's research in this instance and in earlier times was supported by the US Air Force. This association of microwave research with the military was mooted by P. Brodeur in 1977’ as the main reason for the US main- taining its high exposure limit. R.O. Becker and G. Selden have pointed out: ur fe cee oti wll "There were persuasive economic reasons why the 10,000 microwatt (=10 mW/cm*) standard was and still is defended at all costs. Lowering it would have curtailed the expansion of military EMR use and cut into the profits of the corporations that supplied the hardware. A reduced standard now would constitute an admission that the old one was unsafe, leading to liability for damage claims from ex-Gls and industrial workers." WHAT ARE THE HARMFUL EFFECTS OF MICROWAVES? It would appear that it is obvious that if the human body is exposed to a high level of microwave radiation it would ‘cook’ much the same way as food ‘cooks’ in a microwave oven. However, microwave ovens use a specific frequency of radiation which is designed both to penetrate and heat. In communication systems a wide range of frequencies is used and the absorption of this radiation varies considerably with frequency. The human body begins to significantly absorb electromagnetic radiation when the frequency exceeds about 15 megahertz. This absorption varies for different parts of the body with certain organs such as the eye and testes being particularly sensitive to microwave heating effects. In the frequency range 70 to 100 megahertz, which overlaps the TV and FM radio broadcast frequencies, the human body acts as an efficient radiation antenna, strongly absorbing these wavelengths.” This radio frequency radiation constitutes a major component of the electronic smog in our environment. Although studies of the health effects of microwaves began in the 1940s,” it was not until the mid-1960s that sufficient data had accumulated to alert observant researchers. In 1964, M.M. Zaret reported that radio frequency radiation may produce capsular cataracts." A few years later testicular damage was reported after repeated exposure to microwaves,” In both these cases high microwave intensities, such as those associated with military radar and which exceeded the 10 milliwatt limit, were involved. What was more alarming was the steady trickle of reports that low levels of microwave exposure could produce a range of ner- vous and vascular symptoms. These were highlighted by Dr M.N. Sadchikova at a symposium in Warsaw in 1973 and later pub- lished.* Sadchikova presented data of a study of 1180 workers who had been exposed to microwave radiation up to about 3 milli- watts per square centimetre compared with a control of 200 people who had not been exposed to microwaves, Sadchikova's results showed that among microwave exposed workers there was a signif- icant increase in neurological complaints, such as heaviness in the head, fatigue, irritability, anxiety, insomnia, and partial loss of memory. Microwave workers also showed a significant increase in cardiovascular symptoms, such as a tendency to slow heartbeat, reduced blood pressure and reduced ventricular capacity. These symptoms which seem to characterise what has been called ‘microwave radiation sickness’ were produced by microwave levels well below the 100 milliwatt safe level of Western countries." The low safety margin of this standard is illustrated by reported cases where servicemen have accidentally been exposed to radar radiation a mere six to nine times the safety standard for a short time period and have been seriously affected. In one case, a fifty-four-year-old man in good health was exposed to the radar for a mere 80 seconds. He experienced severe chest pain, vertigo and a heating sensation of the chest and head. Facial erythema (reddening of the skin) persisted for three days, stomach cramps, gritty eyes and other symptoms persisted for weeks, while insomnia and irritability remained for months. The severity of the complaints peaked three months after the exposure and coincided with the diagnosis of arterial hypertension. A detailed medical examination five months later could reveal no secondary cause of the hypertension. In a second case, a twenty-one-year-old healthy man sustained intermittent exposure for a mere 75 seconds at a similar intensity. He reported very similar initial symptoms.. Four months after his exposure hypertension was again detected. A decade earlier MM. Zaret had suggested a possible connection between radar exposure and hypertension.”* NEXUS¢17 SAFETY LEVELS - BASED ON A GUESS? FEBRUARY-MARCH '93 ©